JPS62246679A - Reinforcing rubber hose - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rubber hose in which an inner tube layer, an intermediate reinforcing layer, and an outer tube layer are formed substantially simultaneously at the same site. It is particularly suitable for automotive oil hoses such as vacuum pump hoses, engine oil cooler hoses, and torque converter hoses, which require oil resistance, heat resistance, and even weather resistance.

<Prior art> In this specification, "part", "%", "ph
All r J values are in units of weight.

Recent automotive oil hoses are designed to improve engine performance,
In addition to oil resistance, strict heat resistance is now required due to exhaust gas regulations. As a rubber material that satisfies this condition,
Polymers described in JP-A No. 55-726,
That is, a vinyl acetate-based copolymer is produced by copolymerizing the three components of ethylene, vinyl acetate, and acrylic ester, and adding 10 parts or less of glycidyl acrylates and glycidyl ethers as a crosslinking comonomer to 100 parts of the total amount of the three components. Focusing on polymers, the applicant of the present application has developed a method for manufacturing a rubber hose in which an inner tube layer 1, an intermediate reinforcing layer 2, and an outer tube layer 3 are formed almost simultaneously at the same site, as shown in Figures 1 and 2. I tried to do it by method (Special Publication No. 59-39300/Sho 60-
(See Publication No. 50132, etc.).

That is, the inner tube extruder 14 and the outer tube extruder 15 are arranged with their axes perpendicular to each other so that the inner tube die 11, the intermediate die 12, and the outer tube die 13 are close to each other, and each extrusion port is located at the same location. The blade machine 1 is installed so that the reinforcing yarn F can be introduced from the gap between the inner tube die 11 and the intermediate die 12 and driven onto the inner tube layer 1.
6 (or spiral machine) is disposed coaxially with the inner tube extruder 14. Here, the torpedo 17 that regulates the inner diameter of the inner tube layer 1 slightly protrudes from the tip surface of the inner tube die 11.

In addition, H in the figure is a reinforced rubber hose.

<Problems to be Solved by the Invention> When the inner tube layer is extruded using a device having the above configuration using a rubber compound containing the vinyl acetate copolymer as a polymer,
Means for solving the problem that the die swell is large and hinders the smooth formation of the reinforcing layer and the outer tube layer> In order to solve the above problem, the present inventors have made extensive efforts in terms of materials. As a result of our efforts in development, we came up with a reinforced rubber hose with the following configuration.

In a reinforced rubber hose manufactured by forming an inner tube layer, an intermediate reinforcing layer, and an outer tube layer almost simultaneously at the same site, the inner tube layer consists of: , the copolymerization of specific amounts of glycidyl acrylates and glycidyl ethers as crosslinking comonomers; It is characterized by being composed of sulfur.

Detailed explanation of the configuration The present invention will be explained in detail below.

The reinforced rubber hose consists of an inner tube layer 1, an intermediate reinforcing layer 2, and an outer tube layer 3, and each of these layers is formed almost simultaneously using the same material (the circumferential surface of the tip of the torpedo 17) by the above-mentioned manufacturing apparatus. Ru.

Here, the present invention is characterized in that the inner tube layer 1 is made of a vulcanized product of a rubber compound having the following specific configuration (a) Ho! J-mer, ethylene fistyl vinyl acetate O acrylic acid ester as three components, glycidyl acrylates and glycidyl ethers as crosslinking comonomers, each 0.5 to 2.0 parts per 100 parts of the total amount of the three components, 0.1~0
．． A copolymer is obtained by adding 5 parts of the mixture.

Here, as described in the above-mentioned publication, the copolymerization ratio of ethylene to vinyl acetate is equal to or less than the equivalent weight ratio, and the copolymerization ratio in the total amount of the three components of the acrylic ester is 90% or less. Examples of acrylic esters include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, inbutyl acrylate, n-hexyl acrylate, n-octyl acrylate, and 2-ethyl-hexyl acrylate. , particularly n-butyl acrylate.

In addition, as glycidyl acrylates, glycidyl acrylate, glycidyl methacrylate (rGM
Examples of the glycidyl ethers include allyl glycidyl ether (hereinafter abbreviated as rAGEJ), vinyl glycidyl ether, metaallyl glycidyl ether, and the like. If glycidyl acrylates and glycidyl ethers are used in combination, the former alone will not provide a die swell reduction effect, and the latter alone will cause problems with crosstalk. The mixing ratio of both is an allowable range determined by taking into consideration both die swell and kneading properties.

