WO1983003837A1 - Inactivated polyurethane and method for preparing it - Google Patents
Inactivated polyurethane and method for preparing it Download PDFInfo
- Publication number
- WO1983003837A1 WO1983003837A1 PCT/SE1983/000169 SE8300169W WO8303837A1 WO 1983003837 A1 WO1983003837 A1 WO 1983003837A1 SE 8300169 W SE8300169 W SE 8300169W WO 8303837 A1 WO8303837 A1 WO 8303837A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- polyurethane
- polymer
- inactivated
- groups
- hydroxyl group
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/26—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/08—Processes
-
- 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
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/04—Coating
- C08J7/0427—Coating with only one layer of a composition containing a polymer binder
-
- 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
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
-
- 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
- C08J2429/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2429/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2429/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
- Y10T428/31569—Next to natural rubber
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
- Y10T428/31573—Next to addition polymer of ethylenically unsaturated monomer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
- Y10T428/31573—Next to addition polymer of ethylenically unsaturated monomer
- Y10T428/31576—Ester monomer type [polyvinylacetate, etc.]
Definitions
- the present invention relates to an inactivated polyurethane and a method, for preparing it,
- Polyurethane is generally manufactured by a reaction between polyfunctional isocyanates and al- 5 cohols. The finished product then has a certain residual isocyanate content. It has long been known that isocya ⁇ nate molecules are toxic, this having restricted the use of polyurethane to fields where a certain isocyanate content has not been considered harmful. 10 An indication of the toxicity of isocyanate is that the hygienic limit value for its presence in the atmosphere (for instance in a workshop) is at present
- the object of the present invention therefore is to provide an inactivated polyurethane which can also be used in such products as will come into direct con ⁇ tact with the skin, suc as ear protectors or dressing materials, e.g. plaster.
- This object is achieved by coating polyurethane with a layer of a polymer which contains functional groups capable of reacting v/ith isocyanate. Free iso ⁇ cyanate groups leaving the polyurethane material will then be prevented not only mechanically from escaping out into the ambient atmosphere but will react with the alcohol groups in the polymer layer and be chemi ⁇ cally bound therein.
- the coating of the polyurethane can be carried out in various ways.
- the polyurethane can first be molded to the desired shape and thereafter be coated with a thin layer of a suitable polymer v/hich then reacts with isocyanate groups in the polyurethane.
- Another mode of producing the coating is first to apply a thin layer of a suitable polymer to the inner side of the mold in v/hich the polyurethane is to be shaped, and then form the polyurethane in the mold.
- Functional groups in the polymer will then react with isocyanate groups in the polyurethane, whereby the layer of polymer is chemically bonded to the polyurethane.
- a suitable hydroxyl group containing polymer is e.g. polyvinyl alcohol, but other hydroxyl group con ⁇ taining polymers mav also be used, such as partly hydrolyzed polyvinyl acetate or copolymers containing vinyl alcohol or hydrolyzed polyvinyl acetate, polymers prepared from vinyl and acrylate monomers containing hydroxyl groups, or hydroxyl group-terminated low mole ⁇ cular polyesters.
- Example v/hich is however not meant in any way to restrict the scope of the present invention.
- Tests were performed with sheetings of polyethy- lene, polyvinyl alcohol and polyvinyl alcohol treated with a catalyst (DABCO 33 LV) .
- the catalyst used is of the type employed in the production of polyurethane, and residues of spent catalyst are always present in the finished material. It was found that the amount of isocyanate that had penetrated through the sheeting of polyvinyl alcohol (not treated by catalyst) was about 50 times less than the a- ount that had penetrated through the polyethylene sheet ⁇ ing. The permeability of the catalyst-treated polyv ⁇ nyl alcohol sheeting to isocyanate molecules was still less. A lesser amount of 2,4-TDI than of 2,6-TDI initial ⁇ ly penetrates through the polyvinyl alcohol sheeting.
- 2,4-TDI is far more reactive than 2,6-TDI, this is indicatxve of a reaction taking place between the isocyanate molucules and the alcohol groups. The more reactive molecule is thus barred to a greater extent by the reactive protective film.
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Engineering & Computer Science (AREA)
- Hematology (AREA)
- Epidemiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Materials For Medical Uses (AREA)
- Polyurethanes Or Polyureas (AREA)
- Laminated Bodies (AREA)
Abstract
The polyurethane is inactivated by being coated with a layer of a polymer which contains e.g. hydroxyl groups. These hydroxyl groups react with free isocyanate molecules in the polyurethane material and a chemical bonding occurs which prevents noxious isocyanate molecules from coming into contact with the ambient atmosphere. The inactivated polyurethane will thereby be useful in products where it comes into direct contact with the skin or the mucous membranes.
