CA2057780A1 - Ink ribbon for thermal transfer printer - Google Patents
Ink ribbon for thermal transfer printerInfo
- Publication number
- CA2057780A1 CA2057780A1 CA002057780A CA2057780A CA2057780A1 CA 2057780 A1 CA2057780 A1 CA 2057780A1 CA 002057780 A CA002057780 A CA 002057780A CA 2057780 A CA2057780 A CA 2057780A CA 2057780 A1 CA2057780 A1 CA 2057780A1
- Authority
- CA
- Canada
- Prior art keywords
- layer
- temperature
- ink ribbon
- thermal transfer
- adhesive layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
- B41M5/00—Duplicating or marking methods; Sheet materials for use therein
- B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
- B41M5/40—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used characterised by the base backcoat, intermediate, or covering layers, e.g. for thermal transfer dye-donor or dye-receiver sheets; Heat, radiation filtering or absorbing means or layers; combined with other image registration layers or compositions; Special originals for reproduction by thermography
- B41M5/42—Intermediate, backcoat, or covering layers
- B41M5/44—Intermediate, backcoat, or covering layers characterised by the macromolecular compounds
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J31/00—Ink ribbons; Renovating or testing ink ribbons
- B41J31/05—Ink ribbons having coatings other than impression-material coatings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
- B41M2205/00—Printing methods or features related to printing methods; Location or type of the layers
- B41M2205/30—Thermal donors, e.g. thermal ribbons
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/913—Material designed to be responsive to temperature, light, moisture
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/914—Transfer or decalcomania
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
- Y10T428/24802—Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
- Y10T428/24843—Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.] with heat sealable or heat releasable adhesive layer
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31725—Of polyamide
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31786—Of polyester [e.g., alkyd, etc.]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31935—Ester, halide or nitrile of addition polymer
Abstract
Abstract of the Disclosure An ink ribbon for thermal transfer printer comprising a foundation and a thermal transfer layer, said thermal transfer layer comprising a colored layer containing a wax-like substance as a main component of the vehicle thereof, and a thermoplastic adhesive layer having a film-forming property provided on the surface of the colored layer, said thermoplastic adhesive layer having a melt viscosity of 1 x 104 to 5 x 106 cP at a temperature by 40°C higher than the softening temperature of the adhesive layer, a softening temperature of 45° to 90°C, a solidifying temperature of 25° to 65°C, and a temperature difference of at least 10°C between said softening temperature and said solidifying temperature. The thermal transfer ink ribbon provides clear images not only on a smooth paper but also on a rough paper even in a high-speed printing or even on printers with different peeling conditions.
Description
7 8 ~
INK RIBBON FOR THERMAL TRANSFER PRINT~R
-BACKGROUND OF THE INVENTION
The present invention relates to an ink ribbon for thermal transfer printer. More particularly, the invention relates to an ink ribbon for thermal transfer 5 printer comprising a ~oundation and a thermal trans-fer layer provided on the foundation, portions of which layer are selectively softened or melted to be transferred to a receiving medium by selectively controlling the heat generation of a plurality of heating elements provided on 10 a heating head.
The ink ribbon of such a type generally used heretofore includes one wherein a thermal transfer colored ink layer containing a wax-like substance as a main component of the vehicle of the ink is provided on a film-15 like foundation. The ink ribbon provides clear images ona smooth paper. However, there is the problem that clear images cannot be obtained on a rough paper because the ink does not reach the concave portions of the rough paper, which results in formation of transferretl ink images with 20 poor edge definition or voids.
An attempt was made wherein a thermoplastic resin having a film-forming propert~ was incorporated into the colored ink layer in addition to the wax- like substance to improve the film-~orming property of the ink 25 layer, and the ink layer was transferred on a rough paper so that the transferred ink layer spanned the concaYe portion of the rough paper where the ink did not reach, like a bridge, as sehematically sho~n in Fig. 1. In Fi~.
1, reference numerals 1, la and lb indicate a rough paper, 30 the convex portion of the paper and the concave portion of the paper, respectively. Reference numeral 2 indicates the colored ink layer transferred. The transferred ink layer 2 is adhered to the paper at the convex portions la but the ink layer 2 is out of contact with the paper at 35 the concave portion lb and spans the concave portion lb like a bridge.
INK RIBBON FOR THERMAL TRANSFER PRINT~R
-BACKGROUND OF THE INVENTION
The present invention relates to an ink ribbon for thermal transfer printer. More particularly, the invention relates to an ink ribbon for thermal transfer 5 printer comprising a ~oundation and a thermal trans-fer layer provided on the foundation, portions of which layer are selectively softened or melted to be transferred to a receiving medium by selectively controlling the heat generation of a plurality of heating elements provided on 10 a heating head.
The ink ribbon of such a type generally used heretofore includes one wherein a thermal transfer colored ink layer containing a wax-like substance as a main component of the vehicle of the ink is provided on a film-15 like foundation. The ink ribbon provides clear images ona smooth paper. However, there is the problem that clear images cannot be obtained on a rough paper because the ink does not reach the concave portions of the rough paper, which results in formation of transferretl ink images with 20 poor edge definition or voids.
An attempt was made wherein a thermoplastic resin having a film-forming propert~ was incorporated into the colored ink layer in addition to the wax- like substance to improve the film-~orming property of the ink 25 layer, and the ink layer was transferred on a rough paper so that the transferred ink layer spanned the concaYe portion of the rough paper where the ink did not reach, like a bridge, as sehematically sho~n in Fig. 1. In Fi~.
1, reference numerals 1, la and lb indicate a rough paper, 30 the convex portion of the paper and the concave portion of the paper, respectively. Reference numeral 2 indicates the colored ink layer transferred. The transferred ink layer 2 is adhered to the paper at the convex portions la but the ink layer 2 is out of contact with the paper at 35 the concave portion lb and spans the concave portion lb like a bridge.
2~57~
By means of the above technique wherein the ink layer is transferred so that it spans the concave portions of the receiving medium like a bridge, the transferred ink image is free of poor edge definition and voids, and clear 5 images can be obtained on a rough paper similarly in the case of transfer on a smooth receiving surface.
According to the above-mentioned technique utilizing the ink bridging, it was made possible to print not only on a smooth receiving paper as in the 10 conventional method but also on such a rough paper as mentioned abo~7e by means of a thermal transfer printer which resulted in a further enhancement of utility of the thermal transfer printer.
In such a situation, a printer capable of 15 printing at a high speed of about 100 cps (corresponding to a head moving ~elocity of about 260 mm/sec) or more was recently put to practical use.
In the case of such a high-speed printer, it was impossible to produce clear images on a rough paper even 20 by using the ink ribbon utilizing the ink bridging and the usable receiving paper was restricted to a smooth paper.
On the other hand, in the case of thermal transfer printers, the distance (hereinaf ter re~erred to as ~ peeling distance") between the position where some 25 portion of the ink ribb~n ;s heated with the heating head and the position where said heated portion of the ink ribbon is peeled off from the receiving paper (both positions are relative ones with respect to the heating head) or the period of time (hereinafter referred to as 30 " peeling time") between the time when some portion of the ink ribbon is heated with the heating head and the time when said heated portion is peeled off from the receiving paper (hereina~ter, the peeling distance and the peeling time are generically referred to as ~ peeling condition") 35 varies depending upon kinds of machines. IJnder the circumstances, there were some cases where an ink ribbon, which was able to provide clear images in a printer wi-th a peeling condition, was not able to provide clear images or - 3 _ 2~77~
absolutely any image in another printer with a dif ferent peeling condition.
It is an object of the present invention to provide an ink ribbon Eor thermal transfer printer capable 5 of providing clear images not only on a smooth paper but also on a rough paper even in a high-speed printing or even on printers with different peeling conditions.
This and other objects will become apparent from the description hereinafter.
SUMMARY OF THE INVENTION
The present invention provides an ink ribbon for thermal transfer printer comprising a foundation and a thermal transfer layer provided on the foundation, 15 portions of which layer are selectively softened or melted to be transferred to a receiving medium by selectively controlling the heat generation of a plurality of heating elements provided on a heating head) said thermal transfer layer comprising a colored Q layer containing a wax-like substance as a main component of the vehicle thereof, and a thermoplastic adhesive layer having a film-forming property provided on the surface of the colored layer, said thermoplastic adhesive layer having a melt 25 viscosity of 1 x 10 ' to 5 x 106 cP at a temperature by 4 0C higher than the softening temperature o~ the adhesive layer, a sof tening temperature of 4 5 to 9 0C, a solidifying temperature of 25 to 65C, and a temperature difference of at least 10C between said softening 30 temperature and said solidifying temperature.
By the use of the ink ribbon of the present invention, clear images with no defects such as poor edge definition and voids can be obtained not only on a smooth paper but also on a rough paper at printing speeds 3 5 extending between low ones and high ones or under different peeling çonditions in thermal trans-fer printers.
2 ~ 8 ~
BRIEF DESCRI_TION OF THE DRAWINGS
Fig. 1 is an explanatory view showing the state where an ink layer is transferred on a rough paper so that it spans the concave portions of the paper like a bridge.
Fig. 2 is an explanatory view showing changes in the state of an ink layer heated with a heating head in the çase of a low-speed printing.
