CHEMICAL MARKER AND PREPARATION METHOD THEREOF Russian patent published in 2012 - IPC C09D123/12 C09D123/30 C07D307/885 G01N21/78 

FIELD: chemistry.

SUBSTANCE: invention relates to production of special chemical substances used for concealed marking of substances, materials and articles, and can be used when conducting different types of examination of trading and industrial enterprises. The chemical marker contains the following in wt %: 42.3-50.2 phenolphthalein, 5.3-12.5 o-cresol phthalein, 5.3-6.3 thymolphthalein, 0.1-1.0 fluorescein, 20.0-30.0 silica gel, 2.0-4.1 citric or oxalic acid, 5.0-15.9 low-oxidised atactic polypropylene. The chemical marker is obtained by depositing an adhesive polymer on the outer surface of powdered phthalein particles. The phthalein mixture is pre-suspended in 10-15% solution of low-oxidised atactic polypropylene in hexane or benzene. The solvent is distilled off by heating the suspension to boiling. The powder is dried in a thin layer of thickness 2-5 mm in air at 15-25°C. Silica gel and carboxylic acid are then fed, followed by homogenisation of dry components with intense mixing.

EFFECT: longer time for integrity of concealed marking on marked objects, high illegality of use of the markers and reliable identification thereof during examination.

2 cl, 1 tbl, 6 ex