JPH02227303A - Tire - Google Patents

Abstract

PURPOSE:To enjoy abrasion resistance on a general road surface as well as to improve a running ability on ice and snow both by vulcanizing a gelatin- containing rubber composition, and using a tread made up of vulcanized rubber with bubble in a specified mean aspect ratio. CONSTITUTION:A rubber composition, containing gelatin of less than about 500mum in mean grain size as much as about 5 - 50 parts to rubber ingredient 100 parts, is vulcanized, forming vulcanized rubber with a bubble of below 0.7 in mean aspect ratio. This vulcanized rubber is used for a tread. With this constitution, abrasion resistance on a general road surface is maintained, and roadability on ice and snow both is improvable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a tire suitable not only for general paved roads but also for icy roads and snow-covered roads in particular.

(Technology in the United States) When driving on icy roads in the United States, it has been common practice to use so-called spiked tires with spike pins driven into the tire tread, but in recent years spiked tires have caused damage to the road surface and The associated dust generation, floating, and noise have become major social problems. For this reason, so-called studless tires, which do not require spike pins even on icy roads, are being used. However, studless tires have problems in wear resistance and heat generation.

It has also been proposed to mix short aJI into rubber, but this is disadvantageous in terms of wear resistance and durability, and it has also been done to form bubbles in the tread rubber by adding salt, etc. However, this has the disadvantage of damaging the steel cord. Furthermore, there is a method of producing foamed rubber using an organic or inorganic foaming agent, but this is extremely difficult to control due to the relationship between the foaming state and the vulcanization rate, temperature, viscosity, vulcanization pressure, etc. of the rubber.

(Problems to be Solved by the Invention) An object of the present invention is to provide a tire that maintains wear resistance on general road surfaces and has improved performance on ice and performance on snow.

(Means for Solving the Problems) The present invention vulcanizes a rubber composition containing gelatin, and vulcanizes the gelatin-containing rubber composition.
The present invention relates to a tire characterized by using a tread formed from vulcanized rubber having cells having an average aspect ratio of 7 or less.

As the rubber component of the tread of the tire of the present invention, natural rubber (NR), butadiene rubber (BR), styrene butane rubber (SBR), isoprene rubber (IR), butyl rubber (IIR), and blends thereof can be used. .

In the present invention, by compounding gelatin, which is a natural high-performance polymer material, with rubber, it is possible to obtain a foamed rubber tire that has a characteristic structure and microporous open cells, especially due to the reaction at the rubber-gelatin interface. Can be done. That is, it is presumed that gelatin is kneaded into rubber and a portion of the gelatin is denatured at high temperatures during the vulcanization reaction to form microporous open cells. Furthermore, since gelatin has a parent wood group and a hydrophobic group in the same molecule, it has excellent moisture absorption and desorption properties.

As described above, the water film interposed between the tire tread surface and the ice can be removed in a short time using bubbles and ionic functions, improving the frictional force on icy and snowy roads.

In the present invention, the average particle size of the gelatin is preferably less than 500 microns, particularly preferably in the range of about 20 to 450 microns.

When the particle size is 500 μm or more, the braking performance on ice of the vulcanized rubber is slightly improved, but the wear resistance is deteriorated.

The amount of gelatin added is generally 100 parts of the rubber component (parts by weight,
(same below) is preferably about 5 to 50 parts, and about 10 to 50 parts.
40 parts is more preferable, and the average aspect ratio (minor axis/bread axis ratio) of the resulting bubbles is 0.7 or less.The aspect ratio is measured by using an optical microscope on the cut surface of the tread rubber of the test tire. Photographs were taken at about 300 times magnification, and the short axis length and angle of about 100 bubbles were measured, and the aspect ratio was calculated and averaged to 1.

When the aspect ratio exceeds 0.7, the effect of improving performance on ice and snow is small.

In addition to the above-mentioned components, the present invention also includes known vulcanizing agents, vulcanization accelerators, vulcanization accelerators, vulcanization retarders, organic peroxides, reinforcing agents, fillers, anti-aging agents, tackifiers, Of course, coloring agents and the like can be added. As the filler, 20 to 150 parts, preferably 3 parts, of known fillers such as carbon black, silica, and clay calcium carbonate are used per 100 parts of rubber.
It is preferable to mix 0 to 100 parts.

The tire of the present invention can be manufactured by a conventional method using a rubber composition obtained by kneading the above-mentioned components in a conventional processing device such as a roll, a Banbury mixer, a Nigoo, etc. for the tread portion.

(Effects of the Invention) The tire of the present invention has excellent wear resistance and low-temperature characteristics, 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 black N33
9 parts, gelatin parts, naphthene oil parts, zinc white 3
1 part, stearic acid 2 parts, anti-aging agent (Santoflex 13) 2 g, paraffin wax 1 part, vulcanization accelerator (C
A rubber composition was obtained by kneading 1.7 parts of B S ) and 1.7 parts of sulfur in a Banbury mixer for 4 minutes, and a tire with a tire size of 165/80R13 using this as a tread was obtained by a conventional method. . Comparative Example 1 is a case in which no gelatin is used, and Comparative Example 2 is a case in which a blowing agent (dinitrosopentamethylenetetramine) is used instead of gelatin.

The obtained rubber composition was mold vulcanized at 160° C. for 20 minutes. Hardness was measured at -5°C according to ASTM D2228. Braking performance on ice is tires 165/80R1
3, lock the tires at a speed of 40 km/hr in a waterway, and calculate the reciprocal of the distance until the car stops as Comparative Example 1
is displayed as 100. The larger the value, the better the braking performance on ice. For braking performance on snow, the same test as for braking performance on ice described above was conducted on snow.

Wear resistance was measured by measuring the amount of wear after running 10,000 kg + Comparative Example 1
The tires are expressed as an index with 100 as the number of tires. The larger the value, the better. What BR did you use? ) Isis BRSSBR
is a solution polymerized SBR with a styrene content of 18%. The results are shown in Table 1. Blend Nos. 1 to 7 are examples, and the others are comparative examples.

No. table No. table (continuation) (Hereafter Up) Out wish Man Toyo Rubber Industries Co., Ltd. teenager Reason Man

Claims (1)

[Claims] (1) Vulcanize a rubber composition containing gelatin,
A tire characterized by using a tread formed from vulcanized rubber having cells having an average aspect ratio of: