JP3463902B2 - Sheet material and manufacturing method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material and a method for producing the same, more specifically, it exhibits excellent flexibility, sealing properties and heat resistance without using asbestos fibers, and further has chemical resistance. The present invention relates to a sheet material which can be used as a gasket or packing having excellent properties, particularly, resistance to CFC substitutes, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, asbestos sheets have been known as a sheet material used for gaskets, packings, etc. This conventional product generally includes asbestos as a base fiber and a binder. Although rubber and fillers were used as the material to provide flexibility, sealability, heat resistance and strength, asbestos, which is a natural product, has been
Along with the problems of resource depletion and the difficulty of obtaining resources, adverse effects on the human body have been pointed out, and their use is now being reconsidered.

For this reason, in the field of sheet materials as described above, research has been actively conducted to manufacture an asbestos sheet substitute using a fiber base material instead of asbestos. For example, as an alternative to asbestos, It has been proposed to use glass fibers, rock wool, ceramic fibers and the like, inorganic fibers such as carbon fibers or organic fibers such as aramid fibers, polyester fibers, polyacrylonitrile fibers and phenol fibers.

[0004]

However, the above-mentioned inorganic and organic fibers each have a larger fiber diameter than asbestos and are disadvantageous for forming a dense structure, which is sufficiently satisfactory. Sealing property is not obtained.

In order to compensate for this drawback, attempts have been made to improve the sealing property by heat fusion using polyolefin fibers having thermoplasticity, but these fibers have a temperature of about 180 ° C. or less. Remelted with
It has sufficient heat resistance.

Furthermore, recently, the use of another refrigerant in place of the CFCs that cause ozone depletion has been investigated, but a sheet material having sufficient durability against such CFC alternative solvents. Development is desired.

The present invention solves the above-mentioned drawbacks of the prior art, exhibits excellent flexibility, sealability and heat resistance without using asbestos fibers, and has chemical resistance, especially resistance to CFC substitutes. The purpose of the present invention is to provide a sheet material that can be used as an excellent gasket or packing, and a method for producing the sheet material.

[0008]

In order to achieve the above-mentioned object, the constitution of the sheet material adopted by the present invention is such that at least an inorganic filler other than asbestos and a rubber material (provided that a functional group reactive with a carbodiimide group is used). With the exception of) and the formula

[Chemical 13] (In the formula, R ₁ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group.)

[Chemical 14] (In the formula, R ₂ and R ₃ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group.)

[Chemical 15] (Wherein, R _4, R ₅ is a hydrogen atom, a lower alkyl group or a lower alkoxy group, X is an oxygen atom or a methylene group each represented.) 混抄a polycarbodiimide resin powder having a repeating unit represented by or Knead into a sheet,
The sheet-shaped material is softened by the polycarbodiimide resin powder.
Is it characterized by being heat-molded at a temperature above the point,
Alternatively, the sheet-like material having such a constitution and polycarbodiimide
After overlaying with the resin-treated reinforcement,
Heat molding at a temperature above the softening point of the carbodiimide resin powder
It is characterized by what is done.

In order to achieve the above object, the method of producing a sheet material according to the present invention comprises at least an inorganic filler other than asbestos, a rubber material, and a repeating unit substantially represented by the above formula. A polycarbodiimide resin powder having, and optionally a fiber component made of an organic fiber or an inorganic fiber is mixed or kneaded to form a sheet, and the sheet is heat-molded at a temperature equal to or higher than the softening point of the polycarbodiimide resin powder. Alternatively, or after superimposing a sheet-like material having such a configuration and a reinforcing material treated with a polycarbodiimide resin, heat molding at a temperature equal to or higher than the softening point of the polycarbodiimide resin powder. It is a feature.

The present invention will be described in detail below.