Fig. 3 is an explanatory view showing changes in the state of an ink layer heated with a heating head in the case of a high-speed printing.
DETAILED DESCRIPTION
Owing to the thermal transfer layer composed as mentioned above in accordance with the present invention, clear images can be obtained not only on a smooth paper but also on a rough paper at printing speeds over a wide range from a low speed to a high speed, for example, from 15 cps to 150 cps (corresponding to head moving velocity of about 40 to about 400 mm/sec), and further on printers 20 with different peeling conditions.
The reason why such ef:~ects are exhibited by the above construction is not necessarily definite but is presumed as follows:
In the first placel the transfer mechanism of 25 the colored ink layer in the case that printing is carried out on a thermal tr~Lns~er printer using a conventional bridging type ink ribbon wherein a thermal transfer colored ink layer having a film-forming property is provided on a foundation.
3 0 Figs. 2 and 3 are explanatory views showing changes in the state of the ink layer after the ink ribbon is heated with a heating head. Fig. 2 shows that for a low-speed printing and Fig. 3 shows that for a high~speed printing. H indicates a time area where the ink layer is 35 supplied with heat from the heating head and the ordinate indicates the intensity of the supplied heat energy. A, B
and C indicate the states of the ink layer. A indicates the state that the ink is in a state of being softened or 2~778~
melted enough and having a property of sticking to a receiving meidum. B indicates the state that the ink, which has been once softened or melted, is again solidifying but is still in a softened state. C indicates 5 the state that the ink i9 in a state of being again solidified enough.
The investigations of the present inventors have reveaied the following: When the ink ribbon is peeled off from the recei~ing paper while the ink layer is at least 10 in state B, for instance, at peeling point Pl, the ink layer in state B sticks to the receiving paper and peels off from the foundation of the ink ribbon. However, when the ink ribbon is peeled off from the receiving paper while the ink layer is in state C, for instance, at 15 peeling point P2, the ink layer does not peel off from the foundation, because the adhesive strength between the ink layer and the foundation is again increased, which results in failure of transfer.
In the case o-f low-speed printing, the amount of 20 head energy El supplied to the ink layer from the heating head is large because of a long heating time by means of the heating head. There~ore, time t 1 that the ink layer is in state A is sufficiently long and the peeling point of the ink ribbon falls within the total time Tl of time 25 t~ and time t2 (= tl ~ t2) (hereinafter referred to as transferaMe time") for usual thermal transfer printers, which results in a good transfer.
On the other hand, in the case of high-speed printing, the heating time by means of -the heating head 30 must be reduced but the electric power per unit time input to the head cannot be increased enowgh in comlection with the life of the head, etc. Therefore, heat energy E2 supplied to the ink ribbon is smaller than heat energy El in the case of low-speed printing. This tendency is 35 marked with increasing printing speed.
Accordingly, time t3 that the ink layer is in state A is shorter than time t 1 in the case of low-speed printing, and after all transferable time Tz (= t3 + t~ ) ~77~
is shorter than time Tl.
In the case of high-speed printing, the peeling time is shortened because the run speed of the ink ribbon increases. However, since the peeling distance cannot be 5 so reduced in connection with the mechanism around the head, peeling point P3 falls within the area that the ink layer is in state C. Further the period of time that the ink layer after being melted possesses a property of sticking to the receiving paper is reduced, which results 10 in an insufficient bonding of the ink to the receiving paper. For these reasons, poor transfer occurs in the case of high speed printing.
Even in the case of low-speed printing, there are some cases that the peeling point lags behind to Pz 15 due to the mechanism around the head of a printer. In this case, poor transfer occurs even in low-speed printing because the peeling point P2 is in the area that the ink layer is in state C.
The function and effect of the present invention 20 are explained.
The thermal transfer layer according to the present inverltion has a two-layered structure composed of a colcred layer on the side of the foundation containing a wax-like substance as a main component of the vehicle and 25 a thermoplastic adhesive layer having a film-forming property provided on the colored layer.
The adhesive layer has a melt viscosity of 1 x 10~ to 5 x 106 cP (value measured at a temperature by 4 0C higher than the softening temperature), a softening 30 temperature of 45 to gaoC, a solidifying temperature of 25 to 65C9 and a temperature difference of at least 1 0C between the softening temperature and the solidifying temperature.
Thus the adhesive layer of the present invention 35 possesses a supercooling property as well as film~forming property.
Herein, the term ~ supercooling property" of the adhesive layer means the property that in the case that ~0~7~
the adhesive layer is once heated to a temperature above the softening temperature into a softened state and then cooled, the adhesive layer is not solidified but in a supercooled state even when it is cooled to the softening 5 temperature, and the adhesive layer is at last solidified when it is further cooled to a temperature below the softening temperature.
The adhesive layer thus composed possesses such a supercooling property that the adhesive layer which once 10 has been softened by heating with a heating head is not solidified by a temperature drop during a miximum travel time required -for the heated portion of the ink ribbon to travel from the position heated with the heating head to the peeling position of the ink ribbon from the receiving 15 medium. Herein, when the distance between the position of the ink ribbon heated wi-th the heating head and the peeling position of the ink ribbon is taken as ~ d" and the winding-up velocity of the ink ribbon as UV", the period of time t requried for the heated portion of the 2 0 ink ribbon to travel from the heated position to the peeling position is expressed by the equation: t = dJv.
The time t varied depending upon the structural or operational conditions of a printer. The rnaximum time t for a printer is referred to as " maximum travel time 25 (t~n~X). The maximum travel time varies depending upon kinds of machines. Generally, however~ the maximum travel time for printers put on the market at the presen-t ranges from about 2 to about 10 milliseconds.
By the use of an adhesive layer having such a 30 supercooling property as mentioned above, time t3 that the adhesive layer which has been melted or softened enough retains state A in which the adhesive layer possesses a strong stickiness to the receiving paper can be widely extended and the adhesive layer can be in state A or B
35 even at peeling point P3. When the ink ribbon is peeled off from the receiving paper even in high-speed printing, the adhesive layer is firmly adhered to the receiving paper and, therefore, is peeled off from the foundation 2~77~
together with the colored layer containing a wax-like substance as a main component of the vehicle to transfer to the receiving medium.
E~en in the case of low-speed printing, time t 1 5 that the adhesive layer retains state A can be widely extended because of its supercooling propert~. Therefore, a good transfer can be effected even though the peeling point lags behind depending upon the peeling condition of the printer used.
Further, the thermoplastic adhesive layer has a film-forming property, in a softened state, required to form clear images on a rough paper. The portion of the adhesive layer which is once softened shows a fairly weakened bonding to the adjacent portion which is not 15 heated and softened, and exhibits a strong adhesiveness to a receiving paper tiIl the softened portion is again solidified.
The thermoplastic adhesive layer as mentioned above is favorably transferred to even a rough paper 20 together with the colored layer containing a wax-like substance as a main vehicle component so that only the heated portion spans the concave portion of the rough paper like a bridge because of its film-forming property, wea~ened bonding to the adjacent portion in a solid state 25 and good adhesiveness to the receiving paper in a softened state, thereby providing clear images.
Further, in the present invention, the thermal transfer layer is constructed to have a two layered structure composed of the colored layer and the film-30 forming adhesive layer and different roles are assigned tothe respective layers. Accordingly, the film-formi~g adhesi~7e layer can be prepared to have such an adhesive formula as to fully exhibit the above-mentioned film-forming property and supercooling property. Further, the 35 ink ribbon of the present invention has the advantage that it has a good resistance to rubbing because the adhesive layer has a great strength.
Thus, the ink ribbon of the present invention 20~77&~
~ 9 can give good images even on a rough paper, complying with both the changes in peeling condition due to the increased printing speed and the different peeling conditions for kinds of machines.
The present invention will be more specifically explained.
The colored layer in the present invention is composed of a vehicle containing a wax-like substance as a main component and a coloring agent.
Examples of the wax-like substance include natural waxes such as whale wax, bees wax, lanolin, carnauba wax, candelilla wax, montan wax and ceresine wax;
petroleum waxes such as paraffin wax and microcrystalline w~x; synthetic waxes such as oxidized wax, ester wax, low 15 molecular weight polyethylene and Fischer-Tropsch wax;
higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid and behenic acid; higher aliphatic alcohols such as stearyl alcohol and behenyl alcohol; esters such as sucrose fatty acid esters, 2 0 sorbitan fatty acid esters; and amides such as oleic amide. These wax-like substances may be used singly or in admixture. Preferred wax-like substances have a melting point of 40 to 120C, particularly 65 to 85C (value meausred at a temperature rising rate of 10C /min on DSC, 25 hereinater the same). When the melting point of the wax-like substance is lower than the above range, the melting point of the colored layer becomes too low, which results in poor storage stability of the resulting ink ribbon.
When the melting point is higher than the above range, the 30 transfer sensitivty tends to be decreased.
