JPS58162335A - Rubber hose for connecting pipe for circulating gasoline - 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] The present invention relates to a rubber hose for connecting a gasoline circulation pipe, which is used to connect metal pipes to a joint between metal pipes.

The rubber hose (4) conventionally used for this purpose is shown in Figure 1. The inner tube rubber layer (1) has gasoline resistance, the fiber reinforcement layer), and the outer tube rubber layer (1) has weather resistance.
Consisting of a combination of three layers of materials,
As shown in Figure 2, the connection part is bent. Fit both ends to the outer periphery of the metal pipe (5) and tighten the fastening band (6).
It was fixed and attached.

However, in recent years, the automobile industry has developed significantly.

In particular, fuel pressure increases due to vehicle exhaust measures. Due to high temperature.
The temperature inside the engine room is over 100 degrees Celsius.

Compared to conventional fuel system hoses for automobiles, fuel system hoses for automobiles have a very wide temperature change of -40℃ or less, and gasoline circulates as oxidized gasoline at high temperatures (hereinafter referred to as sour gasoline). Various performances are required under various harsh conditions.

Conventional rubber hoses with an inner tube rubber layer (11) made of a general-purpose polymer having gasoline resistance can no longer be used.

Against this background, fluororubber (hereinafter abbreviated as FKM) is a material that satisfies the above performance.
KM has excellent heat resistance, sour gallbladder resistance, etc. However, because FKM has poor cold resistance and is very expensive compared to acrylonitrile-butadiene rubber (hereinafter abbreviated as NBR) used as a hose material, it is not practical to place it inside the outer tube rubber layer. The inner tube rubber layer is composed of an outer layer made of a compound such as NBR, and an FKM rubber layer.
The development of a rubber hose with a rabbit meat side layer made from a compound of

However, the practical application range of FKM is further limited by the above-mentioned limitations, and FKM cannot be bonded to other rubber materials such as NBR by normal means. During use, the hose would peel off and the hose would no longer function properly.

The present invention was invented based on the above circumstances, and provides a rubber hose for connecting gasoline circulation pipes in which a compound of FKM and a compound of NBH are firmly adhered without intervening an intermediate layer. The purpose is to
The cost is that the inner tube rubber layer located inside the outer tube rubber layer is an outer layer made of an NBR compound, and an FK
The NBR and/or FKMK is a 1,8-diazabicyclo(5,4.0)undecene-7 salt of a carboxylic acid represented by the following general formula (hereinafter referred to as a carboxylic acid DBU salt). ).

2 Ll i2 [几; alkyl group, phenyl group, naphthyl group, etc.] Hereinafter,
Furthermore, the present invention will be described in detail.

In the present invention, examples of the carboxylic acid DBU salt represented by the above general formula to be incorporated into NBR and/or FiFKM include naphthoic acid, 2-bitroxy-naphthoic acid.
Sorbic acid. DBU of carboxylic acids such as 2-ethylhexylic acid, gallic acid, P-hydroxy-benzoic acid, cinnamic acid, etc.
Salt is used.

Among these, DBU salts of naphthoic acid and sorbic acid are particularly preferred. Compounding amount: NBR or I/'iFKM per 100 parts by weight. 0.1~5 weight, preferably sail 5~35~
3 weight. If it is too small, there will be no effect on adhesion. This is because if the amount is too large, the interlayer adhesion under normal conditions is good, but the gasoline resistance deteriorates.

In addition, carboxylic acid DBU salt is F from the viewpoint of processability, dispersibility, etc.
The psychokinesis of NBRK is better than that of KM, and its effect on adhesion is even better.Although the mechanism of action of carboxylic acid DBU' is clearly not 25, it is effective at the interface between NBR and FKM. It is thought that this promotes co-crosslinking.

In the present invention, in order to further strengthen the adhesion between the inner layer (FKM compound) and the outer layer (NBR compound) of the inner tube rubber layer, the NBR compound constituting the outer layer is inside,
It is also possible to contain at least one selected from gold carp oxide, silica thread filler, and epoxy resin.

Ti, MgO, PbO, Al5O1 as metal oxides
2% is used, but KMzO is particularly preferred (the amount is 1 to 30 parts by weight per 100 parts by weight of N88).

Examples of silica-based fillers include acidic silica such as Nira 1 Seal VN-3 (trade name 1 Nippon Silica ■#) and basic silica such as Carplex 1120 (@14 people; manufactured by Kanogi Pharmaceutical Co., Ltd.). However, basic silica is preferred, and the amount of compounded silica is 5% for the heavy area of NBRIQQ.
~80 parts by weight.

Epoxy resins include thermoplastic resins having two or more epoxy groups in one molecule, but bisphenol A
It is preferable to use a type obtained by the reaction of epichlorohydrin with epichlorohydrin, such as Epikote 828 (product name; manufactured by Shell Chemical Co., Ltd.).
is 1 to 10 @g parts per part.

The FKM used in the present invention includes:

These are vinylidene fluoride-propylene hexafluoride copolymer and vinylidene fluoride-glopylene hexafluoride-ethylene tetrafluoride ternary copolymer.

The NBR used in the present invention includes:

Bound acrylonitrile content - regardless of carboxylic acid D
Although it is possible to find an effect on adhesion depending on the composition of the BU mound, when used under harsh conditions such as carcinerator-based hoses, the bound acrylonitrile content is 28-468-468.
46 parts by weight is preferred.

