CA2107171A1 - Self sealing film - Google Patents
Self sealing filmInfo
- Publication number
- CA2107171A1 CA2107171A1 CA002107171A CA2107171A CA2107171A1 CA 2107171 A1 CA2107171 A1 CA 2107171A1 CA 002107171 A CA002107171 A CA 002107171A CA 2107171 A CA2107171 A CA 2107171A CA 2107171 A1 CA2107171 A1 CA 2107171A1
- Authority
- CA
- Canada
- Prior art keywords
- less
- self sealing
- weight percent
- film
- sealing film
- 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
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K3/00—Materials not provided for elsewhere
- C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
-
- 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
- B29C73/00—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D
- B29C73/16—Auto-repairing or self-sealing arrangements or agents
- B29C73/163—Sealing compositions or agents, e.g. combined with propellant agents
-
- 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
- B29C73/00—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D
- B29C73/16—Auto-repairing or self-sealing arrangements or agents
- B29C73/18—Auto-repairing or self-sealing arrangements or agents the article material itself being self-sealing, e.g. by compression
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D7/00—Producing flat articles, e.g. films or sheets
- B29D7/01—Films or sheets
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
- C09K2200/06—Macromolecular organic compounds, e.g. prepolymers
Abstract
ABSTRACT OF THE DISCLOSURE
The present invention is directed toward a water vapor responsive self sealing thin film which is formed from a blend of at least about 75 weight percent of a water dispersible polymer; from about 0.5 to about 5 weight percent of a xerogellant; and from about 7.5 to about 20 weight percent of a plasticizing agent. The film has the ability to self seal and close apertures in the film in the presence of water. The film will be useful in many applications, including in the formation of a tent fabric where the film could be applied to a slightly apertured fabric and the film would self seal in response to contact with water or water vapor.
The present invention is directed toward a water vapor responsive self sealing thin film which is formed from a blend of at least about 75 weight percent of a water dispersible polymer; from about 0.5 to about 5 weight percent of a xerogellant; and from about 7.5 to about 20 weight percent of a plasticizing agent. The film has the ability to self seal and close apertures in the film in the presence of water. The film will be useful in many applications, including in the formation of a tent fabric where the film could be applied to a slightly apertured fabric and the film would self seal in response to contact with water or water vapor.
Description
FIELD OF THE INVENTION
The field of the present invention is that of film materials which, if 5 apertured, have the ability to self seal.
BACKGROUND OF THE INVENTION
'; . ""' .
For quite some time those in the art have been searching for a film ~
... . -10 material which, if apertured, has the ability to self seal and close the apertures in the presence of water vapor. Such a film would have considerable usefulness in a wide variety of areas. An exemplary area of application of such a material would be in the formation of tent fabric.
If the fabric was slightly apertured, a film which would self seal in 15 response to contact with water or water vapor would be highly desirable.
During experimentation directed to measuring the water vapor transmission rate (\NVTR) of various apertured film materials we observed that certain commercially available trash bags, when 20 apertured, self sealed during the WVTR test. We hypothesized that this action was due to the presence of an additive or additives to the film . .
which was not normally present in poiyethylene trash bags. Possible components of this sort were starch and iron oxide. We were able to ;
check the possibility of whether starch, by itself, was the self sealing ~` ~
,. ~. ..
' :, ~ ,.'. '~ .
,,~"~,...
A . , . ' : , ' ~--` 21~7~7~
factor by testing commercially available film containing starch as an additive but not iron. As aperture closure did not occur, we concluded that starch, by itself, did not appear to be the component causing the observed result. Plastic film containing only iron oxide as an additive 5 is not known to us to be commercially available. However, it is known that, under certain conditions, Fe2O3 in the presence of water will form a hydroxide Fe(OH)3 which is a sol. This material by itself or in the presence of starch would flocculate and explain the observed aperture sealing. It should be noted that other metal hydroxides exhibit similar 10 behavior to iron. Accordingly, we set out to determine if a self sealing film could be formed from a polymer system containirig a small amount of a gelling/swelling agent as a simpler method of achieving the results observed with the iron starch system. ~ ~
Prior documents in this area include U.S. patent number 4,913,517 - ~ -15to Arroyo et al., U.S. patent number 3,890,974 to Kozak, Canadian patent application number 2,005,764 to Bottiglione et al., European patent application number 0 378 940 A1, Kolloid Aeitschrift V-74, pp.
20~205 (1936) and The Principles of Colloid and Surface Chemistry.
second edition, by P.C. Hiemenz, pp 782-783 (1986).
: ';, ' ::
107~
OBJECTS OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a thin film which readily self seals small apertures in the 5 presence of water vapor or water.
Still further objects and the broad scope of applicability of the present invention will become apparent to those of skill in the art from the details given hereinafter. However, it should be understood that the detailed description of the presently preferred embodiment of the 10 present invention is given only by way of illustration because various changes and modifications well within the spirit and scope of the invention will become apparent to those of skill in the art in view of the following description.
DEFINITIONS
As used herein the term xerogellant refers to a material which, . . ; . . .
when in a substantially dry state, has the ability to spontaneously imbibe at least about twenty (20) times its own weight in aqueous fluid.
Importantly, the xerogellant should have the ability to generally retain its ` `
original identity after it has imbibed the fluid. For example, a bead, fiber or film formed from a xerogellant will still be recognizable as such after having imbibed the fluid.
- . . -. .
" . ...
.. : , . . ~ .. , .. ., . .. .... , .. ~ . . . . . . .. .
The field of the present invention is that of film materials which, if 5 apertured, have the ability to self seal.
BACKGROUND OF THE INVENTION
'; . ""' .
For quite some time those in the art have been searching for a film ~
... . -10 material which, if apertured, has the ability to self seal and close the apertures in the presence of water vapor. Such a film would have considerable usefulness in a wide variety of areas. An exemplary area of application of such a material would be in the formation of tent fabric.