Description
INACTIVATED POLYURETHANE AND A METHOD FOR PREPARING IT
* The present invention relates to an inactivated polyurethane and a method, for preparing it,
Polyurethane (PUR) is generally manufactured by a reaction between polyfunctional isocyanates and al- 5 cohols. The finished product then has a certain residual isocyanate content. It has long been known that isocya¬ nate molecules are toxic, this having restricted the use of polyurethane to fields where a certain isocyanate content has not been considered harmful. 10 An indication of the toxicity of isocyanate is that the hygienic limit value for its presence in the atmosphere (for instance in a workshop) is at present
2 (in Sweden) as low as 0.01 ppm [ml (gas)/m (air)].
However, there is no limit value for the residual con-
15 tent of isocyanate monomers..in completely cured poly¬ urethane material, which may be attributable to the fact that no suitable method of analysis for detecting so low contents of isocyanate molecules as here con¬ templated has been elaborated.
20 The commonest symptom of exposure to isocyanate are allergic troubles in the form of irritations of the mucous membranes and the skin. Since the residual isocyanate monomer content of completely cured poly¬ urethane is very low, it is possible nevertheless in
25 many instances to use polyurethane in cases where the human body comes into contact with the material, if an air gap can be provided between the polyurethane and the body. One example of this is the use as padding in mattresses which are covered with a fabric.
30 Considering the other properties of polyurethane, it would also serve well in other products, but its use has hitherto been hampered to a great extent by its noxiousness to the skin and the mucous membranes. The object of the present invention therefore is
to provide an inactivated polyurethane which can also be used in such products as will come into direct con¬ tact with the skin, suc as ear protectors or dressing materials, e.g. plaster. This object is achieved by coating polyurethane with a layer of a polymer which contains functional groups capable of reacting v/ith isocyanate. Free iso¬ cyanate groups leaving the polyurethane material will then be prevented not only mechanically from escaping out into the ambient atmosphere but will react with the alcohol groups in the polymer layer and be chemi¬ cally bound therein.
Examples of preferred functional groups which are capable of reacting with isocyanate are hydroxyl groups. The coating of the polyurethane can be carried out in various ways. Thus, the polyurethane can first be molded to the desired shape and thereafter be coated with a thin layer of a suitable polymer v/hich then reacts with isocyanate groups in the polyurethane. Another mode of producing the coating is first to apply a thin layer of a suitable polymer to the inner side of the mold in v/hich the polyurethane is to be shaped, and then form the polyurethane in the mold. Functional groups in the polymer will then react with isocyanate groups in the polyurethane, whereby the layer of polymer is chemically bonded to the polyurethane.
A suitable hydroxyl group containing polymer is e.g. polyvinyl alcohol, but other hydroxyl group con¬ taining polymers mav also be used, such as partly hydrolyzed polyvinyl acetate or copolymers containing vinyl alcohol or hydrolyzed polyvinyl acetate, polymers prepared from vinyl and acrylate monomers containing hydroxyl groups, or hydroxyl group-terminated low mole¬ cular polyesters. For a more detailed illustration of the invention, reference is now had to the following Example v/hich is however not meant in any way to restrict the scope of the present invention.
EXAMPLE
Since the isocyanate content of polyurethane is so low that it cannot be analyzed by conventional methods a model test has been conducted in order to illustrate the penetration of the isocyanate molecule through poly¬ vinyl alcohol.
A mixture of toluene-2,4-diisocyanate (2,4-TDI) and toluene-2,6-diisocyanate (2,6-TDI) , which are common starting materials for the preparation of polyurethane, was batched in a test tube over which the sheeting to be examined was stretched. Over the sheeting was placed a sealing flask having two taps. The polymer sheeting and the TDI were heated to 65-?70°C. 20 1 of air were blown for 20 min. through one tap of the flask and were collect ed at the other tap. The amount of isocyanate which had penetrated through the sheeting and been entrained by the current of air was determined by a gas chromatographi standard method.
