Paperless thermal transfer printing technology question and answer

Q: What are the traditional textile printing methods?

A: At present, there are mainly two kinds of printing methods for textile fabrics: screen printing and thermal transfer printing.

Screen printing also includes lithographic printing and rotary screen printing. Its working principle is to coat the unpatterned part of the mesh according to the pattern, forming a pattern composed of meshes, and directly printing the color paste on the fabric through the pattern mesh to complete the fabric. Printing process. The patterned fabric is then steamed, fixed, soaped, and washed to give a finished product. This kind of printing method is very mature both in terms of technology and equipment, and the production capacity can reach 60 meters/minute. The main drawback of screen printing is the large amount of water consumed (3~5m3/100 meters of cloth), which will generate a lot of sewage.

Thermal transfer printing is a water-saving printing and dyeing new process developed in the 1960s and has been industrialized. The process is to make the dye into ink, and then print the thermal transfer printing paper, and then affixed with the front of the cloth, press for a few seconds at a certain temperature and pressure, the pattern on the paper is transferred to the fabric. The printed cloth thus printed does not need to be steamed, soaped and washed, so the printing process does not consume steam, coal or water, nor does it produce sewage. However, there are still two major problems in this process: one meter of paper is needed for printing 1 meter of cloth, which not only consumes cost, but also indirectly consumes water and water pollution; polyester fabrics can only be printed, and the application area is limited.

Q: What is paperless transfer printing? What is the difference with traditional printing methods?

A: No paper thermal transfer printing First, the dye is made into printing paste. The pattern is printed on a special substrate by printing. Then it is pasted with the fabric through the hot zone. The pattern on the hot zone substrate It is transferred to and fixed on the fabric to obtain a printed product. Among them, the substrate can be reused.

The main features of the paperless thermal transfer printing process include: no need for steaming, soaping, and water washing, no consumption of steam, coal, water, no sewage in the printing process, no paper consumption, no indirect consumption due to paper consumption Water consumption and water pollution; the printed patterns are delicate, clear, rich in layers and natural, capable of printing products similar to photographs and painting styles.

Q: What are the advantages of paperless transfer printing?

Answer: The outstanding advantage of the paperless thermal transfer printing process is to save energy from the source, especially the very precious water resources, and it is in line with the country's strategy for sustainable development.

Nearly 50% of the cost of the printing and dyeing process is the consumption of energy. Saving energy means reducing the production cost, and it can produce high-grade products that are difficult to produce in the traditional printing process.

Q: What are the working principles and varieties of bridging agents?

A: Natural fibers such as cotton are hydrophilic, and the disperse dyes that can thermally transfer flowers are hydrophobic and the two are difficult to bond, so natural fabrics cannot be directly transferred by heat transfer. One end of the bridging agent can be combined with the fiber, and the other end can be combined with a disperse dye, that is, a bridge is established between the disperse dye and the natural fiber, thereby achieving thermal transfer printing of the natural fiber fabric.

There are currently 3 types of bridging agents used for pure cotton, polyester cotton and silk.

Paperless thermal transfer printing machine

Q: How feasible is the technology industrialized?

A: The prototyping of the paperless thermal transfer printing machine is the core link of whether the process can be industrialized. All possible problems and problems that have been considered in advance must be solved one by one. New problems found in machine amplification must also be solved. Research solutions are the only way to ensure the successful trial production of industrial machines.

At present, the prototyping of the paperless thermal transfer printing machine is nearing the end. The successful trial production of the prototype proves that the industrialization of the paperless process has practical feasibility.

Q: What is the development trend of the paperless transfer printing market?

A: The paperless heat transfer printing process was proposed by the research team of the Beijing Institute of Clothing Technology. After nearly 10 years of research, and under the support of the National “15th Five-Year Plan” 863 Program, after three years of research, it has achieved no paper. The breakthrough in machine development has laid a good foundation for the success of the paperless process. Presumably, the future development trend will be more optimistic.