JP2022003265A - Rubber material for gaskets and gasket - Google Patents

Abstract

To provide a rubber material for gaskets that has excellent vibration-damping and vibration-insulating properties and can impart excellent gasket functions, and provide a gasket.SOLUTION: A rubber material for gaskets has: a nitrile rubber containing acryl nitrile of 30 mass% or more; and carbon black. A 100% modulus value in accordance with JIS K6251:2017 is 5.0 MPa or more, and a type A durometer hardness measured in accordance with JIS K6253-3:2012 is 90 or less.SELECTED DRAWING: None

Description

The present invention relates to a rubber material for a gasket and a gasket.

Currently, gaskets in which a rubber layer and a metal base material are laminated are used in various fields such as automobiles. Gaskets are required to have high sealing properties, and for this reason, improvements in compression set resistance (CS), stress relaxation properties, and rubber hardness have been studied. For example, Patent Document 1 discloses a metal gasket in which a plurality of metal sheets and a sealing material made of an elastic body are laminated.

In recent years, the hybridization and electrification of automobiles have progressed, and environmentally friendly automobiles such as fuel cell vehicles have been developed. Gaskets for motors, secondary batteries, gaskets for batteries such as fuel cells, and gaskets for power control units are used in these automobiles. Since motors are used in environment-friendly vehicles such as hybrid vehicles, electric vehicles, and fuel cell vehicles, vibration occurs when the motor is driven. Therefore, it is desired to suppress the vibration generated in these environment-friendly automobiles and the vibration caused by other devices such as motors.

Further, since the gasket is generally required to have a gasket function suitable for various uses, it is required to improve the gasket function. Therefore, it is also required to improve the vibration damping property and the vibration damping property as well as the gasket function.

International Publication No. 2011/024812

The present invention provides a rubber material for a gasket and a gasket that can impart a good gasket function as well as excellent vibration damping and vibration-proofing properties.

The rubber material for a gasket according to the present invention is a nitrile rubber containing rubber and carbon black, and the rubber contains 30% by mass or more of acrylonitrile, and has a 100% modulus value of 5.0 MPa in accordance with JIS K6251: 2017. It is characterized by the above, and the type A durometer hardness measured according to JIS K6253-3: 2012 is 90 or less.

In the rubber material for gaskets according to the present invention, the content of rubber contained in the rubber material is preferably 30% by mass or more and 65% by mass or less.

In the rubber material for gaskets according to the present invention, it is preferable that the carbon black has a primary particle diameter of 26 nm or more.

The rubber material for a gasket according to the present invention preferably contains more than 35 parts by mass of carbon black with respect to 100 parts by mass of the rubber.

The gasket according to the present invention includes a rubber layer containing the rubber material and a metal base material, and the rubber layer is provided on at least one surface of the metal base material.

According to the present invention, it is possible to provide a rubber material for a gasket and a gasket that can impart a good gasket function as well as excellent vibration damping and vibration isolating properties.

Hereinafter, embodiments of the present invention will be described in detail. The rubber material for a gasket according to the present embodiment (hereinafter, may be simply referred to as “rubber material”) contains nitrile rubber containing 30% by mass or more of acrylonitrile as rubber and carbon black as a reinforcing material. As for the physical characteristics of the rubber material, the 100% modulus value according to JIS K6251: 2017 is 5.0 MPa or more, and the type A durometer hardness measured according to JIS K6253-3: 2012 is 90 or less. Is. Here, the "100% modulus value" represents a value obtained by dividing the tensile force when a test piece of a rubber material is given 100% elongation by the cross-sectional area of the test piece before the test. When the 100% modulus value of the rubber material is 5.0 MPa or more, an appropriate elastic modulus is given to the rubber material, so that even when compressive stress is applied to the gasket, the rubber material from the gasket can be used. It is possible to suppress rubber. As a result, it is possible to obtain a rubber material that can satisfy the shaving characteristics required for the gasket and can impart a good gasket function. Further, when the type A durometer hardness of the rubber material is 90 or less, the dynamic spring constant of the rubber material can be reduced, and the transmission of vibration from the vibration source is effectively suppressed. Furthermore, by using nitrile rubber containing 30% by mass or more of acrylonitrile as a raw material for the rubber material, excellent vibration damping and vibration isolation are performed in the high temperature region (room temperature or higher region) necessary for application as a gasket for a housing. Demonstrate sex. As a result, as a gasket material, a rubber material capable of imparting excellent vibration damping and vibration damping properties can be obtained.

In the rubber material according to the present embodiment, the 100% modulus value according to JIS K6251: 2017 is 5.0 MPa or more. As a result, an appropriate elastic modulus is imparted to the rubber material, the shaving characteristics required for the gasket can be satisfied at the same time, and a rubber material capable of imparting a good gasket function can be obtained. The 100% modulus value of the rubber material is preferably 5.0 MPa or more, more preferably 8.0 MPa or more.

