JPS5829872A - Joint sheet - Google Patents

Abstract

PURPOSE:To provide a joint sheet consisting of a specified organic fiber, a natural or synthetic rubber, a rubber chemical and a filler, and exhibiting mechanical strength and sealing property not at all inferior to those of asbestos, without the use of asbestos. CONSTITUTION:Organic fibers with hair root-like branches or whiskers and/or crooked organic fibers are homogeneously mixed with a rubber chemical and a filler by using an organic solvent solution of a natural or synthetic rubber as a binder. The mixt. is fed into a calender roll to form a laminated roll on the surface of a hot roll and the roll is cut open into the joint sheet. Ordinary organic fibers and inorganic fibers other than asbestos may be blended with the above-mentioned fibrillated organic fibers and crooked organic fibers to improve the strength and sealing property of the joint sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in joint sheets used as gasket base materials.

Conventionally, the joint sheet of this virtue is 1-asbestos joint sheet, which is widely used in a wide range of fields involving powerful drugs, such as IK ships, chemical industry, automobiles, and equipment.

The asbestos joint sheet described in 1.1 is a sheet-like material made of asbestos fibers as a base material and rubber as a binder, heated and compressed into a dense and uniform cardboard shape.
7 class asbestos total 60-80 inches, solid content of natural or synthetic rubber dissolved in organic solvent 10-20 inches, and other rubber chemicals.

It is made from a material obtained by mixing fillers, etc., and is laminated on a hot roll.

However, the asbestos used in the asbestos joint sheet is a natural mineral, and in recent years, due to resource depletion and rising labor and transportation costs for mining, it has become difficult to obtain asbestos. Hazardousness is a problem even though it is not harmful to the human body.1
The use of asbestos is becoming regulated worldwide.

As mentioned above, the asbestos joint sheet has asbestos in its composition and includes all of the above-mentioned transition points, so it is important to develop a joint sheet that does not use asbestos. is proposed.

For example, Japanese Patent Application Laid-open No. 51-86659 discloses that heat-resistant inorganic materials such as glass twill fibers, ceramic fibers, rock wool inorganic fibers, and sericite mica are used as base materials, and are obtained by the same manufacturing method as the above-mentioned asbestos joint sheet. However, this joint sheet has a tensile strength of only about 115 to 1/4 of that of general asbestos joint sheets, and has physical properties that are inferior to asbestos joint sheets. It is considerably inferior to Intosheet, and has not reached the point where it can be put to practical use.

In view of the above-mentioned problems, the present invention provides a joint sheet that uses fibers other than asbestos and has physical properties that are comparable to the mechanical strength and sealing performance of conventional asbestos joint sheets. The main purpose is to

In order to accomplish the above-mentioned purpose, the present inventor conducted a research experiment on Akisui, and found that the base fiber other than asbestos has hair root-like branches and a large number of whiskers. So-called fibrillated organic fibers and/or bent organic fibers are used.

Using natural rubber or synthetic rubber dissolved in an organic solvent as a binder, the rubber chemicals and optical material are uniformly kneaded, and the resulting mixture is mixed with a calender roll (heat rolled and cold roll) for joint sheet production. K is supplied to form a layer on the surface of the heated roll, and the sheet obtained by cutting this sheet has high strength comparable to that of an asbestos joint sheet and a pressure m NM yc % that is highly praised as a gasket. This invention was completed based on this discovery.

In other words, according to research experiments conducted by the present inventors, compared to fibers of the same length, fibrillated fibers or bent fibers are easier to mix, and the state of mixing with other materials and the state of dispersion of the fibers are both better. It was confirmed that the fibers were strongly entangled, and that the mixed wire I+JIJ (nine) was obtained in a manner very similar to that of conventional asbestos joint sheets. It was also confirmed that the method can be easily manufactured and completed.

The fibers used in the present invention are most preferably cellulose-based bulbs, and synthetic polymer fibers such as aromatic and aromatic boria ξ-do fibers, acrylic fibers, and polyethylene fibers.

Hair root-like branches and numerous whiskers are formed in the multimolecular fibers. As a so-called fibril means.

For example, there is a method in which the fibers are wet beaten in a beater, dried, and then treated in a dry opening machine (disinching grater), which makes it easier to form fibrils.

Among the above-mentioned fibers, cellulose pulp originally has a bent shape and has some hair-like branches and whiskers, so it can be used as is without fibrillation.

In this invention, other ordinary organic fibers and inorganic fibers other than asbestos may be mixed with the fibrous organic fibers and bent organic fibers.
By using these fibers in combination, the strength and sealing properties of the joint sheet can be further improved.

The amount of fibrillated fibers or bent fibers to be distributed is preferably 5 to 50% by weight, preferably 10 to 25% by weight of the total amount, and when ordinary organic fibers and inorganic fibers are used together, 5 to 70 qb by weight, When only organic fibers are used together, it is preferable to add the amount in the range of 10 to 20% by weight.On the other hand, the appropriate amount of natural rubber or synthetic rubber is in the range of 5 to 40 m violet. A range of 20 to 80% is preferable.

