Introduction of aqueous binder for water based pigment paste of textile screen printing

When we use water based pigment paste for textile screen printing, the matched adhesive is necessary. The role of adhesive is adhesion between water based pigment paste and textile fibers. To reach higher quality of pigment printing effect, we have to use adhesive, and make it form a soft and thin film of resin, colorless, non-stick, firmly attached to the textile fibers, good sunlight fastness and dry washing resitance, no rough hand feeling.

During the drying process of textile pigment paste printing, the adhesive will take pigment paste to form a thin film. In the first step of drying process, the dispersant and emulsifier within water and printing paste would be evaporated to form a gel layer, and this layer adheres to textile fiber by the form of loose. In the second step of fixing color processm, adhesive would cause cross-linking reaction on the textile fibers under the acidic conditions (pH <4).

If we want to use synthetic thickener, there is no need to additional put acidic medium in the pigment paste for textile printing.Because the neutral thickener will return to acidic conditions during fixation.

Currently, during the textile printing with water based pigment paste, the adhesives we used are mainly following three types:
 1. Acrylic adhesive;
 2. Butadiene-based adhesive;
 3. Nitrile adhesive;

Acrylic adhesive:
The acrylic adhesive is mainly composed by acrylic ester and an ethylene copolymer. These adhesives can ensure the good color fastness performance of pigment paste for textile printing. It is suitable hand feeling, but there is some limitation of  color fastness in drying washing.
Most of adhesives in the market is in this category, has been used for over 30 years. In the minds of textile printing workers, acrylic adhesive is still better in fastness and fiber hand feeling.


Butadiene-based adhesive:
This kind of adhesive can provide more soft hand feeling when using it with water based pigment paste for textile printing. But the printed fabrics become tacky in some of cases; although the overall color fastness is very good, however, durability is limited, the color is yellowing after a certain period time. Because of this negative impact on textile printing, it is rarely used in practice.

Nitrile adhesive:
This kind of adhesive can provide soft feeling on textiles after pigment paste printing, it is a product which is combined with acrylonitrile products, has good fastness in wet rubbing, washing, dry washing and etc.
Nitrile adhesive can not only used for cotton fabric fibers, but also used for silk fiber, synthetic fibers and blended fabrics, such as pure nylon fibers, pure polyester fibers and  fabric fibers blended with cotton or viscose. And accrylic adhesive is difficult used for these fibers pigment paste printing.

Nitrile adhesive also has some other advantages, the textile that is printed and worked by water based pigment paste and nitrile adhesive has suitable water absorption, this performance is very important to the chemical finishing, such as  waterproof, anti-fouling, flame retardant and so on.
When we need to increase the adding amount of nitrile-based adhesive to improve the color fastness, it will not affect the textile hand feeling likes acrylic adhesive, it also doesn't affect fabric's nap effect( Such as corduroy, jeanette and towel fabrics, etc.), to maintain the natural effect of the fabric itself.