JPH03212480A - joint sheet - Google Patents

Abstract

PURPOSE:To obtain a joint sheet, composed of a three-layer structure of a core material composed of metal fiber and organic fiber and surface materials composed of the organic fiber and having mechanical strength and sealing performance not inferior to that of asbestos fiber without using the asbestos fiber. CONSTITUTION:The objective joint sheet composed of (A) a fibrous material with a three-layer structure composed of a core material of 5-60wt.% nonferrous metal fiber and/or iron-based metal fiber subjected to rust preventing treatment, 1-30wt.% organic fiber with the front and back two layers of surface materials, (B) a rubber material, (C) a rubber chemical, (D) a filler and (E) other additives.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to improvements in joint sheets used as gasket base materials.

[Prior art] Conventionally, joint sheets for gaskets are made by kneading a composition of asbestos as a base fiber and rubber as a binder, adding a solvent to the composition, and kneading the mixture with a heating roll at about room temperature. Sheet materials have been used for many years, which are placed between calender rolls consisting of a roll of asbestos, laminated with the mixture on the surface of the heated roll, and vulcanized into a sheet while evaporating the solvent. Since the toxicity has been viewed as a problem, non-asbestos joint sheets that do not use asbestos fibers have been proposed as an alternative and are being put into practical use.

[Problems to be Solved by the Invention] Regarding non-asbestos joint sheets, sheets made of various inorganic fibers other than asbestos and combined with organic fibers and metal fibers have been proposed and put into practical use. Its overall strength, including tensile strength, shear strength, compressive strength, and stress relaxation, is significantly inferior to that of asbestos-based joint sheets.

[Object of the Invention] The present invention has been made in view of the above problems, and uses fibers other than asbestos fibers, and is superior in mechanical strength and sealing performance to asbestos joint sheets. The main purpose of this is to provide a joint sheet with physical properties that are unique to conventional joint sheets.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a joint sheet made of a fiber material, a rubber material, a rubber chemical, a filler, and other additives, in which the fiber material is a non-ferrous metal. 5-60% by weight of fibers and/or anti-rust treated iron-based metal fibers
The fiber material is characterized by having a three-layer structure consisting of a core material consisting of 1 to 30% by weight of organic fibers, and two surface materials, front and back, each of which comprises 1 to 30% by weight of organic fibers.

Furthermore, the present invention provides a joint sheet made of a fiber material, a rubber material, a rubber chemical, a filler, and other additives, in which the fiber material is a non-ferrous metal fiber and/or an antirust-treated ferrous metal fiber. 60% by weight and organic fibers 1-3
It is characterized by having a three-layer structure consisting of a core material consisting of 0% by weight and 1 to 8% by weight of inorganic fibers excluding asbestos, and two surface materials on the front and back, the fibrous material consisting of 1 to 30% by weight of organic fibers. It is something that exists.

[Function] In the joint sheet with the above structure, the core material using organic fibers and metal fibers has excellent performance in tensile strength, shear strength, compressive strength, stress relaxation properties, etc. In addition, the surface material made only of organic fibers has good compatibility with the mating member and exhibits excellent sealing performance.

[Example code] The drawings show an embodiment of the present invention.

In the figure, 1 is a core material forming a joint sheet, and 2, 2 are surface materials.

Core material 1 is a fiber material that is mainly treated with anti-corrosion treatment (primer treatment) on organic fibers and non-ferrous metal fibers or iron fibers.
The one that has been given is used. On the other hand, for the surface material 2, only organic fibers are used as the fiber material.

The organic fibers include fibrillated aromatic polyamide fibers (trade name "Kevlar pulp"), phenolic fibers (
(Product name: "Kynol"), fully aromatic polyester fiber (
It is best to use fibers such as Pectran (trade name: "Pectran"), but it is not limited to these fibers.

The organic fiber is suitably used in an amount of 1 to 30% by weight, more preferably 10 to 15% by weight, in the sheet material composition (core material, surface material). If the organic fiber is less than 1% by weight, the strength of the sheet material will be insufficient, making sheeting difficult, and if it is more than 30% by weight, sheeting will be impossible, and even if it were possible, the desired properties would not be obtained. .

As the non-ferrous metal fibers, metal fibers of brass, aluminum, copper, zinc, etc. are preferably used.

Metallic fibers treated with iron-based fibers to prevent rust (primer treatment) not only have a rust-preventing effect, but also improve adhesion with other compounded materials, contributing to improved strength of sheet materials.

The metal fiber preferably has a fiber diameter of 10 to 100 μm and a fiber length of 5 to 151 μm. If the fiber diameter is 10 μm or less, the cost will be high, and if the fiber diameter is 100 μm or more,
The thickness of the sheet material tends to be non-uniform, which is undesirable.

The blending amount of the metal fiber is 5 to 5 in the sheet material composition (core material).
It is preferably 60% by weight, more preferably 10 to 30% by weight. If the amount of metal fiber is less than 5% by weight, no improvement in the strength of the sheet material can be expected by using the metal fiber, and if it is more than 60% by weight, it becomes impossible to form a sheet.