In the rubber material according to the present embodiment, the type A durometer hardness measured in accordance with JIS K6253-3: 2012 is 90 (points) or less. This makes it possible to reduce the dynamic spring constant of the rubber material, and the transmission of vibration from the vibration source is effectively suppressed. As a result, as a gasket material, a rubber material capable of imparting excellent vibration damping and vibration damping properties can be obtained. The type A durometer hardness of the rubber material is preferably 90 (points) or less, more preferably 85 (points) or less. Further, the lower limit of the type A durometer hardness of the rubber material is preferably 70 (points) or more from the viewpoint of the gasket characteristics.

(Rubber component)
The rubber (rubber polymer) composed as the main component of the rubber material is nitrile rubber containing 30% by mass or more of acrylonitrile. Nitrile rubber is a copolymer of butadiene and acrylonitrile, and may or may not be hydrogenated. The nitrile rubber includes, for example, an extremely high nitrile content (acrylic nitrile content 43% or more), a high nitrile content (acrylic nitrile content 36% or more and less than 43%), and a medium-high nitrile content. Examples thereof include various nitrile rubbers having an acrylic nitrile content of 31% or more and less than 36% and a medium nitrile content (acrylic nitrile content of 25% or more and less than 31%). In particular, by using a nitrile rubber containing 36% by mass or more of acrylonitrile, it is possible to obtain a rubber material capable of improving the vibration damping property and the vibration damping property in a high temperature region and imparting more excellent vibration damping property and the vibration damping property. Can be done. The nitrile rubber configured as a rubber component may be used alone or in combination of two or more.

Commercially available products of such nitrile rubber include the trade name "Nipol (registered trademark) DN3350" (acrylic nitrile content 33%: manufactured by Nippon Zeon Co., Ltd.) and the trade name "NANCAR (registered trademark) 3345" (acrylic nitrile content 33%:). Ssangyong Sangyo Co., Ltd.), trade name "N230S" (acrylic nitrile content 35%: manufactured by JSR), trade name "N220S" (acrylic nitrile content 41.5%: manufactured by JSR), trade name "Nipol (registered trademark) ) DN003 ”(acrylonitrile content 50%: manufactured by Nippon Zeon Co., Ltd.) and the like.

The content of rubber contained in the rubber material, that is, the rubber polymer fraction is preferably 30% by mass or more and 65% by mass or less, and more preferably 45% by mass or more and 62% by mass or less. The rubber content is set in the range of 30% by mass or more and 65% by mass or less depending on the type of carbon black described later so that the desired characteristics are imparted to the rubber material. In particular, when the rubber content is 45% by mass or more and 62% by mass or less, a rubber material capable of imparting more excellent vibration damping property and vibration damping property can be obtained.

(Carbon black)
The rubber material according to the present embodiment preferably contains carbon black and preferably contains carbon black having a primary particle diameter of 26 nm or more. As such carbon blacks, high abrasion resistant (HAF: High Abrasion Finance) carbon black (primary particle size: 28 to 36 nm) and good processability channel (EPC: Easy Processing Channel) carbon black (primary particle size: 30 to). Hard carbon such as 35 nm); and conductive (XCF: eXtra Conductive Finance) carbon black (primary particle size: 26 to 30 nm), good extrudability (FEF: Fast Extruding Finance) carbon black (primary particle size: 39 to). 55nm), versatility (GPF: General Purpose Finance) carbon black (primary particle size: 49-60nm), high stress (HMF: High Modulus Finance) carbon black (primary particle size: 46-73nm), medium reinforcement (SRF) : Semi-Reinforcing Finance (Primary particle size: 70-96 nm), Fine-grained thermal decomposition (FT: Fine Thermal) Carbon black (Primary particle size: 180-200 nm), and Medium-grain thermal decomposition (MT: Medium Thermal) Examples thereof include soft carbon such as carbon black (primary particle size: 250 to 350 nm). These carbon blacks may be used alone or in combination of two or more. Among these, soft carbon is preferable as the carbon black, and SRF carbon black and MT carbon black are more preferable among the soft carbons. Commercially available products of carbon black include, for example, MT carbon black such as the product name "THERMAX (registered trademark) N990 LSR" (manufactured by Cancurve), the product name "HTC # S" (manufactured by Nittetsu Carbon Co., Ltd.) and the product name. Examples include SRF carbon black such as "Asahi # 50HG" (manufactured by Asahi Carbon Co., Ltd.) and HAF carbon black such as the trade name "Show Black N330" (manufactured by Showa Cabot Co., Ltd.).

The blending amount of carbon black is set so that the rubber content (rubber polymer fraction) is 30% by mass or more and 65% by mass or less. The blending amount of such carbon black is preferably more than 35 parts by mass and more preferably 50 parts by mass or more with respect to 100 parts by mass of rubber. Further, the blending amount of carbon black is preferably 250 parts by mass or less, and more preferably 200 parts by mass or less with respect to 100 parts by mass of rubber.

When the carbon black is MT carbon, the lower limit of the blending amount of the carbon black is based on 100 parts by mass of the rubber from the viewpoint of imparting an appropriate elastic modulus to the rubber material and improving the hamidashi characteristics when compressive stress is applied. , 50 parts by mass or more, more preferably 70 parts by mass or more, and further preferably 85 parts by mass or more. Further, the upper limit of the blending amount of carbon black is 220 parts by mass or less with respect to 100 parts by mass of rubber from the viewpoint of imparting appropriate hardness to the rubber material and improving vibration damping and vibration isolating properties. Is more preferable, and it is more preferably 200 parts by mass or less, and further preferably 180 parts by mass or less.