If the fabric was slightly apertured, a film which would self seal in 15 response to contact with water or water vapor would be highly desirable.
During experimentation directed to measuring the water vapor transmission rate (\NVTR) of various apertured film materials we observed that certain commercially available trash bags, when 20 apertured, self sealed during the WVTR test. We hypothesized that this action was due to the presence of an additive or additives to the film . .
which was not normally present in poiyethylene trash bags. Possible components of this sort were starch and iron oxide. We were able to ;
check the possibility of whether starch, by itself, was the self sealing ~` ~
,. ~. ..
' :, ~ ,.'. '~ .
,,~"~,...
A . , . ' : , ' ~--` 21~7~7~
factor by testing commercially available film containing starch as an additive but not iron. As aperture closure did not occur, we concluded that starch, by itself, did not appear to be the component causing the observed result. Plastic film containing only iron oxide as an additive 5 is not known to us to be commercially available. However, it is known that, under certain conditions, Fe2O3 in the presence of water will form a hydroxide Fe(OH)3 which is a sol. This material by itself or in the presence of starch would flocculate and explain the observed aperture sealing. It should be noted that other metal hydroxides exhibit similar 10 behavior to iron. Accordingly, we set out to determine if a self sealing film could be formed from a polymer system containirig a small amount of a gelling/swelling agent as a simpler method of achieving the results observed with the iron starch system. ~ ~
Prior documents in this area include U.S. patent number 4,913,517 - ~ -15to Arroyo et al., U.S. patent number 3,890,974 to Kozak, Canadian patent application number 2,005,764 to Bottiglione et al., European patent application number 0 378 940 A1, Kolloid Aeitschrift V-74, pp.
20~205 (1936) and The Principles of Colloid and Surface Chemistry.
second edition, by P.C. Hiemenz, pp 782-783 (1986).
: ';, ' ::
107~
OBJECTS OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a thin film which readily self seals small apertures in the 5 presence of water vapor or water.
Still further objects and the broad scope of applicability of the present invention will become apparent to those of skill in the art from the details given hereinafter. However, it should be understood that the detailed description of the presently preferred embodiment of the 10 present invention is given only by way of illustration because various changes and modifications well within the spirit and scope of the invention will become apparent to those of skill in the art in view of the following description.
DEFINITIONS
As used herein the term xerogellant refers to a material which, . . ; . . .
when in a substantially dry state, has the ability to spontaneously imbibe at least about twenty (20) times its own weight in aqueous fluid.
Importantly, the xerogellant should have the ability to generally retain its ` `
original identity after it has imbibed the fluid. For example, a bead, fiber or film formed from a xerogellant will still be recognizable as such after having imbibed the fluid.
- . . -. .
" . ...
.. : , . . ~ .. , .. ., . .. .... , .. ~ . . . . . . .. .
2~ ~7~
As used herein the term water dispersible polymer refers to a polymeric material which is capable of forming a dispersion in an aqueous medium at ambient temperature.
As used herein the term "plasticizing agent refers to an organic compound which, when added to a high polymer, may increase the ease of processing the high polymer or increase the toughness and flexibility of the high polymer after processing. A plasticizing agent may be able to accomplish all of these.
As used herein the term "thin film" refers to a film having an averagethicknessoflessthanabout10 mils. Forexample,thethinfilm may have an average thickness of less than about 5 mils. More particularly, the thin film may have an average thickness of less than about 1 mil. Average thickness is determined by five (5) random measurements of the film and averaging the results.
As used herein the term "self sealing thin film" or "self sealable thTn film" refers to a thin film which, in the presence of water vapor, has ability to seal apertures having an area of less than about 625,000 square microns.
As used herein the term "aperture" refers to holes having an area of less than about 625,000 square microns. For example, an aperture may have an area of from about 10 to about 625,000 square microns.
More particularly, an aperture may have an area of from about 100 to ~7~
' :
about 235,000 square microns. Even more particularly, an aperture may have an area of from about 500 to about 10,000 square microns.
SUMMARY OF THE INVENTION
The present invention is directed toward a film material which, if apertured, has the ability, in the presence of water vapor or water, to self seal the apertures if they have an area of less than about 625,000 square microns. The material includes at least about 75 weight percent 10 of a water dispersible polymer; from about 0.5 to about 5 weight percent of a xerogellant and from about 7.5 to about 20 weight percent of aplasticizing agent.
In some embodiments the self sealing film material may include at Ieast about 81 weight percent of a water dispersible polymer; from 15 about 1 to about 4 weight percent of a xerogellant and from about 10 to about 15 weight percent of a plasticizing agent. For example, the self sealing film material may include at least about 83 weight percent of a water dispersible polymer; from about 2 to about 3 weight percent of a xerogellant and from about 11 to about 14 weight percent of a . .. ...
20 plasticizing agent. Moreparticularly,theself sealingfilm material may include at least about 84.5 weight percent of a water dispersible polymer; about 2.5 weight percent of a xerogellant and about 13 weight percent of a plasticizing agent.
.- -~ ,.
~ -~''.' .".'' ';
~717~
In some embodiments the water dispersible polymer may be selected from the group including high molecular weight amorphous polyesters having one or more ionic substituents attached thereto. In other embodiments the water dispersible polymer may be selected from 5 the group including elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof. In one embodiment the water dispersible polymer is an elastomeric emulsion which includes about 50% latex, about 50% water, less than about 0.01% acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01%
ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
In some embodiments the xerogellant may be selected from the group including sodium carboxymethyl cellulose, derivatives of sodium 15 carboxymethyl cellulose, poly(acrylic acid) salts, (ethylene oxide), acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate) and polyisobutylen~co-disodium maleate.
In some embodiments the plasticizing agent may be selected from the group including glycerin, sorbitol, glucidol, sucrose, ethylene glycol, 20 propylene glycol, diethylene glycol, polyethylene glycol, acid amides, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone.
