CA1106560A - Method of manufacturing a plastics record carrier having a stratified structure as well as a device for carrying out the method - Google Patents
Method of manufacturing a plastics record carrier having a stratified structure as well as a device for carrying out the methodInfo
- Publication number
- CA1106560A CA1106560A CA298,551A CA298551A CA1106560A CA 1106560 A CA1106560 A CA 1106560A CA 298551 A CA298551 A CA 298551A CA 1106560 A CA1106560 A CA 1106560A
- Authority
- CA
- Canada
- Prior art keywords
- substrate
- mould
- resin
- moulding resin
- collar
- 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.)
- Expired
Links
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/02—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles
- B29C43/021—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles characterised by the shape of the surface
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
- B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
- B29C35/0888—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using transparant moulds
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B3/00—Recording by mechanical cutting, deforming or pressing, e.g. of grooves or pits; Reproducing by mechanical sensing; Record carriers therefor
- G11B3/68—Record carriers
- G11B3/70—Record carriers characterised by the selection of material or structure; Processes or apparatus specially adapted for manufacturing record carriers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
- B29C35/08—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation
- B29C35/0805—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation
- B29C2035/0827—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould by wave energy or particle radiation using electromagnetic radiation using UV radiation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/02—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles
- B29C43/021—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles characterised by the shape of the surface
- B29C2043/023—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles characterised by the shape of the surface having a plurality of grooves
- B29C2043/025—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles characterised by the shape of the surface having a plurality of grooves forming a microstructure, i.e. fine patterning
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2833/00—Use of polymers of unsaturated acids or derivatives thereof as mould material
- B29K2833/04—Polymers of esters
- B29K2833/12—Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2017/00—Carriers for sound or information
- B29L2017/001—Carriers of records containing fine grooves or impressions, e.g. disc records for needle playback, cylinder records
- B29L2017/003—Records or discs
-
- 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
- Y10S425/00—Plastic article or earthenware shaping or treating: apparatus
- Y10S425/81—Sound record
Abstract
ABSTRACT:
The invention relates to a method of manufac-turing a plastics record carrier, in particular a video disc, in which a mould is provided with a fluid moulding resin across which a substrate is provided. After curing the resin the assembly of substrate and cured layer of moulding resin bonded thereto is removed from the mould. According to the invention the substrate is spherosymmetrically vaulted and as such pressed against the quantity of moulding resin present centrally on the mould. The moulding resin is rolled over the surface of the mould with a circular fluid front with simultaneous deformation of the vaulted substrate. After the moulding resin has been spread over the whole mould and the plane surface, the moulding resin is cured. Thevaulting of the substrateis preferably realized by flexibly suspending a plane substrate at the edge and then adjusting a different gas pressure on both sides of the substrate. The moulding resin is preferably a radiation-curable moulding resin which is cured by exposure to, for example, ultra-violet light via the substrate. The invention also relates to a device for carrying out the above method which comprises inter alia a holder for the substrate which has a cylindrical flexible collar the end face of which comprises means to connect the substrate to the collar in a detachable and air-tight manner.
The invention relates to a method of manufac-turing a plastics record carrier, in particular a video disc, in which a mould is provided with a fluid moulding resin across which a substrate is provided. After curing the resin the assembly of substrate and cured layer of moulding resin bonded thereto is removed from the mould. According to the invention the substrate is spherosymmetrically vaulted and as such pressed against the quantity of moulding resin present centrally on the mould. The moulding resin is rolled over the surface of the mould with a circular fluid front with simultaneous deformation of the vaulted substrate. After the moulding resin has been spread over the whole mould and the plane surface, the moulding resin is cured. Thevaulting of the substrateis preferably realized by flexibly suspending a plane substrate at the edge and then adjusting a different gas pressure on both sides of the substrate. The moulding resin is preferably a radiation-curable moulding resin which is cured by exposure to, for example, ultra-violet light via the substrate. The invention also relates to a device for carrying out the above method which comprises inter alia a holder for the substrate which has a cylindrical flexible collar the end face of which comprises means to connect the substrate to the collar in a detachable and air-tight manner.
Description
The invention relates to a method of manufac-turing a plastics record carrier having a stratified struct-ure in which a fluid moulding resin is provided on a mould surface ha~ing an information track, a flexible substrate is provided on the layer of moulding resin, the layer of resin is cured and the assembly of substrate and attached :Layer of cured resin is removed from the mould.
~ uch a method is described in Netherlands Patent Application 7,411,707 by MCA Disco-Vision Inc. and laid open to public inspection on April 17, 1975 and is des-cribed in detail therein with reerence to Figure 5B. Accord-ing to this known method the whole surface of the mould is provided with the liquid moulding resin and suhsequently the substrate is provided over the layer of moulding resin by means of a cylindrical roller. Of course, the thickness of the layer of moulding resin is influenced and adjusted by the pressure with which the cylindrically curved substrate is pressed on the moulding resin. The method is less suitable for use in a larger scale production process. In addition the method has the principal drawback that, by using a cylindrical pressure roller, the layer of resin deformed in this manner, shows differences in thickness in directions at right angles to and parallel to the cylinder axis of the pressure roller.
The information track present in the mould and adopted by the resin is as a rule in the form of a spiral or otherwise consists of concentric circles. Said information track is scanned rotationally symmetrically in which speeds of rotation of the record carrier in the order of 1500 rpm are .~
~
realiæed. This relates to record carriers containing very refined video information, the so callecl video discs.
~ pplicants have gained t:he insight that the above described application of the layer of resin by means of a cylindrical roller has for its result that the finished prod-uct at scanning shows two inevitable errors with every revolution.
At the above mentioned rotation speed this leads to 3000 dis-turbances perminute, whichmeans an interference signal of50 Hz.
On the basis hereof Applicants have gained the further insight, on which thepresent invention is also based, that the layer of resin with its information trac~ has to be built up in the same manner as it is scanned and read afterwards in the reproduction apparatus, that is a rotationally symmetri-cal build~up.
The invention now relates to a method of the kind mentioned in the preamble and is characterized in that the flexible substrate which has been or is being vaulted spherosymmetrically, is pressed against -the moulding resin which is provided centrally on the mould, the moulding resin thereby being rolled out over the mould surface with a cir-cular fluid front and the vaulted substrate thereby being deformed to finally form a plane surface, the moulding resin being cured and the assembly of substrate with attached layer of cured resin being removed from the mould.
In a favourable embodiment of this method, when the circular fluid front of the moulding resin has nearly reached the edge of the mould, the substrate which has not yet been deformed entirely to form a plane surface, is uncoupled from the pressure force so that the substrate is relieved, thereby pushes the fluid front towards the edge of the mouldand engages the layer of resin without stress.
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. .. ..
It will be obvious that a substrate which engages the layer of resin ~ithout stress will provide, after curing o~ the layer of resin, a record carrier having no or only small internal stresses as a result: of which the possib-ility o~ deformation and possibly modulation of the storedinformation associated therewith is minimized.
The resulting plastics record carrier, after separation from the mould, also has the smoothness of the mould. Starting from a substrate which is not entirely plane, an entirely plane plastics record carrier can be obtained, provided the mould be plane.
In a further favourable embodiment of the method according to the invention~ the spherosymmetrically vaulted substrate is pressed against the moulding resin which has been deposited centrally on the mould in the form of a ring.
According to -this preferred embodiment of the method, record carriers, for example video discs, can be manufactured in ;~ which no layer of resin is present in the central poxtion.
Said portion may be used, for example, for providing a label.
In a further elaboration of the last-mentioned preferred embodiment, a spherosymmetrical substrate is used which has central aperture, the diameter of the aperture correspond-ing to or being smaller than the insidediameter of the annular layer of resin deposited on the mould. The aperture present in the resulting record carrier may serve to centre the record carrier around a centring pin present in the reproduction apparatus.
A spherosymmetrically vaulted substrate is used in the method according to the invention. It is recom-mendable to realize the spherosymmetrical design oE the sub-strate by flexibly suspending or supporting a plane sub-strate, which is in the form of a circle or ring, along , . .
~ - 4 ~6~ P~IN 8712 its whole circumference and then providlng a gas pressure which is different on both sides of the subs-trate.
Accordin~ to a further ~avourable embodiment of the method according to the invention the difference in gas pressure is variable and also forms the force with which the spherosym-metrically vaulted substra-te is pressed against the moulding resln .
In the method according to the invention the con-ventionally used polymerisable moulding resins, for example the thermosetting urethane resin provided with a catalyst as stated in the above-mentioned Netherlands Patent Application 7,411,707, may be used. A radiation-curable moulding resin i5 pre~erably used which is exposed vla the substrate after having been rolled out completely over the mould.
Very suitable, radiation-curable moulding resins are those which are described in our Canadian Patent Application No. 288,224 which was filed on Oct. 5/77. Such readily usable moulding resins comprise low-molecular monomers and/or oligomers which cont~in on an average 25-70~ by weight of saturated hydro-carbon groups and/or phenyl ~roups, are furthermore aprotic and have an average functionality as regards unsaturation which lies between the values 2 and 6.