(b) Carbon black with an average particle size of 30 to 55 mL
L, DBP oil absorption amount of 120 ml/100 g or more. If the average particle diameter is less than 30 ml, the effect of reducing die swell cannot be obtained, and if it exceeds 55 ml, it is difficult to obtain sufficient strength for the vulcanized rubber. DBP oil absorption amount is 120 ml/1
If it is less than 00g, the die swell reduction effect cannot be obtained. Carbon black that meets these conditions is
F E F (Fast Extruding Furn
ance), MAF (Medium Abr
ation Furnance), etc. The blending amount of this carbon black is the usual blending amount (50N100ph
r) is fine.

(C) In addition to the above polymer and carbon black, the rubber compound according to the present invention includes a vulcanizing agent, a vulcanization accelerator, a lubricant,
Processing aids, anti-aging agents, fillers, plasticizers and the like are appropriately added. Examples of the lubricant include stearic acid and its metal salts.

As the reinforcing yarn F of the intermediate reinforcing layer 2, synthetic fibers such as polyamide, rayon, polyester, and vinylon are used.

The rubber material of the outer tube layer 3 may be the same as the rubber material of the inner tube layer 1, but since there is no problem in manufacturing the rubber hose even if die swell occurs, the rubber material of the outer tube layer 3 may be a rubber material made of the same type of polymer, Alternatively, rubber materials such as NBR, CR, and EPDM may be used.

<Actions and Effects of the Invention> As described above, the reinforced rubber hose of the present invention has an inner tube layer of
The polymer is copolymerized by adding specific amounts of glycidyl acrylates and glycidyl ethers as crosslinking comonomers to the three components of ethylene, vinyl acetate, and acrylic ester, and carbon black is copolymerized with specific average particles. Although the reason is unknown, when the inner tube layer, intermediate reinforcing layer, and outer tube layer are simultaneously formed at the same site, the inner tube layer, the intermediate reinforcing layer, and the outer tube layer are formed simultaneously at the same site. , as shown in the examples below,
The die swell of the inner tube layer is small, so the reinforced rubber hose can be manufactured with good productivity without hindering the smooth formation of the intermediate reinforcing layer and the outer V layer.

<Examples> Examples conducted to confirm the effects of the present invention will be described below.

The rubber compounds of each example and comparative example contained polymers of 7% ethylene, 14% vinyl acetate, n
- Based on the three components of butyl acrylate 79%, the mixing ratio of crosslinking comonomers GMA and AGE is
These were obtained by copolymerization with varying amounts as shown in the table.

Using each rubber compound, under the conditions shown in Table 1, an outer diameter of 12
A tube with an inner diameter of 10 mm and an inner diameter of 10 mm was extruded, and the die swell at that time was determined by the formula. Moreover, the kneading property was determined by roll workability. Furthermore, the normal physical properties are JISK-6301
Measured according to.

From the results shown in Table 1, it can be seen that the rubber material used in the present invention has a small die swell and good crosstalk properties.

As shown in Comparative Example 4116, the die swell is not reduced when using only GMA, but even when MAF and FEF are used as carbon black, as shown in Comparative Example 2, even when GMA and AGE meet the requirements of the present invention, the die swell is Black is HAF
Therefore, it is not possible to obtain a sufficient die swell reduction effect.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view of an apparatus used for manufacturing the reinforced rubber hose of the present invention, and FIG. 2 is an enlarged half-sectional view of the main part of the section (■) in FIG. L...Inner tube layer, 2...Intermediate reinforcing layer, 3...Outer tube layer, H...Reinforced rubber hose. Patent applicant

Claims (1)

[Scope of Claims] A reinforced rubber hose manufactured by forming an inner tube layer, an intermediate reinforcing layer, and an outer tube layer substantially simultaneously at the same site, wherein the inner tube layer comprises: In addition to the three components of vinyl acrylic acid ester, glycidyl acrylates and glycidyl ethers are added as crosslinking comonomers at 0.5 to 2 parts by weight per 100 parts by weight of the three components in total.
．． (b) carbon black with an average particle diameter of 30 to 55 mμ;
, having a DBP oil absorption of 120 ml/100 g or more, and being made of a vulcanized product of a rubber compound.