In some embodiments the thin film ~ ial~i~ capable of self sealing apertures having an area of less than about 625,000 square microns in the presence of 75 percent relative humidity in about 30 seconds. For example, the thin film material may be capable of self sealing apértures having an area of less than about 235,000 square microns in the presence of 50 percent relative humidity in about 30 seconds. More particularly, the thin film material may be capable of self sealing apertures having an area of less than about 10,000 square microns in the presence of 50 percent relative humidity in about 15 seconds. -BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood with reference to the attached drawings in which:
, Figure 1 is a photomicrograph of an apertured film :
sample prepared as described in Example I and exposed to 100 percent steam as described in Example II; ~ -Figure 2 is a photomicrograph of the film sample of Figure 1 showing the closed aperture after 15 seconds `.
exposure to the steam;
' ', ', ., :. ' Figure 3 is a photomicrograph of an apertured film ~ ; - .
sample prepared as described in Example I and exposed . .
to 100 percent steam as described in Example III; and :
Figure 4 is a photomicrograph of the film sample of . :~
Figure 1 showing the closed aperture after 5 seconds exposure to the steam.
2~7~ 71 DETAILED DESCRIPTION OF THE INVENTION
The self sealing film material of the present invention is formed by placing the xerogellant, preferably in powder form, in an appropriately sized container and adding water so that the xerogellant is fully hydrated. While any material meeting the definition of a xerogellant may be utilized, exemplary xerogellants include sodium carboxymethyl cellulose, poly(acrylic acid) salts, radiation crosslinked poly(ethylene oxide), carboxymethyl cellulose, acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate) and polyisobutylene-co-disodium maleate. One xerogellant is a starch 7(a) 2~7~7~
grafted sodium polvacrylate which may be obtained from Hoechst CelaneseCorporation underthetrade mark SanwetlM5000P.
If the consistency of the xerogellant and water mixture is not that of a fluid, additional water is added until such is the case. This action 5 is only necessary with certain xerogellants. It is to the fluidized xerogellant that the water dispersible polymer and the plasticizing agent are added. The water dispersible polymer may be added to the hydrated xerogellant as an aqueous dispersion.
While any film forming water dispersible polymer may be utilized, 10 exemplary film forming water dispersible polymers include such polymers chosen from the group including high molecular weight , amorphous polyesters having one or more ionic substituents attached thereto. This type of polymer is available form the Eastman Chemical Co.ofKingsport,Tennessee,underthetrade mark EastmanAQD
15 In particular, Eastman AQ 55D and AQ 38D. Alternatively the water dispersible polymer may be selected from the group including elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof. Exemplary elastomeric emulsions may beobtained , , . .:
20 from the B.F. Goodrich Co., Specialty Polymers & Chemicals Division under the trade mark HyStretch~. HyStretch~ elastomeric emulsions typically are a blend of about 50% latex, about 50% water, less than about 0.01% acrylamide, less than about 1.0% ammonium 2 :~ ~ 7 ~ 7 ~
hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1%
formaldehyde and less than about 0.0025% N-methylolacrylamide.
While any suitable plasticizing agent may be utilized, exemplary plasticizing agents include glycerin, sorbitol, glucidol, sucrose, ethylene 5 glycol, propylene glycol, diethylene glycol, polyethylene glycol, acid amides, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone. One exemplary plasticizing agent is glycerin which may be obtained from Fischer Scientific of Fairtown, New Jersey, under the trade mark G-33-1.
After the three components have been thoroughly mixed, they are cast, in conventional manner, in a film forming mold. Thereafter the water is removed by natural evaporation which, if desired, may be assisted by low grade heating of the cast mixture.
Discounting the water which is evaporated away, the xerogellant, 15 the film forming waterdispersible polymer and the plasticizing agent are blended together in a conventional manner so that the final weight percentage of these components, after removal of the water by evaporation, is at least about 81 weight percent of the water dispersible polymer; from about 1 to about 4 weight percent of the xerogellant:
20 and from about 10 to about 15 weight percent of the plasticizing agent.
More particularly, the final weight percentages of these components of the material may range from at least about 83 weight percent of the water dispersible polymer; from about 2 to about 3 weight percent of ~07~
, .
the xerogellant; and from about 11 to about 14 weight percent of the plasticizing agent. Even more particularly, the final weight percentages of these components may range from at least about 84.5 weight percent of the water dispersible polymer; about 2.5 weight percent of 5 the xerogellant; and about 13 weight percent of the plasticizing agent.
Those of skill in the art will readily recognize that the self sealing thin film material may be formed by other methods. For example, the material may be formed by extrusion methods.
The invention will now be described with respect to certain specific 10 embodiments thereof.
EXAMPLE I
About 0.352 grams of Sanwet IM500P xerogellant was combined with a~out 300 milliliters of water in a 600 milliliter beaker. The solution was stirred gently and the xerogellant was allowed to hydrate for sixty (60) minutes. The xerogellant swelled and a clear gel formed in the beaker. After 60 minutes, the gel was poured into a Waring blender model no. 7011 and mixed at high speed for about one minute, 20 resulting in a "liquified"solution. This liquified solution was poured back into the 600 milliliter beaker and about 24.26 grams of a 28% solution (6.79 grams of polymer) of water dispersible polymer obtained under the trade mark AQ55D form the Eastman Chemical Co. was * Trade-mark 10 ~ ~ :
, ' ~, ~107~7~
-added. Also added at this time was 1.068 grams of glycerol, a plasticizing agent, obtained under the trade mark G 33-1 from the Fischer Scientific Corp.
The mixture was stirred by hand gently with a glass stir rod and 5 then stirred mechanically with a magnetic stir bar until thoroughly mixed. Once mixed thoroughly, the solution was poured into two (2) individual wax molds, both measuring 0.5 inches deep, 4.0 inches wide and 8.0 inches long. The molds were machined from blocks ot wax by the McKellco Corp. of Alpharetta, Georgia. The solutions were 10 dehydrated initially in a micro/convection oven at 180 degrees Fahrenheit for one hour in order to speed up the evaporation process.
