Problems to be Noted in Using Cover Oil for Winter Production of Small Foil Paper

In winter, the cold temperature is relatively low, especially in northern China, temperatures are below ten degrees Celsius. During the production period, the following problems should be noted:

1. The cover oil should be stored in a warmer warehouse with a temperature of about 20 degrees. If the warehouse is not in good condition, it should be placed in the production workshop two days before use to allow it to return to the production room temperature. The reason is that the viscosity of the cover oil changes with the change of the temperature, and the temperature becomes lower and the viscosity increases. On the contrary, it becomes smaller. Since the viscosity cannot be stabilized in a range of values, the printability becomes poor at the time of printing, and the product quality will be inconsistent.

2. The temperature of the production workshop is controlled at about twenty degrees, which will maintain a stable temperature environment in the production workshop, and create a stable condition for production control so that the print oil printability is relatively stable, so as to produce products of consistent quality.

3. Printing oil is best used in flat-press printing. Flat-press printing produces better quality products. Drying and drying use flat-laid paper holders so that the cover is dry and the film thickness is uniform. , And bright, film thickness in the 20um or so, the lowest not less than 15um, or the factory is easy to use deformation, fracture and poor operation problems.

4. The products that have just been printed should not be immediately dried at a high temperature. They should be placed on a flat paper holder for a few minutes to allow the cover to flow flat and then put under high temperature. The drying temperature is set at 60-65 degrees Celsius. Better, the temperature is too high will produce false dry phenomenon, high temperature drying equipment should have good exhaust equipment, so that the solvent gas molecules released from the cover oil will be rapidly discharged when drying, otherwise the solvent gas molecules can not be quickly discharged to a certain extent Concentration, but will affect the drying effect. Therefore, the drying equipment must ensure good exhaust conditions. The drying time is generally better than twenty minutes. After drying the product at high temperature, after the drying box, do not pack it immediately, place it in a well-ventilated greenhouse, and dry it. After some time, proceed with packaging.

5. The printing plant that does not have the drying equipment condition must be well ventilated in a clean and dust-free room at 20 degrees Celsius or above.

6. Use automatic drying line (upright paper holder) drying equipment, pay attention to the use of the cover oil viscosity is not too low, the viscosity is too low will appear drape phenomenon, the upper end of the film thin direction film thickness. Use a good touch Degenerative cover oil is better, but the price should be higher.

7. Due to the different types of equipment used in various units, process methods, raw materials, and different production environments, it is not possible to generalize, but one principle is to ensure that the cover oil is heated and filmed after leveling, otherwise pinholes will occur, orange peel will be uneven, and high temperatures will occur. Can not be packaged immediately after drying, wait for cooling to see if it is completely dry, and then determine the packaging. How to determine whether the dryness can be judged using the following simple sensory method: (a) olfactory method; smell the membrane with the nose there is no Stronger solvent odor (b); Indentation method; Press with fingernail on the membrane surface to see if there is any indentation on the membrane surface. (c) Measure adhesion; press the membrane against the membrane surface. Together, and then separate them to observe if there is a sticky phenomenon. (d) Water immersion test; This method immerses the paper in the water after the film is detached from the paper according to the method of use of the factory, and the film is picked up and pulled. There is strength, it is good paste. After a comprehensive test can basically determine whether it is dry.

8. Do not wrinkle the wrapper or paper on which the paper is placed. Place the wrapper in the box. Do not place it horizontally. Store it in an upright position to avoid wrinkles.

9. Delivery and transportation should be marked with fear of pressure, not folding, stacking, moisture proof mark. In winter, the temperature of the external environment is too low, the film will become brittle, reminding the factory that the flower cutting work cannot be carried out immediately, and the paper will be placed on it. Warming the interior slowly to ease the freezing, and then cut the flowers, otherwise it is easy to break the internal structure of the small membrane, resulting in small internal structure of the membrane cracks can not be seen with the eye, when used by water soaked a stripping will break on their own.

10. During the process of printing the cover oil, the production records of each link and the batch number of raw materials must be properly prepared. Once problems arise, they can be easily analyzed and resolved. The above methods are for reference only. Each factory shall formulate process methods according to their specific conditions.

Source: Tianjin Tianquan Printing Material Industry Co., Ltd.