[0050] A method for preparing wallpaper with three-dimensional texture effect, the steps are:
[0051] ⑴Combined design of relief embossing roller, rotary screen printing plate wheel and precision coating machine:
[0052] The circumference of the roller type relief plate is 635-656mm, the pattern is continuous engraving design, the depth of pattern engraving is 1-5mm, the printing cylinder specification is 641mm outer diameter and circumference, open-hole mesh 20-80 mesh, precision coating The cloth machine adopts knife coating or reverse roller coating, and the design width is greater than 500mm. It can be made into a pattern that can be printed with a tolerance of less than 0.3mm; it can also be designed with an abstract pattern that is not aligned, and the number of printing sets is 1-4 printing Bit
[0053] ⑵Slurry adjustment:
[0054] Choose PVC slurry with thixotropic properties or water-based tile cracking slurry, adjust the color according to the design requirements, and scrape;
[0055] ⑶ Installation of the scraper in the printing unit of the rotary screen printing coating machine:
[0056] ①Put the inner scraper plate of the rotary screen on the plate mounting rack, and place the inner scraper plate on the inner scraper plate mounting rack according to the process requirements, accurately adjust the size of the inner scraper plate and straighten it. Scraper plate, and then tighten the inner scraper plate pressing plate bolt;
[0057] ②Install the carved rotary screen wheel on the printing unit of the rotary screen printing machine, and then install the adjusted size of the inner scraper plate into the rotary screen wheel, and fix it in position and lock it in On the rotatable plate rack, adjust the position of the inner scraper and the pressure of the inner scraper; the position of the inner scraper is 40-80 mm, and the pressure of the inner scraper is 0.5-1.0kg/㎡;
[0058] ③Adjust the thickness of the coating gap of the precision coating machine between 0.05-2.0 mm according to the product design requirements.
[0059] ④The relief embossing roller is installed on the machine base and connected to the servo drive to accurately adjust the embossing gap.
[0060] ⑷Inject the bottom layer slurry for rotary screen printing:
[0061] ①Insert the automatic liquid level control gauge into the printing cylinder, and use a transfer pump to inject the adjusted color PVC slurry with thixotropic properties or the water-based tile cracking slurry into the cylinder printing unit; transfer and print according to the process requirements Flower-shaped pattern, and the wet material of the rotary screen printing pattern is sent into a drying oven to be heated to a semi-gel state. The heating temperature is adjusted with the change of the production line speed, generally between 100-200 degrees Celsius.
[0062] ②The tempering roll is cooled to below 50 degrees Celsius.
[0063] ⑸Inject the surface layer slurry for surface layer coating and printing:
[0064] ①Introduce the substrate with the printed bottom layer into the second section of the production line rotary screen printing unit or precision coating machine unit for surface layer coating and plate printing.
[0065] ②Do surface treatment of the wet paste after the surface layer is printed. The treatment method is to use a low-frequency heater to instantly condense the surface.
[0066] ⑹Wet relief embossing:
[0067] ①After adjusting the embossing gap according to the pattern design requirements, press down the relief embossing roller in parallel. The contact point between the relief embossing roller and the substrate is non-hard contact, and the longitudinal speed slip is not greater than ±2mm. The slurry is raised on the edge of the flower shape through the extrusion of mechanical slip, and the width of wet relief embossing is 300 mm to 2000 mm.
[0068] The product can also be used for secondary surface embossing. At this time, it needs to be equipped with an outer-span felt transfer roller and a washing roller. The roller diameter is 10-250 mm, and the effective working surface width is 300-2000 mm. The outer-span roller and the base The gap between the materials is 0.05-1.5 mm, and the rollers should be adjusted synchronously with the production line.
[0069] Irregular textures are produced after wet gap relief embossing. The minimum interval between the textures is 0.03 mm and the maximum interval is 30 mm. The texture is in a continuous and uninterrupted irregular curve distribution, during which the slip and relief caused by the embossing process of the relief gap on the pattern After the gap embossing, the wet material is subjected to external force to form a change in surface tension, which is manifested as a slope-shaped structure on the surface of the embossed coating, with convex edges and a straight line distribution of texture along the flower-shaped curve.
[0070] ② Dry and plasticize after embossing in the wet relief gap. The dry plasticization temperature matches the speed of the production line. The general temperature range is not less than 150 degrees Celsius, and the production line speed is 5-50 meters per minute.