Example (1) Composition material: Aromatic polyamide fiber #I 15NBR' monotifiprylated
15 filler
68 Vulcanizing agents
2 Toluene: α7 for 1 kg of the above mixture
However, as the fibrillated aromatic polyamide fiber, a product manufactured by DuPont under the trade name "Kevlar Pulp" was used.

The above rubber (NBB) is mixed with a solvent in advance. After ii, the above-mentioned composition materials were mixed uniformly, the obtained mixed material was supplied to a calender roll for manufacturing an asbestos joint sheet, laminated and molded on the surface of the hot roll, and then cut to obtain a sheet. .

Example (2) Composition material Weight% fibrillated acrylic fiber 158Bi (i5 Optical filler 68 Bi-based drug
2 Torr 1 kg of the above mixture
However, the length of fibrillated acrylic fiber is 6#v.
Fi, the one obtained by beating acrylic fiber chops with a diameter of 20 μm in water with a beater and drying them with water was used.

The mixture of the above composition materials was molded in the same manner as in Example 11 (P4IIJf) to obtain a sheet.

Example (3) Composition material Side 0 pulp
15NR15 Filler 68 Vulcanizing agent
2 Toluene: Used at a ratio of α7t per 1 kg of the above mixture.

However, the pulp used was one obtained by pulverizing and opening commercially available cardboard-like pulp base paper using a pulverizer to form a cotton-like pulp.

The mixture of the above composition materials was molded in the same manner as in Example (1) to obtain a sheet.

Example (4) Composition materials Button 0 crushed open cotton pulp 10.5 fibrillated polyethylene fiber 4.5 NR15 optical filler 68 vulcanizing agent
2. Toru Koton 2 Used at a ratio of α7t per 1 kg of the above mixture.

A mixture of the above composition materials was molded in the same manner as in Example (11) to obtain a sheet.

Between I & I (5) Composition material: Heavy disaster-resistant fiber
4.5NR15 Light, propellant 68 Vulcanizing chemicals
2. Used at a ratio of α7t per 1 kg of the above mixture.

The mixture of the above composition materials was molded in the same manner as in Example (1) to obtain a sheet.

Example (6) Composition material Weight % fibrillated aromatic polyamide fiber 7 Manufactured by Dupont, part name: "Keplar pulp" NB)L
15 filler
76 Vulcanizing agent 2 Toluene: The above mixture @ 1 kg Used at a ratio of α7t to K A mixture of the above composition materials was molded in the same manner as in Example (11) to obtain a sheet.

Comparative Example (1) Composition Materials Heavy-duty disaster-resistant fiber 15 NR1b Filler 68 Vulcanizing agent 2 Toru-Kon-2 Above mixture 1 Used at a ratio of α5t to ktJ.

The mixture of the above composition materials was molded in the same manner as in Example (1) to obtain a sheet.

Comparative Example (2) Composition Materials 1% Aromatic Polyamide Tekop 15NBR15 Filler 68 Kashu-based Mulberry Agent 2 Toluene: Used at a ratio of α7t per 1 kg of the above mixture.

The mixture of the above composition materials was molded in the same manner as in Example (1) to obtain a sheet.

Comparative example (3) Composition material Weight thiacrylic fiber chip 158B
15 Optical filler 68 Conditioning agent 2 Toluene: Used at a ratio of α7t to 1 part of the above mixture.

The mixture of the above composition materials was molded in the same manner as in Example (1) to obtain a sheet.

Typical physical property values of the above Examples and Comparative Examples are shown in the table below.

aυ However, the above physical property values are calculated by adding 61J according to the method of JIS 3455.

Those using bent fibers and bent fibers.

It has been revealed that this material has higher strength and sealing properties than those made of ordinary rod-shaped fibers.

As stated above, - According to the invention, h-cotton N1.
A joint sheet with high strength and good sealing performance can be obtained without using fibers, and this can be a great contribution to the apple industry.

Procedural amendment (voluntary) 1981
September 1/ρ day Patent 1 Indication Patent Application No. 1983-128332 of Chojima Taharushodon 1 case 2, Name of the invention Joint sheet 3, Relationship with the amended person case t￥j permission application, name Japan Ashest Co., Ltd. 4, agent postal code 100.

Address 2-4-1 Marunouchi, Chiyoda-ku, Tokyo ♂ 1 3 5 Date of amendment order Date of amendment 1932 Contents of amendment to Japanese Patent Application No. 128332/1983 1, “Rano” in shell number 5, line 19 of the specification I corrected myself, ``Korarano.''

2. Correct the 9th negative lines 6 to 13 as follows.

"Example (5) Composition Materials Fibrillated aromatic polyamide fiber 10.5 flame resistant fiber 4.5N
15 Filling cross material 68 Vulcanized yarn agent 2 Torukoton2 The above mixture was used at a ratio of 0.7j to 1kp.

3. ``Flame-resistant fiber'' on page 1, line 9.
4 Correct ``chimp'' in line 9 of the 11th line of the same sentence to ``chop''.

Claims (1)

[Claims] (11) organic fibers having hair-like branches and numerous whiskers;
Joint sheet with f imitation. (2) Organic fibers and/or bent organic fibers having hair-like branches or multiple whiskers, ordinary organic fibers and non-emission/textured fibers, natural rubber and /l or synthetic rubber,
A joint sheet characterized by comprising a rubber chemical and a filler.