As described above, the first sheet material of the present invention
The aspect of, at least with an inorganic filler other than asbestos,
A rubber material, a polycarbodiimide resin powder having a repeating unit substantially represented by the above formula, and a fiber component of an organic fiber or an inorganic fiber which is added as necessary, and an inorganic filler of these. The material is not particularly limited as long as it is an inorganic filler other than asbestos. Specifically, fibers such as glass fiber, and clay, talc, barium sulfate, mica, vermiculite, calcium carbonate, silica, wollastonite, magnesium sulfate, potassium titanate, carbon black and the like powder,
Examples thereof include apple-like or whisker-like substances, or a mixture of these as appropriate.

As the rubber material, nitrile rubber (NB
R), styrene butadiene rubber (SBR), isoprene rubber (IR), chloroprene rubber (CR), butadiene rubber (BR), butyl rubber (IIR), ethylene-propylene rubber (EPM), ethylene vinyl acetate rubber (EVA),
Chlorinated polyethylene rubber (CPE), epichlorohydrin rubber (ECO), nitrile isoprene rubber (NI
R), fluororubber (FRM), silicone rubber (S
i), natural rubber (NR), and latexes thereof,
A conventionally known joint sheet or molding rubber can be used.

The polycarbodiimide resin used in the present invention is a known one, or can be produced in the same manner as a known one. {US Pat.
94l, 956; Japanese Patent Publication No. 47-33279; Org. Chem, 28 , 2069-2075.
(1963) Chemical Review l98
l, vol. 8l. No. 4, 619 to 62l, etc.}, for example, it can be easily produced by a condensation reaction involving decarbonization of an organic diisocyanate in the presence of a carbodiimidization catalyst.

The organic diisocyanate used for producing the above polycarbodiimide resin may be of any type such as aliphatic type, alicyclic type, aromatic type and aromatic-aliphatic type. May be used alone or in combination of two or more.

The polycarbodiimide resin used in the present invention has the following formula -RNN = C = N- (wherein R represents an organic diisocyanate residue).
The homopolymers or copolymers of at least 1 type of repeating unit represented by

As R in the above formula, which is an organic diisocyanate residue, an aromatic diisocyanate residue is particularly preferable (here, the organic diisocyanate residue is obtained by removing two isocyanate groups (NCO) from the organic diisocyanate molecule). I say the rest). Specific examples of such an organic diisocyanate include formula (1),

[Chemical 16] Or formula (2),

[Chemical 17] Or formula (3),

[Chemical 18] What is represented by can be illustrated.

Explaining the substituents in the above formula, R
₁ , R ₂ and R ₃ are a hydrogen atom, a lower alkyl group represented by a methyl group, an ethyl group, a propyl group, a butyl group or the like or a corresponding lower alkoxy group, and R ₄ and R ₅ are a hydrogen atom, R
A lower alkyl group or a lower alkoxy group similar to _{1 to} R ₃ is represented, and X is an oxygen atom or a methylene group.

Specifically, as the organic diisocyanate represented by the above formula (1), 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,
Tolylene diisocyanate such as a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, 1-methoxyphenyl-2,4-diisocyanate, etc., and an organic diisocyanate are represented by the above formula (2). Examples thereof include o-tolidine diisocyanate, and further, those in which the organic diisocyanate is represented by the above formula (3) include 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyl ether diisocyanate and 3,3 ′. -Dimethyl-4,4'-diphenyl ether diisocyanate and the like can be mentioned, respectively, and these diisocyanates can be used alone or as a mixture of two or more kinds.

The reaction for converting the above organic diisocyanate into a polycarbodiimide resin is carried out in the presence of a carbodiimidization catalyst. Examples of the carbodiimidization catalyst include 3-methyl-1-phenyl-2-phosphorene-1- Phosphorene oxides such as oxides can be mentioned.

The powdery polycarbodiimide resin used in the present invention is prepared by spray-drying a polycarbodiimide resin solution described in, for example, JP-A-5-239223, or DJ Lyman, Die Makromol. Chem., 6
7, 1 (1963), LM Alberino et al. (J. Appl. Polym. Sc
i., 21, 1999 (1977)) and the like, and a method of collecting a powdery product precipitated by reacting in a general solvent, and the like.

