laminating machine——SWFM-720A
What are the principal machine parameters of this machine?
SWFM720A+, similar to SWFM520A+, It's a sizeable hydraulic roll laminating machine with oil heating and slitting. But its max paper size is 685mm, more significant than 520A+, and the operating speed is 0-25m/min. Furthermore, the laminating temperature is 50-120℃. Besides, the total power is 4kW, and the dimensions(L×W×H) are 1.38×1.1×1.4m. lastly, the pressure is 3~8MPa.
What is the difference between cold lamination and hot lamination?
The lamination process can be divided into cold (cold pressing) lamination, hot (hot live) lamination, and liquid lamination according to cold and heat, pressure conditions, and materials. Hot lamination technology refers to the heating and activating of the pre-coated adhesive on the film, through which the film and the printed product are bonded. In contrast, cold lamination relies on the adhesive to connect the film and the printed product through pressure. Together.
Lamination, also known as "over-plastic," "laminating," "filming," etc., is the primary process of post-press processing. It means that the transparent plastic film is pasted to the surface of the printed matter by hot pressing to form a 10-20um movie, which can protect the printed matter and increase its gloss.
The pre-coated thermal lamination process coats the plastic film coated with adhesive on the surface of the printed matter after heating and pressure treatment so that the plastic film and the printed matter are bonded together. Water-based lamination is a cold lamination process, and its process complexity is between the coating film and pre-coated film.
What are the influencing factors of the quality of lamination?
For lamination, which has high requirements on temperature and humidity, the correct handling of lamination temperature, lamination pressure, and lamination speed ensures lamination quality. It brings an excellent operating interface to subsequent processes. The lamination environment (humidity/temperature), pre-coating film performance, printed paper, and published ink layer condition must also be closely related to the quality of the lamination.
If there is too much rain, moisture, and high humidity on the paper, the printed product will be covered without drying. After the product is gradually dried after filming, the water vapor in the report will evaporate, and a flower will form between the surface of the paper print and the plastic film. Spots or bubbles, so before the lamination and printing process, dry the paper prints and adjust the temperature and humidity of the workshop. Suppose the surface of the printed matter is white after lamination. In that case, it may also be because the temperature and humidity of the lamination site environment are too high, which causes the outer layer of the paper printed matter after lamination to dry. However, the inner layer is still not dry, so the surface of the article published issue after lamination is white.
In addition, the lamination of paper prints is also prone to the phenomenon of tight paper edges or the formation of wavy ruffles. The curling and wrinkling of the lamination products during processing may also be caused by the high humidity of the paper prints or the high ambient temperature and humidity of the production site. Therefore, the temperature and humidity changes in the workshop must be strictly controlled before laminating, and the deformed printed paper should be knocked flat before laminating.
How does pressure affect laminating machine when it's working?
Pressure: Appropriate pressure should be used while controlling the lamination temperature correctly because the surface of the paper itself is not very smooth; only under pressure will the hot melt adhesive in the viscous flow state drive away the air on the surface of the printed matter. Wet the surface of the paper and print well. Generate colloidal molecules to the ink layer of paper prints, the diffusion, and dislocation between paper molecules, achieve good bonding, form a complete coverage of the entire surface of the printed matter, and make the printed matter bright, fog-free, adhesive layer leveling, and crease-free, The bonding effect is good. In the case of no wrinkling, the pressure should be appropriately increased to make the thermoplastic curing function of the hot melt adhesive entirely performed. Physical peeling, impact force, and other influences have strong resistance (such as indentation, bronzing, hot melt adhesive skin, etc.) to achieve the perfect unity of composite prints' internal structure and surface state.
What problems will occur if the temperature control of the pre-coated film laminating machine is inappropriate?
When laminating different substrates, the temperature of the electrically heated steel drum must be adjusted according to the product to be covered. If the laminated substrate is gold cardboard, the temperature of the laminated steel drum should be controlled at 70°C to 80°C: if it is to coat 250g/m2 or 300g/m2 of gray and white board paper, the temperature should be adjusted to 80°C to 80°C. 90°C. The whiteboard paper absorbs much more moisture during the placement process than the gold cardboard. Especially on rainy days and winter, if the temperature adjustment is not appropriate, the lamination products will not shine. When laminating, it is sometimes found that there are clear water droplets or steam on the silicon roller, which is caused by the paper absorbing a lot of water. The lamination temperature of such products must be raised a little more. For the first product, the temperature of the drying tunnel can be controlled at 50℃～60℃. Use the glued film to stick it with your fingers at the outlet of the drying tunnel, no traces are visible, and a slight stickiness is enough. If the temperature of the film is too high, it will blister. Therefore, the temperature of the heating steel drum must be controlled according to the product's characteristics when laminating.
