JPH02281051A - Tread rubber composition for tire - Google Patents

Abstract

PURPOSE:To obtain the subject composition having excellent low-temperature characteristics and excellent performances on ice and snow free from problems of dust, etc., comprising rubber component having pts. wt. acetone chloroform extract satisfying a specific condition prepared by extracting vulcanized rubber with acetone and chloroform. CONSTITUTION:The objective composition which comprises diene-based rubber and at least one of silica and carbon black, satisfies E>1.2 (A-38) (E is pts. wt. of acetone chloroform extract based on 100 pst.wt. rubber component prepared by extracting vulcanized rubber with acetone chloroform; A is sum of pts. wt. carbon black and 1/2 pts.wt. silica based on 100 pst. wt. rubber component prepared by extracting vulcanized rubber with acetone chloroform) and uses 5 to 80 pst.wt. hard nonmetallic filler having 0.01 to 5mm average particle diameter and >=100kg/mm<2> Knop hardness based on 100 pst.wt. rubber component prepared by extracting the vulcanized rubber with acetone chloroform.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a tread rubber composition for tires.

(Conventional technology) Spiked tires that have been used conventionally have anti-skid,
Although the traction properties are good, it scrapes the general paved road surface,
Then the dust becomes a problem.

(Problems to be Solved by the Invention) The object of the present invention is to provide a tread rubber for tires that is non-spiked and has excellent performance on both ice and ice, in order to solve the above-mentioned problems on general paved roads. An object of the present invention is to provide a composition.

(Means for Solving Problem n) The present invention provides a tread rubber composition for tires containing at least one of diene rubber, silica, and carbon black, wherein the extractable component (E) defined below is (1 ) formula, and has an average particle size of 0.01 to 5 mm and a soup hardness of 100 kg/so-2 or more, a hard non-metallic filler is added to the rubber component 10 (1
It relates to a tread rubber composition for tires, characterized in that 5 to 80 parts by weight are used.

E>1.2(A-38) (1)E:
Rubber content after extraction of vulcanized rubber with acetone chloroform: 100
Part by weight of the acetone chloroform extract relative to part by weight A: 77 tons of Ia sulfur rubber 1/2 part by weight of car pump hook relative to 100 parts by weight of rubber after extraction with Aa form
The diene rubber components of the rubber composition of the present invention include natural rubber (NR), butanoene rubber (BR), styrene-butadiene rubber (SBR), inbrene rubber (rR), butyl rubber (IIR), and Blends of these can be used. At least one of silica and carbon black is blended into the rubber component. The silica and V car pump hook are preferably blended in an amount of 30 to 80 parts, preferably 35 to 55 parts, to 10011 rubber (the same applies below li parts by weight).

The rubber composition of the present invention has an extractable component (E) defined below (
1) Complete the formula.

E > 1.2 (A-38) (1) E: 11 parts by weight of the acetone chloroform extract based on 100 parts by weight of the rubber content after the acetone chloroform extraction of the vulcanized rubber A Near Jtl sulfur rubber after the acetone chloroform extraction The sum of carbon black parts by weight and 1/2 parts by weight of silica based on 100 parts by weight of rubber.Here, the above-mentioned 7 setone chloroform extraction method and the method for measuring the amount of polymer and carbon follow the method of J r S K6350, and the amount of silica is measured. is according to the method of JIS K6220, and the components extracted from 7 setone chloroform are mainly oil, anti-aging agent, and wax.

In the present invention, a hard non-metallic filler having an average particle diameter of 0.01 to 5 m and a soup hardness of 100 kg/mwb or more is further added to the vulcanized rubber in an amount of 5 to 50% by weight per 100 parts by weight of the rubber component after extraction of the vulcanized rubber with acetone chloroform. Soup hardness is measured according to JIS Z2251.The hard nonmetallic fillers include alumina, granite, quartz,
Limestone etc. can be exemplified. The preferred average particle size of the filler is 0.02 to 1 mm. If the particle size is less than 0.01 mm, the effect will be small, and if it exceeds 5 mm, the processing machine will be burdened heavily and there is a risk of breakage.