The molds were then removed from the oven and the films they contained were dried over desiccant for four (4) days until dry. A film having a thickness of about eight (8) mils was obtained.
The dried films were gently removed form each of the wax blocks and cut into small circles (having a diameter of three(3) inches) for testing and evaluation of the film's self sealing capabilities.
. ~ .
EXPERIMENTAL TESTING OF SELF SEALING CAPABIUTY
Apertures were made in the three inch diameter film samples by ~;
mechanically punching them with 200 needles bundled together in a one (1) inch diameter circle. The needle bundle was placed on top of 7 ~
the film so that the center of the needle bundle was located generally at the center of the sample and the bundle was gently tapped wlth a hammer until the needles cleanly broke through the film leaving behind about 200 apertures per square inch having diameters of from about 150 to about 250 microns. The diameters of the apertures were measured using conventional photomicrography equipment. One aperture, measured to be about 190 microns was selected and marked for the self sealing experiment.
The apertured sample was then sandwiched between two (2) impervious films each having a one (1) inch diameter circular aperture cut in the center of them. This sandwich was then mounted in a water vapor transmission test cup having a diameter of about 2.5 inches and containing about 100 milliliters of water. The cup and its contents were placed in a controlled temperature/humidity oven a 100 degrees Fahrenheit and 50 percent relative humidity.
After 15 minutes, the sample film was removed from the oven and removed from the 'sandwich". The 190 micron aperture was now closed.
This example was repeated with a film of essentially pure AQ 55D
and the aperture did not close.
:,,~'.
,~
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EXAMPLE ll Another of the apertured samples prepared as described in Example 1, was exposed to 100 percent steam. The steam was 5 provided by boiling water in aPyrex*dish on a hot plate. A 250 micron aperture was selected and photomicrographed for this experiment.
Figure 1 is this photomicrograph. After 15 seconds in the steam environment, the aperture had closed as indicated by the after"
photomicrograph, Figure 2.
EXAMPLE lll In an effort to determine how rapidly the aperture closed or "self-sealed", Example ll was repeated with the apertured film being removed 15 from the steam environment in five (5) seconds. This is as rapid as this taskcould be accomplished.
Figure 3 is the 'before photomicrograph of the aperture of i_xample lll. Upon removing the sample from the steam environment after five (5) seconds, the aperture had c!osed as indicated by the "after"
20 photomicrograph, Figure4.
For comparison purposes, this experimentwas repeatedwith afilm of essentially pure AQ 55D and the aperture did not close up.
.. ' ,,.. - . ,.
* Trade-mark 13 Xl~7~
While the invention has been described in detail with respect to specific preferred embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to and variations of the preferred 5 embodiments. Such alterations and variations are believed to fall within the scope and spirit of the invention and the appended claims.
~ -
As used herein the term water dispersible polymer refers to a polymeric material which is capable of forming a dispersion in an aqueous medium at ambient temperature.
As used herein the term "plasticizing agent refers to an organic compound which, when added to a high polymer, may increase the ease of processing the high polymer or increase the toughness and flexibility of the high polymer after processing. A plasticizing agent may be able to accomplish all of these.
As used herein the term "thin film" refers to a film having an averagethicknessoflessthanabout10 mils. Forexample,thethinfilm may have an average thickness of less than about 5 mils. More particularly, the thin film may have an average thickness of less than about 1 mil. Average thickness is determined by five (5) random measurements of the film and averaging the results.
As used herein the term "self sealing thin film" or "self sealable thTn film" refers to a thin film which, in the presence of water vapor, has ability to seal apertures having an area of less than about 625,000 square microns.
As used herein the term "aperture" refers to holes having an area of less than about 625,000 square microns. For example, an aperture may have an area of from about 10 to about 625,000 square microns.
More particularly, an aperture may have an area of from about 100 to ~7~
' :
about 235,000 square microns. Even more particularly, an aperture may have an area of from about 500 to about 10,000 square microns.
SUMMARY OF THE INVENTION
The present invention is directed toward a film material which, if apertured, has the ability, in the presence of water vapor or water, to self seal the apertures if they have an area of less than about 625,000 square microns. The material includes at least about 75 weight percent 10 of a water dispersible polymer; from about 0.5 to about 5 weight percent of a xerogellant and from about 7.5 to about 20 weight percent of aplasticizing agent.
In some embodiments the self sealing film material may include at Ieast about 81 weight percent of a water dispersible polymer; from 15 about 1 to about 4 weight percent of a xerogellant and from about 10 to about 15 weight percent of a plasticizing agent. For example, the self sealing film material may include at least about 83 weight percent of a water dispersible polymer; from about 2 to about 3 weight percent of a xerogellant and from about 11 to about 14 weight percent of a . .. ...
20 plasticizing agent. Moreparticularly,theself sealingfilm material may include at least about 84.5 weight percent of a water dispersible polymer; about 2.5 weight percent of a xerogellant and about 13 weight percent of a plasticizing agent.
.- -~ ,.
~ -~''.' .".'' ';
~717~
In some embodiments the water dispersible polymer may be selected from the group including high molecular weight amorphous polyesters having one or more ionic substituents attached thereto. In other embodiments the water dispersible polymer may be selected from 5 the group including elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof. In one embodiment the water dispersible polymer is an elastomeric emulsion which includes about 50% latex, about 50% water, less than about 0.01% acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01%
ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
In some embodiments the xerogellant may be selected from the group including sodium carboxymethyl cellulose, derivatives of sodium 15 carboxymethyl cellulose, poly(acrylic acid) salts, (ethylene oxide), acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate) and polyisobutylen~co-disodium maleate.
In some embodiments the plasticizing agent may be selected from the group including glycerin, sorbitol, glucidol, sucrose, ethylene glycol, 20 propylene glycol, diethylene glycol, polyethylene glycol, acid amides, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone.
