Quality check of Chinese zinc phosphate. How not to be deceived?
Thanks to the development of import substitution, the domestic paint-and-vanish industry is gaining momentum. The producers and suppliers of raw materials keep abreast with its development, improving quality with each passing day, trying to take the upper hand of their foreign colleagues. Some try to achieve it by fair means and ways, while others through deception and fraud.
In early November of this year the Kronakril plant sent to an independent accredited laboratory “Testing center for surfactants, detergents, paint and varnish materials” samples of zinc phosphate pigment, that belong to cheap segment of products:
- ZP brand, manufactured by Kronakril Plant, Russia,
- Y55 brand, manufactured by DEQING TONGCHEM CO. China, batch of 12.2016
«Mass fraction of zinc compounds in terms of Zn in the sample of the ZP brand of zinc phosphate amounts 17.3%; the sample meets the requirements of TU (Technical Specification).
Mass fraction of zinc compounds in terms of Zn in the sample of the Y55 brand of zinc phosphate amounts 13.5%.»
The obtained test results contradict the value of zinc content, specified in the quality certificate (Zn).
These brands feature the lowest price, while the zinc content of 14% represents the borderline value; the lesser values jeopardize anti-corrosion properties, hence, leading to consumer complaint, received six months after the manufactured coatings application.
The Kronakril Plant strongly recommends to check the source raw material with care, since the quality of the manufactured products depend on these checks.
After checking quality and composition of the product, we recommend you to check them against the price using the following formula and table:
The formula for calculating:
E = (Zn * 3.17) / 100 + 0.85 / (74 / PO4), where:
Zn – content of Zn in the pigment (data of quality certificate),
PO4 – content of PO4 in the pigment (data of quality certificate),
E – the raw material cost of the product excluding VAT.
|Core components||Content in the product||Price per 1 ton without VAT||Price per 1 kg||The price of 1kg content in the product|
By performing these calculations, we get the raw material cost of the product of 0.73$ without VAT 18%, which does not include the production costs (20-30%), transportation (5-7%), sales charges, etc.
The conclusion is obvious - the zinc-phosphate based pigment, priced at 82-88 rubles, cannot contain 45% zinc. Do not let others take advantage of you - check raw materials and work with reliable suppliers!