Production process of color-changing pearlescent pigment

Abstract

This application discloses a production process of a color-changing pearlescent pigment. The substrate of the color-changing pearlescent pigment is coated with an iron oxide layer, a titanium dioxide layer and a silicon dioxide layer by a hydrolysis method; the silicon dioxide layer is located between the iron oxide layer and the titanium dioxide layer. When coating the iron / titanium layer located inside the silicon dioxide layer, when the complementary color of the preset color in the seven colors under the suspension microscope shows the largest proportion, the coating of this layer is ended; when coating the silicon layer, When the visual color of the suspension is the complementary color of the preset color for the second time, stop the coating of this layer; when coating the titanium / iron layer located outside the silicon layer, when the visual color of the suspension is the preset color, stop the coating of this layer cover. A sufficiently thick silicon layer is set between titanium and iron to avoid the interference color limitation caused by the formation of golden iron titanate. During the hydrolysis coating process, the coating amount is determined by the color of the suspension microscope and visual inspection. The obtained pearlescent pigment has high saturation, good vividness, and a large discoloration range, and it is easy to obtain iron blue pearlescent pigment.

Description

technical field [0001] The present application relates to the technical field of pearlescent pigments, in particular to a production process of color-changing pearlescent pigments. Background technique [0002] Pearlescent pigments are composed of thin layers of several metal oxides coated with mica or glass substrates. The pearlescent pigment made by coating the metal oxide layer on the surface of the substrate, because a part of the incident light is refracted and reflected multiple times, the luster has a depth, thus forming a pearlescent luster. Different pearlescent effects can be produced by changing the thin layer of metal oxide. Compared with other pigments, pearlescent pigments have incomparable effects for their unique soft pearl luster. [0003] The interference effect of pearlescent pigments is directly affected by the thickness of each coating layer. In the existing pearlescent pigment coating process, the thickness is controlled by the coating ratio. Howeve...

AI Technical Summary

Problems solved by technology

However, different batches of raw materials have different diameter-thickness ratios, which directly lead to different specific surface areas, resulting in different total surface areas of raw materials of the same quality. Therefore, different batches of substrates are coated with the same coating rate However, the thickness of the cladding layer obtained is different

Based on this, it can be concluded that determining the coating amount according to the coating ratio cannot obtain an accurate coating thickness, so the interference color effect of pearlescent pigments is difficult to guarantee

[0004] In addition, the existing iron-titanium series pearlescent pigments can only produce golden pearlescent effect, or dark gold or light gold, when iron-titanium composite coating is used; iron-titanium coating can only produce pearlescent pigments close to gold, The discoloration range is from iron yellow to iron red, because iron compounds and titanium compounds will form golden iron titanate in direct contact or contact after migration, so that the color of pearlescent pigments is limited to near gold, and it is difficult to truly reach iron blue

Images