Development of high-purity gallic acid and its application in electronic chemistry

Electronic chemicals generally refer to special chemicals for the electronics industry. At present, there are tens of thousands of varieties, which are request high quality requirements,low consumption,high requirements for the cleanliness of the production and use environment and upgrating quickly .Ultra-clean high-purity chemical reagents (also known as Wet Chemicals, or Process Chemicals), also A very important member of electronic chemicals, mainly used for chip cleaning (including drying), photolithography, etching, development, film removal, doping Miscellaneous, involving more than 80 special chemicals.This reagent includes ultra-clean high-purity acid And alkalis, ultra-clean and high-purity organic solvents and ultra-high-purity etchant. Here we are introducing the new products of this family-high-purity gallic acid
Gallic acid (GA), also known as gallic acid, gallic acid, is a white or light yellow needle-like crystal or powder, its chemical name is 3,4,5-Trihydroxyl benzoic acid (3,4,5-Trihydroxyl benzoic acid). ), molecular formula C7H6O5, molecular weight 170.12, throughIt usually exists in the form of a monohydrate with a specific gravity of 1.694 and a melting point of 235 to 240°C (decomposition). When heated to 100~120℃, it loses Crystal water: When heated to above 200 ℃, it will lose CO2. It produces pyrocarbon GA; it is easily soluble in hot water, ether, ethanol, acetone and glycerin, but difficult Soluble in cold water, insoluble in benzene, acetic acid and chloroform; lethal dose for rat subcutaneous injection is 4000mg/Kg: the pH value of the aqueous solution is 3~4; It has strong reducibility, astringent and astringent taste, can reduce gold and silver salts and Fehling’s solution, and react with ferric chloride to produce blue-black Precipitation, currently an important fine chemical mainly produced with gall or tara as raw materials.
Gallic acid has a wide range of applications, widely used in organic synthesis, coatings, dyes, medicine, food, chemicals, tanning, daily chemicals,agriculture, minerals, etc., mainly used in the manufacture of drugs, dyes, inks, and also used as food antioxidants, preservatives, metal extractants,ultraviolet absorber, disinfectants, hemostatic astringents, imaging agents, chemical reagents, mud fluidizing agents and grape growth agents, etc. In addition to meeting domestic demand, the product is mainly sold abroad. It is an important fine chemical ingredient material.
In recent years, the electronic chemical grade and high-purity gallic acid has been used in the US electronics industry to wash large-scale integrated circuit boards.
Its quality requirements are particularly strict, the main indicators are: GA≥99.5%, Na, K,Fe, Cu, Pb, Al, Cr, Zn, Mn, Ni are all≤0.1 mg/kg (that is, the residual amount of metal ions is 1*10-7 level). Therefore, to remove trace metal ions in gallic acid is to prepare the key to high purity gallic acid.

Post time: May-07-2021