Thin-liquid mixtures of low-molecular mono-, di-, tri~ or tetra ester of acrylic acid are preferably used to which a photosensitive catalyst, for example an aromatic carbonyl com-pound, for example benzoin-isobutyl ether, has been added~
~xamples of acrylic acid esters are 2-ethylhexyl-acrylate, ethylacrylate, phenylacrylate, 2-ethoxyethylacrylate and octadecylacrylate.
The mould used in the method according to the inven-tion i5 preferably a mould of which at least the surface com-A - ',, . ,~ .
~ PHN 8712 prising the information track is manufactllred from metal.
A very suitable mould is a mould manufactured from nickel as described, for example, in our Canadian Patent 99~,173 which issued on Oct. 5, 1976. The mould preferably has on its side remote from the information track a plane stiffening plate, for example, an aluminium plate having a thickness of 1 to 10 mm.
The above-described, radiation-curable moulding resin does not adhere to the metal mould after curing but can readily be detached from the mould. A separate detaching agent is not necessary and is not desired either because the transfer of information from the mould to the moulding resin should be as accurate as possible.
As a substrate a plastics plate is used having a thickness between 100/um and 1.5 mm. When radiation-curable ;~ moulding resins are used, the substrate should be pervious to .
- the radiation used, for example ultra-violet light~ Suitable plastics are, for example, polyvinylchloride, copolymeric vinylchloride vinyl acetate, polycarbonate polyester, poly-methylmethacrylake and polystyrene. The above mentioned mould-i~g resins read:ily adhere to the said substrates. If desired the adhesion may be improved by chemically roughening the sub-strate with, for example, chloroform or providing it with an adhesion-improving top layer. For example, plexiglass may be provided with a top layer of polyvinylchloride/acetate.
The invention also relates to a device for carry-ing out the method according to the invention which comprises a holder for the flexible substrate, which holder has a con-: nection possibility for a pump, a support plate for the mould, as well as a source of power to move the holder or part of theholder relative to the support plate.
:
Such a device is known in itself from German Patent Specification 1,094,996, wherein a press Eor gramophone records is disclosed in which at least one of the two press moulds is provided with a flexible diaphragm, the edge portion of which is clamped between the press mould and a pressuxe ring connected to the mould~s) by a screw joint. The press mould has a pressure line through which liquid is pressed bet~
ween the press mould and the diaphragm and consequently the diaphragm is deformed to become conve~. This known device is not suitable for carrying out the method according to the invention and has inter alia the drawback that the diaphragm cannot easily be removed from the press mould. In this case it is to be noted that in the method according to the present invention the flexible substrate has to be removed from the mould together with the cured la~er of moulding resin. The substrate forms part of the record carrier so that a separate flexible substrate is needed for each plastics record carrier to be produced. In the device known from German Patent Speci- -fication 1,094,996 the diaphragm which does not form part of the record disc to be produced is permanently connected to the press mould and serves to expel the air present between the press mould and the disc to be pressed.
~ he invention provides a device of the above~
mentioned kind which is particularly suitable for carrying out the method according to the invention and is characterized in that the holder comprises an elastically deformable cylindric-al collar which at its annular end face remote from the holder comprises means to connect the substrate to the said collar along the circumference in a detachable and air-tight manner.
3Q In the preferred embodiment of the device according to the invention the end face of the collar comprises ~r ` --7--.
,, ~6~ PHN ~712 one or more vacuum grooves in which a sub-atmospheric pressure can be generated so that the substrate is sucked against the collar.
In this preferred embodiment of the device the substrate can be uncoupled from the holder in a very simple manner, namely by removing the sub-atmospheric pressure in the vacuum grooves.
In a ~urther favourable embodiment of the device the cylindrical collar is closed by a flexible diaphragm on the side of the end ace.
Said flexible diaphragm const.itutes an extra sup-port over the entire surface of a substrate sucked on the end : face on the collar. This is of particular importance if a sub-strate having a central aperture is used in the device accord-ing to the invention. In a particularly suitable embodiment of the device according to the invention which is meant espec~
ially for handling substrates having a central aperture, the abo~e-mentioned diaphragm comprises a central recessed portion and furthermore the mould comprises a central boss, the boss fi.tting in the recessed portion of the diaphragm.
According to another favourable embodiment of the device according to -the invention the support plate with mould : is situated entirely within the holder of the substrate. By placing the substrate in the holder an entirely closed system is obtained in which notably the moulding resin provided on the mould is completely protected from ambient influences.
~: More par-ticularly, in this favourable embodiment : the collar at its end remote from the substrate comprises a projecting elastically deformable annular flange which at its free end is connected to a cylindrical jacket which at its end : remote from the flange is closed by a bottom portion~ the sup-:
.. , 8 ~, ~6~ PHN 8712 port pla-te with mould extends from the bottom portion into the space bounded by jacket, flange and col:Lar, the mould being parallel to the substrate and the device comprising a connec~
tion possikility for connecting a vacuum pump, in which, by providing sub-atmospheric pressure in the said space, the sub-strate is deformed so as to be spherosyrnmetrical and pressed against the mould under elastic deformation of collar and flange.
The invention will be described in greater detail with reference to the drawing, in which Figwres 1-3 are cross-sectional views of a device or a part of the device according to the invention in several stages of the method according to the invention carried out with the device.
Figures 4 and 8, Fig. 8 being on the same sheet as Fig. 4, are cross-sectional views of a plastics record car-rier manufactured by means of the method according to the invention~
Figures 5-7, Fig. 7 being on the same sheet as Fig. 4, are cross-sectional views of an another embodiment of the device according to the invention in various stages o~ the method according to the invention carried out with the device, Figures 9-11 are cross-sectional views of still another embodiment of the device according to the invention -also in various stages of the method carried out by means of the device.
Reference numeral 1 in Figure 1 denotes a support plage for a nickel mould 2 of which the surface remote from the support plate 1 comprises a spiral-like information track.
Provided centrally on the mould 2 is a quantity 3 of a UV-curable moulding resin on the basis of an acrylin acid ester.
_ 9 _ .
The support plate 1 is placed on table 5 by means of adjusting pins ~. The position of the support plate 1 relative to the table 5 can be adjusted by means of the adjusting pins. Table 5 comprises a column 6 which has an arm 7. A linear motor 8 is securad to arm 7 and has a shaft 9 which can be moved in the directions shown by means of the motor 3. Shaft 9 com-prises on its side remote from the motor a holder 10 for a flexible substrate 11. Holder 10 comprises a cylindrical col-lar 12 manufactured from deformable material, for example rubber, which, at its end face remote from the holder 10, has an annular suction cup 13. Collar 12 has a perforation 14 which at one end extends lnto the suction cup 13 and at the other end passes through the holder 10 connected ko the collar 12. Vla the peroration a sub-atmospheric pressure can be provided in the suction cup 13 by means of a vacuum pump, not shown, as a result of which the flexible circular substrate plate 11 which is manufactured from a material which passes U~
light, for example plexiglass, is sucked against the collar 12 vla the suction cup 13. Holder 10 has a second perforation 15 extending into the space 16 which is bounded by holder 10, col-lar 12 and substrate 11 and which otherwise is air-tight. An elevated pressure is realized in space 16 vla perforation 15 which can be made to communicate with a pressure pump, not shown.
~ 25 The method accordi.ng to the invention performed :~ by means of the device runs off as follows~
As a result of an over pressure provicled in space 16, the flexible substrate 11 will be vaulted or deformed spherosym~letrically with simultaneous elastic deformation of collar 12 with sucker 13.
The assembly of holder 10 with collar 12, sucker ,,~, , - 1 0 6~
PH~ 8712 13, and spherosymmetrically vaulted substrate 11 sucked thereon is moved by the motor 8 in the direction of the support plate 1 with mould 2 and moulding resin 3 presen-t below the substrate 11. The central portion of the spherosymme-trically vaulted substrate 11 will contact the moulding resin 3 first. When the holder 10 with substrate 11 is further lowered, the mould-ing resin will be rolled by the vaulted substrate over the mould 2, the moulding resin spreading over the mould with a circular fluid front and the spherosymmetrically vaul-ted sub-strate being simultaneously deformed, that is flattened.
Figure 2 shows the situation in which the mould-ing resin is spread partly over the surface of the mould. The reference numerals used in Figure 2 correspond to those of Figure 1.
It is to be noted that upon rolling the moulding resin the hydraulic resistance of the layer of moulding resin which is inversely proportional to the third power of the thickness o~ the layer of moulding resin correspond to the elastic resistance force of the deformed substrate.
~0 When the substrate 11 has been deformed substant-ially entirely to form a plane surface and the fluid front has nearly reached the edge of the mould, the substrate 11 is uncoupled from collar 12 with suc]cer 13 in that air is admitted to the sucker 13 vla perforation 14 so that the applied sub-atmospheric pressure is removed. Upon uncoupling, the sub-strate 11, as a result of its natural stress relief, will engage entirely flatly against the surface of the mould and stow the fluid front of the resin 3 up to the edge of the mould.