Since the polycarbodiimide resin powder used in the present invention is in powder form, it can be uniformly dispersed in the sheet material, and it should be uniformly and densely packed between the inorganic filler other than asbestos and the fiber component described later. Therefore, the toughness and sealing property of the sheet material are improved.

In the present invention, in addition to the above components, an appropriate fiber component may be added if necessary, and the fiber components include organic fibers and inorganic fibers, specifically, polyamide fibers, aramid fibers, Examples thereof include carbon fibers, polyester fibers, polyacrylonitrile fibers, pulps thereof, and celluloses (cotton, hemp, pulp, etc.).

The proportion of each component described above may be appropriately determined according to the purpose of use or the conditions. For example, inorganic filler other than asbestos 30 to 90% by weight rubber material 5 to 50% by weight polycarbodiimide resin powder 1-50 wt% Fiber component The range of 0-50 wt% can be mentioned.

On the other hand, the second embodiment of the sheet material of the present invention requires at least an inorganic filler other than asbestos, a rubber material, and a polycarbodiimide resin powder having substantially the repeating unit represented by the above formula. According to the present invention, a sheet-like material composed of a fiber component of an organic fiber or an inorganic fiber added according to the above, that is, the sheet material of the present invention described above is further applied with a reinforcing material treated with a polycarbodiimide resin.

As the polycarbodiimide resin used in the sheet material of the present invention having the above-mentioned constitution, it is convenient to use, for example, the one used when the above-mentioned polycarbodiimide resin powder is produced. Incidentally, as a general method for producing a polycarbodiimide resin, D. J. Lyman et al. (Die M
acromol. Chem. , 67, 1 (196
3)), B. Dyer et al. (J. Amer. Chem. S
oc. , 80, 5495 (1958)), L.S. M. Al
berino et al. (J. Appl. Polym. Sc
i. , 21, 1999 (1977)), T.W. W. Cam
pbell (J. Org. Chem., 28, 2069).
(1963)) and the like, and JP-A-51-61599.
And Japanese Patent Application Laid-Open No. 2-292316.

The reinforcing material used in the sheet material of the present invention is, for example, a woven fabric, a non-woven fabric or a paper-like material made of inorganic fibers or organic fibers other than asbestos, polyester film, polyamide film, polycarbonate film, polyimide film. Examples thereof include a polycarbodiimide film and a metal plate such as a stainless plate, an iron plate, a copper plate, and an aluminum plate. The concept of "reinforcement material treated with polycarbodiimide resin" in the present invention includes a film made of polycarbodiimide resin itself.

In any of the embodiments of the sheet material of the present invention, since the fiber component is used as a reinforcing material, it is not necessary to add it when strength is not required. The same applies to the treated reinforcing material.

Further, the sheet material of the present invention may have a multi-layered structure comprising a sheet-like material and a reinforcing material. For example, both sides of the sheet-shaped material can be reinforced with a reinforcing material, or a sheet-shaped material can be further applied to the reinforcing material.

Thus, the sheet material of the present invention characterized as described above is at least an inorganic filler other than asbestos, a rubber material, and a polycarbodiimide resin having substantially the repeating unit represented by the above formula. A sheet-like material obtained by mixing or kneading the powder and, if necessary, a fiber component of an organic fiber or an inorganic fiber, or a sheet-like material having such a constitution and a reinforcing material treated with a polycarbodiimide resin were superposed. It can be obtained by the production method of the present invention, in which the product is heat-molded at a temperature equal to or higher than the softening point of the polycarbodiimide resin powder.

The thermoforming of the sheet-like material obtained by the method for producing a beater sheet or the method for producing a joint sheet,
This can be done by using well-known means, or
As the heating temperature, a numerical value of 150 ° C. or higher can be exemplified.

