JPH0764958B2 - Vulcanized rubber sealing material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vulcanized rubber seal material. For more details,
The present invention relates to an oil-containing vulcanized rubber sealing material.

[Conventional technology]

It has been conventionally performed that liquid oil continuously exudes to the surface of a vulcanized rubber molded product, and imparts sealing properties, lubricity, wear resistance, and the like thereto.

Such oil-containing rubber is obtained by a method of mixing a liquid oil during kneading, a method of immersing a vulcanized molded article in the liquid oil, or the like, but any of them has the following drawbacks.

That is, in the former method, kneading is generally difficult, and even if kneading is possible, only a fixed amount of liquid oil can be mixed, and liquid oil cannot be leached from the vulcanization molding surface at a constant rate. In the latter method, the liquid oil cannot be impregnated unless the vulcanized molded product is swollen by immersion, and even if it is possible, it is difficult to exude the liquid oil onto the surface of the molded product at a constant rate. is there.

[Problems to be solved by the invention]

The present inventors, unlike the method for producing an oil-containing rubber by such a conventional method, carry out various investigations for those capable of leaching liquid oil at a constant rate on the surface of a vulcanized rubber sealing material without causing such a defect. As a result of stacking, it has been found that such problems can be effectively solved by impregnating a liquid oil into an inorganic porous material and incorporating it into a vulcanized rubber sealing material.

[Means for solving problems]

Therefore, the present invention relates to an oil-containing vulcanized rubber seal material, which has an average particle diameter of 1 to 1000 μm and a pore diameter of 3
~ 8000Å, pore volume 0.2 ~ 2.2ml / g SiO ₂ microporous beads or average particle size 1 ~ 10μm, oil absorption 100 ~ 200
Kinematic viscosity of diatomaceous earth (ml / 100g, bulk density 0.4-0.8g / cc) (4
The oil-containing inorganic porous material impregnated with a liquid oil whose temperature is 0 to 1000 cst is contained.

Such an oil-containing vulcanized rubber sealing material is a method of applying a liquid oil impregnation method such as dipping or spraying in a vulcanized molded product of a mixture of rubber and an inorganic porous material, or a mixture of rubber and a liquid oil-impregnated inorganic porous material. Is obtained by vulcanization molding, and in these cases, the kneading of the rubber and the (liquid oil-impregnated) inorganic porous material is also carried out smoothly.

As rubber, SBR, NBR, butyl rubber, hydrin rubber,
Various synthetic rubbers such as EPDM, chloroprene rubber, acrylic rubber, fluororubber or natural rubber are used.

As the inorganic porous material, for example, SiO ₂ microporous beads and diatomaceous earth are used. As the SiO ₂ -based microporous beads, spherical or amorphous particles having an average particle diameter of about 1 to 1000 μm, a pore diameter of about 3 to 8000 Å, and a pore volume of 0.2 to 2.2 ml / g are used, and commercially available products such as Fuji Devison Chemical Products such as micro beads, silica gel 3A, 4B, 5D or the company's product Syloid 63-978 are used as they are. Also, for diatomaceous earth, the average particle size is about 1 to 10μ.
m, oil absorption about 100-200ml / 100g, bulk density about 0.4-0.8g / cc
What is used.

As the liquid oil, for example, silicone oil, fluorine oil, brake oil, engine oil, transmission oil, refrigerator oil, gear oil, antifreeze, ether-based or ester-based plasticizer, kinematic viscosity (40 ° C.) of about 1 to 1000 Cst, Alternatively, those having a boiling point of about 25 to 500 ° C, preferably about 200 to 500 ° C are used.

These liquid oils are impregnated into the inorganic porous material before or after vulcanization molding, and the impregnated liquid oil leaches out at a constant rate from the surface of the vulcanized rubber sealing material.

〔The invention's effect〕

The vulcanized rubber seal material according to the present invention improves the lubricity, abrasion resistance, sealability, etc. without substantially impairing the original properties of the rubber as a result of liquid oil leaching from the surface at a constant rate. Let Therefore, this vulcanized rubber sealing material can be effectively used for applications such as oil seals, dynamically used O-rings, and packings.

〔Example〕

 Next, the present invention will be described with reference to examples.

Example 1 100 parts of fluororubber (Viton E60C manufactured by DuPont; crosslinker-containing type) (weight, the same applies below), SiO ₂ -based microporous beads (Fuji Devison Chemical Product Cyloid 800;
Pore volume 1.6ml / g, Pore diameter 120Å, average particle size 3.5μm) 2
0 part, 6 parts calcium hydroxide and 3 parts magnesium oxide
Parts were mixed with 10-inch open tyrol, and compression molding was performed at 180 ° C for 6 minutes also as primary crosslinking to prepare a sheet of 200 x 120 x 2 mm, and then secondary crosslinking was performed in an oven at 200 ° C for 24 hours. .

The obtained sheet-like body was immersed in various oils under conditions of 100 ° C. and 24 hours and then pulled up.
Adhesiveness (on top of rubber sheet and brass plate, put a load of 500g on it, leave it in an atmosphere of 120 ° C for 70 hours, and then measure the force required to peel them off) and various physical properties,
The results shown in Table 1 below were obtained.

[Impregnating oil] A: Dimethyl silicone type silicone oil Kinematic viscosity 200Cst (40 ° C) B: Naphthene type refrigerator oil Kinematic viscosity 40Cst (40 ° C) C: Engine oil (SAE100W-30) Kinematic viscosity 50Cst (40 ° C) D: Fluorine Alcohol-based Fluorine Oil Kinematic Viscosity 25Cst (40 ° C) Example 2 100 parts of acrylic rubber (NOK product A-1095) and a predetermined amount of auto transmission oil (kinematic viscosity 50Cst, 40 ° C) of 50 parts diatomaceous earth ( Central silica product Silica 6-B;
Average particle size 2-4μm, bulk density 0.14g / cc, linseed oil absorption
Oil-containing diatomaceous earth impregnated with 125%), 1 part of trizinetrithiol and 4.5 parts of sodium stearate are mixed with a 10-inch open roll, and also serve as primary crosslinking at 180 ° C.
After compression molding for 10 minutes to prepare a sheet-like body of 200 × 120 × 2 mm, secondary cross-linking was performed in an oven at 150 ° C. for 5 hours.

Various physical properties and Taber abrasion (a value obtained by dividing the weight reduction value after 100 rotations by the specific gravity) using the H-18 magnet were measured for the obtained sheet-shaped body, and the results shown in Table 2 below were measured. Obtained. No. 5 is a reference example with a different filler, and 50 parts of FEF carbon black and 25 parts of auto transmission oil were used instead of the oil-containing diatomaceous earth of No. 2.

Claims (1)

[Claims] 1. An average particle size of 1 to 1000 μm, a pore size of 3 to 8000Å,
SiO ₂ microporous beads with a pore volume of 0.2 to 2.2 ml / g or average particle size of 1 to 10 μm, oil absorption of 100 to 200 ml / 100 g, bulk density
0.4 to 0.8 / cc diatomaceous earth with a kinematic viscosity of 1 to 1000C (40 ° C)
A vulcanized rubber sealing material containing an oil-containing inorganic porous material impregnated with st liquid oil.