Sun photochromic materials raw powder

1. Basic colors
OP powder has a variety of colors to choose from, such as purple, blue, yellow, green, red, etc., different colors of OP powder can be mixed and used to match more diverse color changes. More than 100 colors are available. And can provide customized products according to the customer’s application in the segmentation scenario.
2, color change conditions
OP powder itself by ultraviolet irradiation does not change color, need to dissolve in the medium (such as organic solvents, resins, plastics) to photochromic change; Dissolved in different polar media, the color change will be different. The product is colorless (or the color of the product) in the dark state or indoor light source environment, and the color of the product will soon appear under ultraviolet light or sunlight, and the ultraviolet light source will become colorless (or the color of the product).
3. Excitation wavelength
It has strong absorption of UV in the range of 280nm-400nm and can stimulate the discoloration of OP powder.
4. Solubility
OP powder can be dissolved in most organic solvents, such as ethyl acetate, butyl acetate, tetrahydrofuran, acetone, benzyl alcohol, toluene, styrene, etc. Photochromic dyes are less soluble in more polar solvents, more soluble in less polar or non-polar solvents, and do not exhibit photochromic properties such as acetonitrile in individual solvents.
5, pH applicability
The discoloration performance of OP powder is stable in neutral environment, and slightly poor in alkaline or acidic environment.
6. Weather resistance
Long-term exposure to high-intensity ultraviolet rays will reduce the frequency of OP powder discoloration and the color rendering effect, thus shortening the service life of photochromic powder. The weather resistance of different OP powder is different, and the weather resistance of the same OP powder in different media is also different. In order to improve the weather resistance, a certain amount of protective agents can be added according to the specific situation, such as antioxidants, light stabilizers, etc.

Other information
1, should try to avoid the heating process above 250℃, some products should be processed below 180 ℃.
2, should be sealed in a dry, closed, dark place, avoid direct sunlight.