In the present invention, fillers with large particle diameters as described above have little reinforcing effect on rubber, and when these fillers with large particle diameters are blended with soft rubber, the hardness of the rubber as a whole increases, and the nominal performance is reduced. In addition, since the filler has a low binding effect on the rubber, it is microscopically soft, and therefore microscopically has good ground contact and good on-ice performance. Ice such as ice burns contains air bubbles on the order of 0.01-0.1-so, and if the 0.01-5-ring filler protrudes from the tread rubber surface, it will be difficult for the tire to pass over the ice. It is presumed that the presence of air bubbles causes the thin ice to break down, creating a catch and exhibiting great braking performance on ice.

In addition to the above-mentioned components, the present invention includes a known vulcanization cylinder, vulcanization accelerator, vulcanization accelerating aid, vulcanization retarder, organic overfill, reinforcing agent, filler, anti-aging agent, tackifier, Of course, coloring agents and the like can be added.

The rubber composition of the present invention can be obtained by kneading the above-mentioned components using a conventional processing device such as a roll, a Banbury mixer, or a Nigu.

The rubber composition of the present invention is suitably used in tires with a ground pressure in the range of 3 to 15 kg/cm, such as tires for trucks, buses, light trucks, and ultra light trucks. In the case of a ground pressure condition of ``10'', the rubber obtained from the rubber composition of the present invention has the effect of sinking into the ice plate, increasing the frictional force and improving the performance on snow.

(Effects of the Invention) The rubber composition of the present invention has excellent isothermal properties and is particularly suitable for use on icy roads and snow-covered roads.

(Example) Examples and comparative examples will be described below. Note that parts simply indicate parts by weight.

Examples and Comparative Examples 100 parts of the rubber listed in Table 1, Carbon Plaque N22
0 parts, silica parts, naphthenic oil parts, zinc white 3 parts, stearic acid 3 parts, anti-aging agent (Santo 7 Rex 1 part)
3) 1 part, puffin wax, 1 part, vulcanization accelerator (C
B, S) 1.0 parts and sulfur jl'2i were kneaded in a Banbury mixer for 4 minutes to obtain a rubber composition.

A pneumatic all-weather tire 650R1610PR with a radial structure was prepared using this rubber composition, and its hardness, performance on ice, and performance on snow were measured. Hardness is ASTM D
2228 at -5°C. Performance on ice and snow is based on actual vehicle tests on ice burns at -8 degrees Celsius and on cars. In either case, drive at a speed of 40/h and calculate the reciprocal of the stopping distance when suddenly braking.
, 3 tires are expressed as an index as 100,
The larger the value, the better. The results are shown in Table 1.6 Note that formulation Nos. 4 to 6 are examples, and the others are comparative examples.

Table 1 (continued) From Table 1, formulations Nos. 4 to 6 of Examples are excellent in performance on ice and performance on snow. However, formulations Nos. 1 to 3 that do not contain fillers have poor on-snow performance, while formulations Nos. 7 to 8 that use fillers whose particle size or blending amount is outside the range of the present invention.
has poor performance on snow. In addition, the soup hardness of alumina is 200.
0kg/Tenpaku2.

(that's all) Sender: Toyo Tire & Rubber Industries Co., Ltd. Representative Patent Attorney 1) Iwao Mura

Claims (2)

[Claims] (1) A tread rubber composition for tires containing at least one of diene rubber, silica, and carbon black, wherein the extractable component (E) defined below satisfies formula (1) and the average particle size is Soup hardness is 1 at 0.01-5mm
A tread rubber composition for tires, characterized in that 5 to 80 parts by weight of a hard nonmetallic filler having a weight of 00 kg/mm^2 or more is used per 100 parts by weight of the rubber component of the vulcanized rubber described below after extraction with acetone chloroform. E>1.2 (A-38) (1) E: Rubber content after extraction of vulcanized rubber with acetone chloroform 1
Weight part A of the acetone chloroform extract based on 00 parts by weight: Rubber content after acetone chloroform extraction of vulcanized rubber 1
Sum of parts by weight of carbon black and 1/2 parts by weight of silica based on 00 parts by weight (2) The tread rubber composition for tires according to claim 1, which is used in tires having a ground pressure in the range of 3 to 15 kg/cm^2.