In the production of the sheet material of the present invention,
An organic binder such as an acrylic resin emulsion, a phenol resin emulsion, a polyvinyl alcohol emulsion, a rubber emulsion, or the like can be added within a range that does not adversely affect the obtained sheet material.
Incidentally, among the above-mentioned fillers, clay, talc, silica, wollastonite, mica, etc. also function as a binder and can improve the strength of the obtained sheet material. Therefore, in the present invention, the filler and the binder are combined. There is no clear distinction between them.

[0032]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 (1) Preparation of polycarbodiimide resin powder 675 g of MDI (4,4'-diphenylmethane diisocyanate) and 71.4 g of phenyl isocyanate were mixed with 2458 g of tetrachloroethylene to prepare a carbodiimidization catalyst (3-methyl-1-phenyl). (2-phospholen-1-oxide) (1.5 g) was reacted at 120 ° C. for 4 hours to obtain a pale yellow and transparent polycarbodiimide resin solution (resin concentration 20%). This solution was cooled to 40 ° C. for 12 hours to obtain a slurry polycarbodiimide resin having a viscosity of 270 cp. The slurry polycarbodiimide resin was spray-dried under the conditions of a drying temperature of 60 ° C., an air pressure of 2 kg / cm ² , and a slurry supply rate of 1 l / h to obtain a pale yellow powder.

(2) Manufacture of sheet material Polycarbodiimide resin powder 12% by weight Inorganic filler 65% by weight Rubber material (NBR latex solid content) 23% by weight Papermaking was carried out by mixing the composition having the above-mentioned composition to prepare a sheet. . Next, a glass cloth having a thickness of 0.1 mm was applied to a solution of polycarbodiimide resin (polymer concentration: 5% by weight, solvent:
It was immersed in tetrahydrofuran) and dried. Resin content is 2
A reinforcing material having a content of 0% by weight and having a surface and a portion between glass fibers treated with a polycarbodiimide resin was obtained. Both sides of this reinforcing material were sandwiched between the sheets obtained by the above papermaking,
A sheet having a thickness of 0.5 mm was obtained by heat and pressure molding at ℃.
The polycarbodiimide resin solution was obtained by reacting 4,4′-diphenylmethane diisocyanate (MDI) with a carbodiimidization catalyst in tetrahydrofuran (THF) (hereinafter, polycarbodiimide solution using tetrahydrofuran as a solvent). Was manufactured in a similar manner).

The tensile strength and sealing property of the obtained sheet and the resistance to freon (JIS for R12 and R134a)
According to R-3453, the measurement result of the tensile strength change rate after immersion at 70 ° C. for 24 hours) was examined. The sealing characteristics are as follows. First, the obtained sheet is punched out into a predetermined shape to form a gasket, which is then inserted between the flange surfaces and tightened with a torque wrench at 100 kg / cm ² , and then the internal pressure of 7 kg / cm. Nitrogen ( ² ) was flowed and nitrogen leakage from the flange was collected for 10 minutes by the water replacement method, and the volume was taken as the amount of leakage to obtain a value showing the sealing characteristics.

Example 2 Polycarbodiimide resin powder produced in Example 1 15% by weight Inorganic filler 65% by weight Rubber material (NBR latex solid content) 20% by weight The composition of the above composition was mixed to form a sheet, and a sheet was prepared. Created. Next, a solution of polycarbodiimide resin (polymer concentration: 3
Wt%, solvent: tetrachloroethylene) was sprayed and dried to obtain a reinforcing material treated with a polycarbodiimide resin. Both sides of this reinforcing material are sandwiched between the sheets obtained by the above papermaking, and heat-pressed at 200 ° C to form a sheet having a thickness of 0.5.
A sheet of mm was obtained. The tensile strength, sealability and CFC resistance of the obtained sheet were examined. The above polycarbodiimide resin solution is 2,4-tolylene diisocyanate /
2,6-Tolylene diisocyanate mixture (mixing ratio 8
0:20 [TDI]) was obtained by reacting it with a carbodiimidization catalyst in tetrachloroethylene (hereinafter, a polycarbodiimide resin solution using tetrachloroethylene as a solvent was produced by the same method).

