This standard is applicable to bleached shellac and refined bleached shellac. This standard is proposed with reference to the international standard ISO 57-1975 "bleached shellac". GB 8140-1987 Bleached shellac GB8140-1987 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Bleached lac
Bleached lac
This standard applies to bleached lac and refined bleached lac. This standard is proposed with reference to the international standard ISO 57-
1975 "Bleached lac":
UDC 634. 0. 892.6
GB 8140-87
Replaces LY207--76
Bleached lac refers to light-colored lac made from lac raw material or granular lac, dissolved in sodium carbonate solution or other weak alkaline solution, and then bleached with a bleaching agent to remove impurities or lac wax; bleached lac containing wax is ordinary bleached lac; dewaxed bleached lac is refined bleached lac. 2 Technical requirements
The technical indicators of bleached lac are as follows.
Color index, No.
Water content, %
Hot ethanol insoluble matter, %
Ash content, %
Wax, %
Water soluble matter, %
Acid value, KOHmg/g
Fluorine content, %
Inorganic acid (in HSO.), %bzxz.net
Free chlorine and peroxide
Note: ①Storage period: one year for grade 1 and 8 months for grade 11. ②The product is not allowed to contain rosin and other adulterants. ③Iodine value and saponification value shall be agreed upon by both parties if necessary. ①All indicators in bleached shellac are calculated based on the results of absolute dry samples. 3 Other provisions
Ordinary bleached shellac
Refined bleached shellac
3.1 If the products of this standard become insoluble in alcohol within one year for Grade 1 products and within eight months for Grade 1 products from the date of production, the buyer may request a return or compensation.
3.2 Other provisions of this standard shall be implemented in accordance with the provisions of GB8138-87 "Lac Sheet". 4 Packaging, transportation and storage
4.1 Bleached shellac is packed in wooden boxes or other packaging materials, lined with kraft paper. The net weight of each box is 25kg. The manufacturer, product name, grade and production date are marked on the box, and the words "sun protection" and "moisture protection" are marked. The product inspection certificate is placed in the box. 4.2 The storage and transportation time of the product should be reduced as much as possible. During transportation, it is strictly forbidden to be exposed to the sun, rain, or close to heat sources or humid places. Approved by the Ministry of Forestry of the People's Republic of China on November 12, 1987. Implementation on May 1, 1988. GB 8140-87. The product should be stored in a dry, ventilated, and cool room to prevent caking. 4.3. Product inspection. The technical indicators of bleached shellac shall be carried out in accordance with GB8143-87 "Testing methods for shellac products". Additional notes: This standard was drafted by the Institute of Forest Chemical Industry, Chinese Academy of Forestry. The main drafters of this standard are Wu Tongfang, Yang Luan, Ma Wanqing, and Wei Chaokuan. 126
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