EP0027706A1 - Latex bound non-asbestos paper - Google Patents

Latex bound non-asbestos paper Download PDF

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Publication number
EP0027706A1
EP0027706A1 EP80303570A EP80303570A EP0027706A1 EP 0027706 A1 EP0027706 A1 EP 0027706A1 EP 80303570 A EP80303570 A EP 80303570A EP 80303570 A EP80303570 A EP 80303570A EP 0027706 A1 EP0027706 A1 EP 0027706A1
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EP
European Patent Office
Prior art keywords
fibres
wool
asbestos paper
vitreous
water
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.)
Withdrawn
Application number
EP80303570A
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German (de)
French (fr)
Inventor
Brian Hargreaves
Robert Allan Lancaster
Brian Healey
Alan Kenneth Cousens
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Turner and Newall Ltd
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Turner and Newall Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Turner and Newall Ltd filed Critical Turner and Newall Ltd
Publication of EP0027706A1 publication Critical patent/EP0027706A1/en
Withdrawn legal-status Critical Current

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Classifications

    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36Inorganic fibres or flakes
    • D21H13/38Inorganic fibres or flakes siliceous
    • D21H13/40Inorganic fibres or flakes siliceous vitreous, e.g. mineral wool, glass fibres
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20Macromolecular organic compounds
    • D21H17/33Synthetic macromolecular compounds
    • D21H17/34Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/35Polyalkenes, e.g. polystyrene
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20Macromolecular organic compounds
    • D21H17/33Synthetic macromolecular compounds
    • D21H17/34Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/37Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20Macromolecular organic compounds
    • D21H17/33Synthetic macromolecular compounds
    • D21H17/46Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/47Condensation polymers of aldehydes or ketones
    • D21H17/49Condensation polymers of aldehydes or ketones with compounds containing hydrogen bound to nitrogen
    • D21H17/51Triazines, e.g. melamine
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63Inorganic compounds
    • D21H17/67Water-insoluble compounds, e.g. fillers, pigments
    • D21H17/68Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays

Definitions

  • This invention relates to latex-bound paper, and provides non-asbestos alternatives to latex-bound asbestos papers.
  • Latex-bound papers based on asbestos fibres are employed in the manufacture of gaskets and seals for use in motor vehicles, where they must be resistant to water, anti-freeze, oil a.nd petrol and withstand fairly high temperatures, e.g. 150°C. They are also used in the chemical industry in making seals resistant to chemical attack. They are commonly made in the form of flexible sheet of thickness 0.1-1.5mm on conventional paper-making machines such as the Fourdrinier. In the process an aqueous slurry of the ingredients which are to compose the product is progressively dewatered as a layer on a water-permeable conveyor (usually of wire mesh), the dewatered layer being subsequently compressed and dried.
  • a water-permeable conveyor usually of wire mesh
  • non-asbestos paper comprises vitreous fibres derived from wool-form material, organic web-forming fibres, unfired ball clay and water-insoluble non-fibrous particulate inorganic filler, the whole being bound toqether by a cured nitrile rubber; said paper being made by dewatering as a layer on a water-permeable conveyor an aqueous slurry whose solids content comprises by weight:- and compressing and drying the layer of dewatered slurry.
  • the vitreous'wool-form fibre employed is preferably glass wool, mineral wool or ceramic fibre wool. If glass wool is used it is preferably employed in a form which has been treated with a silane coupling agent (e.g. gamma-aminopropyltriethoxysilane).
  • silane coupling agent e.g. gamma-aminopropyltriethoxysilane
  • the function of the organic web-forming fibres is primarily to enable the paper to be formed on conventional paper-making machinery, but additionally those fibres impart strength to the total matrix of the finished paper, just as the vitreous fibres derived from wool-form material (the primary reinforcement) do.
  • the organic web-forming fibres are preferably cellulose fibres, but may alternatively be polyethylene or' polypropylene fibres of the kind commercially available under the name PULPEX.
  • the function of the ball clay is to impart handlability to the paper sheet during manufacture.
  • the wate-r-insoluble non-fibrous particulate inorganic filler may be of the kind conventionally used in paper manufacture, for example calcium carbonate, talc, calcium sulphate, kaolin, titanium dioxide, magnesium silicate, or barytes (barium sulphate).
  • barytes which both densifies and improves the oil resistance of the paper, is particularly preferred.
  • the nitrile rubber, which bonds all the fibrous and non-fibrous particles of the paper together is introduced during manufacture as a latex, together with a vulcanising (curing) agent of the usual kind.
  • the paper may contain small amounts (e.g. 0.5-2.5% by weight) of fibres other than the vitreous fibres derived from wool-form material and the web-forming fibres.
  • Such other fibres may for instance be low modulus carbon fibres or water-dispersible E-glass fibres. Such fibres improve green strength of the paper during manufacture; additionally the low modulus carbon fibres impart lubricity to the finished paper.
  • Low modulus here means a Young's modulus in tension below 125GPa.
  • a melamine-formaldehyde resin suitably at about 1% by weight, can be included in the slurry that is dewatered, in order to promote bonding between the various fibres and the nitrile rubber.
  • a small quantity (0.002-0.01% by dry weight of total solids in the slurry) of a flocculating agent of the kind (e.g. a polyacrylamide polyelectrolyte) ordinarily used in paper making can be included in order to facilitate sheet formation and subsequent dewatering.
  • a flocculating agent of the kind e.g. a polyacrylamide polyelectrolyte
  • the stocks (slurries) prepared as in A. above from various formulations as set out in tablesl-3 following were made into flexible sheet material in an entirely conventional way on a Fourdrinier flat wire paper machine, such as is described in Chapters 10 and 11 of "Paper and Board Manufacture” by Julius Grant, James H. young, and Barry G. Watson (Publishers; Technical Division, The British Paper and Board Industry Federation, London, 1978).
  • the slurry. is progressively dewatered as it travels on the water permeable conveyor of the machine, and the dewatered material is consolidated by pressing between rollers, and then dried to low moisture content (suitably 2% by weight).
  • Paper was passed at room temperature between two smooth-faced steel rolls the gap between which was adjustable to control the density of the paper. Two such passes were made on the papers whose properties are reported in Table I.
  • the hot calendering referred to in Table I was carried out as for cold calendering but with the difference that the steel rolls were heated to about a temperature of 145°C. Again, two such passes were made on the papers whose properties are reported in Table I.
  • the purpose of hot calendering as opposed to cold calendering on latex-bound papers is to cause some flow of the latex, thus producing greater consolidation and a higher density.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Paper (AREA)
  • Sealing Material Composition (AREA)

Abstract

Non-asbestos paper alternatives to latex-bound asbestos papers comprise vitreous fibres derived from wool-form material, organic web-forming fibres, unfired ball clay and water-insoluble non-fibrous particulate inorganic filler, the whole being bound together by a cured nitrile rubber; said paper being made by dewatering as a layer on a water-permeable conveyor an aqueous slurry whose solids content comprises by weight vitreous wool-form material 20-40%, organic web-forming fibres 5-15%, ball clay 5-20%, nitrile rubber 10-20%, and inorganic non-fibrous filler 5-50%, and compressing and drying the layer of dewatered slurry.

