Study on preparation and application of dot-patterned powder coating

Study on preparation and application of dot-patterned powder coating

Gao Jiantuan Yu Jia (Wuhan Yincai Technology Co., LTD.)

Abstract: Dot-pattern powder coatings, renowned for their diverse color palettes, layered textures, vivid hues, and sophisticated appearance, are extensively utilized in surface decoration applications such as premium profiles, hardware furniture, crafts, and marble-effect finishes. These coatings combine superior physical properties with decorative appeal, making them a market hotspot. Early dot-patterned powder products faced challenges in particle size distribution,

Issues such as inconsistent density and electrostatic properties often lead to problems like uneven surface distribution (sparse upper points vs. dense lower points), poor powder reusability, and compromised construction quality, significantly reducing material efficiency and hindering large-scale adoption. Drawing from years of practical experience in producing dot-pattern powder, this article elaborates on raw material selection, preparation techniques, and application guidelines for dot-patterned powder. By facilitating knowledge exchange among powder industry professionals, we aim to enhance both product quality and construction stability in dot-pattern powder applications.

Key words: dot-pattern; powder coating; preparation process; construction application; quality control

I. Introduction

Powder coatings originated in Europe in the 1950s. In their early stages, due to immature technology, inadequate supporting equipment, and high costs, only epoxy-based coatings could be produced, primarily used in military applications. By the 1960s, the emergence of electrostatic spraying technology accelerated the commercialization of powder coatings. In the 1970s, powder coatings entered the Chinese market. With their convenient application, environmental friendliness, and excellent coating performance, they gradually found widespread use in hardware, home appliances, automotive, structural materials, medical equipment, pipeline corrosion protection, and general industrial applications. Depending on the application environment and coating form, powder coatings can be categorized into indoor corrosion-resistant types and outdoor weather-resistant types. Their surface effects include various patterns such as flat, sand-textured, corrugated, velvety, turtle-shell, snowflake, and speckled designs. Dot-pattern powder coatings have gained increasing market favor due to their unique decorative effects.

The production of dot-pattern powder requires strict control of raw materials and process parameters to ensure that the final product has good construction adaptability and visual effect. This paper focuses on the key technology and matters needing attention in the production of dot-pattern powder.

II. Key points of pollen preparation

2.1 The base powder should be selected with low viscosity and high flow resin, so as to facilitate the expansion and formation of the dot-pattern;

2.2 The dosage of dot-pattern agent should be adjusted according to the size of dot: more dot-pattern agent should be added for large dots, and less dot-pattern agent should be used for small dots;

2.3 Different specifications of sifters can be used to control the uniformity and fullness of dot-pattern;

2.4 It is recommended to use medium hydroxyl polyurethane resin as the dot-pattern resin to enhance the embedding and diffusion of dot-pattern.

III. Dot-pattern powder preparation techniques

3.1 The base powder sifter should be selected as 160 mesh; for large dot, double-layer sifter of 80-120 mesh can be used to take the middle particle size part, and for small dot, it is recommended to use 100-160 mesh sifter in the middle part to ensure uniform particles;

3.2 Weigh the base powder and dot-pattern agent accurately in proportion;

3.3 Put the base powder into the mixing tank;

3.4 The dot-pattern agent is mixed with a small amount of base powder in advance and then put into the mixing tank for mixing;

3.5 When spraying, the spray gun should keep moving up and down at a uniform speed, the nozzle is about 5 cm above the upper edge of the sample, and the lower edge is aligned with the sample;

3.6 It is recommended to spray large size test plate for color and effect confirmation, and then the material can be placed, packed, weighed and stored in the warehouse.

IV. Typical formula examples

4.1 Base powder formula:

Table 1: Composition of base powder formula

4.2 Formula A:

Polyurethane (industrial grade, DSM), dot-pattern agent (industrial grade, Tianlong), wax powder (industrial grade, YinCai), pigment (industrial grade, Bayer)

4.3 Formula B:

            Polyurethane (industrial grade, DSM), dot-pattern agent (industrial grade, Tianlong), wax powder (industrial grade, YinCai)

V. EFFECTS SHOWN

VI. CONCLUSIONS

The production of dot-pattern powder coating requires comprehensive consideration of raw material characteristics, process parameters, and construction conditions. By optimizing sifter selection, dot-pattern agent dosage, and mixing processes, product consistency and construction adaptability can be significantly improved, promoting its wider application in high-end decoration fields.