Factors That Affect Daily-use Ceramic Decal’s Lead and Cadmium Dissolution

As we know different decoration methods have determining impact on the lead and cadmium dissolution of daily-use ceramic’s decal. Aside from that, the following factors also have important influence on the lead and cadmium dissolution.

• Lead and cadmium content of the ceramic biscuit

It is a fundamental issue if the ceramic biscuit itself contains lead and cadmium. Even you use none lead and cadmium decoration, the finished products would still have high lead and cadmium content. Even if the white biscuit’s lead and cadmium content is qualified for FDA standard, decal it with non-lead decoration and firing under proper condition, the finished product’s lead and cadmium content would still be high above the FDA standard.

(2) Ceramic decoration pigment is lead-free or not

This is the primary factor, ceramic pigment can be divided into 3 category by it’s lead and cadmium content, which are with-lead, low-lead and lead-free. It is obvious that we should abandon with-lead pigment and promote lead-free pigment, low-lead pigment can be adopted to the products that dont have high requirement on lead and cadmium content.

(3) Firing condition

Firing condition includes heat method, construction of the kiln, firing temperature, holding time, ventilation condition. Heat method means the firing method the decoration firing kiln adopt, which is coal, electricity, liquefied gas or natural gas. Construction of the kiln means whether it is box-type , Shuttle, tunnel or roller. Of all these constructions, roller is the best choice for limiting the release of Lead and cadmium vapor molecules.

• Other factors

Thickness of the pigment, decoration area, position and density of products while firing in the kiln, soaking liquid, testing equipment, all these above factors affect the lead and cadmium content of ceramic products.

Below is a picture of our bone china products,  qualified for FDA standard.