In some embodiments the thin film ~ ial~i~ capable of self sealing apertures having an area of less than about 625,000 square microns in the presence of 75 percent relative humidity in about 30 seconds. For example, the thin film material may be capable of self sealing apértures having an area of less than about 235,000 square microns in the presence of 50 percent relative humidity in about 30 seconds. More particularly, the thin film material may be capable of self sealing apertures having an area of less than about 10,000 square microns in the presence of 50 percent relative humidity in about 15 seconds. -BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood with reference to the attached drawings in which:
, Figure 1 is a photomicrograph of an apertured film :
sample prepared as described in Example I and exposed to 100 percent steam as described in Example II; ~ -Figure 2 is a photomicrograph of the film sample of Figure 1 showing the closed aperture after 15 seconds `.
exposure to the steam;
' ', ', ., :. ' Figure 3 is a photomicrograph of an apertured film ~ ; - .
sample prepared as described in Example I and exposed . .
to 100 percent steam as described in Example III; and :
Figure 4 is a photomicrograph of the film sample of . :~
Figure 1 showing the closed aperture after 5 seconds exposure to the steam.
2~7~ 71 DETAILED DESCRIPTION OF THE INVENTION
The self sealing film material of the present invention is formed by placing the xerogellant, preferably in powder form, in an appropriately sized container and adding water so that the xerogellant is fully hydrated. While any material meeting the definition of a xerogellant may be utilized, exemplary xerogellants include sodium carboxymethyl cellulose, poly(acrylic acid) salts, radiation crosslinked poly(ethylene oxide), carboxymethyl cellulose, acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate) and polyisobutylene-co-disodium maleate. One xerogellant is a starch 7(a) 2~7~7~
grafted sodium polvacrylate which may be obtained from Hoechst CelaneseCorporation underthetrade mark SanwetlM5000P.
If the consistency of the xerogellant and water mixture is not that of a fluid, additional water is added until such is the case. This action 5 is only necessary with certain xerogellants. It is to the fluidized xerogellant that the water dispersible polymer and the plasticizing agent are added. The water dispersible polymer may be added to the hydrated xerogellant as an aqueous dispersion.
While any film forming water dispersible polymer may be utilized, 10 exemplary film forming water dispersible polymers include such polymers chosen from the group including high molecular weight , amorphous polyesters having one or more ionic substituents attached thereto. This type of polymer is available form the Eastman Chemical Co.ofKingsport,Tennessee,underthetrade mark EastmanAQD
15 In particular, Eastman AQ 55D and AQ 38D. Alternatively the water dispersible polymer may be selected from the group including elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof. Exemplary elastomeric emulsions may beobtained , , . .:
20 from the B.F. Goodrich Co., Specialty Polymers & Chemicals Division under the trade mark HyStretch~. HyStretch~ elastomeric emulsions typically are a blend of about 50% latex, about 50% water, less than about 0.01% acrylamide, less than about 1.0% ammonium 2 :~ ~ 7 ~ 7 ~
hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1%
formaldehyde and less than about 0.0025% N-methylolacrylamide.
While any suitable plasticizing agent may be utilized, exemplary plasticizing agents include glycerin, sorbitol, glucidol, sucrose, ethylene 5 glycol, propylene glycol, diethylene glycol, polyethylene glycol, acid amides, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone. One exemplary plasticizing agent is glycerin which may be obtained from Fischer Scientific of Fairtown, New Jersey, under the trade mark G-33-1.
After the three components have been thoroughly mixed, they are cast, in conventional manner, in a film forming mold. Thereafter the water is removed by natural evaporation which, if desired, may be assisted by low grade heating of the cast mixture.
Discounting the water which is evaporated away, the xerogellant, 15 the film forming waterdispersible polymer and the plasticizing agent are blended together in a conventional manner so that the final weight percentage of these components, after removal of the water by evaporation, is at least about 81 weight percent of the water dispersible polymer; from about 1 to about 4 weight percent of the xerogellant:
20 and from about 10 to about 15 weight percent of the plasticizing agent.
More particularly, the final weight percentages of these components of the material may range from at least about 83 weight percent of the water dispersible polymer; from about 2 to about 3 weight percent of ~07~
, .
the xerogellant; and from about 11 to about 14 weight percent of the plasticizing agent. Even more particularly, the final weight percentages of these components may range from at least about 84.5 weight percent of the water dispersible polymer; about 2.5 weight percent of 5 the xerogellant; and about 13 weight percent of the plasticizing agent.
Those of skill in the art will readily recognize that the self sealing thin film material may be formed by other methods. For example, the material may be formed by extrusion methods.
The invention will now be described with respect to certain specific 10 embodiments thereof.
EXAMPLE I
About 0.352 grams of Sanwet IM500P xerogellant was combined with a~out 300 milliliters of water in a 600 milliliter beaker. The solution was stirred gently and the xerogellant was allowed to hydrate for sixty (60) minutes. The xerogellant swelled and a clear gel formed in the beaker. After 60 minutes, the gel was poured into a Waring blender model no. 7011 and mixed at high speed for about one minute, 20 resulting in a "liquified"solution. This liquified solution was poured back into the 600 milliliter beaker and about 24.26 grams of a 28% solution (6.79 grams of polymer) of water dispersible polymer obtained under the trade mark AQ55D form the Eastman Chemical Co. was * Trade-mark 10 ~ ~ :
, ' ~, ~107~7~
-added. Also added at this time was 1.068 grams of glycerol, a plasticizing agent, obtained under the trade mark G 33-1 from the Fischer Scientific Corp.
The mixture was stirred by hand gently with a glass stir rod and 5 then stirred mechanically with a magnetic stir bar until thoroughly mixed. Once mixed thoroughly, the solution was poured into two (2) individual wax molds, both measuring 0.5 inches deep, 4.0 inches wide and 8.0 inches long. The molds were machined from blocks ot wax by the McKellco Corp. of Alpharetta, Georgia. The solutions were 10 dehydrated initially in a micro/convection oven at 180 degrees Fahrenheit for one hour in order to speed up the evaporation process.