It is preferable to use a thermoplastic resin in addition to the wax-like substane as a vehicle component for the colored layer, thereby adjusting the adhesiveness of the colored layer to the foundation. Examples of such 35 thermoplastic resins include ethylene-vinyl acetate copolymer, ethylene-alkyl (meth)acrylate copolymers, polyolefin resins, polyvinyl alcohol, vinyl acetate resins, styrene-alkyl (meth)acrylate copolymers, styrene ~0~78~
resins, saturated polyesters, ancl further synthetic rubber~like resins such as polybutene, styrene-butadiene rubber and acrylonitrile-butadiene rubber. These thermoplastic resins may be used singly or in admixture.
5 From the viewpoint of tranfer sensitivity, the resins preferably have a softening temperature o 45 to 100C, particularly 5 0 to 7 5C (the value meausred by TMA
method, hereinafter the same). The thermoplastic resin is preferably used in an amount of 5 to 50 parts by weight, particularly 10 to 25 parts by weight per 100 parts by weight of the wax-like substance. When the amount of the thermoplastic resin is lower than the above range, the transfer layer is liable to peel off from the foundation under normal conditions. When the amount of the thermoplastic resin is more than the above range, an uneven tranfer tends to occur, resulting in the formation of poor edge definition or voids in print images.
As the coloring agent for the colored layer, there can be used any coloring agent used conventionally in ink ribbons of this type, incIuding carbon black, and a variety of organic and inorganic coloring pigments and dyes. The coloring agent is suitably used in an amount of 5 to 80 parts by weight, particularly 15 to 50 parts by weight per 100 parts of the wa~-like substance.
2 5 If necessary, a variety of surface active agents or oils acting as pigm.ent dispersing agent, dispersion stabilizing agent, flowability con~rolling agent, or the like may be incorpor ated into the colored layer. Further other aclditives such as antioxidant may b~ incorporated.
Preferably the colored layer has a melting or softening temperature of 50 to 9QC, particularly 65 to 75C, and a melt viscosity of 5 x 10 to 5 ~ 103 CP, particularly 1 x 102 to 1 x 103 CP at a temperature by 4 0 C higher than the melting or softening temperature (the value measured by means of a viscoelasticity measuring and analyzing apparatus MR-300 made by Rheology Co., Ltd., hereinafter the same), from the viewpoint of securing a desi-red transfer sensitivity of the ink and a desirecl 2~77~
transfer amount of the ink. When the melting or softening temperature is lower than the above range, the resulting ink ribbon is poor in storage stability. When the melting or softening temperatue is more than the above range, the 5 transfer sensitivity tends to be lowered. When the melt viscosity is lower than the above range, the transferred ink largely spread exceeding the size of the dot of the heating head when heat is accumulated in the heating head and clear images are hardly obtained. When the melt 10 viscosity is more than the above range, an uneven transfer is liable to occur, resulting in the occurrence of poor edge definition or voids in print images.
The film-forming thermoplastic adhesive layer in the present invention has a melt viscosity of 1 x 10 4 to 15 5 x 106 cP, particularly 3 x 1~ to 2 x 106 cP at a temperature by 4 O~C higher than the softening temperature of the adhesive layer, a softening temperature of 4 5 to 90C, particularly 55 to 75C ~the value measured at a temperature rising rate of 10C /min on DSC, hereinafter 20 the same), a solidifying temperature of 25 to 65C, particularly 30 to 50C (the value measured at a temperature falling rate of 10C /min on DSC, hereinafter the same), and a temperature difference of not less than 10 C, particularly from 10 to 4 0C, more particularly 25 from 15 to 30C between the softening temperature and the solidifyirlg temperature. Such an adhesive layer possesses good film forming property and supercooling property with retaining good transfer sensitivity and storage stability.
3û When the melt viscosity of the adhesive layer is lower than the above range9 the property of transferring to a rough paper like a bridge becomes poor due to a poor film-forming property. When the melt viscosity is more than the above range, an uneven transfer occurs. In both cases, poor edge definition or voids are liable to occur in print images. YVhen the softening temperature is lower than the above range, the s torage stability of the ink ribbon is poor. When the sof-tening temper ature is ~77~
more than the above range, the transfer sensitivity is poor. When the solidifying temperature i5 less than the above range, the smearing of the receiving paper is liable to occur after printing. When the solidifying temperature is more than the above range, an uneven transfer occurs.
When the temperature difference between the softening temperature and solidifying temperature is less than the above range~ the supercooling property is poor, which results in failure to comply with the high-speed printer and the different peeling condition.
The adhesive layer is preferably composed o-f a thermoplastic material having both a film-forming property and a supercooling property and a thermoplastic material having an affinity to the above-mentioned colored layer.
The phenomenon that in transfer printing, the adhesvie layer is separated from the colored layer and the adhesive layer alone is transferred is prevented by incorporating a thermoplastic material having an affinity to the colored layer into the adhesive layer.
The thermoplastic material haYing both a film-forming property and a supercooling property (hereinafter referred to as u thermoplastic material AJ9) is thermoplastic resins such as polycaprolactones, polyamides (JP, A, 62-37392) and uns~turated polyesters (JP, ~, 62-35~84).
Polycaprolactones are preferred because of their good film-forming property and supercooling property.
Preferable polycaprolactones are those ha~ing a number average molecular weight of 8 x 103 to 1 x 105, a 30 softening temperature of 50 to 65C, a melt viscosity of 1 x 105 to 5 x 106 cP at a temperature by 40C higher than the softening temperature, a solidifying temperature of 25 to 40C and a temperature difference of 15 to 35C
between the softening temperature and the solidifying 35 temperature.
Such polycaprolactones have a good film-forming property because of their great cohesi~e force in a softened state and also a good supercooling property.
2~7780 The ollowing effects are exhibited by composing the adhesive layer of thermoplastic material A having good film-forming property and supercooling property. The image forming ability to a rough paper is good because the 5 bridge-like transfer is favorably effected due to said film-forming property and therefore clear images can be formed even on a rough paper. The portion of the adhesive layer which is attached to the surface of a receiving paper can retain its softened state for a long time due to 10 said supercooling property. Therefore, the time till the adhesiveness of the transfer layer to the receiving paper is lowered or lost can be deferred as compared with the conventional ink ribbon. For this reason, it is possible to form clear images in a high-speed printer or a variety 15 of printers with different peeling conditions. For example, it is possible to print very thin lines with a width of 0.05 mm without any poor edge definition or void even on a very rough paper having a Bekk smoothness of about 20 seconds, regardless of the printing speed or the 20 peeling condition.
With respect to the thermoplastic material having an affinity to the colored layer (hereinafter referred to as " thermoplastic material B"), there are preferably used those which are compatible with 25 thermoplastic material A and also with the vehicle of the colored layer. Generally wax-like substances are preferred.
By incorporation of a wax-like substance into the adhesive layer, a good adhesive condition between the 3 0 adhesive layer and the colored layer is kept during transfer and the colored layer is transferred in the same shape as that of the adhesive layer transferred, thereby preventing the formation of poor edge definition in print image due to the poor edge definition o f the colored 35 layer.
Wax-like substances similar to those used in the colored layer are used in the adhesive layer. A
thermoplastic resin can be used in combination with the 7 7 8 ~
wax-like subst~ce as thermoplastic material B.
Thermoplastic resins similar to those used in the colored laSrer can be used as such a thermoplastic resin for the adhesive layer. By the incorporation of the thermoplastic 5 resin, the adhesiveness of the adhesive layer to a rough paper is further improved, so that the print image formed on a rough paper is completely prevented from peeling of f from the paper and a transfer with a lesser amount of energy is made possible. When the thermoplas tic resin is 10 used in combination with the wax-like substance, the amount of the thermoplastic resin is preferably from about 0. 5 to about 2 0 parts by weight per 10 parts by weight of the wax-like substance.
Preferably thermoplastic material B has a 15 melting or softening temperature of 50 to 90C, particularly 55 to 75C from the viewpoint of transfer sensitivity or the like.
Thermoplastic material B is preferably used in an amount of 1 to 9 0 parts by weight, particularly 2 to 5 0 2 0 parts by weight per 10 parts by weight of thermoplastic material A. When the amount of thermoplastic rnaterial B
is less than the above range, the adhesiveness of the adhesive layer to the colored layer is poor and the efect of enhancing the adhesiveness to the receiving paper is 2 5 not developed. When -the amount of thermoplastic material B is more than the above range, the film-forming property and supercooling property are poor.
Into the adhesive layer, there may be incorporated other additives in addition to the above 3û mentioned components without spoiling the object of the present invention. E~amples of the additives include antioxidant (e.g. phenol derivative antioxidants such as monophenol derivative, bisphenol derivative and polymerized phenol derivatives), and heat resistance 35 improving agent used for preventing blocking occurring between the adhesive layer and the rear surface of the ink ribbon during storage of the ink ribbon in the form of a roll or pancake at elevated temperatures (e.g. body - 15 ~ ; 7 7 ~3 ~
pigments such as silica and titanium oxide, carbon black and organic pigments such as phthalocyanine blue~ fine particles of thermosetting resins such as formaldehyde resin, phenol resin ahd amino resin).
