What does digital printing thermal transfer color fastness level 4-5 mean?

Digital printing thermal transfer color fastness level 4-5 refers to the evaluation standard of the washing resistance, friction resistance and other properties of thermal transfer printing on textiles under specific test conditions. Color fastness is one of the important indicators to measure the quality of printing, which reflects the durability and permanence of printing in actual use. The following is a detailed introduction and explanation of thermal transfer color fastness level 4-5:
Definition of color fastness
Color fastness refers to the ability of printed or dyed textiles to maintain color when affected by external factors (such as washing, friction, light, etc.). The level of color fastness directly affects the service life and aesthetics of textiles.
Rating standard for color fastness
Color fastness is usually rated according to level 4-5, with level 5 being the lower and level 6 being the highest. Level 4-5 color fastness means that after a certain number of washing or friction, the color change of the printing is very small, and it hardly affects the appearance.
Thermal transfer technology
Thermal transfer is a printing technology that transfers images or patterns to textiles through heat and pressure. It has the characteristics of bright colors, clear patterns, and soft touch, and is widely used in clothing, home textiles, shoes and hats and other fields.
Factors affecting the color fastness of thermal transfer
Ink quality: High-quality ink has better color fastness and can ensure that the color of the print does not fall off during washing and friction.
Transfer paper quality: The quality and coating of the transfer paper will also affect the color fastness. Good transfer paper can better transfer ink and improve the adhesion of the print.
Transfer temperature and pressure: Appropriate transfer temperature and pressure can ensure that the ink fully penetrates into the fiber and improves the color fastness.
Pretreatment and post-treatment: Appropriate pretreatment (such as cleaning, softening, etc.) and post-treatment (such as shaping, color fixing, etc.) of textiles can improve color fastness.
Textile material: Different textile materials have different effects on color fastness. For example, the color fastness of natural fibers such as cotton and linen is usually higher than that of chemical fibers.
Color fastness test method
Washing color fastness test: Put the printed textiles into the washing machine, wash them according to the standard washing procedure, and then evaluate the color change.
Rubbing color fastness test: Use a friction test instrument to perform dry and wet friction on the printed textiles to evaluate the color shedding.
Light color fastness test: Expose the printed textile to a specific light source and evaluate the color change after a certain period of time.
Perspiration color fastness test: Simulate the effect of human sweat on printed textiles and evaluate the color change under the action of sweat.
The significance of color fastness level 4-5
Thermal transfer printing products that achieve color fastness level 4-5 mean that they can maintain their beauty and durability for a long time under normal use and maintenance conditions. This is an important purchasing consideration for consumers and the key for producers to improve product competitiveness.
Thermal transfer color fastness level - is an affirmation of the quality of printed products, which reflects the strict requirements for material selection, process control and post-processing in the production process. By continuously improving color fastness, the market competitiveness of products can be enhanced and consumers' demand for high-quality textiles can be met.