When the carbon black is SRF carbon, the lower limit of the blending amount of the carbon black is based on 100 parts by mass of the rubber from the viewpoint of imparting an appropriate elastic modulus to the rubber material and improving the hamidashi characteristics when compressive stress is applied. , 40 parts by mass or more, and more preferably 50 parts by mass or more. Further, the upper limit of the blending amount of carbon black is 120 parts by mass or less with respect to 100 parts by mass of rubber from the viewpoint of imparting appropriate hardness to the rubber material and improving vibration damping and vibration isolating properties. It is preferably 110 parts by mass or less, and more preferably 110 parts by mass or less.

The rubber material used to form the rubber layer of the gasket preferably contains a vulcanization agent and a vulcanization accelerator in order to provide a crosslinked structure in the rubber material. As the vulcanizing agent, for example, colloidal sulfur A (manufactured by Tsurumi Chemical Industry Co., Ltd.) and trade name "Barnock (registered trademark) R" (4,4'-dithiodimorpholine: manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) are commercially available. Goods can be mentioned. These vulcanizing agents may be used alone or in combination of two or more. The blending amount of the vulcanizing agent is preferably 0.1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of rubber, for example.

Various sulfur-containing vulcanization accelerators such as guanidine-based, aldehyde-amine-based, aldehyde-ammonia-based, thiazole-based, sulfenamide-based, thiourea-based, thiuram-based, dithiocarbamate-based and xanthate-based vulcanization accelerators. Is used. Among these, as the sulfur-containing vulcanization accelerator, tetramethylthiuram disulfide, tetrabenzylthiuram disulfide, N-cyclohexyl-2-benzothiadylsulfenamide and the like are preferable. These vulcanization accelerators may be used alone or in combination of two or more. The vulcanization accelerators include the trade name "Noxeller (registered trademark) TBZTD" (tetrabenzylthium disulfide: manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) and the trade name "Noxeller (registered trademark) CZ-P" (N-cyclohexyl). -2-Benzothiadylsulfenamide: manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) and other commercially available products can be mentioned. The blending amount of the vulcanization accelerator is preferably, for example, 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of rubber.

The rubber material is, if necessary, a plasticizer, an acid receiving agent such as zinc oxide, a processing aid such as stearic acid, an antiaging agent, and each auxiliary agent generally used in the rubber industry such as wax. May be contained.

Examples of the plasticizer include commercially available products such as the trade name "ADEKA SIZER (registered trademark) RS107" (azipic acid ether ester type: manufactured by ADEKA). As the acid receiving agent, for example, a commercially available product such as zinc oxide (manufactured by Shodo Chemical Industry Co., Ltd.) may be used. Examples of the anti-aging agent include commercially available products such as the trade name "Nocrack (registered trademark) 810-NA" (2,2,4-trimethyl-1,2-dihydroquinoline polymer: manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.). Can be mentioned. Examples of the processing aid include stearic acid, for example, a commercially available product such as the trade name “DTST” (manufactured by Miyoshi Oil & Fat Co., Ltd.). Examples of the wax include commercially available products such as the trade name "Santite (registered trademark) R" (normal paraffin wax: manufactured by Seiko Kagaku Co., Ltd.). Each of these auxiliaries may be used alone or in combination of two or more. The blending amount of each auxiliary agent is preferably, for example, 0.5 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of rubber.

Further, the rubber material may contain a filler such as calcium carbonate and silica, if necessary. As the calcium carbonate, various calcium carbonates such as heavy calcium carbonate and synthetic calcium carbonate can be used. Examples of calcium carbonate include commercially available products such as the trade name "Whiten (registered trademark) SB-red" (heavy calcium carbonate, manufactured by Bikita Powder Industry Co., Ltd.).

Examples of silica include dry silica produced by a thermal decomposition method of silicic acid halide or an organic silicon compound, a method of air-oxidizing vaporized silicon oxide (SiO) by heating and reducing silica sand, and the heat of sodium silicate. Amorphous silica such as wet silica manufactured by a decomposition method or the like can be used. Examples of commercially available silica products include the trade name "Nipsil (registered trademark) E-74P" (manufactured by Tosoh Silica Co., Ltd.). Each of these fillers may be used alone or in combination of two or more. The blending amount of each filler is preferably, for example, 2 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of rubber.

<Gasket>
The gasket according to the present embodiment includes a rubber layer containing the above-mentioned rubber material and a metal base material, and the rubber layer is provided on at least one surface of the metal base material. The rubber layer may be provided on one side of the metal base material, or may be provided on both sides. Since such a gasket is excellent in vibration damping property and vibration damping property even in a high temperature region required for a gasket for a housing, it can be used for an automobile housing component such as a compressor, an inverter, or a motor, for example. In particular, since it is possible to reduce noise and vibration such as motor start-up noise, when a gasket is applied to an automobile part, the vibration is reduced and the inside of the automobile becomes quieter, which can be expected to improve the riding comfort. In addition to applications other than automobiles, it is possible to prevent sounds and vibrations generated inside machines and devices from leaking to the outside. Further, it is possible to realize a gasket having a good gasket function such as a hammering characteristic.