Tests were performed with sheetings of polyethy- lene, polyvinyl alcohol and polyvinyl alcohol treated with a catalyst (DABCO 33 LV) . The catalyst used is of the type employed in the production of polyurethane, and residues of spent catalyst are always present in the finished material. It was found that the amount of isocyanate that had penetrated through the sheeting of polyvinyl alcohol (not treated by catalyst) was about 50 times less than the a- ount that had penetrated through the polyethylene sheet¬ ing. The permeability of the catalyst-treated polyvΛnyl alcohol sheeting to isocyanate molecules was still less. A lesser amount of 2,4-TDI than of 2,6-TDI initial¬ ly penetrates through the polyvinyl alcohol sheeting. Since 2,4-TDI is far more reactive than 2,6-TDI, this is indicatxve of a reaction taking place between the isocyanate molucules and the alcohol groups. The more reactive molecule is thus barred to a greater extent by the reactive protective film.
Claims
1. Inactivated polyurethane coated with a protec¬ tive layer, c h a r a c t e r i s e d in that it is coated with a layer of a hydroxyl group containing poly¬ mer the hydroxyl groups of which are capable of react- ing with free isocyanate groups in the polyurethane, said polymer comprising polyvinyl alcohol, partly hydro¬ lyzed polyvinyl acetate or a copolymer containing vinyl alcohol or hydrolyzed polyvinyl acetate, a polymer pre¬ pared from vinyl and acrylate monomers containing hy- droxyl groups, or a hydroxyl group-terminated low mole¬ cular polyester.
2. A method for preparing an inactivated polyure¬ thane, c h a r a c t e r i s e d by coating the poly¬ urethane with a protective layer of a hydroxyl group containing polymer the hydroxyl groups of which are capable of reacting v/ith free isocyanate groups in the polyurethane, said polymer comprising polyvinyl alcohol, partly hydrolyzed polyvinyl acetate or a copolymer con¬ taining vinyl alcohol or hydrolyzed polyvinyl acetate, a polymer prepared from vinyl and acrylate monomers containing hydroxyl groups, or a hydroxyl group-terminat¬ ed low molecular polyester.
3. Method as claimed in claim 2, c h a r a c ¬ t e r i s e d in that the coating is effected by coat- ing the polyurethane with the protective layer after molding the polyurethane to the desired shape.
4. Method as claimed in claim 2, c h a r a c ¬ t e r i s e d in that the coating is effected by apply- ing a layer of the polymer to the inner side of a mold in which the polyurethane is to be shaped, and there¬ after molding the polyurethane.
5. The use of the inactivated polyurethane as claim¬ ed in claim 1 in ear protectors or dressing materials.
OA-PI
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE8202776-4 | 1982-05-04 | ||
SE8202776A SE430697B (en) | 1982-05-04 | 1982-05-04 | INACTIVATED POLYURETHANE, SET TO PREPARE THIS AND USE IT |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1983003837A1 true WO1983003837A1 (en) | 1983-11-10 |
Family
ID=20346710
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SE1983/000169 WO1983003837A1 (en) | 1982-05-04 | 1983-04-28 | Inactivated polyurethane and method for preparing it |
Country Status (5)
Country | Link |
---|---|
US (1) | US4552817A (en) |
EP (1) | EP0108101A1 (en) |
ES (1) | ES8402603A1 (en) |
SE (1) | SE430697B (en) |
WO (1) | WO1983003837A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4808469A (en) * | 1985-05-09 | 1989-02-28 | Maurice Hiles | Energy absorbing polyurethane composite article |
KR20110045046A (en) * | 2008-08-11 | 2011-05-03 | 다우 글로벌 테크놀로지스 엘엘씨 | 1-part epoxy resin structural adhesives containing elastomer tougheners capped with phenol and hydroxy-terminated acrylate or hydroxy-terminated methacrylate |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2633743A1 (en) * | 1975-09-04 | 1977-03-10 | Goodyear Tire & Rubber | METHOD OF CONNECTING A POLYURETHANE TO A CURED RUBBER MATERIAL |
EP0006308A1 (en) * | 1978-06-08 | 1980-01-09 | Ici Americas Inc. | In-mould coating compositions containing functional group terminated liquid polymers and method of covering surface defects of a moulded thermoplastic article therewith |
SE421994B (en) * | 1973-04-24 | 1982-02-15 | Ici Ltd | LIQUID DENTIFICATION COMPOSITIONS |
