Items

Standard

Appearance

Shallow pink to shallow brown crystalline powder

Purity

≥99.0%

Initial melting point of dry product

≥156.0 ℃

Phenol

≤0.20%

Ash specification

≤0.30%

Items

Standard

Appearance

White blocky crystalline or crystalline powder, allowing a little yellow and light pink.

Purity

≥99.0%

At the beginning of melting point

≥158.0 ℃

Moisture content

≤0.40%

Phenol

≤0.20%

Easy carbon

Not deeper than 6

Dark spot

≤12个/20 g

Foreign matter

≤5A/a

Items

Standard

Appearance

White or Almost white crystalline powder or colourless acicular crystals

Solubility

Slightly soluble in water, freely soluble in ethanol (96 per cent), sparingly soluble in methylene chloride

IdentificationA.Melting point of salicylic acid

158—161 ℃

IdentificationB. IR-Spectrum

Should be complied with Reference Spectrum

Appearance of solution

Clear and colorless

Chloride

≤100 ppm

Sulfate

≤200 ppm

Heavy metals

≤20 ppm

Loss on drying

≤0.5%

Sulphated ash

≤0.1%

Related substances

4-hydroxybenzoic acid

≤0.1%

4-hydroxyisophthalic acid

≤0.05%

Phenol

≤0.02%

Other impurities

≤0.05%

Total impurities

≤0.2%

Assay

99.0%—100.5%

Items

Standard

Appearance and smell

White fine needle crystal or white crystalline powder; odorless or almost odorless

Solubility

Freely soluble in ethanol or ether, soluble in boiling water, sparingly soluble in chloroformslightly soluble in water

Melting point

158～161 ℃

Identification (1) Colorreaction

Violet color is produce

Identification（2）IR-Spectrum

Should be complied with Reference Spectrum (Spectral set 57)

Residue on ignition

≤0.1%

Heavy metals

≤10 ppm

Related substances

4-hydroxybenzoic acid

≤0.1%

4-hydroxyisophthalic acid

≤0.05%

Phenol

≤0.02%

Other impurities

≤0.05%

Total impurities

≤0.2%

Assay

≥99.5%