(Rubber layer)
The rubber layer is formed, for example, by applying the above-mentioned vulcanized rubber material onto a metal substrate. The thickness of the rubber layer is appropriately set according to the use of the gasket, and is preferably 20 μm or more and 200 μm or less.

(Metal base material)
Examples of the material of the metal base material include iron, stainless steel, aluminum, magnesium, galvanized steel, copper and the like. As the iron, for example, cold rolled steel sheets (SPCC: Steel Plate Cold Commercial), high-strength steel sheets, mild steel sheets and the like are used. Further, as the stainless steel, for example, a ferritic stainless steel plate, a martensitic stainless steel, an austenitic stainless steel sheet, or the like can be used. Specific examples of stainless steel include SUS304, SUS301, SUS301H, and SUS430. As aluminum, an aluminum plate, an aluminum die-cast plate, or the like is used.

The metal base material is preferably surface-treated (surface-treated). The base treatment is not particularly limited, and a known base treatment can be used. When iron and stainless steel such as cold-rolled steel sheet, high-tensile steel sheet, and stainless steel sheet are used as the metal base material, the base treatment is, for example, a chemical conversion treatment using a chemical conversion treatment agent such as a zinc phosphate treatment or an iron phosphate treatment. A method and a plating method such as electrozinc plating and hot dip galvanizing are preferable. Examples of the chemical conversion treatment agent for a metal substrate include an organic chemical conversion treatment agent copper containing a silicone compound, a titanium compound, a zirconium compound and the like. Further, as the chemical conversion treatment agent, a chromium-free chemical conversion treatment agent that does not substantially contain chromium is preferable from the viewpoint of preventing environmental pollution.

The thickness of the metal base material is appropriately set according to the use of the gasket, and is preferably 100 μm or more and 2000 μm or less.

(glue)
The rubber layer and the metal substrate may be adhered to each other using an adhesive. As the adhesive, generally commercially available adhesives such as phenol resin, epoxy resin, polyurethane resin and silane are used. These adhesives can be appropriately selected depending on the use of the gasket. By using the adhesive, the adhesiveness between the metal base material and the rubber layer is improved.

As the phenol resin, for example, a novolak type phenol resin and a resol type phenol resin are used. As the novolak type phenol resin and the resol type phenol resin, one type may be used alone, or two or more types may be used in combination. Further, as the adhesive, those containing two types of phenol resins, a novolak type phenol resin and a resol type phenol resin, and unvulcanized nitrile rubber may be used.

Examples of the epoxy resin include bisphenol A type, cresol novolak type, biphenyl type, brominated epoxy resin and the like. These epoxy resins may be used alone or in combination of two or more. Among these epoxy resins, bisphenol A type epoxy resin and cresol novolac type epoxy resin are preferable from the viewpoint of easy availability of commercially available products and excellent heat resistance.

The various adhesives described above are used as a solution dissolved in an organic solvent. As the organic solvent, for example, ketones such as methyl ethyl ketone and methyl isobutyl ketone, aromatic hydrocarbons such as toluene and xylene, and the like are used. These organic solvents may be used alone or in combination of two or more.

<Manufacturing method of rubber material and gasket>
The rubber material and gasket according to this embodiment can be manufactured, for example, by the following method. As the rubber material, a predetermined nitrile rubber, carbon black, a vulcanizing agent, a vulcanization accelerator, various auxiliaries, a filler, etc. are blended as necessary, and the blending is an intermix, a kneader, a Banbury mixer, etc. Manufactured by kneading with a kneader or an open roll. The gasket is manufactured by applying a rubber material obtained via an adhesive layer onto a metal substrate that has been arbitrarily surface-treated, and then vulcanizing the rubber material under predetermined heating conditions to form a rubber layer. Ru. The rubber material is preferably applied so that the thickness of the rubber layer after application is 20 μm or more and 200 μm or less. Further, in the manufacture of the gasket, a resin-based or graphite-based coating agent may be applied onto the rubber layer.

The method for applying the rubber material to the metal substrate is not particularly limited as long as the rubber material can be applied onto the metal substrate. Examples of the coating method include a spray method, a dipping method, a roll coating method, a dispenser method and the like.

At the time of manufacturing the rubber material and applying it on the metal substrate, an organic solvent may be added to the rubber material to adjust the viscosity, if necessary. The organic solvent is not particularly limited as long as the viscosity of the rubber material can be adjusted to a desired viscosity. Examples of the organic solvent include methyl ethyl ketone, toluene, ethyl acetate and the like. These organic solvents may be used alone or in combination of two or more.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, but includes all aspects included in the concept of the present invention and claims, and varies within the scope of the present invention. Can be modified to.

Hereinafter, the present invention will be described in more detail based on examples. The present invention is not limited to the following examples.