DE3124982A1 (en) * | 1980-06-26 | 1982-02-25 | The General Tire & Rubber Co., 44329 Akron, Ohio | METHOD FOR COATING IN THE FORM AND COMPOSITION SUITABLE FOR THIS |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2806215A1 (en) * | 1978-02-14 | 1979-08-16 | Bayer Ag | PROCESS FOR THE PRODUCTION OF MOLDED FOAMS BASED ON POLYISOCYANATE |
JPS5525367A (en) * | 1978-08-11 | 1980-02-23 | Toyo Tire & Rubber Co Ltd | Method of fabricating polyurethane molded product with skin |
US4282285A (en) * | 1979-10-24 | 1981-08-04 | International Telephone & Telegraph Corporation | Process for preparing polyurethane molded part |
DE3014161A1 (en) * | 1980-04-12 | 1981-10-22 | Basf Ag, 6700 Ludwigshafen | METHOD FOR PRODUCING POLYURETHANE MOLDED BODIES |
US4487808A (en) * | 1982-04-22 | 1984-12-11 | Astra Meditec Aktiebolag | Medical article having a hydrophilic coating |
-
1982
- 1982-05-04 SE SE8202776A patent/SE430697B/en not_active IP Right Cessation
-
1983
- 1983-04-28 US US06/574,028 patent/US4552817A/en not_active Expired - Fee Related
- 1983-04-28 WO PCT/SE1983/000169 patent/WO1983003837A1/en unknown
- 1983-04-28 EP EP83901427A patent/EP0108101A1/en not_active Withdrawn
- 1983-05-03 ES ES522030A patent/ES8402603A1/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE421994B (en) * | 1973-04-24 | 1982-02-15 | Ici Ltd | LIQUID DENTIFICATION COMPOSITIONS |
DE2633743A1 (en) * | 1975-09-04 | 1977-03-10 | Goodyear Tire & Rubber | METHOD OF CONNECTING A POLYURETHANE TO A CURED RUBBER MATERIAL |
EP0006308A1 (en) * | 1978-06-08 | 1980-01-09 | Ici Americas Inc. | In-mould coating compositions containing functional group terminated liquid polymers and method of covering surface defects of a moulded thermoplastic article therewith |
DE3124982A1 (en) * | 1980-06-26 | 1982-02-25 | The General Tire & Rubber Co., 44329 Akron, Ohio | METHOD FOR COATING IN THE FORM AND COMPOSITION SUITABLE FOR THIS |
Also Published As
Publication number | Publication date |
---|---|
ES522030A0 (en) | 1984-02-01 |
US4552817A (en) | 1985-11-12 |
ES8402603A1 (en) | 1984-02-01 |
SE430697B (en) | 1983-12-05 |
SE8202776L (en) | 1983-11-05 |
EP0108101A1 (en) | 1984-05-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4920172A (en) | Hydrophilic polyurethane emulsions and materials produced therefrom | |
US5238732A (en) | Waterproof breathable polyurethane membranes and porous substrates protected therewith | |
FI116224B (en) | Process for the production of flexible foams | |
EP0231918B1 (en) | Polymeric materials having controlled physical properties and processes for obtaining these | |
WO1985005322A1 (en) | Moisture vapor permeable materials | |
JPS58108219A (en) | Manufacture of crosslinked hydrophilic foamed body | |
CA2216236A1 (en) | Polyurethane/polyurea compositions containing silicone for biosensor membranes | |
WO1994002526A1 (en) | Waterproof breathable polyurethane membranes and porous substrates protected therewith | |
US5014361A (en) | Polyurethane elastic glove having improved puncture and tear resistance | |
WO1994022934A1 (en) | Random block copolymers | |
EP0183790B1 (en) | Moisture vapor permeable materials containing segmented block multipolymer | |
US4381332A (en) | Adhesive and resulting nonwoven fabric | |
JP2000355619A (en) | Processible thermoplastic polyurethane molding material | |
EP0463835A2 (en) | Antioxidant containing hydrophilic urethane polymer, dry cleaning solvent-resistant, waterproof moisture-vapor permeable material containing the polymer, and method of making the same | |
EP0339435B1 (en) | Prepolymer composition, process for its production, and its use | |
WO1983003837A1 (en) | Inactivated polyurethane and method for preparing it | |
WO1989003860A1 (en) | Moisture sensitive elastomer compositions | |
GB1579412A (en) | Surface treatment of polyvinyl fluoride | |
AU686689B2 (en) | Hydrophilic polyurethane | |
EP1565506A1 (en) | Articles comprising aqueous dispersions using poly(urea/urethanes) | |
JPH0426303B2 (en) | ||
KR101054592B1 (en) | Articles treated with an aqueous dispersion of poly (urea / urethane) | |
US4676234A (en) | Moisture-hardenable bandaging materials | |
JPH0632863A (en) | Production of water absorbing cross-linked substance | |
KR101181218B1 (en) | Composition of Hydrophilic polyurethane foam and preparation method thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Designated state(s): DK FI JP NO US |
|
AL | Designated countries for regional patents |
Designated state(s): AT BE CH DE FR GB LU NL SE |