Domestic production volume of synthetic rubber latices have been increased three-folds during these four decades. Major application field of SBR latex has been paper coating supported by various modification made for high-speed coating or new printing systems. SBR latex has been recently utilized for electrode binder of lithium-ion batteries. Accompanied with new technology, industrialized latices are expected to be essential materials for nanotechnology fields or high-end markets.

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Latex allergy (LA) is the allergic reaction triggered by proteins containing in natural rubber latex (NRL) or chemicals in NRL products. The pathophysiology of LA is divided into the immediate type (type I) allergy and the delayed type (type IV) allergy. Majority of LA is the allergic reactions mediated by specific IgE (sIgE) antibodies produced by contacts and exposures to NRL by inhaling the powder in the environments when wearing or removing the gloves made from NRL.
Recently, the frequency of immediate type allergy reaction is decreasing, but the delayed type allergy reaction caused by chemical substances added during glove manufacturing is increasing. Allergic contact dermatitis (ACD) caused by thiuram compound (a vulcanization accelerator), is increasing and it is clear that 80% of ACD cases in health care workers are sensitized to this substance.
For Diagnosis of LA, a detailed patient interview is the most important and sensitization to NRL is confirmed by a blood test or skin test to show an existence of sIgE antibodies to NRL. Also a positive provocation is useful for diagnosis.
Treatment for type I reactions is histamine H1 receptor antagonist or systemic steroids. However, in severe case such as anaphylactic shock, it is necessary to administer adrenaline. In case of type IV reactions, it is important to take local steroids or use moisturizing agents in addition to replace gloves free of vulcanization accelerator.

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Condoms, which are controlled medical devices, are easily utilized as they are low cost and cause no side effects. Condoms are increasingly used as one of the most effective means of birth control and prevention of sexually trans-mitted diseases.
When producing condoms, the dipping/drying processes are repeated twice during the molding. After being released from the mold, post-vulcanization is applied. The quality inspection of the finished products includes a bursting test which is used as a substitute for the “no tearing during use”　test. Japanese condoms of a thickness of 0.03mm had been used successfully in the past. After introducing the bursting test into ISO 4074, the condoms being 0.03mm in thickness became problematic to produce. However, the subsequent development of new technologies again enabled the production of the condoms with a thickness of 0.03mm. These are more suitable to new competitive rules, and the production of the condoms continues to this day.

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The brief outline of water adhesive using natural rubber latex and modified natural rubber latex are introduced. Also the new trend uses of the functionality modified natural rubber latex are mentioned.

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Rubber gloves are the indispensable items in our life. They protect our hand from an injury, a medicine wound, a virus and bacteria.
Over the past years, there has been a notable rise in the demand of gloves whenever there is an outbreak of flu or viral diseases. During and after such outbreaks, there is a sudden change in the demand for rubber gloves due to increased hygiene concerns. In addition, the demand for gloves from food industry and others services is also set to increase.
This report gives a production method and the market trend of rubber gloves.

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The mechanism of the chemical deterioration of black-filled ethylene propylene diene terpolymer (EPDM) in sodium hypochlorite (NaOCl) solution of pH 10 was studied at various temperatures from 277 to 323 K. At pH 10, free available chlorine (FAC) mainly exists as dissociated form, i.e., hypochlorite ion (OCl^-). When EPDM specimens were immersed in the NaOCl solution of 500 ppm for 7 days, decreases in pH and FAC concentration of the NaOCl solution occurred owing to the oxidative action of OCl^-. These changes became marked at 323 K, and the NaOCl solution became suspended by carbon black. X-ray photoelectron spectroscopy (XPS) analysis showed that C-Cl and C-O groups were formed on EPDM surface only at 313 and 323 K. It was also found that no significant diffusion of Cl and O into EPDM was observed at 277 to 303 K, but both their diffusion and the swelling of EPDM surface by water increased markedly at 323 K. These results suggested that the oxidative cleavage of EPDM by OCl^- was accelerated at 323 K, resulting in a decrease in the crosslink density of the surface. The diffusion of Cl and O into EPDM was probably due to the conversion of OCl^- to HOCl caused by a drop in pH at EPDM surface.

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