(Example 1A) 100 parts by mass of nitrile rubber A (trade name "NANCAR (registered trademark) 3345", manufactured by Ssangyong Sangyo Co., Ltd.), carbon black A (MT carbon black: trade name "THERMAX (registered trademark) N990 LSR", 90 parts by mass of cancurve (manufactured by Cancurve), 5 parts by mass of zinc oxide (manufactured by Shodo Chemical Industry Co., Ltd.), 1 part by mass of stearic acid (trade name "DTST", manufactured by Miyoshi Oil & Fat Co., Ltd.), antiaging agent (2,2,4) -Trimethyl-1,2-dihydroquinoline polymer: trade name "Nocrack (registered trademark) 810-NA", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 2 parts by mass, vulcanizer A (colloidal sulfur A, Tsurumi Kagaku Kogyo Co., Ltd.) (Manufactured by) 1.5 parts by mass, vulcanizing agent B (4,4'-dithiodimorpholin: trade name "Barnock (registered trademark) R", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 1 part by mass, vulcanization accelerator A (Tetrabenzylthiuram disulfide: trade name "Noxeller (registered trademark) TBZTD", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 5 parts by mass, and vulcanization accelerator B (N-cyclohexyl-2-benzothiazyl sulphenamide: product) Name "Noxeller (registered trademark) CZ-P, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.") 4 parts by mass was kneaded with a kneader and an open roll to prepare a rubber material.

<Measurement of physical characteristics of rubber materials>
The obtained rubber material was pressurized at 170 ° C. for 8 minutes and vulcanized to prepare a sample of a rubber piece (width 4 mm × length 20 mm) having a thickness of 2 mm. The hardness of the obtained rubber piece was measured with a Type A durometer according to JIS K6253-3: 2012, and the 100% modulus value, tensile strength, and elongation were measured according to JIS K6251: 2017. The measurement results are shown in Table 1 below.

A gasket was produced using the obtained rubber material, and various performances of the produced gasket were evaluated.

<Vibration damping / vibration damping>
(1) Preparation of sample for measuring loss coefficient The surface of a cold-rolled steel sheet having a thickness of 400 μm was treated with zinc phosphate. Then, methyl ethyl ketone (MEK) in which a phenol resin (trade name "Sixson 715" manufactured by Rohm and Haas Japan Co., Ltd.) was dissolved was applied onto the surface-treated cold-rolled steel sheet, and then dried. The rubber material was then dissolved in MEK. After that, MEK in which the rubber material is melted is applied onto the cold-rolled steel sheet after applying the MEK solution containing phenol resin, and then the rubber material is vulcanized in an oven at 200 ° C. for 3 minutes for cold rolling. A rubber layer having a thickness of 120 μm was formed on a steel plate (metal base material). As a result, a gasket having a width of 17 mm and a length of 250 mm having a rubber layer on a metal substrate was produced. The gasket thus obtained was attached to a SUS301 plate having a thickness of 250 μm, a width of 17 mm, and a length of 250 mm via a cyanoacrylate-based adhesive to prepare a sample for measuring the loss coefficient. In addition, it was confirmed by a preliminary experiment in advance that the type of adhesive did not affect the value of the loss coefficient as long as the gasket could be attached to the SUS301 plate.

(2) Evaluation of anti-vibration and anti-vibration properties For the obtained sample, AS14PA5 (cantilever type) manufactured by Rion Co., Ltd. was used, and the half-value width method was used in accordance with JIS K7391: 2008, and the measurement temperature was 23 ± 2 ° C. The loss coefficient at room temperature was measured by the second-order resonance frequency in the range and the measurement range of 0 to 1 kHz. If the loss coefficient is 0.03 or more, it is judged that the vibration damping property and the vibration damping property are excellent and evaluated as "○". If the loss coefficient is less than 0.03, the vibration damping property and the vibration damping property are evaluated. It was judged to be inferior in sex and evaluated as "x". The evaluation results are shown in Table 1 below.

<Gasket function>
(1) Preparation of sample for compression test evaluation Phenol resin (trade name "Sixson 715" manufactured by Roam & Haas) was applied to MEK and methanol on a cold rolled steel sheet with a thickness of 400 μm surface-treated with zinc phosphate. An adhesive diluted with an organic solvent was applied and dried at room temperature. Next, the obtained rubber material was dissolved in an organic solvent and applied to a cold-rolled steel sheet coated with a phenol resin so that the thickness of the rubber layer was 120 μm, and then added in an oven at 200 ° C. for 3 minutes. Vulcanization was performed to prepare a sample for evaluation of the compression test of the gasket. Here, an anti-adhesion layer may be applied if necessary. The prepared sample for evaluation of the compression test was evaluated for the shaving property of the rubber layer as a gasket function by the following evaluation method.

(2) Evaluation of Hamidashi characteristics On the rubber layer of the casquette compression test evaluation sample, a donut-shaped convex metal fitting was placed at 100 ° C for 5 minutes, under condition A at a pressure of 150 MPa and at 150 ° C for 5 minutes. After pressing each under the condition B of the pressure of 150 MPa, the state of the rubber layer was evaluated based on the following criteria. In the following evaluation criteria, if the evaluations of Condition A and Condition B are 3 points or more, it is judged that the rubber layer is suppressed and evaluated as "○", and any evaluation is less than 3 points. If there is, it was judged that the suppression of the rubber layer was insufficient, and it was evaluated as "x". The evaluation results are shown in Table 1 below.
5 points: No metal exposure and almost no rubber flow.
4 points: There is no metal exposure and the rubber flow is small.
3 points: The rubber flow is not a little, but the metal is not exposed.
2 points: The rubber flow is large, but the metal exposure is small.
1 point: Both rubber flow and metal exposure are large.