5In the present invention, a substantially transparent thermal transfer layer containing substantially no coloring agents may be interposed between the colored layer and the foundation. When such a transparent transfer layer is provided in the ink ribbon, 10 the corresponding transparent layer containing no coloring agents necessarily exists on the surface of the obtained print image. Accordingly, even when the surface of the image is rubbed with an article, there is no possibility that the coloring agent, such as pigment, contained in the 15 colored layer is attached to the article. Further, no problem occurs that the coloring agent is trans:~erred to portions of the receiving paper where no print images are formed to smear the receiving pap~r.
The transparent transfer layer is preferably 2 0 composed of a wax-like substance to obtain a good heat melt transferability and an affinity to the colored layer.
The same wax-like substances as used in the colored layer are used as the wax-like substance. The preferred i9 one or mixtures of paraffin wax, polyethylene wax, candelilla 25 wax, ester wax, carnauba wax, and the like. Into the transparent transfer layer, there may be further incorporated a thermoplastic resin which is the same as used in the colored layer, or other adhesive material, in order to control the adhesi~eness. The transparent 30 tr~nsfer layer preferably has a melting point of 65 to Other additives such as dispersi:ng agent, antioxidant, oil for viscosity control, and surface active agent may be appropriately incorporated into the 35 transparent transfer layer.
A variety of plastic films generally used as a foundation film for this type of ink ribbon, including polyester film, polyamide film and others can be used as a 20~7~
foundation in the present invention. In the case of using such plastic films, it is suitable to provide on the rear surface of the foundation (the surface in sliding contact with the heating head) a conventional stick pre~renting 5 layer composed of silicone resin, fluorine-containing resin or nitrocellulose, or mixtures of the foregoing resins with lubricating materials, in order to prevent the foundation from sticking to the heating head. High density thin papers such as condenser paper can also be 10 used as the foundation. The thickness of the fouxldation is preferably from 1 to 9 ,u m, more preferably from 2 to 4.5 ,u m in order to obtain a good heat conduction.
The ink ribbon of the present invention can be produced by optionally forming a transparent transfer layer by solvent coating method or hot melt coating method, forming a colored layer thereon by solvent coating method or hot melt coating method, and forming an adhesive layer thereon by solYent coating method. The thickness of the colored layer is preferably from 0.5 to 10 ~ m, more preferably 1 to 5 ,u m. The thiclsness of the adhesive layer is preferably from 0.3 to 5,u m, more preferably 0.5 to 2.5 ,u m. The thickness of the transparent tranfer layer is preferably from 0.1 to 5 ,u m, more preferahly from 0.5 to 3 ,u rn.
In the present invention! either a thermal transfer layer with single color may be formed on single foundation, or a plurality of thermal transfer layers with different colors (e.g. yellow, cyan and magenta, and optionally black) may be formed on single foundation in a 30 side-b~side relationship.
In the case of printing using the ink ribbon of the present invent~on, clear images can be formed on any paper so long as it has a E3ekk smoothness of not less than about 10 seconds, regardless of kinds of paper, e.g. bond 35 paper1 paper for PPC and paper for thermal transfer. Of course, clear images can be obtained on smooth plastic films.
The present invention is more speci Eically 2~77~
described and explained by means of the following Examples. It is to be understood that the present invention is not limited to the Examples, and various change and modifications may be made in the invention 5 without departing from the spirit and scope thereof.
Examples 1 to 5 and Comparative Example 1 Onto the front surface of polyethylene terephthalate ~ilm having a thickness of 3.5 ,u m pro~ided 10 with a stick-preventing layer having a thickness of 0.2,u m composed of silicone resin on the rear surface thereof was applied the composition shown in Table 1 by solvent coating and dried to give a colored layer having the physical properties shown in Table 1.
Each composition shown in Table 2 was applied onto the colored layer by solverlt coating and dried to give an adhesive layer having the physical properties shown in Table 2. In the case of Example 5, the composition shown in Table 3 was applied onto the above 2 0 polyethylene terephthalate film by solvent coating and dried to giYe a transparent transfer l~yer having the physical properties shown in Table 3, followed by the successive formation of the colored layer and the adhesiv layer.
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Employing each of the ink ribbons obtained above, printing tests were conducted on the thermal transfer printers mantioned below under the conditions shown in Table 4.
Low-speed printer: WD-652 (30 cps) made by Sharp Corporation Medium-speed printer: Ul Pro 501 ~45 cps) made by lû Matsushita Electric Industrial Co., Ltd.
High-speed printer: Ul Pro 503 AI (75 cps) made by Matsushita Electric Industrial Co., 1 5 Ltd.
The number of dots per one character was 4 8 for every printer. Paper for thermal transfer (Bel~k smoothness: 600 seconds), paper for PPC (Bekk smoothness:
2 0 5 0 seconds) and bond paper (Bekk s~r.oothness: 10 seconds) were used as the receiving paper.
The clearness and the void or poor edge definition were e~a~uated with -the images obtained on the receiving paper according to the evaluation method 25 mentioned below. The results thereof are shown in Table 5.
A. Clearness One dot printing was carried out. The ratio of 3 0 the area of one dot of the ink actually printed to the area of one dot, i. e. one heating element, of the heatillg head was determined. The obtained values were graded into five classes as mentioned below.
35 5 - Area ratio: 0.95 to 1.05 4 Area ratio: not less than 0.85, less than 0.95 3 Area ratio: not less than 0.75, less than 0.85 2 Area ratio: not less than 0.55, less than 0.75 2~778~
Area ratio: less than 0.55 B. Yoid or poor edge definition Solid-printing was carried out. The optical 5 density (OD value) of the printed paper was measured at the predetermined fi~e positions and the average ~alue was obtained. The values were graded into five classes as mentioned belowO
10 5 - OD value: ;not less than 1.5 4 OD value: not less than 1.2, less than 1.5 3 OD value: not less than 0.9, less than 1.2 2 - OD value: not less than 0.6, less than 0.9 1 OD value: less than 0.6 2~77~
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¢ L~ L~ LO ~ c~
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As is clear from the results shown in Table 5, Examples 1 and 5 provided a high quality of images with no void and no poor edge definition not only on the smooth paper but also on the bond paper at every one of low 5 speed, medium speed and high speed.
Examples 2 to 4 provided almost satisfactory results, which were a little inferior to those obtained in Examples 1 and 5.
In contrast thereto, the images obtained in 10 Comparative Example 1 were poor in clearness and contained remarkable voids and poor edge definition. Poor results were obtained especially in the case of the high-speed printing or the printing on the bond paper.
With respect to Example 5, even though the 15 images on the receiving paper were rubbed with another receiving paper, it was not stained. Further, any stain did not occur which was caused due to the phenomenon that the coloring agent contained in the print image was transferred to portions of the receiving paper where no 20 images were formed.
In addition to the materials and i ngredients used in the Examples, other materials and ingredients can be used in the Examples as set forth in the specification to obtain substantially the same results.
By means of the above technique wherein the ink layer is transferred so that it spans the concave portions of the receiving medium like a bridge, the transferred ink image is free of poor edge definition and voids, and clear 5 images can be obtained on a rough paper similarly in the case of transfer on a smooth receiving surface.
According to the above-mentioned technique utilizing the ink bridging, it was made possible to print not only on a smooth receiving paper as in the 10 conventional method but also on such a rough paper as mentioned abo~7e by means of a thermal transfer printer which resulted in a further enhancement of utility of the thermal transfer printer.
In such a situation, a printer capable of 15 printing at a high speed of about 100 cps (corresponding to a head moving ~elocity of about 260 mm/sec) or more was recently put to practical use.
In the case of such a high-speed printer, it was impossible to produce clear images on a rough paper even 20 by using the ink ribbon utilizing the ink bridging and the usable receiving paper was restricted to a smooth paper.
On the other hand, in the case of thermal transfer printers, the distance (hereinaf ter re~erred to as ~ peeling distance") between the position where some 25 portion of the ink ribb~n ;s heated with the heating head and the position where said heated portion of the ink ribbon is peeled off from the receiving paper (both positions are relative ones with respect to the heating head) or the period of time (hereinafter referred to as 30 " peeling time") between the time when some portion of the ink ribbon is heated with the heating head and the time when said heated portion is peeled off from the receiving paper (hereina~ter, the peeling distance and the peeling time are generically referred to as ~ peeling condition") 35 varies depending upon kinds of machines. IJnder the circumstances, there were some cases where an ink ribbon, which was able to provide clear images in a printer wi-th a peeling condition, was not able to provide clear images or - 3 _ 2~77~
absolutely any image in another printer with a dif ferent peeling condition.
It is an object of the present invention to provide an ink ribbon Eor thermal transfer printer capable 5 of providing clear images not only on a smooth paper but also on a rough paper even in a high-speed printing or even on printers with different peeling conditions.
This and other objects will become apparent from the description hereinafter.
SUMMARY OF THE INVENTION
The present invention provides an ink ribbon for thermal transfer printer comprising a foundation and a thermal transfer layer provided on the foundation, 15 portions of which layer are selectively softened or melted to be transferred to a receiving medium by selectively controlling the heat generation of a plurality of heating elements provided on a heating head) said thermal transfer layer comprising a colored Q layer containing a wax-like substance as a main component of the vehicle thereof, and a thermoplastic adhesive layer having a film-forming property provided on the surface of the colored layer, said thermoplastic adhesive layer having a melt 25 viscosity of 1 x 10 ' to 5 x 106 cP at a temperature by 4 0C higher than the softening temperature o~ the adhesive layer, a sof tening temperature of 4 5 to 9 0C, a solidifying temperature of 25 to 65C, and a temperature difference of at least 10C between said softening 30 temperature and said solidifying temperature.
