Thermoset ink introduction and operation method

Thick screen printing has become a popular trend in T-shirt clothing and handbag printing. Because thermosetting inks are non-solvent inks, they have the advantages of non-drying, odorless, high solids content, good squeegee flowability, and can be printed by hand or fully automated. Therefore, screen printing manufacturers prefer to use thermosetting inks. The ink is thick-printed. Thick inks have high hiding power spot colors, translucent, transparent and other types. There are right angles, rounded corners, and special effects formed with different printing processes.

First, the choice of solid ink

Most brands of thermosetting inks have a drying temperature and time of 180 degrees. Many substrates and fabrics cannot withstand the high temperatures and cause yellow discoloration or deformation. The use of FD series low temperature thick thermosetting ink can overcome the above deficiencies. Its characteristics: ink smooth, good fluidity, easy to print over the net, can print fine lines, and the surface is smooth, good fastness, high ink solid content, without thick foam components, after 140 ~ 160 degrees Curing between 2 and 3 minutes, and the pattern does not deform. (Heat-solid ink drying on the surface of the hair dryer can not produce real fastness or non-uniformity. The print must be dried in infrared oven at 140-160 degrees for 2 to 3 minutes to cure evenly. The drying temperature and time are only For reference, the temperature of the ovens of different manufacturers may not be the same, and the proper temperature and time should be set according to the performance of the oven itself.The ink is flexible after being cured, the surface cannot be powdered, and the scraping is not bad; otherwise, the plasticization temperature is not enough. The need to properly increase the plasticization temperature and time.Drying temperature of more than 220 degrees may cause print surface blisters.

Second, the ink deployment method

1. Blending high hiding power spot color thick ink: Add the desired color to the white to adjust the depth.

2. Choice of translucent hue thick printing ink selection: FD series transparent ink 90%, color shade degree is determined by adding color proportion.

3 The viscosity of the ink is too high (too thick). 1 to 5% of diluted water can be added to make the ink more suitable for application viscosity.

Note: To clean the screen of printing thermosetting inks, use turpentine water or printing water (this solvent can not be used as a diluent to mix thermosetting ink, otherwise the ink will deteriorate).

When printing with a thick screen, the printing plate needs to be made of a thin one and a thick two screens: a thin screen plate with a film thickness of 0.2 mm for the bottom printing; a thick screen plate with a film thickness of about 0.5 to 0.7 mm, For thick printing. Slant-stretching can be used to make thicker lines more legible. If the screen-stencil is more than 0.7 mm in thickness, although it is easy to reach the print thickness, squeezing thin lines can result in uneven line edges.

Selecting a special photopolymer for sun-thick printing, the solid content is high and the resolution is high, which helps the formation of a thick film, and the dried screen lines are neat and clear. The method of coating the photosensitive resin: First, apply a photo-sensitive adhesive on the squeegee and the bottom, and then dry it. Then apply the photo-sensitive adhesive on the bottom surface several times and dry it until it reaches a certain thickness and then print. If you want to quickly increase the thickness of the stencil coating, you can place a steel ruler on the left and right sides of the stencil sheet, stick it with adhesive tape, and then apply the sensitized adhesive. Due to the height of the steel ruler, the sizing agent naturally produces thickness when the sensitized adhesive is applied. After coating the photosensitive resin and drying the screen with a hair dryer, it is necessary to constantly move the photosensitive paste to the heated position. Otherwise, the photosensitive paste may be overheated due to overheating, which will result in aging of the photosensitive paste and inability to print.

Usually a thick plate of 0.7mm requires a 4000 W iodine lamp or halogen lamp for one-time exposure. If the 2000 W version of the printing lamp can only print 0.4 mm thick film at a time, and printing with a 2000 W copying lamp, there are two disadvantages: (1) the original line will be thin; (2) right angle degree influences.

Therefore, in the thick version of the artwork to be made when the expansion of adjustments: (1) the original size of the original artwork; (2) thick version of the artwork to expand 0. 1 ~ 0.3 mm (specific expansion depends on the thickness of the film, lines The thickness may be determined).

The thick screen version can refer to the above specific requirements. According to its own supporting tools for printing, it can be better adjusted during operation.

Fourth, the choice of scraper

Heat transfer | printing | color separation | printing technology exchange selection of polyurethane flat blade, scratch type scraper is recommended. It should be noted that the appropriate scraper should be used when printing. The stiffer or softer scraper will lead to defects such as thin ink layer, unclear lines and poor smoothness. In addition, the size of the squeegee pressure should be mastered during printing to achieve the best results.

Fifth, screen printing process

Heat transfer |printing |color separation |printing technology exchange The same type of thick ink or paste using different printing methods produced different fastness, the following two printing methods for comparison: (1) selection of thick screen printing ink After repeated printing and drying, the required thickness of the printed product can be achieved, but the firmness of this printing method is deviated because the contact area between the ink and the fabric is not enough; (2) Each thin plate should be prepared with a thin net. The printing is used as a base printing so that the ink layer can penetrate into the fabric fibers, and then repeat printing and drying with a thick printing ink until the desired thickness is reached. This printing method can achieve the best fastness of the ink.

Heat transfer | printing | color separation | printing technology exchange spot color ink or transparent ink used in the bottom printing must be diluted with 5~8%~ dilute water, so that the primer ink can penetrate into the fabric fibers, so as to achieve The best firmness. A total of 2 or 3 printings are made at the end of the printing process, each time it is scraped with 2 knives; the first 2 printings are done with 70% dryness; the 3rd printing is still scraped with 2 knives without drying, and then the FD series thick printing ink is overprinted and the printing is repeated. With drying until the desired thickness is reached. In general, thick prints have to be made more than 6 times to reach the desired thickness.

FD series inks are used to print thick prints on leather. Because leather is a flat substrate, there is no need to make a bottom print. Repeated printing and drying can be performed directly with a thick plate to achieve the desired thickness.

Six, thermosetting thick printing and hot foil process

Prepare 2 silicone plates and 1 heat transfer machine first. According to the above-mentioned method of printing thermosetting inks, after printing the desired thickness, the last printing does not need to be dried, wet the foil and flatten it on the pattern, and then blow the hot foil with a hair dryer to make the foil foil with the ink. The surfaces are fused together and then oven-dried at 140-160 degrees for 3 minutes. Hold the prints on a silica gel plate and cover the other foil with a hot stamping foil. Then use a heat transfer press for a cold press for 7 seconds. Tear off after cooling. (The quality of hot stamping foil will directly affect the product. firmness).

Seven, transfer heat transfer

Heat Transfer | Printing | Separation | Printing Technology Communication According to the method of thermosetting ink mentioned above, the ink is first printed on the transfer paper. After the print has reached the required thickness, only the pattern of the transfer paper is placed. On the surface of the fabric (distribution sheet) or the transferred object, and then ironed with a heat press (or iron) for a few seconds, the pattern is directly transferred to the object. (Applicable to nylon chemical fiber, umbrellas, windbreaker, neon, socks, PU, ​​leather, etc.) Transfer temperature: 140-160 degrees, time 6-8 seconds; tearing method: Cold tearing.

FD-502 round transparent thermosetting ink is suitable for bonding plastic beads. Adhesion fastness to wet cleaning, dry rub up to 4 or more. (Washing machine 45 degrees continuous washing for 10 hours does not fall off!) FD-502 printed on the cloth and dampened with plastic beads, 160 degrees drying or pressing machine 150 ~ 160 degrees pressure 8 ~ 15 seconds.