How do we control the quality of lamination?
The lamination process is often used in the production of trademarks and packaging. However, in actual production, due to improper operation by the operator or other reasons, quality problems such as wrinkling, blistering, and curling are often caused after the product is coated.
In production, the operator must operate correctly, grasp each link well, and make the product meet the quality requirements. Let's talk about the quality control of laminated products.
Control of products to be constructed
1. The product to be constructed must be straight. Unstraight paper with "ruffled edges" and "tight edges" should be treated. The "ruffled" form can be baked, and the "tight edge" paper can be hung to dry.
2. Be sure to wait for the blot to dry before applying the film; otherwise, it will cause blistering or hair pulling.
3. When printing, try to spray as little powder as possible. Otherwise, it will cause emptying and blistering of the pile of powder. Before laminating, the powder should be removed, the ones with a large number of prints can be hung to dry to remove the powder, and those with a small number of images can be wiped manually.
4. Attention should also be paid to the direction of paper strands when laminating incredibly thick paper to reduce the phenomenon of paper curling due to rolling and stretching.
Control of the operating process
1. The thickness of the glue should be appropriate. If it is too thick, it will cause curling and affect the gloss; if it is too thin, the viscosity will not be enough, and it will even cause foaming. It should be adjusted according to the product. Generally, the coated paper is used to be thinner, and the offset paper is managed correctly to be thicker.
2. The pressure should be adjusted according to the product condition. Generally, the force of coated paper should be smaller than that of offset paper, and that of thin paper is smaller than that of thick paper.
3. The temperature is generally controlled at 40 to 60 °C. Too high a temperature will deform the paper and film, causing the product to curl, but it should not be too low. Otherwise, it will cause low viscosity. The temperature of coated paper should be slightly lower than that of uncoated paper.
4. The film tension should be appropriate. Generally, it is advisable to maintain regular work without lag. Too tight will cause the product to curl; too loose will cause wrinkling.
Temperature and Humidity Control
1. To ensure product quality, the temperature of the laminating workshop should generally be adapted to the printing workshop and should not be too high or too low.
2. The humidity is generally slightly lower than that of the printing workshop. Too much moisture can cause the product to deform or even wrinkle, and it can even cause curling after the product is processed. If the humidity is too low, static electricity will be generated during the lamination process of the development, which will affect the subsequent process.
Control of raw materials
According to the product's nature, the paper's thickness, and the quality requirements, the raw materials are correctly selected. Generally, if the article is thin, the film set should also be more delicate to avoid curling. Products with high requirements should choose a film with better gloss. The glue should be transparent and free of precipitation. The use of pre-coating films is advocated to reduce damage to human health.
What is the future development of laminating machines?
The development of all walks of life is inseparable from the social environment, and changes in the atmosphere have also prompted changes in the industry. Such as the promotion of Industry 4.0 for the post-press industry. Is Industry 4.0 a little early? The answer is fraught with uncertainty.
As a major manufacturing country whose demographic dividend is disappearing, China does not want to miss the new historical opportunity of Industry 4.0. During Premier Li Keqiang's visit to Europe, he and Germany signed the "China-Germany Cooperation Action Outline," which talked about Industry 4.0. "Premier Li Keqiang mentioned Industry 4.0 cooperation at this time, which means that my country should promote the integration of the two in the strategy of simultaneous development of industrialization and informatization." said Wu Hequan, former vice president and academician of the Chinese Academy of Engineering, "Industry 4.0 It is beneficial to China and has important value in promoting economic and social development."
For the vast majority of packaging and printing enterprises at present, enterprises can implement the primary transformation of "Industry 4.0". For example, an industrial parameter monitoring system is added to the equipment, and the task parameters (such as completion time, delivery time, output requirements, etc.), drawings, process descriptions, etc. in the management system are synchronized to the work interface only from the perspective of support. System status and process data are synchronized to the work interface to provide adequate job support. Such as product count, pressure, temperature, mold, voltage, etc., and give threshold warnings. After the initial stage of Industry 4.0, the higher goal of post-press equipment companies should be to systematically introduce intelligent packaging and printing equipment, which can implement production through the instructions of the information system. In addition, post-press equipment companies need to use the wireless Internet and the Internet of Things to realize the docking of intelligent production lines with suppliers and customers.
With the rapid development of mobile Internet technology and Internet of Things technology, the pace of human beings entering the "Industry 4.0" era is accelerating. China's post-press equipment enterprises must face up to this development trend and actively join in the integration of informatization and industrialization. For many packaging companies, this is undoubtedly a life-and-death challenge and a once-in-a-lifetime opportunity for transformation.
