Brief description of digital printing thermal transfer ink index

Thermal transfer has developed rapidly in textile digital printing. At present, compared with active, acid, paint, disperse direct injection and other processes, the amount is larger. Different papers, different printing speeds, and even different fabric uses, all put forward higher demands on ink. requirements, how to evaluate an ink, refer to the following indicators:

One: technical parameters
1. PH value
2. Surface tension
3. Viscosity
4. Conductivity
5. Particle size
The inks for different printhead models are slightly different.

Two: security
1. Transportation
2. Heavy metal
3. Azo
4. AEPO
Testing standards include MSDS, ROHS, REACH, OEKO-TEX100, etc.
Commonly used testing institutions are SGS, ITS, BV, TUV, STR, etc.

Three: performance
1. Dry rubbing fastness can generally reach 4-5 grades. The red color is slightly worse, so some fabrics that are not well-bleached, the red color is easy to fade, on the one hand because of the fabric, on the other hand because of the low red fastness.
2. Wet rubbing fastness, generally can reach 4-5 grades.
3. The fastness to perspiration can generally reach 4-5 grades.
4. Light fastness level, ISO 105-B02, MYK color can reach 6 level, C color is slightly worse than 4-5 level, so long-term exposure, the fabric turns yellow, which is the reason for the cyan fading, to improve the fastness, you need to choose high Sun-tanned cyan.

Brief description of digital printing thermal transfer ink index1

Four: process characteristics
1. Concentration, the higher the concentration, the less ink is used, but the small amount of printing ink will affect the detail performance of the pattern, so some models have developed 6 or 8 colors, adding light colors or spot colors, just to increase the details and color gamut, the concentration should be relatively reasonable.

The general classification of ink is: ordinary density, medium density, high density (dispersed direct injection), high density and quick drying (high-speed machine thin paper scheme) ink, which can meet the needs of different models and different types of fabrics.

2. Fast-drying, good fast-drying type will reduce drying power and reduce workshop temperature, which is a direction of ink development. High-speed machines especially need fast-drying type ink, but fast-drying type may affect the standby performance of the print head.

3. The amount of oil fume, thermal transfer printing does not produce waste water, but a certain amount of oil fume will be generated during the transfer process. Materials such as glycerin have a great impact on this. Reasonable control of oil fume to reduce emissions.

4. Standby, new boot, or under standby conditions, in addition to a good moisturizing device, put forward requirements for ink standby, reduce the number of cleaning nozzles.

5. Fluency, the stability of continuous production is crucial to efficiency and cost. In addition to screening stable raw materials, a good process formula, the matching degree of the machine’s waveform voltage and ink are crucial to the smoothness of printing.


Post time: May-07-2022