For products that require toning, there may be some difference in color between batches, even if it is usually said.
Because visual judgment of color difference is greatly affected by environmental light source, observer color sensitivity, observation mode and sample material, surface roughness, size and other factors, lack of quantitative effect, it is inevitable that unnecessary disputes will occur.
Regarding quantitative characterization of chromatic aberration, the national standard stipulates the judgment of chromatic aberration. In the national standard GB/T 18922-2008 "Representation of architectural colors", it is specified that the color difference ΔE*ab of the standard color card should be less than 3.
In order to standardize the management of our special color products, better control the color difference of products, and eliminate the uncertainty of visual color difference, the color difference control of our special color glue refers to the methods and indicators of the above national standards, that is, the color difference is measured by colorimeter. The color difference between the actually produced glue and the standard plate is △E*ab≤3.
Why does the sealant change color?
After the sealant is applied, discoloration may occur. There are usually two reasons for discoloration.
1. Silicone sealant is incompatible with the sealant strip.
The light silicone sealant is incompatible with EPDM strips and yellowing occurs.
Light-colored silicone sealant is in contact with acid and alkaline substances such as certain exterior wall cleaning fluids, cement slurries, etc., and discoloration occurs.
In order to prevent the discoloration of the silicone sealant, the compatibility of the accessory material that should be in contact with it should be tested before use, and the accessory material compatible with the silicone sealant should be selected. After the sealant is applied, try to avoid contact with acidic or alkaline substances.