Temperature is the primary factor for pre-coating film laminating, because the adhesive on the pre-coating film is hot-melt adhesive, temperature determines the melting state of the hot-melt adhesive, and determines the direction of hot-melt adhesive molecules to BOPP film, printed matter ink layer, paper, etc. The penetration capacity and diffusion capacity. Although the increase in the temperature of the film is helpful for the enhancement of the bonding strength, too high temperature will cause the film to shrink, the surface of the product will be shiny, blistering, and the product will wrinkle. According to practical experience, the film temperature should be controlled between 70 and 100°C.
The surface of the paper of the laminating machine is not smooth, and only under the appropriate pressure, the hot melt adhesive in the molten state can completely cover the surface of the printed matter, and the laminating product is bright, and the bonding effect from the laminating machine is good. The pressure is small, and the bonding is not strong; the pressure is higher, which helps to improve the bonding force between the film and the paper product. However, if the pressure is too high, it is easy to cause wrinkles in the product, and it is easy to damage and deform the surface of the rubber roller, reducing the service life of the rubber roller. As the pressure increases, the contact pressure between the rubber roller and the heating roller increases, which increases the load and wear of the shaft heads and bearings of the two rollers of the laminating machine, and at the same time increases the load on the transmission system. Too much pressure will affect the service life of the whole machine.

The working mechanism of the pre-coating film laminating machine is to bond the plastic film coated with the adhesive and the paper printed matter after heating and pressing to form a paper-plastic product. It is a common paper printed matter at present One of the finishing processes. The coated printed matter has an extra layer of thin and transparent plastic film on the surface, which makes the surface smoother and brighter, which not only improves the gloss and fastness of the printed matter, and prolongs the service life of the printed matter, but the plastic film is also waterproof, Anti-fouling, abrasion resistance, folding resistance, chemical corrosion resistance and other protective functions.
In the pre-coating film method, the film manufacturer directly purchases the pre-coating film laminating machine, and when the film is needed, the film and the paper printed matter are hot-pressed on the pre-coating film laminating machine to complete the filming process. The pre-coating film process began in the 1990s. The hot-melt adhesive or low-temperature resin was uniformly coated on the film substrate in a quantitative and uniform manner through special equipment, and the result was a pre-coating film.
The coating categories used in the pre-coating film laminating machine industry are as follows:
1 The colorful coated ceiling is made of color-coated metal plate, imported PVC high-gloss film, PET phantom color film, coated with special adhesive on the surface of the board, and the surface pattern is rich in color and does not fade. Abrasion resistance, impact resistance, waterproof, fireproof, clear and convenient, etc., are the fashion trends of today's decorative ceiling products
2PVC high-gloss film has rich flexibility, gloss and diversified colors, completely changing the single cool color of the metal ceiling surface
3PET Symphony Film is currently the world's leading new green environmental protection product. It has excellent durability (weather resistance, corrosion resistance, chemical resistance) and anti-fouling ability, non-toxic and pollution-free, and has many superior performances of UV protection. And the application of light method fully caters to people's longing for green, advocating environmental protection, and pursuing the concept of fashion.

The laminating process adopted by the automatic laminating machine refers to the whole process of laminating pictures and photos, including film selection, laminating making, and cutting.
1. Cover the picture with a protective film to improve the strength of the picture and the wear resistance of the surface.
2. Isolate the picture from the outside air to prevent deformation and cracking caused by corrosive gases in the atmosphere, moisture, dryness, fading and discoloration caused by rain washing and ultraviolet radiation, and to maintain the bright color of the picture for a long time. Extend the life of picture display.
3. Paste the picture on the display board or cloth surface to make a hanging advertising screen.
4. Press a special mask or sheet on the picture to form a picture with special artistic effects such as bright, matt, oil painting, virtual, and three-dimensional.
The main problems common to automatic laminating machines are:
Surface blistering, wrinkles, uneven bending, shedding and separation, difficult storage, etc., these quality problems have not been solved for many years, and the reasons for analysis are also various, such as:
1. The influence of different types of paper.
2. The influence of different ink colors.
3. Different effects of climate.
4. The influence of environment and conditions.
5. The enterprise lacks the influence of scientific management.
6. The influence of the quality of the operator of the automatic laminating machine.

Although the overall performance of the pre-coating film coating method is better than that of the instant coating film coating method, in view of the current status of the domestic automatic laminating machine, the vast majority of domestic enterprises are still generally using the instant coating film coating process. The water content changes with the relative humidity of the air. Prints that are sensitive to humidity will generate internal stress due to dimensional changes. For example, the longitudinal expansion and contraction rate of printed matter is 0.5%, and the longitudinal thermal shrinkage of BOPP film is 4%. If the printed matter absorbs too much water and stretches, internal stress will be caused between the heating and shrinkage of the film, which will cause the laminated product to curl, wrinkle, and stick. The main reasons for insecurity can be summarized as follows.
First, the pre-coating film coating technology started relatively late in China.
Second, the production of pre-coating film has high technical content, complicated process, and large equipment investment. General enterprises cannot afford to invest in pre-coating film production lines.
Third, due to the surplus of labor resources and low labor costs in my country, material costs account for a large proportion of the overall cost of the film coating process. The cost of pre-coating film is higher than that of coating film, which will inevitably affect its application.
On the one hand, in terms of strength, the UV coating process has little contribution to enhancing the strength of the printed matter, while the laminating process can increase the strength of the printed matter several times. On the other hand, with the advancement of technology, further processing such as hot stamping and frosting after coating will make the post-processing process of printed matter more complicated. In today’s era when intellectual property protection is emphasized and businesses emphasize product anti-counterfeiting. Coating has more advantages than UV coating.
The laminating speed of the automatic laminating machine determines the melting time of the adhesive on the pre-coated film on the heating roller and the contact time between the film and the paper. The laminating speed is slow, the heating time of the adhesive on the BOPP film is relatively long, the pressing time of the film and paper is long, the bonding effect is good, but the production efficiency is low. The laminating speed is fast, the heating time of the adhesive on the BOPP film on the heating roller is short, the contact time between the film and the paper is short, and the bonding effect is poor. The production speed of domestic pre-coating film laminating equipment is generally controlled between 5 and 30m/min.

With various materials, the laminating process completed by the small laminating machine is divided into several categories according to the temperature and use of the raw materials (consumables) used, and the following categories are introduced.
Cold laminating: The method of laminating the protective film on the surface of the picture by cold pressing at room temperature is called cold laminating. Among them are single-sided mounting and double-sided mounting. In the operation method, there are also manual peeling and self-removing film mounting. The cold lamination process has the characteristics of simple operation, good effect and low cost. At present, it is widely used in the post-production of advertising light boxes, engineering drawings and wedding photography.
Principle of use of small laminating machine:
(1) Use instant coating film as cover to protect paper. After laminating, the service life of the cover (or the surface of the printed product) can be prolonged, especially for students' textbooks, so the amount is increasing.
(2) The impression is not easy to be destroyed. After being coated with a coating film, it can increase the color effect and protect the color printing graphics and texts without causing them to be worn. This is conducive to publishing houses' art editors to make various art designs on the surface of the cover or printed matter according to their needs, which also promotes the increase in usage.
(3) The production of coating film is profitable. In the coating process, the production cost of the coating film is low, easy to use, and profitable, and the enterprise can profit.