The traditional printing process includes four processes: pattern design, vase carving (or screen plate making, rotary screen making), color paste preparation and pattern printing, and post-treatment (steaming, desizing, washing).

Pattern design

1. Grasp the style, color and pattern of the pattern according to the use of the fabric (such as men's clothing, women's clothing, ties, scarves, etc.).

2. It is in harmony with the fabric material style. For example, the fineness and color purity of silk products and hemp products are very different.

3. The expression technique, color matching and pattern structure of the pattern should meet the printing process, the width of the fabric, the direction of the silk thread, the clothing cutting and sewing and other factors. In particular, different printing methods have different pattern styles and performance techniques. For example, the number of color sets for roller printing is 1 to 6, and the pattern size is limited by the roller size; The number of color sets for screen printing can reach more than 10, and the arrangement cycle is large enough to print a single fabric, but it is not suitable for designing neat and regular geometric patterns.

4. Pattern style design should consider market and economic benefits

Flower tube carving, screen plate making, round screen making

The flowerpot, screen and rotary screen are special equipment for printing process. In order to make the designed pattern produce the corresponding pattern on the fabric under the action of color paste, process engineering such as flowerpot carving, screen plate making and rotary screen making should be carried out to form the corresponding pattern model.

1. Flower tube carving: the printing and pattern of the roller printing machine are carved on the copper flower tube, with twill lines or dots inside for storing color paste. The process of carving concave patterns on the surface of copper rollers is called flower tube carving. The flower tube is made of iron hollow roll plated with copper or cast with copper. The circumference is generally 400~500mm, and the length depends on the range of the printing machine. The pattern carving methods include manual carving, copper core carving, minitype carving, photographic carving, electronic carving, etc.

2. Screen plate making: corresponding screen shall be made for flat screen printing. Flat screen plate making includes making screen frame, stretching screen and screen pattern. The screen frame is made of hard wood or aluminum alloy material, and then a certain specification of nylon, polyester or silk fabric is tightened on the screen frame to form the screen. The screen pattern is usually made by photosensitive method (or electronic color separation method) or paint proof method.

3. Rotary screen production: Rotary screen printing needs to be made. First, make the nickel mesh with holes, and then cover the two ends of the nickel mesh with a round metal frame to tighten the nickel mesh. Then, apply photosensitive glue on the nickel mesh, tightly wrap the color separation sample piece of the pattern on the nickel mesh, and use the photosensitive method to form a round mesh with patterns.

Color paste preparation and pattern printing IV. Post treatment (steaming, desizing, washing)

After printing and drying, steaming, color development or color fixation treatment is usually carried out, followed by desizing and water washing to fully remove the paste, chemicals and floating color in the color paste.

Steaming is also called steaming. After the printing color paste is dried on the fabric, in order to transfer the dye from the color paste to the fiber and complete certain chemical changes, it is generally necessary to steam. In the steaming process, the steam first condenses on the fabric to raise the temperature of the fabric, swell the fibers and pastes, dissolve the dyes and chemicals, and some react chemically. At this time, the dyes are transferred from the color paste to the fibers, thus completing the dyeing process.

In addition, due to the existence of paste, the dyeing process of printing dyes is more complex, and the steaming time is longer than that of pad dyeing in dyeing. The steaming conditions also vary with the properties of dyes and fabrics.

Finally, the printed fabric should be fully desized and washed to remove the paste, chemical reagents and floating colors on the fabric. The paste remains on the fabric, making the fabric feel rough. The residual floating color on the fabric will affect the brightness and color fastness.