Via the substrate 11 which engages the moulding resin 3 with-out stress, the layer of moulding resin is cured by exposure toultraviolet light originating from light source 17 ~Figure 3), . . :
i6~
for example ultra-violet light of 350 nm originating from a 500 watt water-cooled high pressure mercury lamp. The expos-ure time depends, for example, on the -~hickness of the layer of moulding resin which may vary from 0.2 to 300/um but is S preferably 1-75/um, on the composition of the moulding resin, on the light intensity and on the thickness of the substrate which as a rule is from 1-3 mm. Generally the exposure time will vary from a few seconds to a few minutes.
After curing, in which the substrate 11 is bonded to the moulding resin 3, the resulting plastics record carrier is removed from the mould. Figure 4 shows the plastics record carrier which consists of the cured layer of moulding resin 18 having an information pattern and the substrate plate 11 bonded thereto.
Usually, the plastics record carrier is provided on the side of the layer of moulding resin comprising the information with a 300 ~ thick Al layer (not shown in Figure 4) which is vapour-deposited in a vacuum hell at a pressure of 10 4 to 10 5 Torr. Finally, a protective lacquer layer (not shown in Figure 4) is provided on the Al layer by pouring nitrocellulose lacquer on the Al layer and centrifuging the assembly, the nitrocellulose lacquer spreading as a thin layer over the Al layer.
Reference numeral 19 in Figure 5 denotes a sup-port plate for a nickel mould 20 which has a central pin 21.
: An annular quantity 22 of a UV-curable moulding resin is pro-vided on the metal mould 20 around the pin 21. Support plate 19 is secured to table 24 in an adjustable manner by means of adjusting pins 23, the table comprising a column 25 with sup-port arm 26. A linear motor 27 having a movable shaft 28 is secured to support arm 26. At its end remote from the motor ~-a~
27 the movable shaft 28 is connected -to a holder 29 for the flexible substrate 30. Holder 29 has a flexible cylindrical collar 31 which, at its end remote from the holder, has a widening 32 in which a vacuum duct 33 is provided. At its end remote from the holder 29, collar 31 is closed by a flexible diaphragm 34 which is mainly circular and has a central rec-essed portion 35. ~n this manner, an a:ir-tight space 39 is formed between holder 29, holder 31 and diaphragm 34, in which space an excessive gas pressure can be provided by suitable means, for example a pressure pump, which are not shown in the Figure, vla a perforation 36. ~Iolder 29 comprises a second perforation 37 extending through collar 31 into vacuum duct 33. By communicating holder 29 with a vacuum pump not shown, a sub-atmospheric pressur~ can be produced in duct 33 vla per-foration 37. As a result of said sub-atmospheric pressure the edge of the flexible substrate 30 is sucked against the widened portion 32 of collar 31. The flexible substrate 30 which has a central aperture 38 the dimension of which corresponds to ~` the inside dimension of the central recessed portion 35 of dia-phragm 34, will engage the non-recessed portion of diaphragm 34. The substrate 30 is manufactured from UV passing plastics, .
~or example polymethylmethacrylate (Plexiglass).
The operation of the device is as follows.
: As a result of an over pressure applied in space 25 39, the diaphragm 34 and the substrate 30 engaging it will be deformed spherosymmetrically. The assembly of holder 29, col-lar 34 and the spherosymmetrically vaulted diaphragm 34 with :~
substrate 30 is moved in the direction of the mould 20 with moulding resin 22 by means of motor 8. The part of the sub-strate 30 adjoining the circular aperture will first contact the annular quantity of moulding resin 22 which is situated .... - 13 .~.,.
~ ~ PHN 8712 around pin 21 on the mould 20. Substrate 30 with aperture 38 will centre around pin 21. The diameter of pin 21 corresponds to the diameter of aperture 38 and also to the inside diameter of recessed portion 35 o~ diaphragm 34. When the holder 2S
with diaphragm 34 and substrate 30 is further lowered, the moulding resin 22 will be rolled over mould 20 by means of the vaulted substrate 30 and spread over the surface of mould 20 with a circular fluid front. Deformation, that is flattening of the spherosymmetrically vaulted diaphragm 34 and substrate 30, will take place while furthermore pin 21 extends via aper-ture 3~ of substrate 30 in recessed portion 35 of diaphraym 34.
Figure 6 shows the situation in which the mould-ing resin 22 is partly spread over the surface o~ the mould.
The reference numerals used in Figure 6 correspond to those of Figure 5.
; When the fluid front of moulding resin 22 has nearly reached the edge of mould 20 and the diaphragm 34 with substrate 30 has nearly been deformed to a plane surface, air is admitted via performation 37 so that the sub-atmospheric pressure in the duct 33 is removed. As a result of this the substrate 30 will be uncoup:Led from holder 29 and the sub-strate, as a result of natural stress relief, will be stre~
` tched entirely and engage mould 20 in a plane sur~ace. The resin 22 is rolled entirely onto the edge of the mould 20.
The moulding resin 22 is cured with U~-light from ligh-t sources 40 via substrate 30 (Figure 7). The expos-ure is carried out in the same manner as described with refer-ence to Figure 3. It is to be noted that the support plate, the mould and the substrate preferably have the same outside diameters so that the excess of moulding resin after curing can easily be cut away without damaging the layer of resin ~6~ PHN 8712 between mould and substrate.
After curing, the resulting assembly of sub-strate 30 and the cured layer of mouldiny resin 42 haviny an information -track 41 (Figure 8) is removed frum the mould.
This removal may be carried out, for example, by placing the widened end 32 of collar 31 against the assembly, then pro-viding a sub-atmospheric pressure in vacuum duc-t 33 so that the assembly is sucked against collar 31, and then raising the holder 29 by means of the linear motor 27 80 that the assembly connected to holder 29 via collar 31 is pulled from mould 20.
Figure 8 shows the resulting plastics inform-ation carrier in which substrate 30 is bonded to the cured : layer of moulding resin 42 which has an information pattern 41. The plastics record carrier has a central aperture 43O
Reference numeral 44 in Figure 9 denotes a holder for sub-strate 45. The holder comprises a circular bo-ttom portion 46 which is connected at its edge to an upright cylindrical jacket 47. At its end remote from bottom portion 46 to jacket 47 has an inwardly directed flange 48 which in turn comprises at its free end an upright collar 49. At its end face the collar 49 has an annular vacuum duct 50 in which a ; sub-atmospheric pressure can be provided via perforation 51 and by means of the vacuum pump not shown. The perforation extends from the vacuum duct 50 axially through collar 49, then radially through flange 48 and jacket 47 ana opens into the outer surface of jacket 47.
Substrate 45 is sucked against the end face of collar 49 by using a sub-atmospheric pressure in duct 50.
An air-tight space 52 is enclosed by substrate 45, collar 49, .c'712 i 5 - Ll - 1 9 7 7 flan~e ~, jac,ke-t /1 7 cUlCI bo~-torn ~l6. ~ SllppOl't p1ate 53 o*
moul(l 5l~ is accolnnlodat,et,l -in spclce 5.~. Tlle sl-lp-p~rt pl;lt~
53 ha~ a f'lclnLr~;e por-tion ~5 wh-ich beLlrs on bottonl por-tlon l~6.
The diamet-*lr of`-rlange por-t:ion 55 cor-responds to the inside d:iarrlel;er of jacke-t 4 7 . rrhe mould 5LI which :is pro~idecl on the suppo,r-t p:late S3 ancl which :is parallel -to subs-tra-te 45, is providecl ceI)trally wi-th moulding resin 56. A sub-a-tmos-pher-ic pressure can be provided in the said air-tight space 52 via-perforation 57 by means of a vacuum pump, no-t shown.
The method accordingr to the in~rention carriecl out by means of this de~ice runs off as follows.
A sub-atmospheric pressure is provided ln space 52 v:La perforation 57. ~s a result of this, the substrate 45 whlch ls sucked against collar ~l9 wil] be deformed sphero syrnme-trically w:Lth simultan~ous elastic defortnation of collar 49. Dur:ing said deforlnation -the central portion of substrate 45 will contact the moulding resin 56 prcsent central1y on mould 54 and the subs-tra-te 45, when the sub-atmospheric pressure is increased, will then roll the moul-ding resin over the surface of mould 5~1 with a circular fluid front. Figure 10 shows the situa-tion ln which the sub-strate 45 has sprcad the mould:ing resin 55 over a part of mould 5 L~, The reference numer2ls :in Figure 10 correspond to those of Figure 9.
In the further continuous increase of the sub~
atmospheric pressure in space 52, elastic deformation of the flange Ll8 tal~es place so that the assem~ly of substra-te 45 with collar 49 and flange 4c~ is moved in the direction of mould 54. As a resul-t of' the increasecl pressure o~ the substrate 45 OIl the mould wi-th mouldillg resin 56, the moul--din~g resin will be further spreacl over the mouldO It will be ll-IN.S71~
15 ~ ) 7 '7 obv:i.ous i;h~t durirlg r :II.i.ng thc re.9:ill 56, the vaullecl sub--~strate 1I5 wi.]] colIt:i.nuousl.y be :f:L.IttenecI :froIn the cent:re.