(Example 2A)
A rubber material and a gasket were prepared in the same manner as in Example 1A except that the blending amount of carbon black A was 151 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Example 3A)
Except for the fact that the blending amount of carbon black A was 181 parts by mass, and 10 parts by mass of a plasticizer (adipinate ether ester type: trade name "ADEKA Sizer (registered trademark) RS107", manufactured by ADEKA) was used. A rubber material and a gasket were prepared in the same manner as in Example 1A, and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Example 4A)
Rubber material and gasket in the same manner as in Example 1A, except that carbon black B (SRF carbon black: trade name "HTC # S", manufactured by Nittetsu Carbon Co., Ltd.) was used instead of carbon black A by 65 parts by mass. Was prepared, and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Example 5A)
A rubber material and a gasket were prepared in the same manner as in Example 4A except that the blending amount of carbon black B was 104 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Example 6A)
The rubber material and gasket were used in the same manner as in Example 1A, except that 58 parts by mass of carbon black C (SRF carbon black: trade name "Asahi # 50HG", manufactured by Asahi Carbon Co., Ltd.) was used instead of carbon black A. It was prepared and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Example 7A)
The rubber material and gasket were used in the same manner as in Example 1A, except that carbon black D (HAF carbon black: trade name “Show Black N330”, manufactured by Showa Cabot Corporation) was used instead of carbon black A by 46 parts by mass. It was prepared and the above measurement and evaluation were performed. The results are shown in Table 1 below.

(Comparative Example 1A)
A rubber material and a gasket were prepared in the same manner as in Example 1A except that the blending amount of carbon black A was 45 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 2 below.

(Comparative Example 2A)
A rubber material and a gasket were prepared in the same manner as in Example 4A except that the blending amount of carbon black B was 31 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 2 below.

(Comparative Example 3A)
A rubber material and a gasket were prepared in the same manner as in Example 6A except that the blending amount of carbon black C was 30 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 2 below.

(Comparative Example 4A)
A rubber material and a gasket were prepared in the same manner as in Example 6A except that the blending amount of carbon black C was 125 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 2 below.

(Comparative Example 5A)
A rubber material and a gasket were prepared in the same manner as in Example 1A except that the blending amount of carbon black A was 230 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 2 below.

(Example 1B)
Nitrile rubber A (trade name "NANCAR (registered trademark) 3345", manufactured by Ssangyong Sangyo Co., Ltd.) 100 parts by mass, carbon black A (MT carbon black: trade name "THERMAX (registered trademark) N990 LSR", manufactured by Cancurve) 90 parts by mass, zinc oxide (manufactured by Shodo Chemical Industry Co., Ltd.) 5 parts by mass, stearic acid (trade name "DTST", manufactured by Miyoshi Oil & Fat Co., Ltd.) 1 part by mass, antiaging agent (2,2,4-trimethyl-1, 2-Dihydroquinoline polymer: trade name "Nocrack (registered trademark) 810-NA", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 2 parts by mass, vulcanizer A (colloidal sulfur A, manufactured by Tsurumi Kagaku Kogyo Co., Ltd.) 1.5 By mass, vulcanizing agent B (4,4'-dithiodimorpholin: trade name "Barnock (registered trademark) R", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 1 part by mass, vulcanization accelerator A (tetrabenzylthiuram disulfide) : Product name "Noxeller (registered trademark) TBZTD", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.) 5 parts by mass, and vulcanization accelerator B (N-cyclohexyl-2-benzothiazyl sulphenamide): Product name "Noxeller (registered) Trademark) CZ-P, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd. ") 4 parts by mass were kneaded with a kneader and an open roll to prepare a rubber material.

<Measurement of physical characteristics of rubber materials>
A rubber piece sample was prepared in the same manner as in Example 1A. The hardness of the obtained rubber piece was measured with a Type A durometer according to JIS K6253-3: 2012, and the 100% modulus value, tensile strength, and elongation were measured according to JIS K6251: 2017. The measurement results are shown in Table 3 below.

A gasket was produced using the obtained rubber material, and various performances of the produced gasket were evaluated.

<Vibration damping / vibration damping>
(1) Preparation of sample for loss coefficient measurement A sample for loss coefficient measurement was prepared in the same manner as in Example 1A above. In addition, it was confirmed by a preliminary experiment in advance that the type of adhesive did not affect the value of the loss coefficient as long as the gasket could be attached to the SUS301 plate.