Example 3 Polycarbodiimide resin powder produced in Example 1 14% by weight Inorganic filler 65% by weight Rubber material (NBR) 21% by weight Into the composition having the above composition, an appropriate amount of toluene (to the total weight of the composition) was added. (Approximately 80% by weight) was added and kneaded with a kneader, and then molded with a calendar roll to obtain a sheet-like material. Next, a carbon cloth having a thickness of 0.15 mm was dipped in a solution of polycarbodiimide resin (polymer concentration 5% by weight, solvent: tetrachloroethylene), dried and treated with a polycarbodiimide resin having a resin content of 5% by weight. Got Both sides of this reinforcing material were sandwiched between the sheets obtained by the above papermaking, and heat-pressed at 200 ° C. to obtain a sheet having a thickness of 0.5 mm. The tensile strength, sealability and CFC resistance of the obtained sheet were examined.

Example 4 Polycarbodiimide resin powder produced in Example 1 17% by weight Inorganic filler 68% by weight Rubber material (NBR, acrylic mixed rubber latex solids) 15% by weight Papermaking by mixing the composition of the above-mentioned composition And created the sheet. Then, a solution of polycarbodiimide resin (polymer concentration: 3% by weight, solvent: tetrahydrofuran) was sprayed on a stainless steel plate having a thickness of 0.1 mm and dried to obtain a reinforcing material treated with the polycarbodiimide resin. Both sides of this reinforcing material were sandwiched between the sheets obtained by the above method,
A sheet having a thickness of 0.6 mm was obtained by heat-press molding at ℃.
The tensile strength, sealing characteristics and CFC resistance of the obtained sheet were examined.

Example 5 (1) Preparation of polycarbodiimide resin powder 600 g of MDI (4,4'-diphenylmethane diisocyanate) and 23.8 g of phenylisocyanate were mixed with 3840 g of tetrachloroethylene to prepare a carbodiimidization catalyst (3-methyl-1-phenyl). 2-phospholen-1-oxide) (10 g) was reacted at 120 ° C. for 4.5 hours. The reaction solution is cooled to room temperature to form a precipitate, and the precipitate is separated by filtration, dried and pulverized,
A powder of polycarbodiimide resin was obtained.

(2) Manufacture of sheet material Polycarbodiimide resin powder 15% by weight Inorganic filler 52% by weight Aramid pulp 10% by weight Rubber material (NBR latex solids) 23% by weight 18 after creating
A sheet having a thickness of 05 mm was obtained by heat-press molding at 0 ° C.
The tensile strength sealing property and CFC resistance of the obtained sheet were examined.

Example 6 Polycarbodiimide resin powder produced in Example 5 20% by weight Aramid pulp 5% by weight Cellulose pulp 2% by weight Inorganic filler 58% by weight Rubber material (NBR) 15% by weight Toluene was added to the above composition. The appropriate amount (about 80% by weight relative to the total weight of the composition) was added, and the mixture was kneaded by a kneader and formed into a sheet by a roll. This sheet was heated and pressed at 180 ° C. to obtain a sheet having a thickness of 0.7 mm. The tensile strength, sealing characteristics and CFC resistance of the obtained sheet were examined.

Example 7 (1) Preparation of polycarbodiimide resin powder 100 g of 80-TDI (8: 2 mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate) and MDI (4,4 ') -Diphenylmethane diisocyanate) 575 g and phenyl isocyanate 3
5.7 g and tetrachloroethylene (2700 g) in carbodiimidization catalyst (3-methyl-1-phenyl-2-
Phosphorene-1-oxide) (1.4 g) was reacted at 120 ° C. for 4 hours to obtain a pale yellow and transparent polycarbodiimide resin solution. The solution was cooled to room temperature to form a precipitate, and the precipitate was filtered, dried, and pulverized to obtain a polycarbodiimide resin powder.

