Power-controlled bonding of resin or (co)polymer powder and flake materials

Abstract

The present invention provides methods of making sticky powder comprising mixing one or more resin or (co)polymer powders in one or more mixing devices without agglomerating the powders and while measuring the power, work or torque drawn by the mixing devices, the mixing continuing until the measure of the power or torque drawn indicates that the powders have become sticky. The mixing further comprises adding to the powders one or more dry materials and mixing to so that the dry materials adhere or ''bond'' to the sticky powders. Alternatively, the methods further comprise slowing or stopping the mixing, or cooling while mixing once the said sticky powders have been formed, adding one or more dry materials to form a sticky powder mixture, and further mixing to bond the sticky powders and the dry materials together.

Description

technical field [0001] The present invention relates to a method of manufacturing cohesive powders and a method of manufacturing powders containing additives or two or more powder materials, more particularly, to manufacturing paint powders containing metal or mica pigments. Background technique [0002] Because powder coatings provide durable coatings with excellent pigment control, powder coatings have been marketed with increased metallic or non-metallic flake content to provide highly reflective metallic-look coatings, or to provide shiny topcoats. In decorative coatings, glitter effects are achieved by metallic coatings. Highly reflective coatings provide visibility and easy identification of objects. Metallic coatings can be used to reduce container temperature, provide solar reflection, etc. Similarly, it is advisable to add non-metallic flakes such as mica to powder coatings to produce unique appearance effects. However, coating powders containing metal flakes are...

AI Technical Summary

Problems solved by technology

However, when the melt-blended composition is ground to make a paint powder, the flakes are easily broken, and the appearance of the topcoat obtained from such a paint powder is dull gray

Likewise, coating powders in which aluminum flakes were embedded in the powder by grinding, such as in a ball mill, contained significantly broken flakes, and the resulting coatings did not achieve a gloss comparable to solvent-based metallic paints

However, the brushing method cannot produce paint powders on any industrial scale