The molds were then removed from the oven and the films they contained were dried over desiccant for four (4) days until dry. A film having a thickness of about eight (8) mils was obtained.
The dried films were gently removed form each of the wax blocks and cut into small circles (having a diameter of three(3) inches) for testing and evaluation of the film's self sealing capabilities.
. ~ .
EXPERIMENTAL TESTING OF SELF SEALING CAPABIUTY
Apertures were made in the three inch diameter film samples by ~;
mechanically punching them with 200 needles bundled together in a one (1) inch diameter circle. The needle bundle was placed on top of 7 ~
the film so that the center of the needle bundle was located generally at the center of the sample and the bundle was gently tapped wlth a hammer until the needles cleanly broke through the film leaving behind about 200 apertures per square inch having diameters of from about 150 to about 250 microns. The diameters of the apertures were measured using conventional photomicrography equipment. One aperture, measured to be about 190 microns was selected and marked for the self sealing experiment.
The apertured sample was then sandwiched between two (2) impervious films each having a one (1) inch diameter circular aperture cut in the center of them. This sandwich was then mounted in a water vapor transmission test cup having a diameter of about 2.5 inches and containing about 100 milliliters of water. The cup and its contents were placed in a controlled temperature/humidity oven a 100 degrees Fahrenheit and 50 percent relative humidity.
After 15 minutes, the sample film was removed from the oven and removed from the 'sandwich". The 190 micron aperture was now closed.
This example was repeated with a film of essentially pure AQ 55D
and the aperture did not close.
:,,~'.
,~
~7~
EXAMPLE ll Another of the apertured samples prepared as described in Example 1, was exposed to 100 percent steam. The steam was 5 provided by boiling water in aPyrex*dish on a hot plate. A 250 micron aperture was selected and photomicrographed for this experiment.
Figure 1 is this photomicrograph. After 15 seconds in the steam environment, the aperture had closed as indicated by the after"
photomicrograph, Figure 2.
EXAMPLE lll In an effort to determine how rapidly the aperture closed or "self-sealed", Example ll was repeated with the apertured film being removed 15 from the steam environment in five (5) seconds. This is as rapid as this taskcould be accomplished.
Figure 3 is the 'before photomicrograph of the aperture of i_xample lll. Upon removing the sample from the steam environment after five (5) seconds, the aperture had c!osed as indicated by the "after"
20 photomicrograph, Figure4.
For comparison purposes, this experimentwas repeatedwith afilm of essentially pure AQ 55D and the aperture did not close up.
.. ' ,,.. - . ,.
* Trade-mark 13 Xl~7~
While the invention has been described in detail with respect to specific preferred embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to and variations of the preferred 5 embodiments. Such alterations and variations are believed to fall within the scope and spirit of the invention and the appended claims.
~ -
Claims (20)
1. A water vapor responsive self sealing thin film comprising:
at least about 75 weight percent of a water dispersible polymer;
from about 0.5 to about 5 weight percent of a xerogellant; and from about 7.5 to about 20 weight percent of a plasticizing agent.
at least about 75 weight percent of a water dispersible polymer;
from about 0.5 to about 5 weight percent of a xerogellant; and from about 7.5 to about 20 weight percent of a plasticizing agent.
2. A water vapor responsive self sealing thin film comprising:
at least about 81 weight percent of a water dispersible polymer;
from about 1 to about 4 weight percent of a xerogellant; and from about 10 to about 15 weight percent of a plasticizing agent.
at least about 81 weight percent of a water dispersible polymer;
from about 1 to about 4 weight percent of a xerogellant; and from about 10 to about 15 weight percent of a plasticizing agent.
3. A water vapor responsive self sealing thin film comprising:
at least about 83 weight percent of a water dispersible polymer;
from about 2 to about 3 weight percent of a xerogellant; and from about 11 to about 14 weight percent of a plasticizing agent.
at least about 83 weight percent of a water dispersible polymer;
from about 2 to about 3 weight percent of a xerogellant; and from about 11 to about 14 weight percent of a plasticizing agent.
4. The self sealing film of claim 1, comprising:
about 84.5 weight percent of a water dispersible polymer;
about 2.5 weight percent of a xerogellant; and about 13 weight percent of a plasticizing agent.
about 84.5 weight percent of a water dispersible polymer;
about 2.5 weight percent of a xerogellant; and about 13 weight percent of a plasticizing agent.
5. The self sealing film of claim 1, wherein the water dispersible polymer is selected from the group consisting of high molecular weight amorphous polyesters having one or more ionic substituents attached thereto.
6. The film of claim 1, wherein the water dispersible polymer is selected from the group consisting of elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof.
7. The self sealing film of claim 1, wherein the elastomeric emulsion comprises about 50% latex, about 50% water, less than about 0.01%
acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
8. The self sealing film of claim 1, wherein the xerogellant is selected from the group consisting of sodium carboxymethyl cellulose, derivatives of sodium carboxymethyl cellulose, poly(acrylic acid) salts, poly(ethylene oxide), acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate), polyisobutylene-co-disodium maleate).
9. The self sealing film of claim 1, wherein the plasticizing agent is selected from the group consisting of glycerin, sorbitol, glucidol, sucrose, ethylene glycol, propylene glycol, diethylene glycol, polyethyleneglycol, acid amide, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone.
10. The self sealing film of claim 1, wherein the thin film material is capable of self sealing apertures having an area of less than about 625,000 square microns in the presence of no more than 75 percent relative humidity in less than about 30 seconds.
11. The self sealing film of claim 1, wherein the thin film material is capable of self sealing apertures having an area of less than about 235,000 square microns in the presence of no more than 50 percent relative humidity in less than about 30 seconds.
