Sublimation transfer printing appeared in the 1930 s, popular in Europe and the United States and Japan in the 70 s countries, from the point of historical data, its development is special, surprised many people, neither as optimists predict with absolute market share in the textile printing, also do not have as pessimists say, slow development, stagnation, even decline. However, thermal sublimation transfer technology is developing rapidly in our country, and the application field is very extensive. In addition, due to the lack of investment equipment, the printing effect is prominent, pollution-free, saving resources and other reasons, the relevant government departments attach great importance. At present, sublimation transfer printing technology in our country has been listed in the state economic and trade commission key industry clean production technology oriented directory (first batch) 45, prospect of application in our country has a huge space for development.

I. process principle and characteristics.

Thermal sublimation transfer printing first USES the printing method to print the special printing dye to transfer paper, then heat, pressure, transfer the dye to the fabric. In particular, it is according to the properties of disperse dye sublimation, choose sublimation temperature range is 180 ~ 240 ℃ of disperse dye, mix it with slurry made from the color, according to the requirements of the different decorative pattern, design, use Ep ~ J, the way to the color printing on the transfer paper, transfer paper will be printed with decorative pattern, pattern and fabric close contact, in 200 ~ 230 ℃ on the transfer printing machine processing 10 ~ 30 s, dye transfer printing paper to fabric, through the internal diffusion into the fabric, achieve the goal of coloring. In the process of heating and sublimation, in order for the dye to be directed diffusion, it is often to draw a vacuum at the bottom of the substrate to achieve the directional diffusion transfer and improve the transfer quality.

At present, the real large-scale technology for commercial and industrial digital printing is mainly thermal sublimation transfer printing technology. As domestic has introduced price advantage of the sublimation ink (main heat sublimation transfer printing ink expensive imported from South Korea and Italy), and the digital printing technology, thermal sublimation transfer printing technology applications become more extensive. In conclusion, thermal sublimation transfer technology has the following four aspects:

1. Good printing effect.

Adopting the heat sublimation transfer printing technology printed fabric pattern, bright colors, rich layers, clear, and high artistic quality, stereo sense is strong, is a common method of printing is accomplished very hard, and can be printed pattern of photography and painting style.

2. Soft touch and long service life.

The biggest characteristic of heat sublimation transfer is that the dye can be diffused into polyester or fiber, and the printing touch is very soft and comfortable, and the ink layer can hardly be felt. In addition, since the ink is drying in the process of printing, the life of the image is as long as the life of the garment itself, and the wear and tear of the printed text will not appear, which will affect the aesthetics of the fabric.

3. Simple process, less investment in equipment, strong flexibility and high yield.

The heat sublimation transfer can be an Ep~J at one time, and it can be printed in a short time to meet the personalized needs of the customers according to the personalized needs of the customers.

4. Save resources and protect the environment.

Unlike traditional fabric printing, thermal sublimation transfer printing does not need to be steamed, washed and other post-treatment processes, saving a lot of water resources and no sewage discharge, which can save resources and protect the environment.

Ii. Factors affecting the quality of sublimation transfer.

1. Ink

Thermal sublimation transfer ink is a key material for sublimation transfer technology, which consists of disperse dyes, linings, solvents and a few additives. Dye requires a good sublimation transfer resistance and permeability, has achieved the fastness, molecular weight of 230 ~ 380, sublimation temperature is 180-240 ℃, the commonly used transfer printing dye is anthraquinone dyes, azo dye and cationic dye, etc. Connected to the material requirements and dye affinity is small, easy to release the dye gas, and has the appropriate printing adaptability, save and adaptability of thermal transfer, commonly used connection material for low viscosity ethyl cellulose, ethyl hydroxyethyl cellulose (EHEC), long oil modified alkyd resin, etc. The commonly used solvents are turpentine, oil alcohol, high boiling point alkanol, aromatic alkanes, soluble fiber, etc. Is the biggest characteristic of heat sublimation transfer printing dye can be spread to the textile fiber, the fiber and fabric fixation is good, therefore, the thermal sublimation ink color is clear, with good quality stability is strong, the transfer effect is good.

Sublimation transfer printing appeared in the 1930 s, popular in Europe and the United States and Japan in the 70 s countries, from the point of historical data, its development is special, surprised many people, neither as optimists predict with absolute market share in the textile printing, also do not have as pessimists say, slow development, stagnation, even decline. However, thermal sublimation transfer technology is developing rapidly in our country, and the application field is very extensive. In addition, due to the lack of investment equipment, the printing effect is prominent, pollution-free, saving resources and other reasons, the relevant government departments attach great importance. At present, sublimation transfer printing technology in our country has been listed in the state economic and trade commission key industry clean production technology oriented directory (first batch) 45, prospect of application in our country has a huge space for development.

