WO1992009744A1 - Non-asbestos flexible sheet material - Google Patents

Non-asbestos flexible sheet material Download PDF

Info

Publication number
WO1992009744A1
WO1992009744A1 PCT/GB1991/002061 GB9102061W WO9209744A1 WO 1992009744 A1 WO1992009744 A1 WO 1992009744A1 GB 9102061 W GB9102061 W GB 9102061W WO 9209744 A1 WO9209744 A1 WO 9209744A1
Authority
WO
WIPO (PCT)
Prior art keywords
clay
slurry
kaolinitic
dry weight
sheet material
Prior art date
Application number
PCT/GB1991/002061
Other languages
French (fr)
Inventor
David Geoffrey Hall
Antony Latkowski
Original Assignee
T&N Technology Limited
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 T&N Technology Limited filed Critical T&N Technology Limited
Publication of WO1992009744A1 publication Critical patent/WO1992009744A1/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00Materials not provided for elsewhere
    • C09K3/10Materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K3/1025Materials in mouldable or extrudable form for sealing or packing joints or covers characterised by non-chemical features of one or more of its constituents
    • C09K3/1028Fibres
    • 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
    • D21H13/10Organic non-cellulose fibres
    • D21H13/20Organic non-cellulose fibres from macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H13/26Polyamides; Polyimides
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16JPISTONS; CYLINDERS; SEALINGS
    • F16J15/00Sealings
    • F16J15/02Sealings between relatively-stationary surfaces
    • F16J15/06Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces
    • F16J15/10Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing
    • F16J15/12Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing with metal reinforcement or covering
    • F16J15/121Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing with metal reinforcement or covering with metal reinforcement
    • F16J15/122Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with non-metallic packing with metal reinforcement or covering with metal reinforcement generally parallel to the surfaces
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/02Inorganic compounds
    • C09K2200/0204Elements
    • C09K2200/0208Carbon
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/02Inorganic compounds
    • C09K2200/0239Oxides, hydroxides, carbonates
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/02Inorganic compounds
    • C09K2200/0243Silica-rich compounds, e.g. silicates, cement, glass
    • C09K2200/0252Clays
    • C09K2200/026Kaolin
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/02Inorganic compounds
    • C09K2200/0278Fibres
    • C09K2200/0291Glass fibres
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/06Macromolecular organic compounds, e.g. prepolymers
    • C09K2200/0607Rubber or rubber derivatives
    • C09K2200/0612Butadiene-acrylonitrile rubber
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2200/00Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
    • C09K2200/06Macromolecular organic compounds, e.g. prepolymers
    • C09K2200/0692Fibres
    • C09K2200/0695Polyamide fibres