(2) Production of sheet material Polycarbodiimide resin powder 20% by weight Aramid pulp 3% by weight Carbon fiber 2% by weight Inorganic filler 60% by weight Rubber material (chloroprene latex solid content) 15% by weight The sheets were mixed and made into sheets. Then, a solution of polycarbodiimide resin (polymer concentration: 3% by weight, solvent: tetrachloroethylene) was sprayed onto a stainless steel plate having a thickness of 0.1 mm and dried to obtain a reinforcing material treated with the polycarbodiimide resin. Both sides of this reinforcing material were sandwiched between the sheets obtained by the above method, and heat-pressed at 200 ° C. to obtain a sheet having a thickness of 0.6 mm. The tensile strength, sealing characteristics and CFC resistance of the obtained sheet were examined.

Comparative Example 1 Tensile strength, sealing characteristics and CFC resistance of a commercially available non-asbestos joint sheet were examined.

The measurement results of Examples 1 to 7 and Comparative Example 1 are shown in Table 1 below.

[0046]

[Table 1]

[0047]

Since the sheet material of the present invention does not use asbestos fibers unlike conventional products, there is no need to worry about adverse effects on the human body. Further, it is excellent in flexibility, sealing property and heat resistance, and is excellent as a sheet material used for gaskets, packing, etc.

Further, the sheet material of the present invention has chemical resistance,
In particular, it has excellent durability against alternative CFC solvents.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI C08J 5/18 CEZ C08J 5/18 CEZ C08K 3/00 C08K 3/00 7/02 7/02 C08L 21/00 C08L 21/00 (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 79/00-79/08

Claims (19)