Description

  • This invention relates to latex-bound paper, and provides non-asbestos alternatives to latex-bound asbestos papers.
  • Latex-bound papers based on asbestos fibres are employed in the manufacture of gaskets and seals for use in motor vehicles, where they must be resistant to water, anti-freeze, oil a.nd petrol and withstand fairly high temperatures, e.g. 150°C. They are also used in the chemical industry in making seals resistant to chemical attack. They are commonly made in the form of flexible sheet of thickness 0.1-1.5mm on conventional paper-making machines such as the Fourdrinier. In the process an aqueous slurry of the ingredients which are to compose the product is progressively dewatered as a layer on a water-permeable conveyor (usually of wire mesh), the dewatered layer being subsequently compressed and dried.
  • According to the invention, non-asbestos paper comprises vitreous fibres derived from wool-form material, organic web-forming fibres, unfired ball clay and water-insoluble non-fibrous particulate inorganic filler, the whole being bound toqether by a cured nitrile rubber; said paper being made by dewatering as a layer on a water-permeable conveyor an aqueous slurry whose solids content comprises by weight:-
    Figure imgb0001
    and compressing and drying the layer of dewatered slurry.
  • The vitreous'wool-form fibre employed is preferably glass wool, mineral wool or ceramic fibre wool. If glass wool is used it is preferably employed in a form which has been treated with a silane coupling agent (e.g. gamma-aminopropyltriethoxysilane).
  • The function of the organic web-forming fibres is primarily to enable the paper to be formed on conventional paper-making machinery, but additionally those fibres impart strength to the total matrix of the finished paper, just as the vitreous fibres derived from wool-form material (the primary reinforcement) do. The organic web-forming fibres are preferably cellulose fibres, but may alternatively be polyethylene or' polypropylene fibres of the kind commercially available under the name PULPEX.
  • The function of the ball clay is to impart handlability to the paper sheet during manufacture. To improve the drainage properties of the ball-clay-containing slurry, it is preferable to include a small proportion of bentonite (up to about 5% by weight of total solids) in the slurry.
  • The wate-r-insoluble non-fibrous particulate inorganic filler may be of the kind conventionally used in paper manufacture, for example calcium carbonate, talc, calcium sulphate, kaolin, titanium dioxide, magnesium silicate, or barytes (barium sulphate). The use of barytes, which both densifies and improves the oil resistance of the paper, is particularly preferred.
  • The nitrile rubber, which bonds all the fibrous and non-fibrous particles of the paper together is introduced during manufacture as a latex, together with a vulcanising (curing) agent of the usual kind.
  • The paper may contain small amounts (e.g. 0.5-2.5% by weight) of fibres other than the vitreous fibres derived from wool-form material and the web-forming fibres. Such other fibres may for instance be low modulus carbon fibres or water-dispersible E-glass fibres. Such fibres improve green strength of the paper during manufacture; additionally the low modulus carbon fibres impart lubricity to the finished paper. ("Low modulus" here means a Young's modulus in tension below 125GPa.)
  • A melamine-formaldehyde resin, suitably at about 1% by weight, can be included in the slurry that is dewatered, in order to promote bonding between the various fibres and the nitrile rubber. A small quantity (0.002-0.01% by dry weight of total solids in the slurry) of a flocculating agent of the kind (e.g. a polyacrylamide polyelectrolyte) ordinarily used in paper making can be included in order to facilitate sheet formation and subsequent dewatering. The invention is further illustrated by the following Example.
  • Example A. Preparation of Stock
    • (i) Lapponia pulp (bleached softwood sulphate pulp) in sheet form was made into an aqueous slurry of solids content about 3% by weight and treated in a disc refiner until its freeness reached the desired value (measured in degrees Schopper Riegler, °SR).
    • ii The other ingredients for incorporation in the slurry to be dewatered were added to enough water in a beater to bring the total solids content of the mix to about 5% by weight. The order of addition of the materials to the beater was:-
      • a. Wood pulp at desired freeness with 182 litres of water at 40-45°C.
      • b.. Ball clay (passing sieve of aperture 5pm), and bentonite and barytes (both passing sieve of aperture 0.15mm).
      • c. Mineral wool (fibre length 0.25-5mm; and free from 'shot' i.e. granular vitreous material); and E-glass fibre (borosilicate glass containing less than 1% of alkali calculated as Ha2O; 12mm fibre length) or carbon fibre (modulus in tension, 25 GPa; fibre length 12mm).
      • d. Papermakers' alum to reduce pH to 4.
      • e. Melamine-formaldehyde resin ('MF resin')
      • f. Sodium hydroxide to raise pH to 7-8.
      • g. Conventional vulcanising agent dispersion (active ingredients sulphur, zinc oxide and zinc dithiocarbamate) diluted with an equal volume of water.
      • h. Conventional wax emulsion (function; to improve wate.r resistance of the finished paper) diluted with an equal volume of water.
      • i. Conventional nitrile rubber latex (aqueous acrylonitrile- butadiene copolymer; butadiene content of copolymer, 55%; particle size O.Ipm; 40% solids content) diluted with 10 times its volume of water.
      • j. Alum to reduce pH to 4.5. NOTE: Where the wood pulp employed was of high °SR, the pulp was added after the final alum addition.
    • iii The slurry resulting from (ii) was diluted to a solids content of 1-3% by weight, and flocculating agent was added to it. immediately before passage to the paper making machine.
    B. Preparation of Paper
  • The stocks (slurries) prepared as in A. above from various formulations as set out in tablesl-3 following were made into flexible sheet material in an entirely conventional way on a Fourdrinier flat wire paper machine, such as is described in Chapters 10 and 11 of "Paper and Board Manufacture" by Julius Grant, James H. young, and Barry G. Watson (Publishers; Technical Division, The British Paper and Board Industry Federation, London, 1978). The slurry.is progressively dewatered as it travels on the water permeable conveyor of the machine, and the dewatered material is consolidated by pressing between rollers, and then dried to low moisture content (suitably 2% by weight).
  • The properties of the paper produced are shown in the Tables.
  • The cold calendering referred to in Table I was carried out as follows:-
  • Paper was passed at room temperature between two smooth-faced steel rolls the gap between which was adjustable to control the density of the paper. Two such passes were made on the papers whose properties are reported in Table I. The hot calendering referred to in Table I was carried out as for cold calendering but with the difference that the steel rolls were heated to about a temperature of 145°C. Again, two such passes were made on the papers whose properties are reported in Table I. The purpose of hot calendering as opposed to cold calendering on latex-bound papers is to cause some flow of the latex, thus producing greater consolidation and a higher density.
  • The papers all passed a standard test of flexibility. To pass this, a specimen of the paper (50mm x 230mm, with the 230mm side parallel to the grain) should show no evidence of breaking when bent through 180° around a mandrel of 50mm diameter, with use of just enough force to keep the specimen in contact with the mandrel.
  • Figure imgb0002
    Figure imgb0003
    Figure imgb0004

