Hot melt powder knowledge summary
Hot-melt powder for clothing generally refers to tpu polyurethane-based adhesives. The melting point is generally around 110 degrees Celsius. This temperature will melt the powder from particles into a gel.
The difference between traditional hot melt powder and digital heat transfer powder:
1. Traditional heat transfer does not need to be melted into digital heat transfer. The main reason is that the glycerin and water contained in the ink used in traditional heat transfer are not so large, and digital heat transfer needs to be fully dried, otherwise oil will return.
2. The traditional hot-melt powder particles are relatively large, that is, the coarse powder in the current digital heat transfer powder, with an approximate size of 120-250 microns. The digital heat transfer powder particles generally use more medium powder and fine powder, and the fine powder particles are generally In 80-160 microns, the size of the medium powder is 100-200 microns, the larger the particle size, the better the fastness, and the hand feeling is hard.
3. The ingredients are slightly different. Traditional heat transfer powder can be selected to add powder with different ingredients according to needs to achieve different fastness, hand feeling and tensile force; digital heat transfer powder is mainly high-purity tpu powder, pure tpu powder is comprehensively speaking of hand feel, fastness, The tensile force is more average, which meets the needs of most scenarios; some mixed powders in the market are used for heat transfer to reduce costs or achieve specific effects, but there will be problems in different degrees, such as poor fastness with good hand feel , weak covering power, easy to leak, or mixed with other cheap powders, it will feel hard and easy to crack.
How to distinguish the quality of hot melt powder:
1. Look at the color. The higher the color transparency and whiteness, the better, indicating that the purity is better. If it turns yellow and gray, it may be returned powder or mixed powder, which will lead to poor hand feel, easy to break, and pores.
Comparison of the two powders:
2. Look at the surface flatness after drying. The better the flatness, the purer and the better the tensile force.
3. Look at the degree of stickiness during the printing process. The more sticky the powder is, the worse the quality of the powder will be. It will be damp or returned to the oven or there will be a lot of miscellaneous powder.
4. After hot stamping, pull and rub hard to see the resilience, the resilience is faster, the purity is preferred, and the purity is high.