By the use of the ink ribbon of the present invention, clear images with no defects such as poor edge definition and voids can be obtained not only on a smooth paper but also on a rough paper at printing speeds 3 5 extending between low ones and high ones or under different peeling çonditions in thermal trans-fer printers.
2 ~ 8 ~
BRIEF DESCRI_TION OF THE DRAWINGS
Fig. 1 is an explanatory view showing the state where an ink layer is transferred on a rough paper so that it spans the concave portions of the paper like a bridge.
Fig. 2 is an explanatory view showing changes in the state of an ink layer heated with a heating head in the çase of a low-speed printing.
Fig. 3 is an explanatory view showing changes in the state of an ink layer heated with a heating head in the case of a high-speed printing.
DETAILED DESCRIPTION
Owing to the thermal transfer layer composed as mentioned above in accordance with the present invention, clear images can be obtained not only on a smooth paper but also on a rough paper at printing speeds over a wide range from a low speed to a high speed, for example, from 15 cps to 150 cps (corresponding to head moving velocity of about 40 to about 400 mm/sec), and further on printers 20 with different peeling conditions.
The reason why such ef:~ects are exhibited by the above construction is not necessarily definite but is presumed as follows:
In the first placel the transfer mechanism of 25 the colored ink layer in the case that printing is carried out on a thermal tr~Lns~er printer using a conventional bridging type ink ribbon wherein a thermal transfer colored ink layer having a film-forming property is provided on a foundation.
3 0 Figs. 2 and 3 are explanatory views showing changes in the state of the ink layer after the ink ribbon is heated with a heating head. Fig. 2 shows that for a low-speed printing and Fig. 3 shows that for a high~speed printing. H indicates a time area where the ink layer is 35 supplied with heat from the heating head and the ordinate indicates the intensity of the supplied heat energy. A, B
and C indicate the states of the ink layer. A indicates the state that the ink is in a state of being softened or 2~778~
melted enough and having a property of sticking to a receiving meidum. B indicates the state that the ink, which has been once softened or melted, is again solidifying but is still in a softened state. C indicates 5 the state that the ink i9 in a state of being again solidified enough.
The investigations of the present inventors have reveaied the following: When the ink ribbon is peeled off from the recei~ing paper while the ink layer is at least 10 in state B, for instance, at peeling point Pl, the ink layer in state B sticks to the receiving paper and peels off from the foundation of the ink ribbon. However, when the ink ribbon is peeled off from the receiving paper while the ink layer is in state C, for instance, at 15 peeling point P2, the ink layer does not peel off from the foundation, because the adhesive strength between the ink layer and the foundation is again increased, which results in failure of transfer.
In the case o-f low-speed printing, the amount of 20 head energy El supplied to the ink layer from the heating head is large because of a long heating time by means of the heating head. There~ore, time t 1 that the ink layer is in state A is sufficiently long and the peeling point of the ink ribbon falls within the total time Tl of time 25 t~ and time t2 (= tl ~ t2) (hereinafter referred to as transferaMe time") for usual thermal transfer printers, which results in a good transfer.
On the other hand, in the case of high-speed printing, the heating time by means of -the heating head 30 must be reduced but the electric power per unit time input to the head cannot be increased enowgh in comlection with the life of the head, etc. Therefore, heat energy E2 supplied to the ink ribbon is smaller than heat energy El in the case of low-speed printing. This tendency is 35 marked with increasing printing speed.
Accordingly, time t3 that the ink layer is in state A is shorter than time t 1 in the case of low-speed printing, and after all transferable time Tz (= t3 + t~ ) ~77~
is shorter than time Tl.
In the case of high-speed printing, the peeling time is shortened because the run speed of the ink ribbon increases. However, since the peeling distance cannot be 5 so reduced in connection with the mechanism around the head, peeling point P3 falls within the area that the ink layer is in state C. Further the period of time that the ink layer after being melted possesses a property of sticking to the receiving paper is reduced, which results 10 in an insufficient bonding of the ink to the receiving paper. For these reasons, poor transfer occurs in the case of high speed printing.
Even in the case of low-speed printing, there are some cases that the peeling point lags behind to Pz 15 due to the mechanism around the head of a printer. In this case, poor transfer occurs even in low-speed printing because the peeling point P2 is in the area that the ink layer is in state C.
The function and effect of the present invention 20 are explained.
The thermal transfer layer according to the present inverltion has a two-layered structure composed of a colcred layer on the side of the foundation containing a wax-like substance as a main component of the vehicle and 25 a thermoplastic adhesive layer having a film-forming property provided on the colored layer.
The adhesive layer has a melt viscosity of 1 x 10~ to 5 x 106 cP (value measured at a temperature by 4 0C higher than the softening temperature), a softening 30 temperature of 45 to gaoC, a solidifying temperature of 25 to 65C9 and a temperature difference of at least 1 0C between the softening temperature and the solidifying temperature.
Thus the adhesive layer of the present invention 35 possesses a supercooling property as well as film~forming property.
Herein, the term ~ supercooling property" of the adhesive layer means the property that in the case that ~0~7~
the adhesive layer is once heated to a temperature above the softening temperature into a softened state and then cooled, the adhesive layer is not solidified but in a supercooled state even when it is cooled to the softening 5 temperature, and the adhesive layer is at last solidified when it is further cooled to a temperature below the softening temperature.
The adhesive layer thus composed possesses such a supercooling property that the adhesive layer which once 10 has been softened by heating with a heating head is not solidified by a temperature drop during a miximum travel time required -for the heated portion of the ink ribbon to travel from the position heated with the heating head to the peeling position of the ink ribbon from the receiving 15 medium. Herein, when the distance between the position of the ink ribbon heated wi-th the heating head and the peeling position of the ink ribbon is taken as ~ d" and the winding-up velocity of the ink ribbon as UV", the period of time t requried for the heated portion of the 2 0 ink ribbon to travel from the heated position to the peeling position is expressed by the equation: t = dJv.
The time t varied depending upon the structural or operational conditions of a printer. The rnaximum time t for a printer is referred to as " maximum travel time 25 (t~n~X). The maximum travel time varies depending upon kinds of machines. Generally, however~ the maximum travel time for printers put on the market at the presen-t ranges from about 2 to about 10 milliseconds.
By the use of an adhesive layer having such a 30 supercooling property as mentioned above, time t3 that the adhesive layer which has been melted or softened enough retains state A in which the adhesive layer possesses a strong stickiness to the receiving paper can be widely extended and the adhesive layer can be in state A or B
35 even at peeling point P3. When the ink ribbon is peeled off from the receiving paper even in high-speed printing, the adhesive layer is firmly adhered to the receiving paper and, therefore, is peeled off from the foundation 2~77~
together with the colored layer containing a wax-like substance as a main component of the vehicle to transfer to the receiving medium.
E~en in the case of low-speed printing, time t 1 5 that the adhesive layer retains state A can be widely extended because of its supercooling propert~. Therefore, a good transfer can be effected even though the peeling point lags behind depending upon the peeling condition of the printer used.
Further, the thermoplastic adhesive layer has a film-forming property, in a softened state, required to form clear images on a rough paper. The portion of the adhesive layer which is once softened shows a fairly weakened bonding to the adjacent portion which is not 15 heated and softened, and exhibits a strong adhesiveness to a receiving paper tiIl the softened portion is again solidified.
The thermoplastic adhesive layer as mentioned above is favorably transferred to even a rough paper 20 together with the colored layer containing a wax-like substance as a main vehicle component so that only the heated portion spans the concave portion of the rough paper like a bridge because of its film-forming property, wea~ened bonding to the adjacent portion in a solid state 25 and good adhesiveness to the receiving paper in a softened state, thereby providing clear images.
Further, in the present invention, the thermal transfer layer is constructed to have a two layered structure composed of the colored layer and the film-30 forming adhesive layer and different roles are assigned tothe respective layers. Accordingly, the film-formi~g adhesi~7e layer can be prepared to have such an adhesive formula as to fully exhibit the above-mentioned film-forming property and supercooling property. Further, the 35 ink ribbon of the present invention has the advantage that it has a good resistance to rubbing because the adhesive layer has a great strength.
Thus, the ink ribbon of the present invention 20~77&~
~ 9 can give good images even on a rough paper, complying with both the changes in peeling condition due to the increased printing speed and the different peeling conditions for kinds of machines.
The present invention will be more specifically explained.
The colored layer in the present invention is composed of a vehicle containing a wax-like substance as a main component and a coloring agent.