~i`i.glI:re 11 sl~o~ci tllc s~ c1.t;:i.0:rl lrl which no Iu.:r--ther moveIlIent o~ substrate /I5~ collar 39 ~lnd Lla:rlge I~S -takes ~ ce a.ny lorIger. .The substrate ~5 has been.:tully ~la-tte~llecI
and bears agains-t the mou:LcI:ing resi.n 56 wlIich :is spreacl over the who:Le mou:Ld surrace .Cn -th:is situa-t:ion tI~le layer of oulding resin 56 is exposed to ultra~violet li.ght from light sources 58 and is cured. By graclually removing the sub-atmosph.eric pressure in space 52 ~lange l~c3 and coll.ar /~9 will gradua]ly return elast:ically -to -the original pos:ition in which the substrate 45 with the cured layer o~ moulding resin 56 bonded thereto is released :from the mould sur~ace.
~inally -the sub-atmosE)he:r:i.c pressIlre :i.:n duct 50 is removed 15 an.d the result:ing plact:ics record carrier can be removed from the holder 51~ ~s already s-tated above the resultil1.g record carrier ma~ be provided with a reflecting layer and a protective lacquer.
~ uch a method is described in Netherlands Patent Application 7,411,707 by MCA Disco-Vision Inc. and laid open to public inspection on April 17, 1975 and is des-cribed in detail therein with reerence to Figure 5B. Accord-ing to this known method the whole surface of the mould is provided with the liquid moulding resin and suhsequently the substrate is provided over the layer of moulding resin by means of a cylindrical roller. Of course, the thickness of the layer of moulding resin is influenced and adjusted by the pressure with which the cylindrically curved substrate is pressed on the moulding resin. The method is less suitable for use in a larger scale production process. In addition the method has the principal drawback that, by using a cylindrical pressure roller, the layer of resin deformed in this manner, shows differences in thickness in directions at right angles to and parallel to the cylinder axis of the pressure roller.
The information track present in the mould and adopted by the resin is as a rule in the form of a spiral or otherwise consists of concentric circles. Said information track is scanned rotationally symmetrically in which speeds of rotation of the record carrier in the order of 1500 rpm are .~
~
realiæed. This relates to record carriers containing very refined video information, the so callecl video discs.
~ pplicants have gained t:he insight that the above described application of the layer of resin by means of a cylindrical roller has for its result that the finished prod-uct at scanning shows two inevitable errors with every revolution.
At the above mentioned rotation speed this leads to 3000 dis-turbances perminute, whichmeans an interference signal of50 Hz.
On the basis hereof Applicants have gained the further insight, on which thepresent invention is also based, that the layer of resin with its information trac~ has to be built up in the same manner as it is scanned and read afterwards in the reproduction apparatus, that is a rotationally symmetri-cal build~up.
The invention now relates to a method of the kind mentioned in the preamble and is characterized in that the flexible substrate which has been or is being vaulted spherosymmetrically, is pressed against -the moulding resin which is provided centrally on the mould, the moulding resin thereby being rolled out over the mould surface with a cir-cular fluid front and the vaulted substrate thereby being deformed to finally form a plane surface, the moulding resin being cured and the assembly of substrate with attached layer of cured resin being removed from the mould.
In a favourable embodiment of this method, when the circular fluid front of the moulding resin has nearly reached the edge of the mould, the substrate which has not yet been deformed entirely to form a plane surface, is uncoupled from the pressure force so that the substrate is relieved, thereby pushes the fluid front towards the edge of the mouldand engages the layer of resin without stress.
.
. .. ..
It will be obvious that a substrate which engages the layer of resin ~ithout stress will provide, after curing o~ the layer of resin, a record carrier having no or only small internal stresses as a result: of which the possib-ility o~ deformation and possibly modulation of the storedinformation associated therewith is minimized.
The resulting plastics record carrier, after separation from the mould, also has the smoothness of the mould. Starting from a substrate which is not entirely plane, an entirely plane plastics record carrier can be obtained, provided the mould be plane.
In a further favourable embodiment of the method according to the invention~ the spherosymmetrically vaulted substrate is pressed against the moulding resin which has been deposited centrally on the mould in the form of a ring.
According to -this preferred embodiment of the method, record carriers, for example video discs, can be manufactured in ;~ which no layer of resin is present in the central poxtion.
Said portion may be used, for example, for providing a label.
In a further elaboration of the last-mentioned preferred embodiment, a spherosymmetrical substrate is used which has central aperture, the diameter of the aperture correspond-ing to or being smaller than the insidediameter of the annular layer of resin deposited on the mould. The aperture present in the resulting record carrier may serve to centre the record carrier around a centring pin present in the reproduction apparatus.
A spherosymmetrically vaulted substrate is used in the method according to the invention. It is recom-mendable to realize the spherosymmetrical design oE the sub-strate by flexibly suspending or supporting a plane sub-strate, which is in the form of a circle or ring, along , . .
~ - 4 ~6~ P~IN 8712 its whole circumference and then providlng a gas pressure which is different on both sides of the subs-trate.
Accordin~ to a further ~avourable embodiment of the method according to the invention the difference in gas pressure is variable and also forms the force with which the spherosym-metrically vaulted substra-te is pressed against the moulding resln .
In the method according to the invention the con-ventionally used polymerisable moulding resins, for example the thermosetting urethane resin provided with a catalyst as stated in the above-mentioned Netherlands Patent Application 7,411,707, may be used. A radiation-curable moulding resin i5 pre~erably used which is exposed vla the substrate after having been rolled out completely over the mould.
Very suitable, radiation-curable moulding resins are those which are described in our Canadian Patent Application No. 288,224 which was filed on Oct. 5/77. Such readily usable moulding resins comprise low-molecular monomers and/or oligomers which cont~in on an average 25-70~ by weight of saturated hydro-carbon groups and/or phenyl ~roups, are furthermore aprotic and have an average functionality as regards unsaturation which lies between the values 2 and 6.
Thin-liquid mixtures of low-molecular mono-, di-, tri~ or tetra ester of acrylic acid are preferably used to which a photosensitive catalyst, for example an aromatic carbonyl com-pound, for example benzoin-isobutyl ether, has been added~
~xamples of acrylic acid esters are 2-ethylhexyl-acrylate, ethylacrylate, phenylacrylate, 2-ethoxyethylacrylate and octadecylacrylate.
The mould used in the method according to the inven-tion i5 preferably a mould of which at least the surface com-A - ',, . ,~ .
~ PHN 8712 prising the information track is manufactllred from metal.
A very suitable mould is a mould manufactured from nickel as described, for example, in our Canadian Patent 99~,173 which issued on Oct. 5, 1976. The mould preferably has on its side remote from the information track a plane stiffening plate, for example, an aluminium plate having a thickness of 1 to 10 mm.
The above-described, radiation-curable moulding resin does not adhere to the metal mould after curing but can readily be detached from the mould. A separate detaching agent is not necessary and is not desired either because the transfer of information from the mould to the moulding resin should be as accurate as possible.
As a substrate a plastics plate is used having a thickness between 100/um and 1.5 mm. When radiation-curable ;~ moulding resins are used, the substrate should be pervious to .
- the radiation used, for example ultra-violet light~ Suitable plastics are, for example, polyvinylchloride, copolymeric vinylchloride vinyl acetate, polycarbonate polyester, poly-methylmethacrylake and polystyrene. The above mentioned mould-i~g resins read:ily adhere to the said substrates. If desired the adhesion may be improved by chemically roughening the sub-strate with, for example, chloroform or providing it with an adhesion-improving top layer. For example, plexiglass may be provided with a top layer of polyvinylchloride/acetate.
The invention also relates to a device for carry-ing out the method according to the invention which comprises a holder for the flexible substrate, which holder has a con-: nection possibility for a pump, a support plate for the mould, as well as a source of power to move the holder or part of theholder relative to the support plate.
:
Such a device is known in itself from German Patent Specification 1,094,996, wherein a press Eor gramophone records is disclosed in which at least one of the two press moulds is provided with a flexible diaphragm, the edge portion of which is clamped between the press mould and a pressuxe ring connected to the mould~s) by a screw joint. The press mould has a pressure line through which liquid is pressed bet~
ween the press mould and the diaphragm and consequently the diaphragm is deformed to become conve~. This known device is not suitable for carrying out the method according to the invention and has inter alia the drawback that the diaphragm cannot easily be removed from the press mould. In this case it is to be noted that in the method according to the present invention the flexible substrate has to be removed from the mould together with the cured la~er of moulding resin. The substrate forms part of the record carrier so that a separate flexible substrate is needed for each plastics record carrier to be produced. In the device known from German Patent Speci- -fication 1,094,996 the diaphragm which does not form part of the record disc to be produced is permanently connected to the press mould and serves to expel the air present between the press mould and the disc to be pressed.
~ he invention provides a device of the above~
mentioned kind which is particularly suitable for carrying out the method according to the invention and is characterized in that the holder comprises an elastically deformable cylindric-al collar which at its annular end face remote from the holder comprises means to connect the substrate to the said collar along the circumference in a detachable and air-tight manner.
3Q In the preferred embodiment of the device according to the invention the end face of the collar comprises ~r ` --7--.
,, ~6~ PHN ~712 one or more vacuum grooves in which a sub-atmospheric pressure can be generated so that the substrate is sucked against the collar.
In this preferred embodiment of the device the substrate can be uncoupled from the holder in a very simple manner, namely by removing the sub-atmospheric pressure in the vacuum grooves.