(57) [Claims] 1. An inorganic filler other than at least asbestos, a rubber material (excluding those having a functional group reactive with a carbodiimide group), and a compound represented by the formula: (In the formula, R ₁ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group), or a compound represented by the formula: (In the formula, R ₂ and R ₃ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group), or a compound represented by the formula: (Wherein, R _4, R ₅ is a hydrogen atom, a lower alkyl group or a lower alkoxy group, X is an oxygen atom or a methylene group each represented.) 混抄a polycarbodiimide resin powder having a repeating unit represented by or Knead into a sheet,
The sheet-shaped material is softened by the polycarbodiimide resin powder.
A sheet material, which is formed by heating at a temperature above a point . 2. An inorganic filler other than at least asbestos, a rubber material (excluding those having a functional group reactive with a carbodiimide group), and a compound represented by the formula: (In the formula, R ₁ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group), or a compound represented by the formula: (In the formula, R ₂ and R ₃ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group.), Or a compound represented by the formula: (Wherein, R _4, R ₅ is a hydrogen atom, a lower alkyl group or a lower alkoxy group, X is an oxygen atom or a methylene group each represented.) 混抄a polycarbodiimide resin powder having a repeating unit represented by or Knead into a sheet
Together with the sheet material and polycarbodiimide resin
After overlaying the above-mentioned reinforcement,
Molded by heating at a temperature above the softening point of the mid resin powder.
Sheet material characterized the door. 3. The polycarbodiimide resin powder is 5
The sheet material according to claim 1 or 2, which has a thermal decomposition temperature of 00 ° C or higher. 4. The sheet material according to claim 1, wherein two or more kinds of the polycarbodiimide resin powder are used. 5. The sheet material according to claim 1, further comprising a fiber component made of an organic fiber or an inorganic fiber. 6. The sheet material according to claim 5, wherein the fiber component is polyamide fiber, aramid fiber, carbon fiber, polyester fiber, polyacrylonitrile fiber, celluloses (cotton, hemp, pulp, etc.). 7. The sheet material according to claim 2, wherein the reinforcing material is a woven fabric, a non-woven fabric, a paper-like material or the like made of an inorganic fiber or an organic fiber other than asbestos. 8. The reinforcing material is a polyester film,
The sheet material according to claim 2, which is a polyamide film, a polycarbonate film, a polyimide film, a polycarbodiimide film, or the like. 9. The sheet material according to claim 2, wherein the reinforcing material is a metal plate such as a stainless plate, an iron plate, a copper plate, and an aluminum plate. 10. An inorganic filler other than asbestos in an amount of 30 to 30.
90% by weight, 5 to 50% by weight of a rubber material (excluding those having a functional group reactive with a carbodiimide group), and 1 to 1% of a resin component obtained by heating a polycarbodiimide resin powder to a temperature above its softening point. The sheet material according to claim 1, which contains 50% by weight and a fiber component of an organic fiber or an inorganic fiber in an amount of 0 to 50% by weight. 11. The sheet-like material contains 30 to 90% by weight of an inorganic filler other than asbestos, and 5 to 50% by weight of a rubber material (excluding those having a functional group reactive with a carbodiimide group). The sheet material according to claim 2, which contains 1 to 50% by weight of a resin component obtained by heating the polycarbodiimide resin powder to a temperature above its softening point and 0 to 50% by weight of a fiber component of an organic fiber or an inorganic fiber. . 12. The sheet material according to claim 2, comprising a sheet-like material having a plurality of layers and a reinforcing material having a plurality of layers. 13. An inorganic filler other than asbestos, a rubber material (excluding those having a functional group reactive with a carbodiimide group), and a compound represented by the formula: (In the formula, R ₁ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group), or a compound represented by the formula: (In the formula, R ₂ and R ₃ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group.) Or, a compound represented by the formula: (Wherein R ₄ and R ₅ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group, and X represents an oxygen atom or a methylene group, respectively) and mixed with a polycarbodiimide resin powder having a repeating unit represented by Knead into a sheet,
A method for producing a sheet material, comprising heat-molding the sheet-like material at a temperature equal to or higher than the softening point of the polycarbodiimide resin powder. 14. An inorganic filler other than at least asbestos, a rubber material (excluding those having a functional group reactive with a carbodiimide group), and a compound represented by the formula: (In the formula, R ₁ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group), or a compound represented by the formula: (In the formula, R ₂ and R ₃ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group.) Or, a compound represented by the formula: (Wherein R ₄ and R ₅ represent a hydrogen atom, a lower alkyl group or a lower alkoxy group, and X represents an oxygen atom or a methylene group, respectively) and mixed with a polycarbodiimide resin powder having a repeating unit represented by Along with kneading into a sheet-like material, the sheet-like material and the reinforcing material treated with a polycarbodiimide resin are superposed, and then heat-molded at a temperature equal to or higher than the softening point of the polycarbodiimide resin powder. Of manufacturing a sheet material to be used. 15. The polycarbodiimide resin powder is added to 2 parts.
The method for producing a sheet material according to claim 13 or 14, wherein one or more kinds are used. 16. The method for producing a sheet material according to claim 13, wherein the thermoforming is performed at a temperature of 150 ° C. or higher. 17. The method for producing a sheet material according to claim 13, further comprising a fiber component made of an organic fiber or an inorganic fiber. 18. An inorganic filler other than asbestos in an amount of 30 to
90% by weight, 5 to 50% by weight of a rubber material (excluding those having a functional group reactive with a carbodiimide group), 1 to 50% by weight of a polycarbodiimide resin powder, and a fiber component made of an organic fiber or an inorganic fiber. The method for producing a sheet material according to claim 13, wherein the content is 0 to 50% by weight. 19. The sheet-like material contains 30 to 90% by weight of an inorganic filler other than asbestos, and 5 to 50% by weight of a rubber material (excluding those having a functional group reactive with a carbodiimide group). The method for producing a sheet material according to claim 14, wherein the polycarbodiimide resin powder is 1 to 50% by weight and the fiber component of the organic fiber or the inorganic fiber is 0 to 50% by weight.