1,2-Dichlorobenzene

　　Colorless liquid, flammable. Melting point -15℃, boiling point 180.5℃, 86℃ (2.39 kPa), relative density 1.3022 (20/4℃), refractive index 1.5501, autoignition point 647.78℃, flash point 67℃. Insoluble in water, miscible with ethanol, ether, and benzene. Has an aromatic odor.

　　Main Uses

　　1. Solvent Applications

　　As a high-boiling-point solvent, used to dissolve grease, wax, resins, rubber, asphalt, and other difficult-to-dissolve substances; widely used in the production of coatings, inks, and adhesives;

　　In laboratories, used as an extraction agent to replace benzene (lower toxicity) for separating organic mixtures (e.g., extracting aromatic compounds from water).

　　2. Organic Synthesis Intermediate

　　Used in the synthesis of dyes (e.g., azo dyes), pesticides (e.g., insecticides, herbicides), and pharmaceutical intermediates (e.g., antifungal drugs);

　　Hydrolyzed to produce catechol, which is a key raw material for synthesizing vanillin, berberine, etc.

　　3. Other Uses

　　As an insect repellent (effective against moths and cockroaches) or for mold-proofing treatments of wood and fabrics;

　　As a degreasing agent in metal surface treatment to remove oil and impurities;

　　Used as a standard liquid for calibrating instruments (e.g., refractometers).