In a ~urther favourable embodiment of the device the cylindrical collar is closed by a flexible diaphragm on the side of the end ace.
Said flexible diaphragm const.itutes an extra sup-port over the entire surface of a substrate sucked on the end : face on the collar. This is of particular importance if a sub-strate having a central aperture is used in the device accord-ing to the invention. In a particularly suitable embodiment of the device according to the invention which is meant espec~
ially for handling substrates having a central aperture, the abo~e-mentioned diaphragm comprises a central recessed portion and furthermore the mould comprises a central boss, the boss fi.tting in the recessed portion of the diaphragm.
According to another favourable embodiment of the device according to -the invention the support plate with mould : is situated entirely within the holder of the substrate. By placing the substrate in the holder an entirely closed system is obtained in which notably the moulding resin provided on the mould is completely protected from ambient influences.
~: More par-ticularly, in this favourable embodiment : the collar at its end remote from the substrate comprises a projecting elastically deformable annular flange which at its free end is connected to a cylindrical jacket which at its end : remote from the flange is closed by a bottom portion~ the sup-:
.. , 8 ~, ~6~ PHN 8712 port pla-te with mould extends from the bottom portion into the space bounded by jacket, flange and col:Lar, the mould being parallel to the substrate and the device comprising a connec~
tion possikility for connecting a vacuum pump, in which, by providing sub-atmospheric pressure in the said space, the sub-strate is deformed so as to be spherosyrnmetrical and pressed against the mould under elastic deformation of collar and flange.
The invention will be described in greater detail with reference to the drawing, in which Figwres 1-3 are cross-sectional views of a device or a part of the device according to the invention in several stages of the method according to the invention carried out with the device.
Figures 4 and 8, Fig. 8 being on the same sheet as Fig. 4, are cross-sectional views of a plastics record car-rier manufactured by means of the method according to the invention~
Figures 5-7, Fig. 7 being on the same sheet as Fig. 4, are cross-sectional views of an another embodiment of the device according to the invention in various stages o~ the method according to the invention carried out with the device, Figures 9-11 are cross-sectional views of still another embodiment of the device according to the invention -also in various stages of the method carried out by means of the device.
Reference numeral 1 in Figure 1 denotes a support plage for a nickel mould 2 of which the surface remote from the support plate 1 comprises a spiral-like information track.
Provided centrally on the mould 2 is a quantity 3 of a UV-curable moulding resin on the basis of an acrylin acid ester.
_ 9 _ .
The support plate 1 is placed on table 5 by means of adjusting pins ~. The position of the support plate 1 relative to the table 5 can be adjusted by means of the adjusting pins. Table 5 comprises a column 6 which has an arm 7. A linear motor 8 is securad to arm 7 and has a shaft 9 which can be moved in the directions shown by means of the motor 3. Shaft 9 com-prises on its side remote from the motor a holder 10 for a flexible substrate 11. Holder 10 comprises a cylindrical col-lar 12 manufactured from deformable material, for example rubber, which, at its end face remote from the holder 10, has an annular suction cup 13. Collar 12 has a perforation 14 which at one end extends lnto the suction cup 13 and at the other end passes through the holder 10 connected ko the collar 12. Vla the peroration a sub-atmospheric pressure can be provided in the suction cup 13 by means of a vacuum pump, not shown, as a result of which the flexible circular substrate plate 11 which is manufactured from a material which passes U~
light, for example plexiglass, is sucked against the collar 12 vla the suction cup 13. Holder 10 has a second perforation 15 extending into the space 16 which is bounded by holder 10, col-lar 12 and substrate 11 and which otherwise is air-tight. An elevated pressure is realized in space 16 vla perforation 15 which can be made to communicate with a pressure pump, not shown.
~ 25 The method accordi.ng to the invention performed :~ by means of the device runs off as follows~
As a result of an over pressure provicled in space 16, the flexible substrate 11 will be vaulted or deformed spherosym~letrically with simultaneous elastic deformation of collar 12 with sucker 13.
The assembly of holder 10 with collar 12, sucker ,,~, , - 1 0 6~
PH~ 8712 13, and spherosymmetrically vaulted substrate 11 sucked thereon is moved by the motor 8 in the direction of the support plate 1 with mould 2 and moulding resin 3 presen-t below the substrate 11. The central portion of the spherosymme-trically vaulted substrate 11 will contact the moulding resin 3 first. When the holder 10 with substrate 11 is further lowered, the mould-ing resin will be rolled by the vaulted substrate over the mould 2, the moulding resin spreading over the mould with a circular fluid front and the spherosymmetrically vaul-ted sub-strate being simultaneously deformed, that is flattened.
Figure 2 shows the situation in which the mould-ing resin is spread partly over the surface of the mould. The reference numerals used in Figure 2 correspond to those of Figure 1.
It is to be noted that upon rolling the moulding resin the hydraulic resistance of the layer of moulding resin which is inversely proportional to the third power of the thickness o~ the layer of moulding resin correspond to the elastic resistance force of the deformed substrate.
~0 When the substrate 11 has been deformed substant-ially entirely to form a plane surface and the fluid front has nearly reached the edge of the mould, the substrate 11 is uncoupled from collar 12 with suc]cer 13 in that air is admitted to the sucker 13 vla perforation 14 so that the applied sub-atmospheric pressure is removed. Upon uncoupling, the sub-strate 11, as a result of its natural stress relief, will engage entirely flatly against the surface of the mould and stow the fluid front of the resin 3 up to the edge of the mould.
Via the substrate 11 which engages the moulding resin 3 with-out stress, the layer of moulding resin is cured by exposure toultraviolet light originating from light source 17 ~Figure 3), . . :
i6~
for example ultra-violet light of 350 nm originating from a 500 watt water-cooled high pressure mercury lamp. The expos-ure time depends, for example, on the -~hickness of the layer of moulding resin which may vary from 0.2 to 300/um but is S preferably 1-75/um, on the composition of the moulding resin, on the light intensity and on the thickness of the substrate which as a rule is from 1-3 mm. Generally the exposure time will vary from a few seconds to a few minutes.
After curing, in which the substrate 11 is bonded to the moulding resin 3, the resulting plastics record carrier is removed from the mould. Figure 4 shows the plastics record carrier which consists of the cured layer of moulding resin 18 having an information pattern and the substrate plate 11 bonded thereto.
Usually, the plastics record carrier is provided on the side of the layer of moulding resin comprising the information with a 300 ~ thick Al layer (not shown in Figure 4) which is vapour-deposited in a vacuum hell at a pressure of 10 4 to 10 5 Torr. Finally, a protective lacquer layer (not shown in Figure 4) is provided on the Al layer by pouring nitrocellulose lacquer on the Al layer and centrifuging the assembly, the nitrocellulose lacquer spreading as a thin layer over the Al layer.
Reference numeral 19 in Figure 5 denotes a sup-port plate for a nickel mould 20 which has a central pin 21.
: An annular quantity 22 of a UV-curable moulding resin is pro-vided on the metal mould 20 around the pin 21. Support plate 19 is secured to table 24 in an adjustable manner by means of adjusting pins 23, the table comprising a column 25 with sup-port arm 26. A linear motor 27 having a movable shaft 28 is secured to support arm 26. At its end remote from the motor ~-a~
27 the movable shaft 28 is connected -to a holder 29 for the flexible substrate 30. Holder 29 has a flexible cylindrical collar 31 which, at its end remote from the holder, has a widening 32 in which a vacuum duct 33 is provided. At its end remote from the holder 29, collar 31 is closed by a flexible diaphragm 34 which is mainly circular and has a central rec-essed portion 35. ~n this manner, an a:ir-tight space 39 is formed between holder 29, holder 31 and diaphragm 34, in which space an excessive gas pressure can be provided by suitable means, for example a pressure pump, which are not shown in the Figure, vla a perforation 36. ~Iolder 29 comprises a second perforation 37 extending through collar 31 into vacuum duct 33. By communicating holder 29 with a vacuum pump not shown, a sub-atmospheric pressur~ can be produced in duct 33 vla per-foration 37. As a result of said sub-atmospheric pressure the edge of the flexible substrate 30 is sucked against the widened portion 32 of collar 31. The flexible substrate 30 which has a central aperture 38 the dimension of which corresponds to ~` the inside dimension of the central recessed portion 35 of dia-phragm 34, will engage the non-recessed portion of diaphragm 34. The substrate 30 is manufactured from UV passing plastics, .
~or example polymethylmethacrylate (Plexiglass).
The operation of the device is as follows.
: As a result of an over pressure applied in space 25 39, the diaphragm 34 and the substrate 30 engaging it will be deformed spherosymmetrically. The assembly of holder 29, col-lar 34 and the spherosymmetrically vaulted diaphragm 34 with :~
substrate 30 is moved in the direction of the mould 20 with moulding resin 22 by means of motor 8. The part of the sub-strate 30 adjoining the circular aperture will first contact the annular quantity of moulding resin 22 which is situated .... - 13 .~.,.
