Abstract: The present invention relates to a method of reducing allergenicity of natural rubber latex products caused by allergens by reducing extractable protein levels found for said products, said method comprising the steps of: subjecting said products to a wash in a strong alkaline solution to deteriorate the allergens, and a system for reducing allergenicity of natural rubber latex products caused by allergens by reducing extractable protein levels found for said products, and a product, such as a glover or condom, manufactured from natural rubber latex.

Abstract: Disclosed is a method and apparatus for the extraction of high molecular weight biopolymers from plants. Specifically, invention described herein relates to the commercial processing of plant material, including that from desert plants native to the southwestern United States and Mexico, such as the guayule plant (Parthenium argentatum), for the extraction of biopolymers, including natural rubbers. More specifically, the invention relates to laboratory to commercial scale extraction of high molecular weight biopolymers from plant materials including the chemical and mechanical processing of the plants and purification of the extracted biopolymer.

Abstract: There are provided natural rubber free from substances which cause Type I allergy, a rubber compositions having good processability and physical properties which comprises the natural rubber and other rubber, and a tire product comprising the natural rubber. The natural rubber of the present invention exhibits the above properties by containing substantially no proteins specified by the bands of 14, 31 and 45 kDa by SDS-PAGE.

Abstract: 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.

Abstract: A method of preparing a low allergic natural rubber latex which is less likely to cause allergy, comprising adding a protease having an exopeptidase activity to a natural rubber latex and aging the natural rubber latex, thereby to decompose a protein in the latex to such a degree that the protein and a protein decomposition product, which have a number-average molecular weight of 4500 or more, are not detected; a method of preparing a deproteinized natural rubber latex which is less likely to cause allergy, comprising adding an alkali protease to a natural rubber latex, thereby to decompose a protein in the latex, adding a protease having an exopeptidase activity, thereby to further decompose the protein and a decomposition product thereof in the latex, and removing the protein and the decomposition product thereof; a low allergic natural rubber obtained by a decomposition treatment of a protein, wherein the protein and a protein decomposition product, which have a number-average molecular weight of 4500 or m

Abstract: 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.

Abstract: A method of reducing allergenicity of latex rubber products such as latex rubber gloves. The latex rubber product is treated with first bath of an alkane hydrocarbon followed by a protein substituting material in the form of a synthetic plasticizer. A final wash is carried out using an alkaline or oxidative wash to remove surface and interstice dwelling protein.

Abstract: A method of preparing a low allergic natural rubber latex which is less likely to cause allergy, comprising adding a protease having an exopeptidase activity to a natural rubber latex and aging the natural rubber latex, thereby to decompose a protein in the latex to such a degree that the protein and a protein decomposition product, which have a number-average molecular weight of 4500 or more, are not detected; a method of preparing a deproteinized natural rubber latex which is less likely to cause allergy, comprising adding an alkali protease to a natural rubber latex, thereby to decompose a protein in the latex, adding a protease having an exopeptidase activity, thereby to further decompose the protein and a decomposition product thereof in the latex, and removing the protein and the decomposition product thereof; a low allergic natural rubber obtained by a decomposition treatment of a protein, wherein the protein and a protein decomposition product, which have a number-average molecular weight of 4500 or m

Abstract: 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.

Abstract: A deproteinized natural rubber substantially free from any protein and a process for producing the same which comprises treating a latex with a protease and a specific surfactant or a combination of specific surfactants and separating rubber particles are disclosed. A method for elevating the green strength of a natural rubber and a method for lowering the green strength of a natural rubber are also disclosed. Furthermore, a means for preventing allergy induced by natural rubber is also disclosed.

Abstract: 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.

Abstract: A process for producing a natural rubber for a pressure-sensitive adhesive, which comprises decreasing a molecular weight of an unmasticated natural rubber by the action of a peptizing agent while dissolving the unmasticated natural rubber in an organic solvent, and a natural rubber-based pressure-sensitive adhesive composition comprising a natural rubber having a weigh average molecular weight Mw of 700,000 or less obtained by the process.

Abstract: 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.

Abstract: A deproteinized natural rubber substantially free from any protein and a process for producing the same which comprises treating a latex with a protease and a specific surfactant or a combination of specific surfactants and separating rubber particles are disclosed. A method for elevating the green strength of a natural rubber and a method for lowering the green strength of a natural rubber are also disclosed. Furthermore, a means for preventing allergy induced by natural rubber is also disclosed.

Abstract: A deproteinized natural rubber substantially free from any protein and a process for producing the same which comprises treating a latex with a protease and a specific surfactant or a combination of specific surfactants and separating rubber particles are disclosed. A method for elevating the green strength of a natural rubber and a method for lowering the green strength of a natural rubber are also disclosed. Furthermore, a means for preventing allergy induced by natural rubberis also disclosed.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A process for culturing bacteria is disclosed in which is utilized as a bacterial nutrition a serum byproduced upon treatment of a natural rubber latex. The serum has an ample supply, a low cost, a stable quality and a sufficient activity over a wide variety of bacteria, thus contributing to accelerative growth for aerobic and anaerobic bacteria.