Definitions

  • This invention relates to non-asbestos flexible sheet material suitable for use in gaskets for the cylinder head of an internal combustion engine.
  • GB 2 138 854 A and GB 2 138 855 A methods of making such sheet by a paper-making process: that is to say, by dewatering a layer of aqueous slurry and compressing and drying the de atered layer.
  • the aqueous slurry employed includes among its essential ingredients ball clay (a kaolinitic clay of high plasticity) as the paper matrix; cellulose fibres to assist the formation of a web on the water-permeable conveyor of the paper-making machine; fibrillated poly(aromatic amide) fibres as reinforcement; and polymer binder.
  • ball clay a kaolinitic clay of high plasticity
  • fibrillated poly(aromatic amide) fibres as reinforcement
  • polymer binder polymer binder
  • cellulose fibres in their capacity to confer strength at the high temperature (280- 300 deg C) at which the finished gasket has to operate.
  • the present invention modifies the above procedures with the object of obtaining gasket sheet material of better performance at high temperature, and in particular better able to retain an applied load, as when bolt-clamped between the engine block and cylinder head.
  • the aqueous slurry employed is substantially free from cellulose and contains the following ingredients in the following proportions by dry weight: kaolinitic clay 65-90% organic fibres consisting essentially of fibrillated poly(aromatic amide) fibres 5-15% polymeric binder 4-10%
  • said kaolinitic clay comprising both china clay and ball clay.
  • the ball clay is employed in the unfired state.
  • the china clay is preferably calcined china clay. Mixtures of ball clay and china clay may be used in which either of them predominates. In working examples 1 and 3 later, ball clay predominates; in example 2, it forms only a minor proportion of a mixture in which calcined china clay predominates. From the examples, it will be apparent that by varying the weight proportion of ball clay to china clay a range of properties (eg of tensile strength, compression and stress relaxation) can be optimised to suit particular applications.
  • the proportion of ball clay : china clay is in the range 20 : 1 - 1 : 20, particularly 15 : 1 - 1 : 15, and especially 5 : 1 - 1 : 5.
  • the kaolinitic clay forms not less than 75% by dry weight of the aqueous slurry.
  • a dark (and preferably black) pigment may be included in the slurry, suitably in an amount of 1-10% by dry weight.
  • black iron oxide may be included in the slurry, suitably in an amount of 1-10% by dry weight.
  • the slurry may include a proportion, suitably 1-10% by dry weight, of mineral wool in order to improve drainage of water from the web on the conveyor of the paper-making machine.
  • the polymeric binder employed is preferably an elastomer, which may be natural rubber but is preferably synthetic, for example an acrylonitrile-butadiene copolymer.
  • the elastomer is conveniently included in the slurry in the form of a latex.
  • a cross-linking agent may optionally be incorporated, along with antioxidant.
  • the fibrillated poly(aromatic amide) fibres provide essentially the sole organic web-forming fibres in the process, and these are suitably employed at a freeness of 30-70 degrees Schopper Riegler.
  • the fibres also provide reinforcement, both during "wet” stages of the paper- making process and during processing of the paper product into gaskets. Their reinforcing capacity for the kaolinitic clay matrix is particularly well retained at the high temperatures (280-300 degrees C) prevailing during IC engine operation.
  • Kevlar (registered trade mark) pulp is very suitably used.
  • the fibrillated poly(aromatic amide) or "aramid" fibres are used in an amount of 5-12% by dry weight of the aqueous paper-making slurry.
  • gaskets can be made by entirely conventional means, as by lamination onto each side of a metal sheet (plain, perforated, tanged or other); blanking of the laminate into the desired shape with appropriately spaced combustion chamber and other apertures; insertion of eyelets around the chamber apertures; impregnation with a silicone or other polymer to improve resistance to oil and aqueous anti-freeze solution; and coating of the surface to facilitate release from the cylinder head when the head is removed from the cylinder block.
  • a metal sheet plain, perforated, tanged or other
  • blanking of the laminate into the desired shape with appropriately spaced combustion chamber and other apertures insertion of eyelets around the chamber apertures
  • impregnation with a silicone or other polymer to improve resistance to oil and aqueous anti-freeze solution
  • coating of the surface to facilitate release from the cylinder head when the head is removed from the cylinder block.
  • the density of the sheet material product will ordinarily be in the range 700-1500 kg/m 3 .
  • a paper was prepared from an aqueous slurry having the following composition
  • the slurry of A above was made into flexible sheet material using a conventional Fourdrinier flat wire paper machine.
  • Conventional polyacrylamide flocculating agent and anti-foaming agent were added to assist processing.
  • the paper was then densified by use of a 2-bowl calender to produce flexible sheet material having the following properties
  • non- asbestos paper was made from a slurry whose composition was
  • the calcined china clay, ball clay and black iron oxide were mixed before addition to the diluted pulp, and no pH adjustment was made prior to addition of the nitrile rubber latex.
  • the calcined china clay had a specific surface area (BET) of 12m 2 /g, particle size 90% ⁇ 10 ⁇ , 50% ⁇ 2 p.
  • the resulting flexible sheet material had the following properties
  • Gaskets suitable for use on the cylinder heads of automobile engines were produced from the material by the conventional steps: (i) Lamination of the paper onto each side of plain steel core (ii) Blanking of the required gasket shape (iii) Insertion of steel eyelets into the combustion chamber bore holes of the gasket ( iv) Impregnation of the gasket with a silicone (v) Surface-coating with a release agent
  • a non- asbestos paper of improved properties can be made from a slurry of the following composition:

Abstract

Non-asbestos flexible sheet material suitable for use in gaskets for the cylinder head of an internal combustion engine is made by a paper-making process in which the aqueous slurry employed is substantially free from cellulose and contains the following ingredients in the following proportions by dry weight: kaolinitic clay comprising both ball clay and china clay 65-90 %, organic fibres consisting essentially of fibrillated poly(aromatic amide) fibres 5-15 %, polymeric binder, e.g. nitrile rubber 4-10 %.

Description

Non-asbestos flexible sheet material
This invention relates to non-asbestos flexible sheet material suitable for use in gaskets for the cylinder head of an internal combustion engine.
There are described in GB 2 138 854 A and GB 2 138 855 A methods of making such sheet by a paper-making process: that is to say, by dewatering a layer of aqueous slurry and compressing and drying the de atered layer. In both procedures the aqueous slurry employed includes among its essential ingredients ball clay (a kaolinitic clay of high plasticity) as the paper matrix; cellulose fibres to assist the formation of a web on the water-permeable conveyor of the paper-making machine; fibrillated poly(aromatic amide) fibres as reinforcement; and polymer binder. Of the fibrillated fibres of pol (aromatic amide) or "aramid", the cited prior publications state that they assist formation of a web, but not so effectively as the cellulose fibres; they are, however, much better than _
cellulose fibres in their capacity to confer strength at the high temperature (280- 300 deg C) at which the finished gasket has to operate.
The present invention modifies the above procedures with the object of obtaining gasket sheet material of better performance at high temperature, and in particular better able to retain an applied load, as when bolt-clamped between the engine block and cylinder head.
We have now found that this object can be achieved, with¬ out significantly adverse effect on other desirable proper¬ ties of the gasket paper produced, by omitting cellulose fibres from the aqueous slurry submitted to dewatering, by using a kaolinitic clay mixture, and by keeping the ingred¬ ients within certain limits by dry weight of the slurry.
According to the invention, in a method of making non-asbestos flexible sheet material suitable for use in gaskets for the cylinder head of an internal combustion engine, by dewatering a layer of aqueous slurry and compressing and drying the dewatered layer, the aqueous slurry employed is substantially free from cellulose and contains the following ingredients in the following proportions by dry weight: kaolinitic clay 65-90% organic fibres consisting essentially of fibrillated poly(aromatic amide) fibres 5-15% polymeric binder 4-10%
said kaolinitic clay comprising both china clay and ball clay.
The ball clay is employed in the unfired state. The china clay is preferably calcined china clay. Mixtures of ball clay and china clay may be used in which either of them predominates. In working examples 1 and 3 later, ball clay predominates; in example 2, it forms only a minor proportion of a mixture in which calcined china clay predominates. From the examples, it will be apparent that by varying the weight proportion of ball clay to china clay a range of properties (eg of tensile strength, compression and stress relaxation) can be optimised to suit particular applications. Preferably the proportion of ball clay : china clay is in the range 20 : 1 - 1 : 20, particularly 15 : 1 - 1 : 15, and especially 5 : 1 - 1 : 5. Preferably the kaolinitic clay forms not less than 75% by dry weight of the aqueous slurry.
To mask the whiteness that is due to the kaolinitic clay, a dark (and preferably black) pigment may be included in the slurry, suitably in an amount of 1-10% by dry weight. Examples are: black iron oxide; carbon black. The slurry may include a proportion, suitably 1-10% by dry weight, of mineral wool in order to improve drainage of water from the web on the conveyor of the paper-making machine.
The polymeric binder employed is preferably an elastomer, which may be natural rubber but is preferably synthetic, for example an acrylonitrile-butadiene copolymer. The elastomer is conveniently included in the slurry in the form of a latex. A cross-linking agent may optionally be incorporated, along with antioxidant.
The fibrillated poly(aromatic amide) fibres provide essentially the sole organic web-forming fibres in the process, and these are suitably employed at a freeness of 30-70 degrees Schopper Riegler. The fibres also provide reinforcement, both during "wet" stages of the paper- making process and during processing of the paper product into gaskets. Their reinforcing capacity for the kaolinitic clay matrix is particularly well retained at the high temperatures (280-300 degrees C) prevailing during IC engine operation. The material commercially available as Kevlar (registered trade mark) pulp is very suitably used. Preferably, the fibrillated poly(aromatic amide) or "aramid" fibres are used in an amount of 5-12% by dry weight of the aqueous paper-making slurry. From the sheet material produced by the method of the invention gaskets can be made by entirely conventional means, as by lamination onto each side of a metal sheet (plain, perforated, tanged or other); blanking of the laminate into the desired shape with appropriately spaced combustion chamber and other apertures; insertion of eyelets around the chamber apertures; impregnation with a silicone or other polymer to improve resistance to oil and aqueous anti-freeze solution; and coating of the surface to facilitate release from the cylinder head when the head is removed from the cylinder block.
