JPH07103948B2 - Rubber hose for vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rubber hose for vehicles used in, for example, fuel systems and hydraulic systems of automobiles, and in particular, a flame-retardant acrylic rubber composition on the outer peripheral portion of the hose. The present invention relates to a rubber hose for a vehicle having a protector layer.

<Prior Art> In recent years, rubber hoses used for fuel systems and hydraulic systems of internal combustion engines tend to be required to have higher flame retardancy. For this reason, research and development of flame-retardant rubber hoses are underway.

For this reason, when a rubber hose such as a fuel system is placed near the high temperature part of the engine in the engine room of a car, a metal tube, a metal plate, etc. is fitted to the outer peripheral part to protect the rubber hose from high temperatures. I'm using it.

<Problems to be Solved by the Invention> However, when a metal tube or a metal plate is used for protection of a rubber hose, there is a problem that the weight increases and the degree of freedom in design is small.

It is an object of the present invention to provide a vehicle rubber hose having a protector layer having sufficient flame retardancy and flexibility.

<Means for Solving the Problems> The vehicle rubber hose of the present invention has been made to solve the above problems. In a vehicle rubber hose having a protector layer on an outer peripheral portion thereof, the protector layer is an acrylic rubber.
It is characterized by being formed of a flame-retardant acrylic rubber composition in which 35 to 60 parts by weight of carbon black and 5 to 30 parts by weight of expandable graphite are mixed with 100 parts by weight.

Each component which comprises the said flame-retardant acrylic rubber composition is demonstrated below.

As the acrylic rubber, those having vinyl siloxane as a cross-linking group, those having an epoxy group, and the like are used, and those having vinyl siloxane are preferable in terms of flame retardancy.

As the carbon black, HAF carbon black, MAF carbon black, FEF carbon black, etc. can be used. The blending amount of this carbon black is 35 to 60 parts by weight with respect to 100 parts by weight of acrylic rubber. When the amount of the carbon black is less than 35 parts by weight, the kneading processability is poor, and when it exceeds 60 parts by weight, the vulcanized rubber has a high hardness and loses flexibility.

Expandable ferrite (expanded graphite) is, for example, natural scaly graphite treated with sulfuric acid and an oxidizing agent, washed with water, dehydrated,
It is manufactured through processes such as drying.
What is known in 1311 can be used. Expandable Graphite heats up rapidly (800-1000 ℃)
Then, it expands up to 100 to 300 times in the C-axis direction, and exhibits excellent heat insulation. The amount of this expandable graphite is 5 to 3 per 100 parts by weight of acrylic rubber.
0 parts by weight. If the compounding amount of expandable graphite is less than 5 parts by weight, the flame retardancy is insufficient, and if it exceeds 30 parts by weight, the roll adhesiveness becomes large and the kneading processability deteriorates.

<Effects of the Invention> In the rubber hose for vehicle of the present invention, the flame-retardant acrylic rubber composition constituting the protector layer on the outer peripheral portion of the hose is blended with a specific amount of carbon black and expandable graphite in the acrylic rubber. Excellent flame retardancy is obtained by expanding the expandable graphite. Further, this acrylic rubber composition has good kneading processability, is easy to process into a protector layer of a rubber hose, and does not generate a halogen-based gas during combustion.

<Examples> Hereinafter, the present invention will be described in detail with reference to Examples.

FIG. 1 shows a perspective view of a vehicle rubber hose as an embodiment of the present invention.

This rubber hose is provided on the inner pipe layer 1, the reinforcing yarn layer 2 wound around the outer periphery of the inner pipe layer 1, the outer pipe layer 3 arranged on the outer periphery of the reinforcing yarn layer 2, and the outer periphery of the outer pipe layer 3. The protector layer 4 is provided.

For example, NBR rubber is used for the inner tube layer 1, nylon yarn is used for the reinforcing thread layer 2, and CR rubber is used for the outer tube layer 3. For the protector layer 4, a flame-retardant acrylic rubber composition having the composition shown in Table 1 is used.

Each rubber hose material is supplied to, for example, a plurality of extruders arranged so as to sandwich a reinforcing yarn layer forming device such as a spiral device, and is extruded from the extruders to integrally extrude the rubber hose.

The protector layer 4 of the flame-retardant acrylic rubber composition may be formed on the outer peripheral portion of the single-layer rubber hose instead of the multi-layer reinforced rubber hose. Further, the protector layer 4 may be formed separately from the rubber hose body and then fitted to the outer peripheral portion of the rubber hose body later.

Regarding the blending of the flame-retardant acrylic rubber composition constituting the protector layer, kneading processability, normal state physical properties and flammability were evaluated as shown in Table 1.

As the expandable graphite, expandable craftite 9960 (manufactured by Nippon Kasei Co., Ltd.) was used. The vulcanization conditions of the test piece were 150 ° C. × 10 minutes. Normal physical properties were evaluated based on JIS K6301 and flammability based on FMVSS302. Regarding the flammability, those that self-extinguish within a burning time of 60 seconds or a burning length of 5 cm were designated as flame-retardant.

As shown in Table 1, the acrylic rubber composition of each Example
It has good kneading processability and normal physical properties, has flame retardancy, and does not generate halogen gas during combustion. When the flame retardant is not blended (Comparative Example 1) and when the blended amount of the hydrated inorganic material is small (Comparative Example 2), flame retardancy cannot be obtained. When a large amount of a hydrated inorganic substance is added to obtain flame retardancy (Comparative Example 3), the kneading process becomes difficult. When chlorinated paraffin and antimony trioxide are used together as a flame retardant (Comparative Example 4), the kneading processability is slightly deteriorated and a halogen-based gas is generated during combustion.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a rubber hose for a vehicle according to an embodiment of the present invention. 4 ... protector layer.

Claims (1)

[Claims] 1. A rubber hose for a vehicle having a protector layer on an outer peripheral portion, wherein the protector layer is composed of 35 to 60 parts by weight of carbon black and 5 to 30 parts by weight of expandable graphite with respect to 100 parts by weight of acrylic rubber. A rubber hose for a vehicle, comprising a flame-retardant acrylic rubber composition.