(2) Evaluation of anti-vibration and anti-vibration properties For the obtained sample, AS14PA5 (cantilever type) manufactured by Rion Co., Ltd. was used, and the half-value width method was used in accordance with JIS K7391: 2008, and the measurement temperature was 23 ± 2 ° C. The loss coefficient at room temperature was measured by the second-order resonance frequency in the range and the measurement range of 0 to 1 kHz. In addition, the loss coefficient at high temperature was also measured by the secondary resonance frequency in the measurement temperature of 50 ° C. and 70 ° C. and the measurement range of 0 to 20 kHz. If the loss coefficient at 50 ° C. and 70 ° C. is 0.015 or more, it is judged that the vibration damping property and the vibration damping property are excellent and evaluated as "○", and one of the loss coefficients is 0. If it is less than .015, it is judged that the vibration damping property and the vibration damping property are inferior, and the evaluation is "x". The evaluation results are shown in Table 3 below.

<Gasket function>
A sample for evaluation of the compression test of the gasket was prepared by the same method as in Example 1A. Here, an anti-adhesion layer may be applied if necessary. With respect to the prepared sample for evaluation of the compression test, the hamidashi property of the rubber layer was evaluated as a gasket function by the same evaluation method as in Example 1A. The evaluation results are shown in Table 3 below.

(Example 2B)
A rubber material and a gasket were prepared in the same manner as in Example 1B except that 100 parts by mass of nitrile rubber B (trade name "N230S", manufactured by JSR Corporation) was used instead of nitrile rubber A, and the above measurement was performed. And evaluation was performed. The results are shown in Table 3 below.

(Example 3B)
A rubber material and a gasket were prepared in the same manner as in Example 1B except that 100 parts by mass of nitrile rubber C (trade name "N220S", manufactured by JSR Corporation) was used instead of nitrile rubber A, and the above measurement was performed. And evaluation was performed. The results are shown in Table 3 below.

(Example 4B)
Instead of nitrile rubber A, 100 parts by mass of nitrile rubber D (trade name "Nipol (registered trademark) DN003", manufactured by Nippon Zeon Co., Ltd.) was used, and the amount of carbon black A was 60 parts by mass. A rubber material and a gasket were prepared in the same manner as in Example 1B, and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Example 5B)
A rubber material and a gasket were prepared in the same manner as in Example 1B except that the blending amount of carbon black A was 151 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Example 6B)
Rubber material and gasket in the same manner as in Example 1B, except that carbon black B (SRF carbon black: trade name "HTC # S", manufactured by Nittetsu Carbon Co., Ltd.) was used instead of carbon black A by 65 parts by mass. Was prepared, and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Example 7B)
A rubber material and a gasket were prepared in the same manner as in Example 6B except that the blending amount of carbon black B was 104 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Example 8B)
The rubber material and gasket were used in the same manner as in Example 1B except that 58 parts by mass of carbon black C (SRF carbon black: trade name "Asahi # 50HG", manufactured by Asahi Carbon Co., Ltd.) was used instead of carbon black A. It was prepared and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Example 9B)
A rubber material and a gasket were prepared in the same manner as in Example 8B except that the blending amount of carbon black C was 90 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 3 below.

(Comparative Example 1B)
A rubber material and a gasket were prepared in the same manner as in Example 1B except that 100 parts by mass of nitrile rubber E (trade name "N240S", manufactured by JSR Corporation) was used instead of nitrile rubber A, and the above measurement was performed. And evaluation was performed. The results are shown in Table 4 below.

(Comparative Example 2B)
A rubber material and a gasket were prepared in the same manner as in Example 1B except that the blending amount of carbon black A was 45 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 4 below.

(Comparative Example 3B)
A rubber material and a gasket were prepared in the same manner as in Example 6B except that the blending amount of carbon black B was 31 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 4 below.

(Comparative Example 4B)
A rubber material and a gasket were prepared in the same manner as in Example 8B except that the blending amount of carbon black C was 30 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 4 below.

(Comparative Example 5B)
A rubber material and a gasket were prepared in the same manner as in Example 8B except that the blending amount of carbon black C was 125 parts by mass, and the above measurement and evaluation were performed. The results are shown in Table 4 below.

The compounding materials of each component in Tables 1 to 4 above are as follows.
Nitrile rubber A: Medium and high nitrile (acrylonitrile content 33%, trade name "NANCAR (registered trademark) 3345", manufactured by Ssangyong Sangyo Co., Ltd.)
Nitrile rubber B: Medium and high nitrile (acrylonitrile content 35%, trade name "N230S", manufactured by JSR Corporation)
Nitrile rubber C: High nitrile (acrylonitrile content 41.5%, trade name "N230S", manufactured by JSR Corporation)
Nitrile rubber D: Extremely high nitrile (acrylonitrile content 50%, trade name "Nipol (registered trademark) DN003", manufactured by Zeon Corporation)
Nitrile rubber E: Medium nitrile (acrylonitrile content 26%, trade name "N240S", manufactured by JSR Corporation)
Carbon Black A: MT Carbon Black (Product name "THERMAX (registered trademark) N990 LSR" manufactured by Cancurve)
Carbon Black B: SRF Carbon Black (trade name "HTC # S", manufactured by Nittetsu Carbon Co., Ltd.)
Carbon Black C: SRF Carbon Black (Product name "Asahi # 50HG", manufactured by Asahi Carbon Co., Ltd.)
Carbon Black D: HAF Carbon Black (Product name "Show Black N330", manufactured by Showa Cabot)
Plasticizer: Adipic acid ether ester type (trade name "ADEKA Sizer (registered trademark) RS107", manufactured by ADEKA)
Zinc oxide (manufactured by Shodo Chemical Industry Co., Ltd.)
Stearic acid: Brand name "DTST" (manufactured by Miyoshi Oil & Fat Co., Ltd.)
Anti-aging agent: 2,2,4-trimethyl-1,2-dihydroquinoline polymer (trade name "Nocrack (registered trademark) 810-NA", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
Vulcanizing agent A: Colloidal sulfur A (manufactured by Tsurumi Chemical Industry Co., Ltd.)
Vulcanizing agent B: 4,4'-dithiodimorpholine (trade name "Barnock (registered trademark) R", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
Vulcanization accelerator A: Tetrabenzyl thiuram disulfide (trade name "Noxeller (registered trademark) TBZTD", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
Vulcanization accelerator B: N-cyclohexyl-2-benzothiadylsulfenamide (trade name "Noxeller (registered trademark) CZ-P", manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
The blending amount of each of the above components in Tables 1 to 4 represents "parts by mass".

