1. The reasons for the occurrence of snowflakes on the goods are as follows:
(1) The print is sprayed with too much powder: the print is sprayed with too much powder, can not be completely dissolved by the adhesive, and a large area of snow spots will appear on the coated product. In this case, it is probably appropriate to increase the amount of glue, or sweep the powder on the print before laminating.
(2) The amount of glue is too small: the amount of glue is too small, and the entire appearance of the printed product will show snowflake points. The treatment method is to properly increase the amount of glue.
(3) The pressure of the pressure roller is inappropriate: the pressure of the pressure roller is too large, and the adhesive at the edge of the print is extruded, resulting in a snowflake point on the edge of the print; And if it is not compacted, it will also show snowflake spots. The treatment method is to correctly adjust the pressure of the pressure roller.
(4) There is dry rubber on the rubber roller: When there is dry rubber on the rubber roller, the amount of glue on the ground is small, which will make the coated goods show snowflake points here. The treatment method is to wipe clean the rubber roller.
(5) There is a rubber ring on the pressure roller: the adhesive extruded from the edge of the printing product or the adhesive extruded from the film hole is stuck to the pressure roller, and the boring rubber ring will be formed for a long time. When the back print is recoated, it will show tiny snowflake spots here. The treatment method is to wipe the pressure roller in time.
(6) There are impurities in the adhesive: if there is too much dust in the surrounding environment, or there are dry rubber and cut film fragments in the adhesive, there will be snow spots on the coated product. So. Special attention should be paid to environmental health; If the adhesive is not used up, it should be poured back into the glue bucket and sealed well, or filtered before gluing.
2. The product has bubbles
(1) The printing ink layer is not dry: first hot press again and then glue, but also delay the coating date, so that it is dry and complete.
(2) The printing ink layer is too thick: the amount of adhesive coating can be properly added, and the pressure and composite temperature can be increased.
(3) The surface temperature of the composite roll is too high: adopt air cooling, closed heating wire and other heat dissipation methods to quickly reduce the temperature of the composite roll
(4) The dry temperature of the film is too high: the dry temperature is too high, which will cause the adhesive surface to crust and blister, and the dry temperature should be properly reduced.
(5) Film reason: Because the film has wrinkles or lax appearance, the film is not uniform or curled edge caused by foaming problems, can be adjusted by adjusting the tension size, or replace qualified film to deal with.
(6) Adhesive concentration reason: the adhesive concentration is high, the viscosity is large or the coating is uneven, the amount is small, is also one of the reasons, then the diluent should be used to reduce the adhesive concentration, or the appropriate improvement of the coating amount and uniformity.
(7) The pressure of the pressure roller is too small: the entire appearance of the printed product has bubbles because the pressure of the pressure roller is too small, and the pressure of the pressure roller can be appropriately increased.
(8) Top paper: There are bubbles at the overlap of the two sheets of paper because the two sheets of paper are together before and after the laminating machine. This appearance is mainly manifested in the thick paper coating. If the print has a large mouth, the handwheel of the CVT can be adjusted counterclockwise to make the two pieces of paper have a certain amount of overlap; When the printing is in the mouth, the two sheets of paper can be properly spaced out, but it should be noted that the spacing should not be too large. Not true. After the product is cut, the tail film will appear.
(9) Print flapper: the storage of printed products is usually countless sheets stacked together, which forms the moisture absorption of the entire area of the paper is not very balanced, and the moisture absorption of the marginal area is more severe, which is the cause of the flapper. Flanged prints will flatten under the pressure applied by the film, but will return to their original state when removed from the pressure roll. And that's when you get a bubble. The method of treatment is: moistening or spreading to dry the print that presents the ruffled edge.
3. Coated goods show wrinkles
The main reason for the formation of coated goods showing wrinkles is that the film transfer roller is unbalanced, the film two ends of the tightness is inconsistent or wavy edge, the rubber layer is too thick, or the electric roller and the rubber roller at both ends of the uneven, inconsistent pressure, linear speed, In this way, we can adjust the transfer roller to the balance, adjust the film, adjust the amount of glue and improve the temperature of the drying channel, adjust the orientation and technical parameters of the electric heating roller and the rubber roller.
4. The bond at the edge is not solid
This appearance is mainly in the thick paper film. Thick paper will have a certain bending deformation when it is rolled up, and the smaller the diameter of the winding, the more significant. Just out of the pressure roll is not dry coated goods often will be bent at the edge of the paper top open, forming a bond here is not solid. In order to improve the rate of coated products, the width of the edge should be reduced as much as possible at this time to ensure that the width of the bonding is not solid in the range of die cutting mouth.
5. The main reasons for the formation of the problem are:
(1) The printed product is too thin: try to prevent the film processing of the thin paper.
(2) Tension imbalance: Adjust the tension of the film to reach balance
(3) Compound pressure is too large: properly reduce the compound pressure
(4) The temperature is too high: the composite temperature is decreased.
(5) The film tension is too large: the film tension is too large will cause the film to stretch and deform, and after the product is cut and removed from the external force, the film will return to its original state, causing the product to bend to the film side. The method of treatment is to adjust the depth of the screw and reduce the braking force.
(6) The winding force is too large: the winding force is too large, which will cause the film and the print to deform together, but the deformation is not the same. After the withdrawal of the external force, the product will bend to the side of the paper, especially thin paper. The treatment method is to reduce the friction of the winding power wheel.
(7) Large environmental humidity: After the film covered goods with high moisture content are full of dry, the paper will be dehumidified and deformed, causing the product to bend to the side of the paper. The treatment method is to control the workshop humidity.
(8) Short boring moment: short boring moment. Coated goods can not be full of boring, will bend. The way to deal with it is to extend the dull moments.
6. The main reasons for the formation of the problem are:
(1) The adhesive is not selected properly, the amount of glue is not set properly, and the ratio of measurement is wrong: re-select the adhesive trademark and the amount of coating, and the exact ratio
(2) The appearance of the printed product is not good: if there is powder spraying, the ink layer is too thick, the ink is not dry or not completed, etc., the dry cloth can be used to gently wipe off the powder spraying, or add the amount of adhesive coating, increase the pressure, and choose the photothermal pressing once again, or use the adhesive with high solid content, or add the adhesive coating thickness, or add the drying temperature.
(3) The adhesive is absorbed by the ink and paper, and the coating amount is lack: you can think about setting the formula and the coating amount from scratch.
(4) The amount of glue is too little: the amount of glue is less, the solid content is less, and the bonding force must not be. The treatment method is to increase the amount of glue.
(5) The printing area of the printed product is large: because the ink is lubricated, the adhesive is difficult to wet. Disperse. It's soaked, so it doesn't bond well. The treatment method is to increase the solid content of the adhesive and the thickness of the adhesive layer. Improve the external temperature of the film.
(6) Glue transformation: Check the factory date and shelf life of the glue before use.
(7) The film exceeds the shelf life
7. Uneven coating
Uneven thickness of plastic film, too small compound pressure, film slack, some adhesive curing rolls in the rubber tank swelling or deformation will lead to uneven coating; After the onset of the problem, you should quickly find out the reason and adopt the corresponding method, is to adjust the traction, increase the compound pressure, or replace the film, roller or adhesive.
