Simalin Chemicals Industries Limited manufactures Hexamine with White Colour Crystalline Solid Form. Simalin Chemicals Industries Limited is an ISO 9001:2000 awarded company. The company manufactures high quality chemicals products. The Hexamine with White Colour Crystalline Solid Form may produce a rash to affected area [in particular the wrist, ankles, belt line, and collar area of the neck] similar in appearance to poison ivy. Hexamine may decompose to formaldehyde in the presence of perspiration [slightly acidic pH 4-6.5]. The formaldehyde is trapped in the sweat pores of the skin and then oxidized to formic acid, which is believed to be the actual agent responsible for the skin rash.