12. The self sealing film of claim 1, wherein the thin film material is capable of self sealing apertures having an area of less than about 10,000 square microns in the presence of no more than 50 percent relative humidity in less than about 15 seconds.
13. The self sealing film of claim 3, wherein the water dispersible polymer is selected from the group consisting of high molecular weight amorphous polyesters having one or more ionic substituents attached thereto.
14. The film of claim 3, wherein the water dispersible polymer is selected from the group consisting of elastomeric emulsions, acrylic polymers, polyoxides, vinyl polymers, cellulose derivatives, starch derivatives, polysaccahrides, proteins and copolymers thereof.
15. The self sealing film of claim 3, wherein the elastomeric emulsion comprises about 50% latex, about 50% water, less than about 0.01%
acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
acrylamide, less than about 1.0% ammonium hydroxide, less than about 0.01% ethyl acrylate, less than about 0.1% formaldehyde and less than about 0.0025% N-methylolacrylamide.
16. The self sealing film of claim 3, wherein the xerogellant is selected from the group consisting of sodium carboxymethyl cellulose, derivatives of sodium carboxymethyl cellulose, poly(acrylic acid) salts, poly(ethylene oxide), acrylonitrile-grafted starch, hydrolyzed polyacrylonitrile, poly(vinyl alcohol-sodium acrylate), polyisobutylene-co-disodium maleate).
17. The self sealing film of claim 3, wherein the plasticizing agent is selected from the group consisting of glycerin, sorbitol, glucidol, sucrose, ethylene glycol, propylene glycol, diethylene glycol, polyethyleneglycol, acid amide, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone.
18. The self sealing film of claim 3, wherein the thin film material is capable of self sealing apertures having an area of less than about 625,000 square microns in the presence of no more than 75 percent relative humidity in less than about 30 seconds.
19. The self sealing film of claim 3, wherein the thin film material is capable of self sealing apertures having an area of less than about 235,000 square microns in the presence of no more than 50 percent relative humidity in less than about 30 seconds.
20. The self sealing film of claim 3, wherein the thin film material is capable of self sealing apertures having an area of less than about 10,000 square microns in the presence of no more than 50 percent relative humidity in less than about 15 seconds.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US046,064 | 1993-04-12 | ||
| US08/046,064 US5580910A (en) | 1993-04-12 | 1993-04-12 | Self sealing film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2107171A1 true CA2107171A1 (en) | 1994-10-13 |
Family
ID=21941397
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002107171A Abandoned CA2107171A1 (en) | 1993-04-12 | 1993-09-28 | Self sealing film |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US5580910A (en) |
| EP (1) | EP0694051B1 (en) |
| JP (1) | JPH08509254A (en) |
| KR (1) | KR100312391B1 (en) |
| AU (1) | AU679057B2 (en) |
| CA (1) | CA2107171A1 (en) |
| DE (1) | DE69419251T2 (en) |
| FR (1) | FR2703998B1 (en) |
| WO (1) | WO1994024196A1 (en) |
| ZA (1) | ZA941889B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5955187A (en) * | 1995-06-06 | 1999-09-21 | Kimberly-Clark Worldwide, Inc. | Microporous film with liquid triggered barrier feature |
| BE1010328A3 (en) * | 1996-06-06 | 1998-06-02 | Solvay | Treatment method of flat product with a starch phase. |
| US6258308B1 (en) | 1996-07-31 | 2001-07-10 | Exxon Chemical Patents Inc. | Process for adjusting WVTR and other properties of a polyolefin film |
| EP0893113A1 (en) * | 1997-07-25 | 1999-01-27 | The Procter & Gamble Company | Absorbent articles having a liquid swellable breathable backsheet |
| EP1025152A1 (en) * | 1997-10-31 | 2000-08-09 | Monsanto Company | Plasticized polyhydroxyalkanoate compositions and methods for their use in the production of shaped polymeric articles |
| ATE249913T1 (en) | 1998-10-16 | 2003-10-15 | Exxonmobil Chem Patents Inc | METHOD FOR PRODUCING MICROPOROUS BREATHABLE POLYETHYLENE FILM |
| MXPA03002898A (en) * | 2000-10-13 | 2003-06-24 | Kimberly Clark Co | Self heat sealable packaging and a method for making same. |
| WO2008069711A1 (en) * | 2006-12-08 | 2008-06-12 | Sca Hygiene Products Ab | An absorbent article containing a breathable material layer |
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| US3365320A (en) * | 1965-05-17 | 1968-01-23 | Eureka Carlisle Company | Process of making an aqueous adhesive |
| US3526538A (en) * | 1968-09-23 | 1970-09-01 | Air Reduction | Nonwoven fabric product and the like and preparation thereof |
| US3554788A (en) * | 1968-10-09 | 1971-01-12 | Johnson & Johnson | Water dispersible nonwoven fabric |
| US3580253A (en) * | 1968-12-09 | 1971-05-25 | Kimberly Clark Co | Sanitary napkin and flushable wrapper therefor |
| GB1379660A (en) * | 1972-05-23 | 1975-01-08 | Johnson & Johnson | Nonwoven fabric and sanitary napkin comprising it |
| US3952347A (en) * | 1973-12-13 | 1976-04-27 | Personal Products Company | Biodegradable barrier film and absorbent pad utilizing same |