Examples of the wax-like substance include natural waxes such as whale wax, bees wax, lanolin, carnauba wax, candelilla wax, montan wax and ceresine wax;
petroleum waxes such as paraffin wax and microcrystalline w~x; synthetic waxes such as oxidized wax, ester wax, low 15 molecular weight polyethylene and Fischer-Tropsch wax;
higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid and behenic acid; higher aliphatic alcohols such as stearyl alcohol and behenyl alcohol; esters such as sucrose fatty acid esters, 2 0 sorbitan fatty acid esters; and amides such as oleic amide. These wax-like substances may be used singly or in admixture. Preferred wax-like substances have a melting point of 40 to 120C, particularly 65 to 85C (value meausred at a temperature rising rate of 10C /min on DSC, 25 hereinater the same). When the melting point of the wax-like substance is lower than the above range, the melting point of the colored layer becomes too low, which results in poor storage stability of the resulting ink ribbon.
When the melting point is higher than the above range, the 30 transfer sensitivty tends to be decreased.
It is preferable to use a thermoplastic resin in addition to the wax-like substane as a vehicle component for the colored layer, thereby adjusting the adhesiveness of the colored layer to the foundation. Examples of such 35 thermoplastic resins include ethylene-vinyl acetate copolymer, ethylene-alkyl (meth)acrylate copolymers, polyolefin resins, polyvinyl alcohol, vinyl acetate resins, styrene-alkyl (meth)acrylate copolymers, styrene ~0~78~
resins, saturated polyesters, ancl further synthetic rubber~like resins such as polybutene, styrene-butadiene rubber and acrylonitrile-butadiene rubber. These thermoplastic resins may be used singly or in admixture.
5 From the viewpoint of tranfer sensitivity, the resins preferably have a softening temperature o 45 to 100C, particularly 5 0 to 7 5C (the value meausred by TMA
method, hereinafter the same). The thermoplastic resin is preferably used in an amount of 5 to 50 parts by weight, particularly 10 to 25 parts by weight per 100 parts by weight of the wax-like substance. When the amount of the thermoplastic resin is lower than the above range, the transfer layer is liable to peel off from the foundation under normal conditions. When the amount of the thermoplastic resin is more than the above range, an uneven tranfer tends to occur, resulting in the formation of poor edge definition or voids in print images.
As the coloring agent for the colored layer, there can be used any coloring agent used conventionally in ink ribbons of this type, incIuding carbon black, and a variety of organic and inorganic coloring pigments and dyes. The coloring agent is suitably used in an amount of 5 to 80 parts by weight, particularly 15 to 50 parts by weight per 100 parts of the wa~-like substance.
2 5 If necessary, a variety of surface active agents or oils acting as pigm.ent dispersing agent, dispersion stabilizing agent, flowability con~rolling agent, or the like may be incorpor ated into the colored layer. Further other aclditives such as antioxidant may b~ incorporated.
Preferably the colored layer has a melting or softening temperature of 50 to 9QC, particularly 65 to 75C, and a melt viscosity of 5 x 10 to 5 ~ 103 CP, particularly 1 x 102 to 1 x 103 CP at a temperature by 4 0 C higher than the melting or softening temperature (the value measured by means of a viscoelasticity measuring and analyzing apparatus MR-300 made by Rheology Co., Ltd., hereinafter the same), from the viewpoint of securing a desi-red transfer sensitivity of the ink and a desirecl 2~77~
transfer amount of the ink. When the melting or softening temperature is lower than the above range, the resulting ink ribbon is poor in storage stability. When the melting or softening temperatue is more than the above range, the 5 transfer sensitivity tends to be lowered. When the melt viscosity is lower than the above range, the transferred ink largely spread exceeding the size of the dot of the heating head when heat is accumulated in the heating head and clear images are hardly obtained. When the melt 10 viscosity is more than the above range, an uneven transfer is liable to occur, resulting in the occurrence of poor edge definition or voids in print images.
The film-forming thermoplastic adhesive layer in the present invention has a melt viscosity of 1 x 10 4 to 15 5 x 106 cP, particularly 3 x 1~ to 2 x 106 cP at a temperature by 4 O~C higher than the softening temperature of the adhesive layer, a softening temperature of 4 5 to 90C, particularly 55 to 75C ~the value measured at a temperature rising rate of 10C /min on DSC, hereinafter 20 the same), a solidifying temperature of 25 to 65C, particularly 30 to 50C (the value measured at a temperature falling rate of 10C /min on DSC, hereinafter the same), and a temperature difference of not less than 10 C, particularly from 10 to 4 0C, more particularly 25 from 15 to 30C between the softening temperature and the solidifyirlg temperature. Such an adhesive layer possesses good film forming property and supercooling property with retaining good transfer sensitivity and storage stability.
3û When the melt viscosity of the adhesive layer is lower than the above range9 the property of transferring to a rough paper like a bridge becomes poor due to a poor film-forming property. When the melt viscosity is more than the above range, an uneven transfer occurs. In both cases, poor edge definition or voids are liable to occur in print images. YVhen the softening temperature is lower than the above range, the s torage stability of the ink ribbon is poor. When the sof-tening temper ature is ~77~
more than the above range, the transfer sensitivity is poor. When the solidifying temperature i5 less than the above range, the smearing of the receiving paper is liable to occur after printing. When the solidifying temperature is more than the above range, an uneven transfer occurs.
When the temperature difference between the softening temperature and solidifying temperature is less than the above range~ the supercooling property is poor, which results in failure to comply with the high-speed printer and the different peeling condition.
The adhesive layer is preferably composed o-f a thermoplastic material having both a film-forming property and a supercooling property and a thermoplastic material having an affinity to the above-mentioned colored layer.
The phenomenon that in transfer printing, the adhesvie layer is separated from the colored layer and the adhesive layer alone is transferred is prevented by incorporating a thermoplastic material having an affinity to the colored layer into the adhesive layer.
The thermoplastic material haYing both a film-forming property and a supercooling property (hereinafter referred to as u thermoplastic material AJ9) is thermoplastic resins such as polycaprolactones, polyamides (JP, A, 62-37392) and uns~turated polyesters (JP, ~, 62-35~84).
Polycaprolactones are preferred because of their good film-forming property and supercooling property.
Preferable polycaprolactones are those ha~ing a number average molecular weight of 8 x 103 to 1 x 105, a 30 softening temperature of 50 to 65C, a melt viscosity of 1 x 105 to 5 x 106 cP at a temperature by 40C higher than the softening temperature, a solidifying temperature of 25 to 40C and a temperature difference of 15 to 35C
between the softening temperature and the solidifying 35 temperature.
Such polycaprolactones have a good film-forming property because of their great cohesi~e force in a softened state and also a good supercooling property.
2~7780 The ollowing effects are exhibited by composing the adhesive layer of thermoplastic material A having good film-forming property and supercooling property. The image forming ability to a rough paper is good because the 5 bridge-like transfer is favorably effected due to said film-forming property and therefore clear images can be formed even on a rough paper. The portion of the adhesive layer which is attached to the surface of a receiving paper can retain its softened state for a long time due to 10 said supercooling property. Therefore, the time till the adhesiveness of the transfer layer to the receiving paper is lowered or lost can be deferred as compared with the conventional ink ribbon. For this reason, it is possible to form clear images in a high-speed printer or a variety 15 of printers with different peeling conditions. For example, it is possible to print very thin lines with a width of 0.05 mm without any poor edge definition or void even on a very rough paper having a Bekk smoothness of about 20 seconds, regardless of the printing speed or the 20 peeling condition.
With respect to the thermoplastic material having an affinity to the colored layer (hereinafter referred to as " thermoplastic material B"), there are preferably used those which are compatible with 25 thermoplastic material A and also with the vehicle of the colored layer. Generally wax-like substances are preferred.
By incorporation of a wax-like substance into the adhesive layer, a good adhesive condition between the 3 0 adhesive layer and the colored layer is kept during transfer and the colored layer is transferred in the same shape as that of the adhesive layer transferred, thereby preventing the formation of poor edge definition in print image due to the poor edge definition o f the colored 35 layer.
Wax-like substances similar to those used in the colored layer are used in the adhesive layer. A
thermoplastic resin can be used in combination with the 7 7 8 ~
wax-like subst~ce as thermoplastic material B.
Thermoplastic resins similar to those used in the colored laSrer can be used as such a thermoplastic resin for the adhesive layer. By the incorporation of the thermoplastic 5 resin, the adhesiveness of the adhesive layer to a rough paper is further improved, so that the print image formed on a rough paper is completely prevented from peeling of f from the paper and a transfer with a lesser amount of energy is made possible. When the thermoplas tic resin is 10 used in combination with the wax-like substance, the amount of the thermoplastic resin is preferably from about 0. 5 to about 2 0 parts by weight per 10 parts by weight of the wax-like substance.
Preferably thermoplastic material B has a 15 melting or softening temperature of 50 to 90C, particularly 55 to 75C from the viewpoint of transfer sensitivity or the like.
Thermoplastic material B is preferably used in an amount of 1 to 9 0 parts by weight, particularly 2 to 5 0 2 0 parts by weight per 10 parts by weight of thermoplastic material A. When the amount of thermoplastic rnaterial B
is less than the above range, the adhesiveness of the adhesive layer to the colored layer is poor and the efect of enhancing the adhesiveness to the receiving paper is 2 5 not developed. When -the amount of thermoplastic material B is more than the above range, the film-forming property and supercooling property are poor.
Into the adhesive layer, there may be incorporated other additives in addition to the above 3û mentioned components without spoiling the object of the present invention. E~amples of the additives include antioxidant (e.g. phenol derivative antioxidants such as monophenol derivative, bisphenol derivative and polymerized phenol derivatives), and heat resistance 35 improving agent used for preventing blocking occurring between the adhesive layer and the rear surface of the ink ribbon during storage of the ink ribbon in the form of a roll or pancake at elevated temperatures (e.g. body - 15 ~ ; 7 7 ~3 ~
pigments such as silica and titanium oxide, carbon black and organic pigments such as phthalocyanine blue~ fine particles of thermosetting resins such as formaldehyde resin, phenol resin ahd amino resin).
5In the present invention, a substantially transparent thermal transfer layer containing substantially no coloring agents may be interposed between the colored layer and the foundation. When such a transparent transfer layer is provided in the ink ribbon, 10 the corresponding transparent layer containing no coloring agents necessarily exists on the surface of the obtained print image. Accordingly, even when the surface of the image is rubbed with an article, there is no possibility that the coloring agent, such as pigment, contained in the 15 colored layer is attached to the article. Further, no problem occurs that the coloring agent is trans:~erred to portions of the receiving paper where no print images are formed to smear the receiving pap~r.
The transparent transfer layer is preferably 2 0 composed of a wax-like substance to obtain a good heat melt transferability and an affinity to the colored layer.
The same wax-like substances as used in the colored layer are used as the wax-like substance. The preferred i9 one or mixtures of paraffin wax, polyethylene wax, candelilla 25 wax, ester wax, carnauba wax, and the like. Into the transparent transfer layer, there may be further incorporated a thermoplastic resin which is the same as used in the colored layer, or other adhesive material, in order to control the adhesi~eness. The transparent 30 tr~nsfer layer preferably has a melting point of 65 to Other additives such as dispersi:ng agent, antioxidant, oil for viscosity control, and surface active agent may be appropriately incorporated into the 35 transparent transfer layer.
A variety of plastic films generally used as a foundation film for this type of ink ribbon, including polyester film, polyamide film and others can be used as a 20~7~
foundation in the present invention. In the case of using such plastic films, it is suitable to provide on the rear surface of the foundation (the surface in sliding contact with the heating head) a conventional stick pre~renting 5 layer composed of silicone resin, fluorine-containing resin or nitrocellulose, or mixtures of the foregoing resins with lubricating materials, in order to prevent the foundation from sticking to the heating head. High density thin papers such as condenser paper can also be 10 used as the foundation. The thickness of the fouxldation is preferably from 1 to 9 ,u m, more preferably from 2 to 4.5 ,u m in order to obtain a good heat conduction.
The ink ribbon of the present invention can be produced by optionally forming a transparent transfer layer by solvent coating method or hot melt coating method, forming a colored layer thereon by solvent coating method or hot melt coating method, and forming an adhesive layer thereon by solYent coating method. The thickness of the colored layer is preferably from 0.5 to 10 ~ m, more preferably 1 to 5 ,u m. The thiclsness of the adhesive layer is preferably from 0.3 to 5,u m, more preferably 0.5 to 2.5 ,u m. The thickness of the transparent tranfer layer is preferably from 0.1 to 5 ,u m, more preferahly from 0.5 to 3 ,u rn.
In the present invention! either a thermal transfer layer with single color may be formed on single foundation, or a plurality of thermal transfer layers with different colors (e.g. yellow, cyan and magenta, and optionally black) may be formed on single foundation in a 30 side-b~side relationship.
In the case of printing using the ink ribbon of the present invent~on, clear images can be formed on any paper so long as it has a E3ekk smoothness of not less than about 10 seconds, regardless of kinds of paper, e.g. bond 35 paper1 paper for PPC and paper for thermal transfer. Of course, clear images can be obtained on smooth plastic films.
The present invention is more speci Eically 2~77~
described and explained by means of the following Examples. It is to be understood that the present invention is not limited to the Examples, and various change and modifications may be made in the invention 5 without departing from the spirit and scope thereof.
Examples 1 to 5 and Comparative Example 1 Onto the front surface of polyethylene terephthalate ~ilm having a thickness of 3.5 ,u m pro~ided 10 with a stick-preventing layer having a thickness of 0.2,u m composed of silicone resin on the rear surface thereof was applied the composition shown in Table 1 by solvent coating and dried to give a colored layer having the physical properties shown in Table 1.
Each composition shown in Table 2 was applied onto the colored layer by solverlt coating and dried to give an adhesive layer having the physical properties shown in Table 2. In the case of Example 5, the composition shown in Table 3 was applied onto the above 2 0 polyethylene terephthalate film by solvent coating and dried to giYe a transparent transfer l~yer having the physical properties shown in Table 3, followed by the successive formation of the colored layer and the adhesiv layer.
%~7~
~ ~ o 2~57~g~
_ ~ ~ ~ o ~7 ~ CD ~ O ~ X
~ . o~
~ ~ - O ~,^ Ov^
, o O ~ ~¢ .
o C`~ C~ ¢ CQ C~ Lt~ ~ oV ~ o ~ d ~
c~ ~ o o LL~ ~ - X ~3 o ~ O _ ~ ,o ~ t~
_ o ~ ~
¢ ~ ~ ~ O ~ ~ ~
,~ O o ~ ~ D ~
O~ ~ ~ ~ ~ b y :~! b y a ~
e-- ~ ~Ov oO
o ~, ~ D ~ D e S3 ~ S
20~77~
~ 20 ~, U~ ~
20~77~
Employing each of the ink ribbons obtained above, printing tests were conducted on the thermal transfer printers mantioned below under the conditions shown in Table 4.
Low-speed printer: WD-652 (30 cps) made by Sharp Corporation Medium-speed printer: Ul Pro 501 ~45 cps) made by lû Matsushita Electric Industrial Co., Ltd.
High-speed printer: Ul Pro 503 AI (75 cps) made by Matsushita Electric Industrial Co., 1 5 Ltd.
The number of dots per one character was 4 8 for every printer. Paper for thermal transfer (Bel~k smoothness: 600 seconds), paper for PPC (Bekk smoothness:
2 0 5 0 seconds) and bond paper (Bekk s~r.oothness: 10 seconds) were used as the receiving paper.
The clearness and the void or poor edge definition were e~a~uated with -the images obtained on the receiving paper according to the evaluation method 25 mentioned below. The results thereof are shown in Table 5.
A. Clearness One dot printing was carried out. The ratio of 3 0 the area of one dot of the ink actually printed to the area of one dot, i. e. one heating element, of the heatillg head was determined. The obtained values were graded into five classes as mentioned below.
35 5 - Area ratio: 0.95 to 1.05 4 Area ratio: not less than 0.85, less than 0.95 3 Area ratio: not less than 0.75, less than 0.85 2 Area ratio: not less than 0.55, less than 0.75 2~778~
Area ratio: less than 0.55 B. Yoid or poor edge definition Solid-printing was carried out. The optical 5 density (OD value) of the printed paper was measured at the predetermined fi~e positions and the average ~alue was obtained. The values were graded into five classes as mentioned belowO
10 5 - OD value: ;not less than 1.5 4 OD value: not less than 1.2, less than 1.5 3 OD value: not less than 0.9, less than 1.2 2 - OD value: not less than 0.6, less than 0.9 1 OD value: less than 0.6 2~77~
~ 23 ~ o .
~ ) ~
a~ G ~ ~
2~77~
1¢
.~ 1~ oL~ L~
P
I ~
I¢
LC~L~LO Lf~L~L~
L ~ ~ ~
~ c~ a:~ Lt~ er ct~ L~ ~ ~ Lt~
¢ L~ L~ LO ~ c~
LO L~ ~r L~
1~ Ll~L~ L~L~r L~Lt~
~ ~ ~
.~ o o ~ ~o o ~ ~ o ~
~ h ~
~o ~ ~ o.
v~ 3 ~ . ;z; ~ ~
~0~77~
As is clear from the results shown in Table 5, Examples 1 and 5 provided a high quality of images with no void and no poor edge definition not only on the smooth paper but also on the bond paper at every one of low 5 speed, medium speed and high speed.
Examples 2 to 4 provided almost satisfactory results, which were a little inferior to those obtained in Examples 1 and 5.
In contrast thereto, the images obtained in 10 Comparative Example 1 were poor in clearness and contained remarkable voids and poor edge definition. Poor results were obtained especially in the case of the high-speed printing or the printing on the bond paper.
With respect to Example 5, even though the 15 images on the receiving paper were rubbed with another receiving paper, it was not stained. Further, any stain did not occur which was caused due to the phenomenon that the coloring agent contained in the print image was transferred to portions of the receiving paper where no 20 images were formed.
In addition to the materials and i ngredients used in the Examples, other materials and ingredients can be used in the Examples as set forth in the specification to obtain substantially the same results.
Claims (5)
1. An ink ribbon for thermal transfer printer comprising a foundation and a thermal transfer layer provided on the foundation, portions of which layer are selectively softened or melted to be transferred to a receiving medium by selectively controlling the heat generation of a plurality of heating elements provided on a heating head, said thermal transfer layer comprising a colored layer containing a wax like substance as a main component of the vehicle thereof, and a thermoplastic adhesive layer having a film-forming property provided on the surface of the colored layer, said thermoplastic adhesive layer having a melt viscosity of 1 x 104 to 5 x 106 cP at a temperature by 40°C higher than the softening temperature of the adhesive layer, a softening temperature of 45° to 90°C, a solidifying temperature of 25° to 65°C, and a temperature difference of at least 10°C between said softening temperature and said solidifying temperature.
2. The ink ribbon of Claim 1, wherein said thermoplastic adhesive layer comprises a thermoplastic material having an affinity to said colored layer and a polycaprolactone.
3. The ink ribbon of Claim 2, wherein said polycaprolactone has a number average molecular weight of 8 x 103 to 1 x 105, a softening temperature of 50° to 65°C, a melt viscosity of 1 x 105 to 5 x 106 cP at a temperature by 40°C higher than the softening temperature, a solidifying temperature of 25° to 40°C and a temperature difference of 15° to 35°C between the softening temperature and the solidifying temperature.
4. The ink ribbon of Claim 2, wherein said thermoplastic material having to an affinity to said colored layer is a wax-like substance.
5. The ink ribbon of Claim 1, which further has a substantially transparent thermal transfer layer containing substantially no coloring agent interposed between said colored layer and said foundation.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2405177A JP3025311B2 (en) | 1990-12-21 | 1990-12-21 | Ink ribbon for thermal transfer printer |
| JP405177/1990 | 1990-12-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2057780A1 true CA2057780A1 (en) | 1992-06-22 |
Family
ID=18514806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002057780A Abandoned CA2057780A1 (en) | 1990-12-21 | 1991-12-17 | Ink ribbon for thermal transfer printer |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5240781A (en) |
| EP (1) | EP0492356A1 (en) |
| JP (1) | JP3025311B2 (en) |
| CA (1) | CA2057780A1 (en) |
Families Citing this family (35)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4328348A1 (en) * | 1993-08-24 | 1995-03-02 | Du Pont Deutschland | A tonable radiation-sensitive mixture and process for making multicolor images by means of such a mixture |
| US5707082A (en) * | 1995-07-18 | 1998-01-13 | Moore Business Forms Inc | Thermally imaged colored baggage tags |
| JP3523724B2 (en) * | 1995-09-29 | 2004-04-26 | 東芝テック株式会社 | Thermal transfer color printer |
| US5683785A (en) * | 1995-11-01 | 1997-11-04 | Ncr Corporation | Thermal transfer medium for textile printing applications |
| US5747176A (en) * | 1995-11-20 | 1998-05-05 | Ncr Corporation | Ultra high scratch and smear resistant images for synthetic receivers |
| US5776280A (en) | 1995-12-18 | 1998-07-07 | Ncr Corporation | Receptive layer for thermal transfer printing on cartons |
| US5739189A (en) | 1995-12-18 | 1998-04-14 | Ncr Corporation | Low energy thermal transfer formulation |
| DE19780035D2 (en) * | 1996-01-26 | 1999-03-11 | Citius Gmbh Buerotechnik | Multilayer correction and / or marking material, process for its production and its use |
| US5952098A (en) | 1996-03-25 | 1999-09-14 | Ncr Corporation | Thermal transfer medium with phase isolated reactive components |
| EP0806302B1 (en) * | 1996-05-10 | 1999-10-13 | Ncr International Inc. | Thermal transfer medium |
| US6077594A (en) * | 1996-06-10 | 2000-06-20 | Ncr Corporation | Thermal transfer ribbon with self generating silicone resin backcoat |
| EP0812704B1 (en) * | 1996-06-10 | 2002-02-06 | Ncr International Inc. | Backcoat for thermal transfer ribbons |
| US5744226A (en) * | 1996-06-27 | 1998-04-28 | Ncr Corporation | Multilayerd thermal transfer medium for matte finish printing |
| US5843579A (en) * | 1996-06-27 | 1998-12-01 | Ncr Corporation | Magnetic thermal transfer ribbon with aqueous ferrofluids |
| US5824399A (en) * | 1996-06-27 | 1998-10-20 | Ncr Corporation | Multilayered thermal transfer medium with opaque sub-coat |
| US5866637A (en) * | 1996-07-23 | 1999-02-02 | Ncr Corporation | Magnetic thermal transfer ribbon with non-metallic magnets |
| US5866643A (en) * | 1996-09-23 | 1999-02-02 | Ncr Corporation | High print quality thermal transfer ribbons |
| US6057028A (en) * | 1996-09-24 | 2000-05-02 | Ncr Corporation | Multilayered thermal transfer medium for high speed printing |
| US5883043A (en) * | 1997-08-27 | 1999-03-16 | Ncr Corporation | Thermal paper with security features |
| US6770687B1 (en) | 1996-11-21 | 2004-08-03 | Ncr Corporation | Water-based dual security ink |
| US6031021A (en) * | 1997-04-11 | 2000-02-29 | Ncr Corporation | Thermal transfer ribbon with thermal dye color palette |
| US5932643A (en) * | 1997-04-11 | 1999-08-03 | Ncr Corporation | Thermal transfer ribbon with conductive polymers |
| US6025017A (en) * | 1997-05-21 | 2000-02-15 | Ncr Corporation | Photopolymerizable coating formulation for thermal transfer media |
| US6040040A (en) * | 1998-01-28 | 2000-03-21 | Ncr Corporation | Multi-layer thermal transfer media from selectively curable formulations |
| US6245416B1 (en) | 1998-05-20 | 2001-06-12 | Ncr Corporation | Water soluble silicone resin backcoat for thermal transfer ribbons |
| US6231964B1 (en) | 1998-06-30 | 2001-05-15 | Ncr Corporation | Thermal transfer ribbons with large size wax or resin particles |
| US6171690B1 (en) | 1998-08-28 | 2001-01-09 | Ncr Corporation | Thermal transfer media with a mixture of non-melting solid particles of distinct sizes |
| JP2000108532A (en) * | 1998-10-06 | 2000-04-18 | Fujicopian Co Ltd | Thermal transfer ribbon |
| US6166755A (en) * | 1998-10-27 | 2000-12-26 | Ncr Corporation | Thermal transfer ribbon with paper leader and trailer |
| US6517239B1 (en) | 1999-04-30 | 2003-02-11 | Ncr Corproation | Time-temperature indicators activated with thermal transfer printing and methods for their production |
| US6790493B2 (en) | 2001-12-21 | 2004-09-14 | Ncr Corporation | Epoxy curing agent emulsification for TTR application |
| US6989180B2 (en) * | 2003-10-09 | 2006-01-24 | Ncr Corporation | Thermal transfer ribbon with end of ribbon markers |
| US7645719B2 (en) * | 2004-10-13 | 2010-01-12 | Ncr Corporation | Thermal paper with security features |
| US7585444B2 (en) * | 2005-06-14 | 2009-09-08 | Illinois Tool Works Inc. | Method for reducing camber in coiled plastic ribbon or tape |
| WO2012036240A1 (en) | 2010-09-16 | 2012-03-22 | ブラザー工業株式会社 | Tape cassette and tape printing device |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60178088A (en) * | 1984-02-24 | 1985-09-12 | General Kk | Delay feeding heat-transfer printing medium |
| US4732815A (en) * | 1984-08-20 | 1988-03-22 | Dai Nippon Insatsu Kabushiki Kaisha | Heat transfer sheet |
| WO1986004859A1 (en) * | 1985-02-15 | 1986-08-28 | Fuji Kagakushi Kogyo Co., Ltd. | Hot melt copy recording medium |
| JPH0717109B2 (en) * | 1985-04-09 | 1995-03-01 | 株式会社東芝 | Thermal transfer ink ribbon and thermal transfer recording apparatus using the same |
| JPS61263797A (en) * | 1985-05-20 | 1986-11-21 | Ricoh Co Ltd | Thermal transfer recording medium |
| JPS6294382A (en) * | 1985-10-21 | 1987-04-30 | Ricoh Co Ltd | Thermal transfer recording medium |
| US4865901A (en) * | 1985-11-06 | 1989-09-12 | Brother Kogyo Kabushiki Kaisha | Thermal transfer printing ribbon |
| JPS62152790A (en) * | 1985-12-27 | 1987-07-07 | Canon Inc | Thermal transfer material and thermal transfer recording method |
| JP2590338B2 (en) * | 1987-07-02 | 1997-03-12 | 株式会社パイロット | Thermal transfer media |
| EP0367149B1 (en) * | 1988-10-28 | 1994-07-13 | Dai Nippon Insatsu Kabushiki Kaisha | Thermo-transfer sheet and label and manufacturing method of the same |
-
1990
- 1990-12-21 JP JP2405177A patent/JP3025311B2/en not_active Expired - Fee Related
-
1991
- 1991-12-17 CA CA002057780A patent/CA2057780A1/en not_active Abandoned
- 1991-12-17 EP EP91121569A patent/EP0492356A1/en not_active Ceased
- 1991-12-19 US US07/810,077 patent/US5240781A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP0492356A1 (en) | 1992-07-01 |
| JPH04220380A (en) | 1992-08-11 |
| US5240781A (en) | 1993-08-31 |
| JP3025311B2 (en) | 2000-03-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 19991217 |