📁 专科
This category and its subcategories contain sites for businesses and business activities related to the manufacture, distribution, and sales of specialty chemical products. This includes primarily products defined by their suitability for a particular niche application or purpose, rather than by their chemical structure. Many of these are known in the chemical industry as specialty chemicals or performance chemicals. Sites for companies who focus on one particular specialty are listed in the corresponding subcategory; companies active in two or more specialty areas, and companies whose specialty does not fall within one of the subcategories, are listed in this main category.