~ ~ PHN 8712 around pin 21 on the mould 20. Substrate 30 with aperture 38 will centre around pin 21. The diameter of pin 21 corresponds to the diameter of aperture 38 and also to the inside diameter of recessed portion 35 o~ diaphragm 34. When the holder 2S
with diaphragm 34 and substrate 30 is further lowered, the moulding resin 22 will be rolled over mould 20 by means of the vaulted substrate 30 and spread over the surface of mould 20 with a circular fluid front. Deformation, that is flattening of the spherosymmetrically vaulted diaphragm 34 and substrate 30, will take place while furthermore pin 21 extends via aper-ture 3~ of substrate 30 in recessed portion 35 of diaphraym 34.
Figure 6 shows the situation in which the mould-ing resin 22 is partly spread over the surface o~ the mould.
The reference numerals used in Figure 6 correspond to those of Figure 5.
; When the fluid front of moulding resin 22 has nearly reached the edge of mould 20 and the diaphragm 34 with substrate 30 has nearly been deformed to a plane surface, air is admitted via performation 37 so that the sub-atmospheric pressure in the duct 33 is removed. As a result of this the substrate 30 will be uncoup:Led from holder 29 and the sub-strate, as a result of natural stress relief, will be stre~
` tched entirely and engage mould 20 in a plane sur~ace. The resin 22 is rolled entirely onto the edge of the mould 20.
The moulding resin 22 is cured with U~-light from ligh-t sources 40 via substrate 30 (Figure 7). The expos-ure is carried out in the same manner as described with refer-ence to Figure 3. It is to be noted that the support plate, the mould and the substrate preferably have the same outside diameters so that the excess of moulding resin after curing can easily be cut away without damaging the layer of resin ~6~ PHN 8712 between mould and substrate.
After curing, the resulting assembly of sub-strate 30 and the cured layer of mouldiny resin 42 haviny an information -track 41 (Figure 8) is removed frum the mould.
This removal may be carried out, for example, by placing the widened end 32 of collar 31 against the assembly, then pro-viding a sub-atmospheric pressure in vacuum duc-t 33 so that the assembly is sucked against collar 31, and then raising the holder 29 by means of the linear motor 27 80 that the assembly connected to holder 29 via collar 31 is pulled from mould 20.
Figure 8 shows the resulting plastics inform-ation carrier in which substrate 30 is bonded to the cured : layer of moulding resin 42 which has an information pattern 41. The plastics record carrier has a central aperture 43O
Reference numeral 44 in Figure 9 denotes a holder for sub-strate 45. The holder comprises a circular bo-ttom portion 46 which is connected at its edge to an upright cylindrical jacket 47. At its end remote from bottom portion 46 to jacket 47 has an inwardly directed flange 48 which in turn comprises at its free end an upright collar 49. At its end face the collar 49 has an annular vacuum duct 50 in which a ; sub-atmospheric pressure can be provided via perforation 51 and by means of the vacuum pump not shown. The perforation extends from the vacuum duct 50 axially through collar 49, then radially through flange 48 and jacket 47 ana opens into the outer surface of jacket 47.
Substrate 45 is sucked against the end face of collar 49 by using a sub-atmospheric pressure in duct 50.
An air-tight space 52 is enclosed by substrate 45, collar 49, .c'712 i 5 - Ll - 1 9 7 7 flan~e ~, jac,ke-t /1 7 cUlCI bo~-torn ~l6. ~ SllppOl't p1ate 53 o*
moul(l 5l~ is accolnnlodat,et,l -in spclce 5.~. Tlle sl-lp-p~rt pl;lt~
53 ha~ a f'lclnLr~;e por-tion ~5 wh-ich beLlrs on bottonl por-tlon l~6.
The diamet-*lr of`-rlange por-t:ion 55 cor-responds to the inside d:iarrlel;er of jacke-t 4 7 . rrhe mould 5LI which :is pro~idecl on the suppo,r-t p:late S3 ancl which :is parallel -to subs-tra-te 45, is providecl ceI)trally wi-th moulding resin 56. A sub-a-tmos-pher-ic pressure can be provided in the said air-tight space 52 via-perforation 57 by means of a vacuum pump, no-t shown.
The method accordingr to the in~rention carriecl out by means of this de~ice runs off as follows.
A sub-atmospheric pressure is provided ln space 52 v:La perforation 57. ~s a result of this, the substrate 45 whlch ls sucked against collar ~l9 wil] be deformed sphero syrnme-trically w:Lth simultan~ous elastic defortnation of collar 49. Dur:ing said deforlnation -the central portion of substrate 45 will contact the moulding resin 56 prcsent central1y on mould 54 and the subs-tra-te 45, when the sub-atmospheric pressure is increased, will then roll the moul-ding resin over the surface of mould 5~1 with a circular fluid front. Figure 10 shows the situa-tion ln which the sub-strate 45 has sprcad the mould:ing resin 55 over a part of mould 5 L~, The reference numer2ls :in Figure 10 correspond to those of Figure 9.
In the further continuous increase of the sub~
atmospheric pressure in space 52, elastic deformation of the flange Ll8 tal~es place so that the assem~ly of substra-te 45 with collar 49 and flange 4c~ is moved in the direction of mould 54. As a resul-t of' the increasecl pressure o~ the substrate 45 OIl the mould wi-th mouldillg resin 56, the moul--din~g resin will be further spreacl over the mouldO It will be ll-IN.S71~
15 ~ ) 7 '7 obv:i.ous i;h~t durirlg r :II.i.ng thc re.9:ill 56, the vaullecl sub--~strate 1I5 wi.]] colIt:i.nuousl.y be :f:L.IttenecI :froIn the cent:re.
~i`i.glI:re 11 sl~o~ci tllc s~ c1.t;:i.0:rl lrl which no Iu.:r--ther moveIlIent o~ substrate /I5~ collar 39 ~lnd Lla:rlge I~S -takes ~ ce a.ny lorIger. .The substrate ~5 has been.:tully ~la-tte~llecI
and bears agains-t the mou:LcI:ing resi.n 56 wlIich :is spreacl over the who:Le mou:Ld surrace .Cn -th:is situa-t:ion tI~le layer of oulding resin 56 is exposed to ultra~violet li.ght from light sources 58 and is cured. By graclually removing the sub-atmosph.eric pressure in space 52 ~lange l~c3 and coll.ar /~9 will gradua]ly return elast:ically -to -the original pos:ition in which the substrate 45 with the cured layer o~ moulding resin 56 bonded thereto is released :from the mould sur~ace.
~inally -the sub-atmosE)he:r:i.c pressIlre :i.:n duct 50 is removed 15 an.d the result:ing plact:ics record carrier can be removed from the holder 51~ ~s already s-tated above the resultil1.g record carrier ma~ be provided with a reflecting layer and a protective lacquer.
Claims (14)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of manufacturing a plastic record carrier having a stratified structure, comprising the steps of plac-ing a fluid moulding resin centrally on a surface of a mould having an information track, deforming a flexible substrate into a convex form bulging toward said mould, pressing the substrate against the moulding resin with a pressure force, the moulding resin thereby being rolled out over the surface of the mould with a circular fluid front, gradually changing the configuration of said substrate from said convex form to a planar form during the pressing step until the entire infor-mation track on the surface of the mould is covered by a relatively thin layer of the resin, curing the layer of resin, whereby the resin attaches itself to the substrate and releas-ing the assembly of substrate with attached layer of cured resin from the mould.
2. A method as claimed in Claim 1 further comprising the step of releasing the pressure force from the substrate when the fluid front has nearly reached the edge of the mould and while the substrate has not yet been deformed entirely to form a plane surface whereby the substrate pushes the fluid front towards the edge of the mould and engages the layer of resin without stress.
3. A method as claimed in Claim 1 wherein the resin is deposited centrally on the mould in the form of an annular layer.
4. A method as claimed in Claim 3 wherein the substrate has a central aperture, the diameter of the aperture corres-ponding to or being smaller than the inside diameter of the annular layer of resin deposited on the mould.
5. A method as claimed in Claim 1 wherein prior to said deforming step said substrate is a planar disc and is deformed into said convex shape by flexibly supporting the substrate along its entire periphery and then providing a different gas pressure on both sides of the substrate.
6. A method as claimed in Claim 5, wherein the differ-ence in gas pressure is variable and also provides the force with which the substrate is pressed against the moulding resin.
7. A method as claimed in Claim 1 wherein the resin is radiation-curable and said curing step includes the step of exposing said resin to ultraviolet radiation through the substrate.
8. The method as claimed in Claim 1 wherein said mould is made from metal.
9. A device for manufacturing a plastic record carrier having a stratified structure comprising mould means having an information track on a surface thereof for receiving a fluid moulding resin centrally on its surface, means for supporting a flexible substrate in opposed relationship with said mould, means for deforming said substrate into a convex form bulging toward said mould, means for pressing the sub-strate on the moulding resin with a pressure force, said deforming means and pressing means comprising means for rolling out the moulding resin over the surface of the mould with a circular fluid front, said deforming means and said pressing means further comprising means for gradually changing the configuration of said substrate from said convex form to a planar form during the pressing of the substrate against the resin, means for curing the layer of resin, whereby the resin attaches itself to the substrate, and means for releasing said substrate from said supporting means.
10. A device as claimed in Claim 9, further comprising a holder for the flexible substrate providing a holder sur-face in an area above the mould and provided with a gas connection, support plate beneath the mould for supporting the mould, a power source means for moving the holder relative to the support plate, the holder comprising an elastically deformable cylindrical collar provided at its annular end face remote from the holder with means to connect the sub-strate to the said collar along the circumference in a detach-able and air-tight manner.
11. A device as claimed in Claim 10 wherein the end face of the collar has at least one vacuum groove in which a sub-atmospheric pressure can be generated so that the substrate is drawn against the collar.
12. A device as claimed in Claim 10 wherein the cylind-rical collar at its annular end face is closed by a flexible diaphragm.
13. A device as claimed in Claim 12 wherein the dia-phragm has a central recessed portion and the mould further-more has a central boss, the boss fitting in the recessed portion of the diaphragm.
14. A device as claimed in Claim 10 wherein at its end remote from the substrate the collar has a projecting elast-ically deformable annular flange which at its free end is connected to a cylindrical jacket which at its end remote from the flange is closed by a bottom portion, the support plate with mould extends from the bottom portion into the space bounded by the jacket flange and collar, the mould being parallel to the substrate and the device comprising a vacuum connection, the substrate being deformed into a convex form by applying a sub-atmospheric pressure in the said space through said vacuum connection and being pressed against the mould under elastic deformation of collar and flange.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NLAANVRAGE7702702,A NL177721B (en) | 1977-03-14 | 1977-03-14 | METHOD FOR MANUFACTURING A PLASTIC INFORMATION CARRIER WITH LAYERED STRUCTURE AND AN APPARATUS FOR CARRYING OUT THE METHOD |
| NL7702702 | 1977-03-14 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1106560A true CA1106560A (en) | 1981-08-11 |
Family
ID=19828162
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA298,551A Expired CA1106560A (en) | 1977-03-14 | 1978-03-09 | Method of manufacturing a plastics record carrier having a stratified structure as well as a device for carrying out the method |
Country Status (11)
| Country | Link |
|---|---|
| US (1) | US4312823A (en) |
| JP (1) | JPS53116105A (en) |
| AT (1) | AT357798B (en) |
| AU (1) | AU522151B2 (en) |
| CA (1) | CA1106560A (en) |
| DE (1) | DE2809161C3 (en) |
| ES (1) | ES467783A1 (en) |
| FR (1) | FR2384404A1 (en) |
| GB (1) | GB1581511A (en) |
| IT (1) | IT1093215B (en) |
| NL (1) | NL177721B (en) |
Families Citing this family (70)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3934298A (en) * | 1974-04-23 | 1976-01-27 | Kim James S H | Toothbrush |
| DE2966968D1 (en) * | 1978-08-28 | 1984-06-14 | Discovision Ass | Method for moulding a videodisc composition |
| FR2450683A1 (en) * | 1979-03-06 | 1980-10-03 | Thomson Brandt | METHOD AND APPARATUS FOR MAKING VIDEO DISC |
| NL7904113A (en) * | 1979-05-25 | 1980-11-27 | Philips Nv | OPTICALLY READABLE INFORMATION DISC, METHOD FOR MANUFACTURING IT, AND APPARATUS FOR PERFORMING THIS METHOD |
| NL7906117A (en) * | 1979-08-10 | 1981-02-12 | Philips Nv | METHOD AND APPARATUS FOR MANUFACTURING A PLASTIC INFORMATION CARRIER |
| FR2468456A1 (en) * | 1979-09-06 | 1981-05-08 | Thomson Csf | DEVICE FOR MOLDING INFORMATION CARRIER DISCS |
| JPS5677905A (en) * | 1979-11-28 | 1981-06-26 | Matsushita Electric Ind Co Ltd | Disk record |
| JPS5687203A (en) * | 1979-12-18 | 1981-07-15 | Toppan Printing Co Ltd | Manufacture of disk |
| JPS56157021U (en) * | 1980-04-22 | 1981-11-24 | ||
| JPS56167422A (en) * | 1980-05-30 | 1981-12-23 | Toppan Printing Co Ltd | Manufacturing device for high-density information recording carrier |
| US4414316A (en) * | 1980-09-05 | 1983-11-08 | Rexham Corporation | Composite lenticular screen sheet |
| EP0047645B1 (en) * | 1980-09-05 | 1984-11-28 | Matsushita Electric Industrial Co., Ltd. | A method of producing an information recording disk |
| JPS5756314U (en) * | 1980-09-18 | 1982-04-02 | ||
| US4363844A (en) * | 1980-09-22 | 1982-12-14 | Lewis Terry W | Metallized information carrying discs |
| US4449916A (en) * | 1980-11-20 | 1984-05-22 | Matsushita Electric Industrial Co., Ltd. | Device for manufacturing information recording mediums |
| NL8101515A (en) * | 1981-03-27 | 1982-10-18 | Philips Nv | OPTICALLY READABLE INFORMATION DISC AND METHOD FOR MANUFACTURING IT. |
| JPS57163533A (en) * | 1981-04-01 | 1982-10-07 | Toppan Printing Co Ltd | Preparation of information recording carrier |
| JPS57163534A (en) * | 1981-04-02 | 1982-10-07 | Toppan Printing Co Ltd | Preparation of information recording carrier |
| JPS57163535A (en) * | 1981-04-02 | 1982-10-07 | Toppan Printing Co Ltd | Preparation of information recording carrier |
| JPS57163536A (en) * | 1981-04-02 | 1982-10-07 | Toppan Printing Co Ltd | Preparation of information recording carrier |
| US4447201A (en) * | 1981-06-29 | 1984-05-08 | Clean-Tex A/S | Vulcanizing press for vulcanizing flat articles |
| FR2513934A1 (en) * | 1981-10-06 | 1983-04-08 | Thomson Csf | METHOD FOR DISMANTLING INFORMATION CARRIER DISK AND DEVICE USING SUCH A METHOD |
| JPS5862021A (en) * | 1981-10-08 | 1983-04-13 | Toppan Printing Co Ltd | Manufacture of high density information record carrier |
| FR2514689B1 (en) * | 1981-10-21 | 1986-05-23 | Souriau & Cie | PROCESS FOR PREPARING WITH PRECISION A PART HAVING HOLLOW AND / OR PROJECTING PARTS AND PRODUCT OBTAINED BY THIS PROCESS |
| FR2516286A1 (en) * | 1981-11-06 | 1983-05-13 | Thomson Csf | METHOD OF OBTAINING A COPY-DISK FROM AN ORIGINAL ENGRAVING CARRIED BY A MATRIX |
| JPS5882726A (en) * | 1981-11-12 | 1983-05-18 | Toppan Printing Co Ltd | Manufacture of high-density information carrier |
| JPS5884730A (en) * | 1981-11-13 | 1983-05-20 | Sanyo Electric Co Ltd | Manufacture of disk record |
| NL8300417A (en) * | 1983-02-04 | 1984-09-03 | Philips Nv | METHOD AND APPARATUS FOR MANUFACTURING A PLASTIC INFORMATION CARRIER WITH A LAYERED STRUCTURE |
| JPS6066344A (en) * | 1983-09-21 | 1985-04-16 | Toshiba Corp | Optical disc |
| IT1175178B (en) * | 1983-11-15 | 1987-07-01 | Omv Spa Off Mecc Veronese | EXTRACTOR OF OBJECTS OBTAINED WITH THERMOFORMING MACHINES |
| JPS60122138A (en) * | 1983-12-06 | 1985-06-29 | Pioneer Electronic Corp | Apparatus for manufacturing information recording disc |
| JPS60224532A (en) * | 1984-04-23 | 1985-11-08 | Matsushita Electric Ind Co Ltd | Manufacture of information recording carrier |
| EP0168530B1 (en) * | 1984-07-05 | 1990-04-04 | Docdata N.V. | Method and apparatus for reproducing relief structures onto a substrate |
| JPH0740378B2 (en) * | 1984-12-07 | 1995-05-01 | 株式会社日立製作所 | Method and device for duplicating information record carrier |
| US4724023A (en) * | 1985-04-09 | 1988-02-09 | E M Partners Ag | Method of making laminated glass |
| NL8501148A (en) * | 1985-04-19 | 1986-11-17 | Optical Storage Int | METHOD FOR APPLYING AN OPTICALLY DETECTABLE STRUCTURE TO THE SUBSTRATE OF AN OPTICALLY READABLE INFORMATION DISC, DIES FOR THE METHOD, DEVICE FOR CARRYING OUT THE METHOD AND PROMOTED DATA PROCESSED. |
| JPS6392438A (en) * | 1986-10-07 | 1988-04-22 | Pioneer Electronic Corp | Apparatus for forming transfer layer of information recording disc |