Claims (7)

1. Non-asbestos paper comprising vitreous fibres derived from wool-form material, organic web-forming fibres, unfired ball clay and water-insoluble non-fibrous particulate inorganic filler, the whole being bound together by a cured nitrile rubber; said paper being made by dewatering as a layer on a water-permeable conveyor an aqueous slurry whose solids content comprises by weight
vitreous wool-form material 20-40%
organic web-forming fibres 5-15%
ball clay 5-20%
nitrile ruber 10-20%
inorganic non-fibrous filler 5-50%

and compressing and drying the layer of dewatered slurry.
2. Non-asbestos paper according to claim 1, in which said vitreous wool-form material is mineral wool.
3. Non-asbestos paper according to claim 1, in which said vitreous wool-form material is glass wool.
4. Non-asbestos paper according to any one of claims 1 to 3, in which said organic web-forming fibres are cellulose fibres.
5. Non-asbestos paper according to any one of claims 1 to 4, in which the inorganic non-fibrous filler is barytes.
6. Non-asbestos paper according to any one of claims 1 to 5, which additionally contains carbon fibre of modulus below 125GPa or water-dispersible E glass fibres, said additional fibres being present in an amount of 0.5-2.5% by weight.
7.. Non-asbestos paper according to any preceding claim, made by dewatering a slurry which additionally contains bentonite up to 5% by weight of slurry solids
EP80303570A 1979-10-19 1980-10-09 Latex bound non-asbestos paper Withdrawn EP0027706A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB7936393 1979-10-19
GB7936393 1979-10-19

Publications (1)