The density of the sheet material product will ordinarily be in the range 700-1500 kg/m3 .
The invention is further illustrated by the following examples
EXAMPLE 1
A paper was prepared from an aqueous slurry having the following composition
% dry weight
Fibrillated poly( aromatic amide) fibres 8
Ball clay 71
Calcined china clay 5
Mineral wool 5
Nitrile rubber 6
Black iron oxide 5
Preparation of Slurry
(i) "Kevlar pulp" (fibrillated poly aromatic amide) in roll form was made into an aqueous slurry of solids content about 2% by weight and treated in a disc refiner at low load to disentangle the fibres without significantly shortening them. The freeness of the resulting pulp was 62 degrees Schopper Riegler.
(ii) The pulp of (i) (1.6 kg dry weight = 80 kg wet weight) was added to 200 litres of water at 60° C in a mixing tank and the diluted pulp was agitated vigorously. (iii) Mineral wool (1 kg dry weight of Swedish Rockwool having an average fibre length of 1.0 mm, water content of 25% and a shot content below 10%) was added to the diluted pulp.
(iv) Ball clay (14.2 kg; 96% < 20 μ , 67% < 2 μ), calcined china clay (1 kg; 90% < 10 u, 50% < 2 μ ) and black iron oxide (1 kg) were dispersed in 20 litres of water at 60° C and added to the pulp with agitation.
(v) The pH of the slurry was adjusted to 9 by the addition of aqueous ammonia.
(vi) 1.2 kg dry weight (= 2.5 kg wet weight) of a commercially available aqueous acrylonitrile- butadiene copolymer latex (pH 10.5, solids content 47%, acrylonitrile content 33%) was added and the mixture was agitated for 2 minutes.
(vii) The pH of the slurry was reduced by the addition of papermaker's alum (aluminium sulphate) until the supernatant liquid was found to be clear, indicating precipitation of the dispersed rubber particles onto the fibres, clay and pigment. Water at 60° C was then added to bring the total volume in the mixing tank to 500 litres, and mixing was continued for 3 minutes.
Preparation of Paper
The slurry of A above was made into flexible sheet material using a conventional Fourdrinier flat wire paper machine. Conventional polyacrylamide flocculating agent and anti-foaming agent were added to assist processing.
The paper was then densified by use of a 2-bowl calender to produce flexible sheet material having the following properties
Thickness 0.78 mm
Mass/unit area 990g/m2
Density 1270kg/m3
Tensile strength Machine direction 6.6 MPa Cross direction 5.1 MPa
Compression @ 10 MPa 15.0%
In addition the stress relaxation behaviour of the material was measured after laminating to plain steel core. A similar method to that described in ASTM F1276 was used, using an annular specimen of internal diameter 14.7 mm and external diameter 34.5 mm. A stress of 58.6 MPa was applied to the specimen and the residual stress was measured after exposure to a temperature of 300° C for 1.75 hours. The loss in stress as a percentage of the initial stress, and after normalisation to a facing thickness of 1.0 mm, was 35%.
EXAMPLE 2
Following generally the procedure of Example 1 , non- asbestos paper was made from a slurry whose composition was
% dry weight
Fibrillated poly(aromatic amide) fibres 8
Calcined china clay 76
Ball clay 5
Nitrile rubber 6
Black iron oxide 5
The calcined china clay, ball clay and black iron oxide were mixed before addition to the diluted pulp, and no pH adjustment was made prior to addition of the nitrile rubber latex. The calcined china clay had a specific surface area (BET) of 12m2 /g, particle size 90% <10 μ , 50% < 2 p.
The resulting flexible sheet material had the following properties
Thickness 0.6 mm
Mass/unit area 690g/m2
Density 1160 kg/m3 Tensile strength
Machine direction 3.4 MPa
Cross direction 2.3 MPa
Compression @ 10 MPa 12.0%
The stress relaxation of samples of this material after laminating to plain steel core was 27%.
Gaskets suitable for use on the cylinder heads of automobile engines were produced from the material by the conventional steps: (i) Lamination of the paper onto each side of plain steel core (ii) Blanking of the required gasket shape (iii) Insertion of steel eyelets into the combustion chamber bore holes of the gasket ( iv) Impregnation of the gasket with a silicone (v) Surface-coating with a release agent
The resulting gaskets gave excellent fluid-sealing performance in test engines.
EXAMPLE 3
Following generally the procedure of Example 1, a non- asbestos paper of improved properties can be made from a slurry of the following composition:
% dry weight Fibrillated poly(aromatic amide) fibres 8
Calcined china clay 20
Ball clay 65
Nitrile rubber 6
Carbon black 1