| JPS6378314U (en) * | 1986-11-11 | 1988-05-24 | ||
| JPS6378313U (en) * | 1986-11-11 | 1988-05-24 | ||
| JPS63109856U (en) * | 1986-12-26 | 1988-07-15 | ||
| DE3719200A1 (en) * | 1987-06-09 | 1988-12-29 | Ibm Deutschland | OPTICAL DISK AND METHOD FOR THEIR PRODUCTION |
| DE3826234A1 (en) * | 1988-08-02 | 1990-02-08 | Kulzer & Co Gmbh | CIRCUIT ARRANGEMENT FOR OPERATING A LOW-PRESSURE GAS DISCHARGE LAMP |
| JP2570402B2 (en) * | 1988-09-30 | 1997-01-08 | 日本ビクター株式会社 | Optical information recording medium molding device |
| NL9002517A (en) * | 1990-11-19 | 1992-06-16 | Philips Nv | METHOD FOR MANUFACTURING AN OPTICALLY READABLE PLATE AND APPARATUS FOR CARRYING OUT THE METHOD |
| NL9100366A (en) * | 1991-02-28 | 1992-09-16 | Philips & Du Pont Optical | METHOD FOR MANUFACTURING A DISC-SHAPED DATA CARRIER, DATA CARRIER MADE ACCORDING TO THE METHOD AND DEVICE FOR CARRYING OUT THE METHOD |
| US5857358A (en) * | 1996-10-23 | 1999-01-12 | Donnelly Corporation | Method and apparatus for bending glass |
| US5938810A (en) | 1996-10-23 | 1999-08-17 | Donnelly Corporation | Apparatus for tempering and bending glass |
| CN100391711C (en) * | 2001-05-22 | 2008-06-04 | 日立麦克赛尔株式会社 | Injection molding method |
| ITTO20010823A1 (en) * | 2001-08-22 | 2003-02-22 | Taltos S P A | PROCESS FOR THE CONSTRUCTION OF A STONE-GLASS COMPOSITE PANEL AND PANEL OBTAINED WITH SUCH PROCESS. |
| TW531742B (en) * | 2001-10-30 | 2003-05-11 | Ritek Corp | Manufacturing method for disk cover layer |
| US7179079B2 (en) * | 2002-07-08 | 2007-02-20 | Molecular Imprints, Inc. | Conforming template for patterning liquids disposed on substrates |
| US20080160129A1 (en) * | 2006-05-11 | 2008-07-03 | Molecular Imprints, Inc. | Template Having a Varying Thickness to Facilitate Expelling a Gas Positioned Between a Substrate and the Template |
| US7019819B2 (en) * | 2002-11-13 | 2006-03-28 | Molecular Imprints, Inc. | Chucking system for modulating shapes of substrates |
| US7641840B2 (en) * | 2002-11-13 | 2010-01-05 | Molecular Imprints, Inc. | Method for expelling gas positioned between a substrate and a mold |
| US7790231B2 (en) * | 2003-07-10 | 2010-09-07 | Brewer Science Inc. | Automated process and apparatus for planarization of topographical surfaces |
| EP1538482B1 (en) * | 2003-12-05 | 2016-02-17 | Obducat AB | Device and method for large area lithography |
| JP4393244B2 (en) * | 2004-03-29 | 2010-01-06 | キヤノン株式会社 | Imprint device |
| EP1594001B1 (en) * | 2004-05-07 | 2015-12-30 | Obducat AB | Device and method for imprint lithography |
| DE102004028501B3 (en) * | 2004-06-11 | 2006-05-04 | Maschinenfabrik Lauffer Gmbh & Co Kg | Press, in particular laminating press |
| US7798801B2 (en) * | 2005-01-31 | 2010-09-21 | Molecular Imprints, Inc. | Chucking system for nano-manufacturing |
| JP4820099B2 (en) | 2005-03-01 | 2011-11-24 | 株式会社リコー | Flexible transfer body and method for manufacturing flexible optical disk |
| US8215946B2 (en) | 2006-05-18 | 2012-07-10 | Molecular Imprints, Inc. | Imprint lithography system and method |
| US7830498B2 (en) * | 2006-10-10 | 2010-11-09 | Hewlett-Packard Development Company, L.P. | Hydraulic-facilitated contact lithography apparatus, system and method |
| CN101808808B (en) | 2007-09-28 | 2013-05-01 | 东丽株式会社 | Method and device for manufacturing sheet having fine shape transferred thereon |
| JP5411557B2 (en) * | 2009-04-03 | 2014-02-12 | 株式会社日立ハイテクノロジーズ | Microstructure transfer device |
| US8913230B2 (en) * | 2009-07-02 | 2014-12-16 | Canon Nanotechnologies, Inc. | Chucking system with recessed support feature |
| FR2965974B1 (en) * | 2010-10-12 | 2013-11-29 | Soitec Silicon On Insulator | PROCESS FOR MOLECULAR BONDING OF SILICON AND GLASS SUBSTRATES |
| NL2016593B1 (en) * | 2016-04-12 | 2017-11-01 | Iai Ind Systems B V | Method and apparatus for applying a layer having a relief on a flat face of a substrate. |
| CN107322854B (en) * | 2017-07-13 | 2020-01-03 | 上海航天控制技术研究所 | Magnetic code disc Hall device, preparation method thereof and glue filling mold |
| WO2020112835A1 (en) * | 2018-11-26 | 2020-06-04 | Edge Embossing, Inc. | Thermoplastic forming tools, assemblages thereof, and methods of making and methods of use thereof |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1209308A (en) * | 1913-03-27 | 1916-12-19 | Edmond Lanhoffer | Apparatus for molding objects by pressure. |
| US1260002A (en) * | 1913-03-28 | 1918-03-19 | Edmond Lanhoffer | Apparatus for molding objects by pressure. |
| US2441097A (en) * | 1946-06-15 | 1948-05-04 | Owens Corning Fiberglass Corp | Plastics molding apparatus |
| US2565949A (en) * | 1947-04-12 | 1951-08-28 | Walter B Clifford | Process and apparatus for molding sheet material |
| US2991600A (en) * | 1957-08-26 | 1961-07-11 | Talbot A Lancaster | Method and apparatus for vacuum packaging with plastic sheaths |
| NL239956A (en) * | 1958-06-13 | |||
| US2962757A (en) * | 1958-12-18 | 1960-12-06 | Gen Tire & Rubber Co | Method of and apparatus for molding and vulcanizing a fabric reinforced rubber air spring bellows |
| US2968064A (en) * | 1959-06-24 | 1961-01-17 | Gen Motors Corp | Clamping frame for vacuum forming parts |
| US3112570A (en) * | 1960-06-06 | 1963-12-03 | Vasconcellos Decio Fernande De | Optical set |
| FR1507289A (en) * | 1966-11-16 | 1967-12-29 | Pathe Marconi Ind Music | Method and device for the production of phonographic records by injection |
| BE754422A (en) * | 1969-08-13 | 1971-02-05 | Shell Int Research | METHOD AND DEVICE FOR FORMING OBJECTS FROM A SHEET |
| US3594877A (en) * | 1969-10-24 | 1971-07-27 | Yuken Kogyo Co Ltd | Apparatus for manufacturing ceramic articles |
| BE793335A (en) * | 1971-12-27 | 1973-04-16 | Teldec Telefunken Decca | DEVICE FOR MARKING INFORMATION BEARERS CONSISTING OF A SHEET OF SYNTHETIC MATERIAL. |
| NL7212045A (en) * | 1972-09-05 | 1974-03-07 | ||
| NL164688C (en) * | 1973-10-15 | 1981-01-15 | Mca Disco Vision | METHOD FOR MANUFACTURING A VIDEO DISC IN WHICH A FORM IS FIRST MANUFACTURED |
-
1977
- 1977-03-14 NL NLAANVRAGE7702702,A patent/NL177721B/en not_active IP Right Cessation
-
1978
- 1978-03-03 DE DE2809161A patent/DE2809161C3/en not_active Expired
- 1978-03-09 CA CA298,551A patent/CA1106560A/en not_active Expired
- 1978-03-10 IT IT21103/78A patent/IT1093215B/en active
- 1978-03-10 AU AU34071/78A patent/AU522151B2/en not_active Expired
- 1978-03-10 GB GB9551/78A patent/GB1581511A/en not_active Expired
- 1978-03-11 JP JP2819078A patent/JPS53116105A/en active Granted
- 1978-03-11 ES ES467783A patent/ES467783A1/en not_active Expired
- 1978-03-13 AT AT177878A patent/AT357798B/en not_active IP Right Cessation
- 1978-03-14 FR FR7807293A patent/FR2384404A1/en active Granted
-
1980
- 1980-02-26 US US06/124,878 patent/US4312823A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| FR2384404B1 (en) | 1984-05-18 |
| JPS618762B2 (en) | 1986-03-17 |
| FR2384404A1 (en) | 1978-10-13 |
| NL177721B (en) | 1985-06-03 |
| ES467783A1 (en) | 1978-10-16 |
| IT7821103A0 (en) | 1978-03-10 |
| IT1093215B (en) | 1985-07-19 |
| US4312823A (en) | 1982-01-26 |
| DE2809161A1 (en) | 1978-09-21 |
| AT357798B (en) | 1980-07-25 |
| ATA177878A (en) | 1979-12-15 |
| AU522151B2 (en) | 1982-05-20 |
| NL7702702A (en) | 1978-09-18 |
| JPS53116105A (en) | 1978-10-11 |
| AU3407178A (en) | 1979-09-13 |
| DE2809161B2 (en) | 1980-07-10 |
| DE2809161C3 (en) | 1985-11-21 |
| GB1581511A (en) | 1980-12-17 |
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| MKEX | Expiry |