Discussion on the Process Practice of Fleeting Foam Three-Dimensional Printing

With the improvement of living standards, people have made great changes in the concept of wearing clothing fabrics, not only pay attention to the style of clothing, but also stressed the texture of the fabric, feel, look and other combinations with the clothing style, but also for taking The requirements for comfort, beauty, and warmth and warmth are also raised. The emergence of fleece printing and foaming products adds to the unique and unique variety of textiles and satisfies people's consumer needs.

1 Fleece foaming three-dimensional printing principle

1.1 Fleeting and Foaming

Fleece foam three-dimensional printing belongs to the practice of printing a traditional flat new pattern on a flat fabric with a three-dimensional effect. The fleece print resembles a velveteen embroidered fabric and a three-dimensional foamed print pattern, which gives the fabric a jagged, bright and colorful appearance. Printing methods and equipment and processes are similar to those of general paint printing. However, in the heat treatment, the pattern rapidly rises and swells, resulting in a different three-dimensional shape.

1.2 Pulp printing paste composition

The composition of the printing paste for fluff printing is as follows.

Microcapsule preparation 40g～60g～

Adhesive/10g～15g

Adhesive/0g～5g

Urea 5g～10g

Thickener/suitable amount/100g

1.3 Foaming foam printing pattern and color design

Due to the thick texture of raised foam printing, pattern design should use a pattern with large blocks and strong contrasting colors to enhance the visual impact. The dragon pattern, phoenix pattern, gold pattern and other animal patterns in the folk embroidery can be used, together with the traditional embellishment, moiré pattern, curled pattern and other embellishments to form a rich and auspicious decorative effect. The design of the pattern uses imitation embroidery methods such as "picking flowers", "cross-stitch" and "flat embroidery". Numerous patterns of different shapes compose the layered texture of warp and weft parallel threads, vertical lines, and 45-degree diagonal lines of the warp and weft, making the pattern appear natural and casual. The color design of the pattern may have a tendency of color glaze, each pattern has a distinct hue, or a red tone, or a blue tone, or a green tone, so that the color of the pattern is clear, strong, and coordinated. Times, arranged appropriately.

2 foam paste additives selection and its effect on stability

Foam printing paste is composed of all-water adhesives, foaming agents, stabilizers, etc. It is a kind of relative that through the mechanical method, a certain proportion of air is evenly mixed in to form numerous fine uniform bubble micro-polymers. A stable dispersion system, which is printed on the fabric under the action of mechanical external forces. Due to the capillary action of the fibers and the wettability of the foam, the foam bursts and forms, the initial viscosity of the colorant is restored, and then the desired uniform printing effect is achieved.

2.1 Selection of additives

Foam printing foam size, strength, stability is mainly related to the foaming agent and stabilizer. Therefore, it must be selected so that it has a good compatibility, in order to have a relatively stable foam. Many surfactants can be used as blowing agents. Commonly used sodium dodecyl benzene sulfonate and sodium lauryl sulfate, stabilizers are hydroxyethyl cellulose, sodium alginate, dodecanol, stearic acid and so on. We believe that sodium lauryl sulfate is the foaming agent and stearic acid is the best stabilizer.

2.1.1 The amount of blowing agent

The main role of foaming agent is to reduce the surface tension of water. The amount of blowing agent will directly affect the foaming effect and the stability of the foam. If the amount is small, the surface tension of water cannot be sufficiently reduced, uneven foam will be produced, and the stability of the foam is also poor; if the amount is too much, too much foam will be formed, and the amount of liquid in the foam itself will be reduced and reduced. The wetting ability of the foam makes it impossible for the foam printed on the fabric to rupture and drain quickly after it has been drained, resulting in a poor surface finish of the fabric. Through a large number of tests, it is considered that the amount of blowing agent is suitable between 1% and 1.2%.

2.1.2 Stabilizer usage

Stabilizers are mainly used to increase the half-life of the foam and extend the life of the foam. The general dosage is controlled between 0.8% and 1%. Too little to achieve the purpose of stability, too much foam wet ability is not easy to break. 2.2 Effect of initial viscosity, pH and temperature on foam stability

2.2.1 Initial viscosity

Foam paste has a certain viscosity in order to ensure the normal working pressure of the foam and increase the thickness of the foam wall. According to the test results, it is considered that under certain conditions, the viscosity should be controlled at 35 Pa·s to 37 Pa·s, and the rotary viscometer should be used to measure the 3# rotor at 30 r/min. The viscosity is too low, the foaming effect is poor, and the foam is not uniform; the viscosity is too high and the printed fabric feels stiff.

2.2.2 pH

Foam-printing thickeners use PTF, the amount of which determines the initial viscosity of the coloring paste. Low pH, PTF can not be fully expanded, so that the rheology of the foam slurry is poor, the pH value is too high and the amount of PTF is increased, the fabric feels hard. The best puffed state of PTF is pH 9-10.

2.2.3 Temperature

The temperature has a great influence on the stability of the foam. Since the bubble is formed by the two phases of liquid and gas, the energy itself is not balanced, and the increase in temperature will exacerbate the thermal motion of the molecule, resulting in the rupture of the bubble. Therefore, a cooling tube is installed on the foam generator so that the produced foam always maintains the same temperature.

3 Conclusion

Foaming foam printing is a new process. The pattern printed with this process has a three-dimensional sense of flocking, embroidery and decals. The selection and amount of colorants, auxiliaries and the initial viscosity, pH value, temperature, pressure and other factors in the nap foam printing process have a certain impact on the quality of velvet foam printing products, and reasonable selection of additives , Strictly control the amount of foaming agent and stabilizer, can improve the quality of raised foam printing products.