Publication Number Publication Date
EP0027706A1 true EP0027706A1 (en) 1981-04-29

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ID=10508647

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Application Number Title Priority Date Filing Date
EP80303570A Withdrawn EP0027706A1 (en) 1979-10-19 1980-10-09 Latex bound non-asbestos paper

Country Status (4)

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EP (1) EP0027706A1 (en)
JP (1) JPS5668198A (en)
BR (1) BR8006648A (en)
ES (1) ES496022A0 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0104317A1 (en) * 1982-08-30 1984-04-04 Goetze Ag Flat soft material sealing product, in particular for the production of highly resistant flat seals
EP0112010A1 (en) * 1982-11-20 1984-06-27 T&N Materials Research Limited Flexible sheet material
FR2545115A1 (en) * 1983-04-27 1984-11-02 T & N Materials Res Ltd FLEXIBLE SHEET WITHOUT ASBESTOS AND JOINT CONSISTING OF SUCH A SHEET
FR2553121A1 (en) * 1983-10-06 1985-04-12 Arjomari Prioux PAPER SHEET, ITS PREPARATION METHOD AND ITS APPLICATIONS IN PARTICULAR AS A PRODUCT FOR SUBSTITUTING IMPREGNATED GLASS SAILS

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2130263B (en) * 1982-11-12 1985-10-02 T & N Materials Res Ltd Non-asbestos sheet material
JPS62164784A (en) * 1986-01-16 1987-07-21 Nippon Reinz Co Ltd Composition for joint sheet
WO2022230536A1 (en) * 2021-04-28 2022-11-03 阿波製紙株式会社 Inorganic-fiber sheet and production method therefor

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2773763A (en) * 1954-04-22 1956-12-11 Armstrong Cork Co Mineral fiber product containing hydrated virgin kraft pulp and method of producing the same
GB818652A (en) * 1956-04-23 1959-08-19 Armstrong Cork Co Manufacture of paper or the like
GB1107413A (en) * 1964-01-16 1968-03-27 United States Gypsum Co Water-felted mineral wool building insulation product
GB2001371A (en) * 1977-07-08 1979-01-31 Redco Sa Composition of a material based on mineral fibres

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2773763A (en) * 1954-04-22 1956-12-11 Armstrong Cork Co Mineral fiber product containing hydrated virgin kraft pulp and method of producing the same
GB818652A (en) * 1956-04-23 1959-08-19 Armstrong Cork Co Manufacture of paper or the like
GB1107413A (en) * 1964-01-16 1968-03-27 United States Gypsum Co Water-felted mineral wool building insulation product
GB2001371A (en) * 1977-07-08 1979-01-31 Redco Sa Composition of a material based on mineral fibres

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0104317A1 (en) * 1982-08-30 1984-04-04 Goetze Ag Flat soft material sealing product, in particular for the production of highly resistant flat seals
US4748075A (en) * 1982-08-30 1988-05-31 Goetze Ag Flat sealing material made of a soft substance, particularly for the production of gaskets that are to be subjected to high stresses
EP0112010A1 (en) * 1982-11-20 1984-06-27 T&N Materials Research Limited Flexible sheet material
FR2545115A1 (en) * 1983-04-27 1984-11-02 T & N Materials Res Ltd FLEXIBLE SHEET WITHOUT ASBESTOS AND JOINT CONSISTING OF SUCH A SHEET
FR2553121A1 (en) * 1983-10-06 1985-04-12 Arjomari Prioux PAPER SHEET, ITS PREPARATION METHOD AND ITS APPLICATIONS IN PARTICULAR AS A PRODUCT FOR SUBSTITUTING IMPREGNATED GLASS SAILS
EP0145522A1 (en) * 1983-10-06 1985-06-19 Arjomari-Prioux S.A. Paper sheet, process for producing it, and its applications in particular as a substitute for impregnated glass fibre mats

Also Published As

Publication number Publication date
ES8107350A1 (en) 1981-10-01
JPS5668198A (en) 1981-06-08
ES496022A0 (en) 1981-10-01
BR8006648A (en) 1981-04-22

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Inventor name: LANCASTER, ROBERT ALLAN