I. process principle and characteristics.

Thermal sublimation transfer printing first USES the printing method to print the special printing dye to transfer paper, then heat, pressure, transfer the dye to the fabric. In particular, it is according to the properties of disperse dye sublimation, choose sublimation temperature range is 180 ~ 240 ℃ of disperse dye, mix it with slurry made from the color, according to the requirements of the different decorative pattern, design, use Ep ~ J, the way to the color printing on the transfer paper, transfer paper will be printed with decorative pattern, pattern and fabric close contact, in 200 ~ 230 ℃ on the transfer printing machine processing 10 ~ 30 s, dye transfer printing paper to fabric, through the internal diffusion into the fabric, achieve the goal of coloring. In the process of heating and sublimation, in order for the dye to be directed diffusion, it is often to draw a vacuum at the bottom of the substrate to achieve the directional diffusion transfer and improve the transfer quality.

At present, the real large-scale technology for commercial and industrial digital printing is mainly thermal sublimation transfer printing technology. As domestic has introduced price advantage of the sublimation ink (main heat sublimation transfer printing ink expensive imported from South Korea and Italy), and the digital printing technology, thermal sublimation transfer printing technology applications become more extensive. In conclusion, thermal sublimation transfer technology has the following four aspects:

1. Good printing effect.

Adopting the heat sublimation transfer printing technology printed fabric pattern, bright colors, rich layers, clear, and high artistic quality, stereo sense is strong, is a common method of printing is accomplished very hard, and can be printed pattern of photography and painting style.

2. Soft touch and long service life.

The biggest characteristic of heat sublimation transfer is that the dye can be diffused into polyester or fiber, and the printing touch is very soft and comfortable, and the ink layer can hardly be felt. In addition, since the ink is drying in the process of printing, the life of the image is as long as the life of the garment itself, and the wear and tear of the printed text will not appear, which will affect the aesthetics of the fabric.

3. Simple process, less investment in equipment, strong flexibility and high yield.

The heat sublimation transfer can be an Ep~J at one time, and it can be printed in a short time to meet the personalized needs of the customers according to the personalized needs of the customers.

4. Save resources and protect the environment.

Unlike traditional fabric printing, thermal sublimation transfer printing does not need to be steamed, washed and other post-treatment processes, saving a lot of water resources and no sewage discharge, which can save resources and protect the environment.

Ii. Factors affecting the quality of sublimation transfer.

1. Ink

Thermal sublimation transfer ink is a key material for sublimation transfer technology, which consists of disperse dyes, linings, solvents and a few additives. Dye requires a good sublimation transfer resistance and permeability, has achieved the fastness, molecular weight of 230 ~ 380, sublimation temperature is 180-240 ℃, the commonly used transfer printing dye is anthraquinone dyes, azo dye and cationic dye, etc. Connected to the material requirements and dye affinity is small, easy to release the dye gas, and has the appropriate printing adaptability, save and adaptability of thermal transfer, commonly used connection material for low viscosity ethyl cellulose, ethyl hydroxyethyl cellulose (EHEC), long oil modified alkyd resin, etc. The commonly used solvents are turpentine, oil alcohol, high boiling point alkanol, aromatic alkanes, soluble fiber, etc. Is the biggest characteristic of heat sublimation transfer printing dye can be spread to the textile fiber, the fiber and fabric fixation is good, therefore, the thermal sublimation ink color is clear, with good quality stability is strong, the transfer effect is good.

At present, the sublimation ink is divided into water-based and solvent-based two kinds, most of the sublimation is water-based ink, water-based heat sublimation ink can be used in all sorts of small wide desktop printers and large-format photo machine, the solvent thermal sublimation ink is mainly used in wide spraying machine, solve the problem of inkjet printing speed and width. The quality of the hot sublimation ink directly affects the Ep~J of the product. Therefore, it is very important to select high quality hot sublimation ink.

2. The time

Thermal sublimation transfer printing technology is to control the temperature of 180 ~ 230 ℃ range, transfer time is about 1 o - 30 s, but also pay attention to the temperature and the reasonable allocation of time.