In the present invention, FKM may contain other known auxiliary materials 1, such as crosslinking agents (peroxide compounds, polyol compounds, dithiol compounds, amine compounds, etc.), crosslinking accelerators, and stabilizers, depending on the purpose.

There is no problem in adding colorants, plasticizers, reinforcing agents (car pump hooks, etc.), etc.

Also, in NBR, similarly known crosslinking agents, crosslinking accelerators, crosslinking accelerators, stabilizers, and plasticizers are used.

Fillers (carbon black etc.) etc. can be blended.

FIG. 3 shows one example of application of the present invention.
) Inner layer consisting of a formulation of FiFKM.

(1b) is an outer layer made of a blend of NBR, and the inner tube rubber layer has a double structure of (la) and (1b). (2)
(3) shows the reinforcing layer tube similar to the conventional one, and (3) shows the outer tube rubber layer.

9. An example of the method for manufacturing the rubber hose of the present invention is to extrude the NBR compound kneaded using a cooling roll and the FKM compound obtained in the same manner using an extruder for two layers, or to extrude the same using two extruders. After extruding the outer layer (NBR compound) onto the inner layer (FKM compound layer) using a machine, a fiber reinforced layer is formed on top of that, and then the outer tube rubber layer is extruded using an extruder to integrate and vulcanize. It makes it adhere.

Vulcanization conditions include temperature 145-170℃ for 1 hour 30~
90 minutes is commonly used.

As explained above, the FKM compound layer and NBA according to the present invention
The problem of adhesion with the compound layer has been solved, and the practical application range of FKM can be expanded thereby, which is a great practical benefit.

Hereinafter, the present invention will be specifically explained on the *male side, and the following example will show the case where a rubonic acid DBU salt is blended into an NBR9 formulation.

The formulation for forming the M compound layer on F used in the following examples is as shown in Table 1 below.

*1: Trade name: DuPont Co., Ltd. The formulation for forming the NBR compound layer is as shown in Table 2 below.

Test piece FKM compound layer and NBR compound layer were each rolled into 2M sheets and stacked on top of each other.
It was vulcanized at 45 ml of temperature and subjected to the following tests. Table 3 shows the test results.

(1) Adhesion under normal conditions: Based on JI8 6301 K (2) Adhesion after immersion in gasoline: After immersion in regular gasoline at room temperature for 72 hours, based on JI8 6301.

*3: Contains bound acrylonitrile 11181 weight - (trade name 1DN202, manufactured by Nippon Zeon Mai).

Table 8 Adhesion test results> Furthermore, the FKM compound and the NBR compound were coextruded as the inner layer and outer layer of the inner tube rubber layer, respectively, and a reinforcing layer made of braided polyester fiber was applied around the outer periphery.
A rubber hose was manufactured by applying an outer tube rubber layer made of a shrimp chlorohydrin comb compound. Vulcanization conditions are 160°C x 5 Qm
By i'n's leaded vulcanization. The thickness of each layer is 9.
511m, outer layer Q, 711. The outer tube rubber layer is 1.211. About the rubber hose obtained by K as above 1
The following performance tests were conducted. Table 4 shows the test results.

The numbers of the comparative examples and examples in Table 4 correspond to the numbers of the comparative examples and examples shown in Table 3 above.

Hose Sour Gasoline Circulation Test Lauroyl Peroxide 19 to Regular Gasoline 1
00rnl! A model sour gasoline was prepared by dissolving the gasoline in the following manner, and a circulation test was conducted at 40°C for too long. (Gasoline was replaced every 168 hours.) Thereafter, the adhesive strength between the inner layer of the inner tube rubber layer of the hose and the first layer of outer stick was measured.

Table-4 Hose performance test results *; Material destruction (rubber breakage)

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional hose, FIG. 2 is a vertical cross-sectional view showing how the hose is used, and FIG. 3 is a cross-sectional view of an embodiment of the hose of the present invention. 1... Inner tube rubber chest, Ia... Inner layer, lb...
・Outer layer 2... Reinforcement layer, 3... Outer tube rubber layer, 4...
・Gumhonu patent applicant

Claims (1)

[Claims] (1) Inner tube rubber FIII located inside the outer tube rubber layer. It is composed of an outer layer made of an acrylonitrile-butadiene rubber compound and an inner layer made of a fluororubber compound. (5,4,0) A rubber hose for connecting a gasoline circulation pipe, characterized in that it is composed of a mixture of undecene-7 lumber. 2 [R; alkyl group, phenyl group, naphthyl group, etc.] (21
7. A rubber hose for connecting a gasoline circulation pipe according to claim (1), wherein at least one selected from a composite oxide, a silica filler, and an epoxy resin is blended with the 7-crylonitriloptadiene rubber. (3) A rubber hose for connecting a gasoline circulation pipe according to claim (2), wherein the silica filler is a basic silica filler. (4) Carboxylic acid 1,8-diazabicyclo[5,4,
0) Undecene-7 salt is 0.1 to 5 parts by weight per 100 parts by weight of acrylonitrile-7tadiene rubber or fluororubber.
Claims (1) to (3) containing parts by weight
Rubber hose for connecting gasoline circulation pipes as described in ). (5) Carboxylic acid 1,8-diazabicyclo(5,
4,0) The carboxylic acid of undecene-7 salt is naphthoic acid,
A rubber hose for connecting a gasoline circulation pipe according to claims (1) to 6), which is any one of sorbic acid. (6) A rubber hose for connecting a gasoline circulation pipe according to claims (1) to (5), wherein the acrylonitrile-butadiene acrylonitrile content is 28 to 46% by weight.