[0071] ③Surface treatment and product cooling:
[0072] a. If the product that has been heated and plasticized (cured) needs to undergo surface leveling treatment, two methods are generally used:
[0073] There are two methods for surface flattening, a. After the surface is flattened, surface printing is performed, and the flattening uses cold roll hard gap embossing; b. The surface is flattened, and the surface is printed after reheating to eliminate the surface bumps. The flattening method is Hot rolling flexible gap embossing.
[0074] b After the product is cooled to below 30 degrees Celsius, it can produce wet relief embossed wallpaper products with diverse raised edge textures and variable structural levels.
[0075] It should be noted:
[0076] The process control of the rotary screen printing drying temperature during the product processing of the present invention and the process temperature control before and after the relief gap embossing determine the texture effect of the product. When the product thickness is constant, the temperature will increase with the line speed when the production line speed changes. When the temperature rises, the temperature will decrease on the contrary.
[0077] The slope effect of the embossed part produced by the product of the present invention after embossing is formed by the mechanical speed slip of the gap embossing process. Under the condition of constant thickness, the smaller the embossing gap, the less obvious the slope of the slip. , The higher the protrusion of the lace under the effect of slip; on the contrary, the larger the gap between the relief plate and the substrate, the smaller the slope effect and the smaller the height of the lace protrusion.
[0078] The PVC slurry with thixotropic properties used in the present invention can also be called thixotropic PVC plastisol. It is a special PVC slurry produced by Tianjin Changyanggu Plastic Technology Development Co., Ltd. It is used for various PVC printing and coating. Its product features are that the paste has a high paste viscosity, and it will not change in viscosity at high shear rate during high shear printing and coating. It is especially suitable for rotary screen coating. Fabric printing, and the printed product has the special effects of clear flower-shaped corners, regular printing dots and obvious edges.
[0079] The main raw material components of PVC slurry are: PVC paste resin, DOP or DINP plasticizer, barium-zinc heat stabilizer, coloring agent, and filler.
[0080] Process requirements for PVC slurry: thixotropic PVC slurry is a low-volatility oily slurry. Therefore, the printing process must be cured or plasticized at a high temperature above 130 degrees Celsius after printing. After curing or plasticizing Register printing can be done after film formation. The thixotropic PVC slurry must maintain the original viscosity during the production process. The customer cannot use ordinary viscosity reducers to reduce the viscosity during use. If the product production must reduce the viscosity of the paste, special materials should be used to reduce the viscosity under the guidance of the professional and technical personnel of the supplier. . The pigment used in the tinting of the thixotropic PVC slurry must be adjusted after the laboratory test is successful. Pay special attention to the dispersant in the pigment that may change the performance of the thixotropic PVC slurry. Although the thixotropic PVC paste can be printed with water-based ink after curing, it should be noted that the two materials cannot be blended when using it at the same time.
[0081] Safety of PVC slurry: The thixotropic PVC slurry formula does not contain harmful substances directly to humans, and will not cause harm to humans. The products comply with the EU ROHS environmental protection directive.
[0082] The water-based tile cracking slurry used in the present invention can also be called water-based cracking slurry. It is a special water-based slurry produced by Tianjin Changyanggu Plastic Technology Development Co., Ltd. It is mainly used in wallpaper, artificial leather, The surface printing and coating of floor leather and textiles. The product feature is that the surface of the substrate after printing and coating the water-based tile crack slurry will produce surface irregularity cracks at a certain process temperature. The cracks also have With the adjustment of the processing technology, the texture of the crack will change differently.
[0083] The main raw material components of the water-based tile crack slurry: acrylic emulsion, talc, titanium dioxide, and pure water.
[0084] Process requirements for water-based tile cracking paste: water-based tile cracking paste is a water-based paste, so in the printing process, the printing process must be cured at a high temperature of 130 degrees Celsius after printing, and then it can be cured into a film. Do register printing.
[0085] The water-based tile crack slurry must maintain the original viscosity during the production process, and the customer cannot reduce the viscosity during use. If the product production must reduce the paste viscosity, special materials should be used to reduce the viscosity under the guidance of the professional technicians of the supplier.
[0086] The pigment used in the color mixing of the water-based ceramic crack slurry must be successfully tested in the laboratory or be adjusted again. Pay special attention to the dispersant in the pigment that may change the performance of the water-based ceramic crack slurry.
[0087] Although the water-based tile crack slurry can be used for printing and matching with the oily PVC slurry after curing, it should be noted that the two materials cannot be blended when using it at the same time.
[0088] The safety of the water-based tile crack slurry: the formulation of the water-based tile crack slurry does not contain harmful substances that are directly harmful to humans and will not cause harm to the human body. It is an environmentally friendly product and the product complies with the EU ROHS environmental protection directive.