As shown in Table 1, the gasket is provided with a rubber layer containing a rubber material having a 100% modulus value of 5.0 MPa or more and a type A durometer hardness of 90 or less to provide vibration damping and resistance. Gaskets having excellent vibration characteristics and a good gasket function were obtained (Examples 1A to 7A). In particular, when the rubber content (rubber polymer fraction) was 45% by mass or more and 62% by mass or less, it was excellent in vibration damping property and vibration damping property (Examples 1A, 4A, 6A and 7A).

On the other hand, as shown in Table 2, when the 100% modulus value of the rubber material is less than 5.0 MPa, the evaluation of the Hamidashi characteristic is less than 3, and a sufficient gasket function could not be achieved (Comparative Examples 1A to 1A). 3A). Further, when the type A durometer hardness of the rubber material exceeded 90, the loss coefficient was less than 0.03 in each case, and the vibration damping property and the vibration damping property were inferior (Comparative Examples 4A to 5A).

Further, as shown in Table 3, nitrile rubber containing 30% by mass or more of acrylonitrile is used as the rubber material, the 100% modulus value of the rubber material is 5.0 MPa or more, and the type A durometer hardness is When it was 90 or less, a gasket having a high loss coefficient even at a high temperature, excellent vibration damping property and vibration isolating property, and a good gasket function was obtained (Examples 1B to 9B). In particular, when a nitrile rubber containing 36% by mass or more of acrylonitrile was used, it showed a higher loss coefficient and was excellent in vibration damping and vibration damping properties (Examples 3B and 4B). Further, when the rubber content (rubber polymer fraction) was 45% by mass or more and 62% by mass or less, the loss coefficient at room temperature was high, and the vibration damping property and the vibration damping property were excellent (as in Table 1). Examples 1B-4B, 6B and 8B-9B).

On the other hand, as shown in Table 4, when a nitrile rubber having an acrylic nitrile content of less than 30% by mass is used, the loss coefficient at high temperature is less than 0.015, and the vibration damping property and the vibration damping property are inferior. (Comparative Example 1B). Further, even if a nitrile rubber containing 30% by mass or more of acrylonitrile is used, when the 100% modulus value of the rubber material is less than 5.0 MPa, the evaluation of the Hamidashi property is less than 3, and a sufficient gasket function is achieved. It could not be done (Comparative Examples 2B-4B). Further, when the type A durometer hardness of the rubber material exceeds 90, the loss coefficient at high temperature is less than 0.015, and the vibration damping property and the vibration damping property are inferior (Comparative Example 5B).

From the above results, in the rubber material containing nitrile rubber containing 30% by mass or more of acrylic nitrile and carbon black, the 100% modulus value of the rubber material is 5.0 MPa or more, and the type A durometer hardness is 90. By the following, it is possible to provide a rubber material suitable for producing a gasket having excellent vibration damping property and vibration isolating property, and further having a good gasket function such as a hammering property. A gasket provided with a rubber layer containing such a rubber material can exhibit excellent vibration damping and vibration damping properties, and is particularly suitable for use as a gasket for a housing of a compressor, an inverter, a motor, or the like. ..

Claims (5)

Contains rubber and carbon black,
The rubber is a nitrile rubber containing 30% by mass or more of acrylonitrile.
Gasket characterized in that the 100% modulus value according to JIS K6251: 2017 is 5.0 MPa or more, and the type A durometer hardness measured according to JIS K6253-3: 2012 is 90 or less. For rubber material. The rubber material according to claim 1, wherein the content of rubber contained in the rubber material is 30% by mass or more and 65% by mass or less. The rubber material according to claim 1 or 2, wherein the carbon black has a primary particle diameter of 26 nm or more. The rubber material according to any one of claims 1 to 3, which contains more than 35 parts by mass of carbon black with respect to 100 parts by mass of the rubber. A rubber layer containing the rubber material according to any one of claims 1 to 4 and a metal base material are provided.
A gasket in which the rubber layer is provided on at least one surface of the metal substrate.