3. The pressure

Pressure is also one of the important parameters of heat sublimation transfer printing technology, the sublimation transfer printing fabric, for example, if the pressure is too small, big gap between fabric and transfer paper, yarn assumes the circular, ink gas molecule collisions with a lot of air and dissipation, leading to poor Ep ~ J effect, also easy to ink bled, line coarsen and decorative pattern design, fuzzy, visual effect is worse; If the pressure is appropriate, the yarn is flat, and the space between the fabric and the transfer paper is suitable for the transfer of color, the pattern is clear, the lines are smooth and fine; If the pressure is too high, it is easy to produce deformation, hair and heavy fabric changes in shape, resulting in rough and stain surface and other shortcomings. In this way, it is very important to control the improvement of printing pressure on the beautiful fabric with clear visual effect. At present most of the manufacturers of hot stamping machine pressure adjustment is very convenient, in the actual production process, the operator shall conduct detailed records of process parameters, looking for all kinds of products the best transfer printing pressure, effective guidance to the subsequent production and processing.

4. Other

In addition to the ink, temperature, time and pressure, which can affect the quality of the sublimation transfer, there are some important points to pay attention to during the actual production and production process. Firstly, it is the selection of the transfer paper, the quality is stable, and the supplier with high credibility should be the first choice for the printing enterprise. Secondly, to recognize the dye ink before transfer (heat pressing design) on the transfer paper before and after the transfer printing, transfer printing fabric design) on the color difference is very big, dye ink generally look darker and lacklustre before transfer, relying on the high temperature of 200 ℃ or so restore color, so, proofing is necessary before printing production; Finally, when the heat transfer, make sure that the hot pressing surface, the transfer paper and the substrate surface close together, there is no space, otherwise the possible transfer of the blurred image.

Technological breakthrough.

1. No version of the

At present, gravure printing is one of the main methods of thermal transfer paper printing, the printing method has the advantage of simple models, designs the transition level nature, stereo sense is strong, the disadvantage is that plate making expensive (per the cost of registering the base for RMB 3000-5000), the production cycle is long, don't adapt to the personalized, small batch, there is a wide selection of products. In order to reduce the cost of plate making, save cost, use offset printing, screen printing, flexo printing instead of gravure to become a majority of manufacturers. With the advent of the digital age of printing, the thermal sublimation transfer is developing towards the digital version, and the thermal sublimation inkjet printing technology makes the transfer printing of thermal sublimation to be unversioned. The sublimation inkjet printing technology refers to the use of small desktop inkjet printer or large-format inkjet pictorial machine or wide spraying machine, through heat and heat sublimation transfer paper, sublimation ink transfer patterns or images printed or directly spray on the material, with thermal transfer machine or solid color solid color processing, realize the sublimation transfer printing. This technology because of the need not spend a lot of time making plate, make the production cycle is greatly shortened, and cost savings, it is widely used in strong personalization, small batch products printing, such as t-shirts, uniforms, advertising banners, mouse pads, mugs, carpet of heat sublimation transfer printing, etc.

2. The paperless

Related professionals in transfer printing technology has been a breakthrough for many times, donghua university, college of chemistry and chemical technology experts using disperse dye microcapsules technology to transfer printing was studied, using the microcapsule technology will disperse dye, microcapsule dyes as a small warehouse, controlled release properties is slow no paper thermal transfer printing transfer printing is the most distinct characteristics of base material can be reused. It first make dye printing paste, and then through the way of printing will be printed pattern on a special base material, and then with fabric after hot spots, the pattern of base material will be transfer and fixation on the fabric, printing the finished product can be obtained directly. Traditional transfer printing technology requires a lot of expensive transfer paper, and adopt the new base material no paper thermal transfer technology is eliminating the cost of transfer paper, save cost, but also caused by paper and waste paper from the water consumption and wastewater emission problems, not only saving the water resource more to protect the ecological environment.

Paperless heat transfer printing process can print patterns, patterns, and can transfer patterns, pattern heat transfer to the fabric, and after the heat transfer, can be reused, basically no loss. Therefore, the transfer printing paperless development trend is good, paperless technology will also achieve a bigger breakthrough.

3. Reuse

The heat transfer printing paper containing the information of the text can only be transferred once. Once the information is transferred to the final substrate, the function can not be transferred again. To this end, the study of multiple transfer printing technology, control the release of dye on the heat transfer printing paper, and make the color dye quantitative transfer, to achieve multiple transfer printing has become the subject of many scientific research institutions. Multiple transfer printing can effectively use the relatively expensive thermal transfer paper, greatly saving the transfer cost. Domestic release, when each transfer, it releases a certain amount of dye, to achieve a constant color multiple transfer effect, so as to achieve the purpose of multiple transfer.