摘要:
The present invention provides a rubber composition that improves processability and fuel efficiency without decreasing mechanical strength and abrasion resistance, which are excellent properties of natural rubber, and a pneumatic tire using the rubber composition for a tire tread. Specifically, the present invention provides a rubber composition for a tire tread comprising 5 to 150 parts by weight of silica having nitrogen-adsorbing specific surface area of 100 to 300 m2/g and/or 5 to 150 parts by weight of carbon black having nitrogen-adsorbing specific surface area of at least 70 m2/g and dibutyl phthalate oil absorption of at least 70 ml/100 g, based on 100 parts of a rubber component containing 5 to 100% by weight of a deproteinized natural rubber having a weight average molecular weight of 1,400,000 and nitrogen content of at most 0.1% by weight, and a pneumatic tire comprising the rubber composition for a tire tread.
摘要:
Disclosed are a cationic deproteinized natural rubber latex, in which rubber particles are positively charged and the concentration of said rubber particles is from 40 to 65% by weight and that the viscosity at 25° C. of said latex is 200 mPa·s or less, a method of preparing said latex which comprises subjecting to a deprotenization treatment using a proteolytic enzyme and a deproteinizing agent made of one or more surfactant selected from cationic and nonionic surfactants, and optionally adding a post additive comprising a cationic or nonionic surfactant as an active component, thereby to enable both surfactants described above to coexist, and a treating agent used in the same.
摘要:
Disclosed are a deproteinizing agent comprising a proteolytic enzyme and one or more cationic surfactants selected from the group consisting of an alkylamine salt, an alkylamine derivative and quaternized compounds thereof; and a method of preparing a cationic deproteinized natural rubber latex, which comprises adding said deproteinizing agent to a field latex or an ammonia-treated latex thereby subjecting the latex to a deproteinization treatment and purifying the rubber particles in the latex.
摘要:
A method for lowering the extractable protein content in a natural rubber latex to below 30 parts per million (ppm) comprises the steps of treating by washing a rubber article, such as a rubber glove, with an aqueous solution containing a soluble silicate and, optionally, a protease. The methods claimed effectively reduce the allergenicity of the articles so treated.
摘要:
A method for producing a formed product of deproteinized natural rubber latex capable of reducing a content of an allergen in a natural rubber latex material to a level sufficient to keep the latex from being harmful to the human body without decreasing yields of the product and deteriorating formability of the latex. In the method, cleaning removal of a non-rubber content is carried out after each of protein decomposition, prevulcanization and forming. An aqueous alkali solution, ammonia, water containing free chlorine in an amount of 0.005 to 0.02% by weight or alcohol-water mixed liquid containing alcohol in an amount of 5 to 80% by weight is used as cleaning liquid for the cleaning removal. The method is suitably applied to production of a natural rubber product such as a rubber glove, a condom, a catheter, a foam rubber material and the like.
摘要:
The present invention provides a rubber composition that improves processability and fuel efficiency without decreasing mechanical strength and abrasion resistance, which are excellent properties of natural rubber, and a pneumatic tire using the rubber composition for a tire tread. Specifically, the present invention provides a rubber composition for a tire tread comprising 5 to 150 parts by weight of silica having nitrogen-adsorbing specific surface area of 100 to 300 m2/g and/or 5 to 150 parts by weight of carbon black having nitrogen-adsorbing specific surface area of at least 70 m2/g and dibutyl phthalate oil absorption of at least 70 ml/100 g, based on 100 parts of a rubber component containing 5 to 100% by weight of a deproteinized natural rubber having a weight average molecular weight of 1,400,000 and nitrogen content of at most 0.1% by weight, and a pneumatic tire comprising the rubber composition for a tire tread.
摘要:
A puncture sealing agent for sealing an inner surface of a tire comprises a deproteinized rubber latex that is formed by removing protein from a natural rubber latex. The puncture sealing agent includes nitrogen content at 0.1 wt. % or less of rubber solid content of the deproteinized rubber latex, and ammonia content at 0.5 wt. % or less of the rubber solid content.
摘要:
Medical devices of synthetic rubber are prepared from cis-1,4-polyisoprene by dip molding without the use of sulfur containing components. The devices have surprisingly favorable tensile characteristics despite what is known in regard to synthetic cis-1,4-polyisoprene. In addition, the absence of both the proteins present in natural rubber and the sulfur components that are typically used in vulcanization of both natural rubber and cis-1,4-polyisoprene of the prior art renders the devices freely usable without causing the user to suffer Type I or Type IV allergic reactions that typically arise from contact with natural rubber.