Claims

1 A method of making non-asbestos flexible sheet material suitable for use in gaskets for the cylinder head of an internal combustion engine, by dewatering a layer of aqueous slurry and compressing and drying the dewatered layer, in which the aqueous slurry employed is substantially free from cellulose and contains the following ingredients in the following proportions by dry weight:
kaolinitic clay 65-90% organic fibres consisting essentially of fibrillated poly(aromatic amide) fibres 5-15% polymeric binder 4-10%
the kaolinitic clay comprising both china clay and ball clay.
A method according to claim 1, in which the kaolinitic clay forms at least 75% by dry weight of the slurry.
A method according to claim 1 or 2, in which the kaolinitic clay is predominantly calcined china clay, the rest being ball clay. A method according to claim 1 or 2, in which the kaolinitic clay is predominantly ball clay, the rest being calcined china clay.
A method according to any of claims 1 to 4 , in which the weight proportion ball clay : china clay is in the range 15 : 1 - 1 : 15.
A method according to any of claims 1 to 5 , in which the slurry also contains mineral wool, in an amount of 1-10% by dry weight.
A method according to any of claims 1 to 6, in which the polymeric binder is a synthetic elastomer.
A method according to claim 7, in which the synthetic elastomer is included in the slurry in the form of a latex.
A method according to any of claims 1 to 8, in which the polymeric binder is an acrylonitrile-butadiene copolymer.
A method according to claim 1, substantially as described with reference to Example 1 herein. A method according to claim 1 , substantially as described with reference to Example 2 herein.
A method according to claim 1, substantially as described with reference to Example 3 herein.
A cylinder head gasket comprising non-asbestos flexible sheet material which is substantially free from cellulose, is made according to any preceding claim, and is secured to a metal support.
PCT/GB1991/002061 1990-11-29 1991-11-21 Non-asbestos flexible sheet material WO1992009744A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB909025983A GB9025983D0 (en) 1990-11-29 1990-11-29 Non-asbestos flexible sheet material
GB9025983.9 1990-11-29

Publications (1)

Publication Number Publication Date
WO1992009744A1 true WO1992009744A1 (en) 1992-06-11

Family

ID=10686198

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1991/002061 WO1992009744A1 (en) 1990-11-29 1991-11-21 Non-asbestos flexible sheet material

Country Status (2)

Country Link
GB (2) GB9025983D0 (en)
WO (1) WO1992009744A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0522441A2 (en) * 1991-07-10 1993-01-13 Akzo N.V. Composition based on aramid staple fibers
WO1994002760A1 (en) * 1992-07-22 1994-02-03 Armstrong World Industries, Inc. Liquid sealing gasket sheet materials

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2314569B (en) * 1996-06-27 2000-01-26 T & N Technology Ltd Gasket paper

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2499463A1 (en) * 1981-02-10 1982-08-13 Texon Inc COMPRESSIBLE SHEET MATERIAL, FOR JOINTS, HAVING HIGH-TEMPERATURE RESISTANT ORGANIC FIBERS AND PROCESS FOR PRODUCING THE SAME
GB2138854A (en) * 1983-04-27 1984-10-31 T & N Materials Res Ltd Gasket paper
GB2138855A (en) * 1983-04-27 1984-10-31 T & N Materials Res Ltd Gasket paper

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2499463A1 (en) * 1981-02-10 1982-08-13 Texon Inc COMPRESSIBLE SHEET MATERIAL, FOR JOINTS, HAVING HIGH-TEMPERATURE RESISTANT ORGANIC FIBERS AND PROCESS FOR PRODUCING THE SAME
GB2138854A (en) * 1983-04-27 1984-10-31 T & N Materials Res Ltd Gasket paper
GB2138855A (en) * 1983-04-27 1984-10-31 T & N Materials Res Ltd Gasket paper

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0522441A2 (en) * 1991-07-10 1993-01-13 Akzo N.V. Composition based on aramid staple fibers
EP0522441A3 (en) * 1991-07-10 1993-09-08 Akzo N.V. Composition based on aramid staple fibers
WO1994002760A1 (en) * 1992-07-22 1994-02-03 Armstrong World Industries, Inc. Liquid sealing gasket sheet materials
GB2275975A (en) * 1992-07-22 1994-09-14 Armstrong World Ind Inc Liquid sealing gasket sheet materials
GB2275975B (en) * 1992-07-22 1995-08-09 Armstrong World Ind Inc Liquid sealing gasket sheet materials

Also Published As

Publication number Publication date
GB9025983D0 (en) 1991-01-16
GB9124747D0 (en) 1992-01-15
GB2250302A (en) 1992-06-03
GB2250302B (en) 1994-05-18

Similar Documents

Publication Publication Date Title
US4529663A (en) Flexible, asbestos-free gasket material
CA1205608A (en) Flexible sheet material
CA1204255A (en) Flexible sheet material
US5294300A (en) Production method of expanded graphite sheet and expanded graphite sheet obtained thereby
EP0604632B1 (en) Liquid sealing gasket sheet materials
US4786670A (en) Compressible non-asbestos high-temperature sheet material usable for gaskets
US4443517A (en) Gasketing material
EP0023512A1 (en) Sheet material containing exfoliated vermiculite.
EP0646101B1 (en) Non-asbestos flexible sheet material
WO1992009744A1 (en) Non-asbestos flexible sheet material
EP0579879B1 (en) Production method of expanded graphite sheet and expanded graphite sheet obtained thereby
EP0027706A1 (en) Latex bound non-asbestos paper
GB2047298A (en) Gasket Material
GB2138854A (en) Gasket paper
FI66947C (en) FLEXIBELT ARKMATERIAL
GB2037343A (en) Gasket Material and Method of Manufacture Thereof
EP0916001B1 (en) Gasket paper

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE

122 Ep: pct application non-entry in european phase