In addition to the organic fibers and metal fibers mentioned above, inorganic fibers other than asbestos can be blended as the fiber material of the core material 1. As this inorganic fiber, rock wool, carbon fiber, glass fiber, etc. are used. The blending amount thereof is preferably in the range of 1 to 8% by weight.

Compounding materials other than fibers and their blending amounts are shown below.

Rubber (NR, SBR, NBR, etc.) ・・・・・・5～
20% by weight, lennonol, cresol, etc.)...
...10-20% by weight rubber chemicals (sulfur, vulcanization accelerator.

carbon, catalpo, etc.) ・・・・・・5～
30% by weight filler (palite, clay)...
...A mixture obtained by adding a solvent to a composition consisting of 30 to 60% by weight or more of organic fibers, metal fibers, inorganic fibers excluding asbestos, and other compounding materials, and kneading the mixture with a heating roll at about room temperature. The desired joint sheet material can be obtained by placing the mixture between calender rolls consisting of a roll, laminating the mixture on the surface of the hot roll, and vulcanizing it into a sheet while evaporating the solvent. In that case, a material containing metal fibers is used as the core material of the joint sheet, and a material containing only organic fibers without metal fibers is used as the surface material of the joint sheet, and these are laminated to form a three-layer structure. By doing so, it becomes a jointed sheet product.6 In the jointed sheet configured with a three-layer structure as described above, the core material in which organic fibers and metal fibers are used as the fiber material is particularly important due to the combination of metal fibers. , the sheet material exhibits excellent tensile strength, shear strength, compressive strength, and stress relaxation properties.

In that case, when considering the use of organic fibers alone, organic fibers are bulky and have low density, so the blending amount is approximately 8 to 15%.
Since it is limited to a range of % by weight.

Organic fibers alone cannot increase the strength of sheet materials, but by adding metal fibers with high density,
It is characterized by improved intertwining of fibers, which increases the strength of the sheet material and at the same time provides a compound with good plate-making properties, and furthermore, the product characteristics can be changed by changing the blending ratio of the two.

In addition, inorganic fibers (
Sheet materials containing asbestos (excluding asbestos) can improve heat resistance along with increased strength.

On the other hand, the surface material laminated on the surface of the core material is made only of organic fibers, so it is more flexible than the core material, has better compatibility with the mating material, and exhibits excellent sealing performance. be done.

Next, a specific example (as a core material) of the present invention and a comparative example are shown below.

However, the fiber diameter of the brass, aluminum, and copper metal fibers is 20 μm, and the fiber length is 10 mm.

The table below shows the test results of a sheet material prepared by backing the mixture according to the above formulation using a conventional manufacturing method.

however, The non-asbestos upper section is kevlar pa Lupu 10% by weight, The lower row contains 15% by weight. It is.

Test method Tensile strength: ISR 453 Shear strength: Strength at breakage when shearing force is applied to both sides of a sheet (50 x 25 cabinets) adhesively held.

Compressive strength: Strength at breakage when a sheet (10 m opening) is pressurized.

Stress relaxation properties: JISR3453 Sealing performance test: Pressure surface 30 on sheet (69φ x 55φ)
Air pressure of 7 kgf/cd was passed through a sealed box to which 0 kgf/cd was applied for 10 minutes, and leakage was measured.

[Effects of the Invention] As described above, according to the present invention, since organic fibers and metal fibers are used together in the fiber material used for the core material of the joint sheet, it is possible to increase the amount of fiber used. Then,
Compared to conventional non-asbestos joint sheets, it can significantly improve overall performance such as tensile strength, shear strength, compressive strength, and stress relaxation.

In addition, according to the present invention, the metal fibers include non-ferrous metal fibers,
Since it uses iron-based fibers that have been treated with anti-corrosion treatment, there is no fear that the strength of the metal fibers will decrease due to rust, and it can be used for a long period of time.

[Brief explanation of drawings]

The drawing is a sectional view of a joint sheet showing an embodiment of the present invention. 1... Core material, 2... Surface material.

Claims (2)

[Claims] (1) A joint sheet consisting of a fiber material, a rubber material, a rubber chemical, a filler, and other additives, in which the fiber material contains 5 to 60% by weight of nonferrous metal fibers and/or antirust-treated ferrous metal fibers. a core material comprising 1 to 30% by weight of organic fibers, and a core material comprising 1 to 30% by weight of organic fibers;
A joint sheet characterized by having a three-layer structure consisting of two layers of surface material: front and back. (2) A joint sheet consisting of a fiber material, a rubber material, a rubber chemical, a filler, and other additives, in which the fiber material is a non-ferrous metal fiber and/or a rust-preventing treated ferrous metal fiber. A core material consisting of 1 to 30% by weight of organic fibers and 1 to 8% by weight of inorganic fibers excluding asbestos, and two surface materials on the front and back, the fiber material of which is 1 to 30% by weight of organic fibers. A joint sheet characterized by its structure.