Foam printing is a special kind of fabric printing that uses foaming ink to print, that is, foaming ink (printing paste) is used to print on the fabric into a bump, and after baking and heating, the printed pattern is foamed and convex with the ink film. And then naturally cooled and solidified into embossed graphics, making the printing effect full of three-dimensional sense, similar to artificial embroidery, soft to the touch, wear-resistant, washable, good fastness, flexible, with high use value and artistic appreciation value. Screen printing is the most important method of foam printing. The operating methods of each process are as follows:
1. Pattern design
For the original pattern used for foam printing, it is not allowed to use a pattern with too thin lines. Pay attention to this point when printing corduroy. In general, foam printing should use patterns with a line width greater than 0.25 mm and a dot area greater than 0.5 mm2. Because the foaming ink particles are thick, it is easy to block the mesh or cause wire breakage: the dot area is too small, the flash paint bridging is poor, and the fine layer will be lost, resulting in greater graphic distortion: from the pattern design, foaming Printing is not suitable for application on large-area patterns, otherwise it will feel stiff and stiff, and there will be obvious unevenness and bottoming. In the pattern design, the lines and small solid blocks in the overall pattern are suitable for foam printing. In the color matching, the color of the foam printing should be lighter than dark, and can be matched with the ordinary printing. It is better to use the ordinary printing to print the background color, the dark color, and the large area pattern. In addition, the size of the color block of the selected design should be appropriate. If it is too large, it will cause wrinkles or breaks in the middle of the graphic. one slice. And in the corduroy foam printing, because of the influence of factors such as mesh, materials, equipment, etc., the pattern design, pattern arrangement, etc. must also be considered in the pattern design. The fabrics are processed according to the variety of specifications and their post-printing processes And pattern changes, as well as factors affecting the overall effect of corduroy printed products and fabric style. Also, for microcapsule foaming inks, because it is difficult to express the color and gradation of a very rich picture, therefore, try not to choose a picture with a very rich gradation and high definition requirements as the original.
2. Bottom production
Using water-resistant photosensitive adhesive, in order to improve the foaming effect and increase the thickness of the ink layer, the photosensitive film should be thicker (20 ~ 50 microns). The selection of screen mesh should comprehensively consider the characteristics of pattern fineness, block size, foaming ink characteristics, printing process used and corduroy fabric specifications. Since foamed inks are prone to cause clogging, high-mesh screens are not suitable. Generally, 80 to 120 meshes are suitable. In addition, the coarse mesh can increase the thickness of the ink layer and improve the foaming effect. The direct coating film thickness is greater than 8 microns, and the indirect method uses five-star film (average film thickness of 8 to 12 microns) or capillary film with a film thickness of 18 to 50 microns. In addition, in order to ensure that the outline of the pattern during printing is clear and to avoid or reduce the occurrence of three colors (multiple colors), in addition to selecting the appropriate screen mesh, we must also handle the relationship between the colors and the colors in the pattern. Using the dividing line and borrowing technique in the screen making process, as for the method and determining the dividing line distance, it should be considered based on the requirements of the total printing effect, the nature of the color paste, the fabric specifications and other factors.
3. Ink adjustment
The key material in foam printing is foam ink. At present, the foaming ink mainly includes general foaming oil and microcapsule foaming ink.
General foaming ink. Mainly rely on the gasification of the blowing agent to achieve the purpose of foaming. This ink is made by dissolving the foaming agent in liquid polyvinyl chloride resin. When the ink is heated, the foaming agent vaporizes, forming countless tiny pores in the ink layer, and the graphics will foam up. Common formulas are: polyvinyl chloride resin (40.8%), dioctyl phthalate (36.7%), calcium carbonate (18.3%), dibasic aluminum phosphite (2.0kg), azodicarbonate (2.0 kg), coloring pigments (appropriate amount).
Among them, polyvinyl chloride resin: a polymer compound formed by polymerizing vinyl chloride, polymerized into a paste resin by an emulsion method, and used as a binder in foamed inks.
Dioctyl phthalate: It is a colorless transparent oily liquid. It is used as a plasticizer in foaming inks. It has good cold resistance and low volatility. This plasticizer can increase the processing of PVC resin. Plasticity and fluidity during molding.
Fabric Shaver,Portable Fabric Shaver,Electric Fabric Shaver,Battery Electric Fabric Shaver
Ningbo Beilun Xuanfeng Molding Co., Ltd. , https://www.schelfern.com