| US4200558A (en) * | 1973-12-24 | 1980-04-29 | Hoechst Aktiengesellschaft | Method of producing hydrophilic articles of water-insoluble polymers |
| US3890974A (en) * | 1974-06-18 | 1975-06-24 | Union Carbide Corp | Disposable absorbent article containing slitted hydrogel film |
| US4028290A (en) * | 1975-10-23 | 1977-06-07 | Hercules Incorporated | Highly absorbent modified polysaccharides |
| US4063995A (en) * | 1975-10-28 | 1977-12-20 | Scott Paper Company | Fibrous webs with improved bonder and creping adhesive |
| US4186233A (en) * | 1978-03-27 | 1980-01-29 | The Dow Chemical Company | Disposable composite insensitive to surface moisture but disintegratable in aqueous liquid |
| JPS5913213B2 (en) * | 1979-04-28 | 1984-03-28 | ゼンミ株式会社 | sanitary napkin |
| US4319956A (en) * | 1980-06-16 | 1982-03-16 | The Dexter Corporation | Nonwoven web material for medical towels and the like |
| US4454055A (en) * | 1980-08-25 | 1984-06-12 | National Starch And Chemical Corporation | Absorbent composition of matter, process for preparing same and article prepared therefrom |
| US4410571A (en) * | 1980-08-25 | 1983-10-18 | Johnson & Johnson | Absorbent products, process and compositions for immobilization of particulate absorbents |
| US4534767A (en) * | 1980-09-08 | 1985-08-13 | Hollister Incorporated | Protective sealing composition in molded form |
| US4578065A (en) * | 1981-06-10 | 1986-03-25 | Hollister Incorporated | Protective sealing composition in molded form |
| US4655840A (en) * | 1982-03-26 | 1987-04-07 | Warner-Lambert Company | Hydrophilic polymer compositions for injection molding |
| US4518721A (en) * | 1982-03-26 | 1985-05-21 | Richardson-Vicks Inc. | Hydrophilic denture adhesive |
| US4656062A (en) * | 1984-04-27 | 1987-04-07 | American Colloid Company | Self-healing bentonite sheet material composite article |
| ES2053566T5 (en) * | 1986-11-20 | 2000-06-01 | Ciba Spec Chem Water Treat Ltd | ABSORBENT PRODUCTS AND THEIR MANUFACTURE. |
| US5225489A (en) * | 1987-03-05 | 1993-07-06 | Allied-Signal Inc. | Composites of thermoplastic and thermoplastic polymers having therein short fibers derived from anisotropic polymers |
| JPS63304082A (en) * | 1987-06-03 | 1988-12-12 | Nippon Shokubai Kagaku Kogyo Co Ltd | Water stopping material and water stopping |
| US4913517A (en) * | 1988-07-11 | 1990-04-03 | American Telephone And Telegraph Company, At&T Bell Laboratories | Communication cable having water blocking strength members |
| US5013769A (en) * | 1988-08-22 | 1991-05-07 | Medipro Sciences Limited | Method of making a hydrogel-forming wound dressing or skin coating material |
| US5248720A (en) * | 1988-09-06 | 1993-09-28 | Ube Industries, Ltd. | Process for preparing a polyamide composite material |
| FR2640547B1 (en) * | 1988-12-20 | 1991-03-29 | Intissel Sa | COMPOSITE MATERIAL CAPABLE OF INFLATING IN THE PRESENCE OF WATER, SUPPORTS FOR USE IN THE PRODUCTION THEREOF AND USES THEREOF |
| JP2684217B2 (en) * | 1989-06-15 | 1997-12-03 | 三洋化成工業株式会社 | Moldable water absorbent resin composition |
| JPH0395211A (en) * | 1989-09-07 | 1991-04-19 | Sanyo Chem Ind Ltd | Moldable water-absorbing resin composition |
| US5056960A (en) * | 1989-12-28 | 1991-10-15 | Phillips Petroleum Company | Layered geosystem and method |
| GB2246373A (en) * | 1990-07-12 | 1992-01-29 | Arco Chem Tech | Nonwoven fabric |
| DE69127738T2 (en) * | 1990-10-26 | 1998-03-12 | Akzo Nobel Nv | Process for the production of aramid yarn coated with superabsorbent material |
| US5046730A (en) * | 1990-12-10 | 1991-09-10 | Bio Dynamics, Ltd. | Golf tee |
| JP3218647B2 (en) * | 1991-09-30 | 2001-10-15 | 日本ゼオン株式会社 | Adhesive plastisol composition and sealant between metal plates using the composition |
| JPH0657059A (en) * | 1992-08-13 | 1994-03-01 | Tonen Chem Corp | Water-absorptive resin composition |
| US5389068A (en) * | 1992-09-01 | 1995-02-14 | Kimberly-Clark Corporation | Tampon applicator |
-
1993
- 1993-04-12 US US08/046,064 patent/US5580910A/en not_active Expired - Fee Related
- 1993-09-28 CA CA002107171A patent/CA2107171A1/en not_active Abandoned
-
1994
- 1994-03-17 ZA ZA941889A patent/ZA941889B/en unknown
- 1994-03-30 FR FR9403752A patent/FR2703998B1/en not_active Expired - Fee Related
- 1994-04-11 EP EP94913398A patent/EP0694051B1/en not_active Expired - Lifetime
- 1994-04-11 AU AU65576/94A patent/AU679057B2/en not_active Ceased
- 1994-04-11 JP JP6523360A patent/JPH08509254A/en active Pending
- 1994-04-11 DE DE69419251T patent/DE69419251T2/en not_active Expired - Fee Related
- 1994-04-11 KR KR1019950704437A patent/KR100312391B1/en not_active IP Right Cessation
- 1994-04-11 WO PCT/US1994/003937 patent/WO1994024196A1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| AU679057B2 (en) | 1997-06-19 |
| WO1994024196A1 (en) | 1994-10-27 |
| JPH08509254A (en) | 1996-10-01 |
| US5580910A (en) | 1996-12-03 |
| FR2703998A1 (en) | 1994-10-21 |
| EP0694051B1 (en) | 1999-06-23 |
| KR960701928A (en) | 1996-03-28 |
| AU6557694A (en) | 1994-11-08 |
| KR100312391B1 (en) | 2001-12-28 |
| EP0694051A1 (en) | 1996-01-31 |
| FR2703998B1 (en) | 1995-09-29 |
| DE69419251T2 (en) | 2000-02-03 |
| ZA941889B (en) | 1994-10-18 |
| DE69419251D1 (en) | 1999-07-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |