Import the Carbopol resin carbomer is a copolymer of polyalkyl sucrose or polyalkyl pentaerythritol with acrylic acid crosslinked polymer. , Depending on the different materials used for polymerization, and the degree of polymerization, the formation of a variety of pharmaceutically acceptable specifications of the products, commonly used with carbomer 934P, carbomer the 940GE, carbomer 941GE, wherein GE representative pharmaceutical grade, P represents oral grade, Carbomer 940GE can be used for topical formulations, and Carbomer 934P can be used for oral formulations. Carbomer white loose powder, with a strong hygroscopicity. Containing 52 to 68% of the acid groups due to their molecular structure and therefore has a certain acidic, the pH of the 1% water dispersion is 2.5 to 3.0. Available alkaline substance and form a gel. Carbomer is neutralized and the carboxyl group ionized due to the mutual repulsion of the negatively charged, so that the molecular chain diffusion stretch, was greatly expanded state, and a viscous. 0.5% carbomer the 934GE and carbomer 940GE neutral aqueous dispersion viscosity, respectively the of of 30 ~ 40Pa.S and 40 ~ 60Pa.S,. The hydrogel system of effective thickening range PH5 ~ 10. The carbomer continuity and function of the physical and chemical properties different carbomer, performance is different, but the same continuity [appearance] loose white the slightly acidic powder [pH value] 2.5-3.0 (1% aqueous dispersion) [Stacked density] of about 208 kg / m 3 (13 lb / cubic feet) [pH value of 2.7-3.5 (0.5% aqueous dispersion) [gravity] 1.41 [equivalent] 76 + / -4 [transporting water content] maximum 2.0% When the [Asher content] 0.009ppm (average) [equilibrium water weight] 8-10% (relative humidity of 50%) [Glass transition temperature] 100-105 ℃ (212-221 ° F) Carbomer at low amount (0.25-0.5%) of the conventional dosage, will be able to generate efficient thickening effect, thereby preparing a wide viscosity range and different rheological properties of emulsions, creams, gels and transdermal formulations.