In daily life, we can come into contact with all kinds of paper bags, such as shopping bags, bread bags, jewelry bags, etc. different paper bags may also have different materials and printing processes to highlight the design and texture, so as to improve the brand grade. So how do paper bags process finished products from raw materials? This article will introduce you to the production and printing process of paper products.
The production of paper bags is mainly divided into the following links:
① Material Selection
Paper bag is the extension of enterprise abstraction and commodity advertising strategy, so the selected materials, decoration technology and expression methods are closely related to the use and effectiveness of paper bag. Kraft paper has good toughness, high strength and rough appearance. Cardboard has good stiffness but poor toughness. It is generally required to cover the surface of paper bags. Coated paper has certain toughness and rich printing color, but its stiffness is worse than that of cardboard. Emphasize durability and choose kraft paper. When they are exquisite in color and stiffness, they mostly use cardboard, and demand rich and gorgeous pattern effects. People often prefer coated paper. In order to improve the taste and level of portable paper bags, designers use their brains on the post press appearance decoration technology. The sensitive application of bronzing, UV, polishing, colorful, concave convex and flocking also makes the color of paper bag bright, the sense of plane strengthened and the expressive force richer and richer. Of course, no matter what finishing process is adopted, designers should consider the economic application of paper materials and the sensibility of process design.
② Printing
Complex colors are often included in the design of paper bags. It is recommended to select high-quality printing machines for printing. LangHai has Heidelberg printing press imported from Germany, which can maintain high color accuracy and position accuracy in the process of multi-color printing.
③ Film Coating
Lamination refers to the post press finishing process of integrating paper and plastic by covering a layer of 0.012 ~ 0.020 mm thick transparent plastic film on the surface of the print. It is generally divided into two processes: pre coating and immediate coating. The coating material can be divided into high gloss film and matte film. With the application of environmentally friendly aqueous solvents, the environmental protection of film coating process has made further progress. Non cowhide paper bags are mostly covered with membrane technology, mainly because film mulching can increase the color concentration, enhance the waterproof, anti-aging, tear resistance and penetration resistance of the products, thus ensuring the strength and durability of the paper bags. The use of Matt film can give the product soft, high-grade, comfortable and other characteristics.
④ Surface Processing
Bronzing, UV and polishing are commonly used surface processing technologies for portable paper bags. It greatly meets people’s pursuit of exquisite and high-grade paper bags. In the process of consumption, we must also control the key points in these process links.
Compared with printing gold, the bronzing process has intense metal feeling, good divergence, bright color and richer plane feeling. The perfect bronzing effect depends on the inorganic coordination of bronzing temperature, pressure and speed. During bronzing operation, attention should be paid to the following factors affecting the hot stamping effect: 1 Appearance flatness of hot stamping goods; 2. Post printing treatment process for the appearance of hot stamping goods (film coating, oil coating, etc.); 3. Hot stamping suitability of anodized aluminum used; 4. Form of hot stamping plate and hot stamping machine, etc. Hot stamping is a complex technology. Only by fully considering the influence of the above factors in the hot stamping process can we achieve a satisfactory hot stamping effect.
The surface glazing process mainly refers to UV glazing and ordinary glazing. The polishing process can maintain a good gloss effect and improve the appearance wear resistance of the product. In particular, the application of UV polishing and some UV polishing in the paper bag processing process can make the printing layer of the paper bag thick and dense, rich and nourishing luster, prominent printing theme and strong appreciation.
⑤ Die Cutting
Die cutting process is the combination of die-cutting knife and indentation knife on the same template, and the application of die-cutting machine to stop die-cutting and indentation processing of printed products, also known as “rolling mark”. It is an important process in the process of paper bag consumption. The quality of die cutting indirectly affects the forming quality of paper bag and the efficiency of manual pasting.
Pay attention to the die-cutting process of portable paper bag: 1 Select the correct template. As a few paper bags have similar shapes and some sizes have little change, the first piece must be manufactured and rechecked against the engineering drawing during operation to avoid using the wrong template. 2. Control the task pressure. It is required that there shall be no burr on the die cutting edge, and the dark line shall be clear and easy to fold, but the line explosion shall be prevented. Some paper bags can’t see results in the dark line during die-cutting, but they will break when folding and pasting by hand. Therefore, in the process of die-cutting, try folding from time to time and check the process. 3. Considering the characteristics of the paper, the paper is easier to fold along the thread direction of the paper, and the molding pressure can be smaller. While perpendicular to the thread direction of the paper, the paper is more difficult to fold, and the molding pressure can be added to the part. 4. The toughness of cardboard is poor. If there is no surface coating, pay special attention to the die-cutting effect.
⑥ Pasting
Paste technology is the most special link in the manufacture of portable paper bags. In addition to some manual and semi-automatic processes, the use of paper bags is a secondary process. The demand for exquisite portable paper bags in developed countries is particularly huge. Because it cannot be completed through the automatic consumption line, it also provides business opportunities for the export of paper bag goods of many printing and packaging enterprises in China.
For the pasting of portable paper bags, the first piece process planning should be done first. 1. Select appropriate adhesive according to the paper bag data. Due to the lack of process experience, many paper bag factories often form paper bag false adhesive due to the improper selection of adhesive. The export paper bag needs to comply with the low temperature of 50 ~ 60 ℃ in the container and the high temperature test of minus 20 ~ 30 ℃ in the application place. At the same time, it is also necessary to consider the aging factors of the adhesive. 2. There are many kinds of paper bag commodities, such as the structure, handle information and combination methods of paper bags. We should discuss the use of appropriate manual techniques according to the detailed situation. Some need to punch the handle device hole before pasting, and some need to use hot melt adhesive to fix the portable device in the process of pasting, etc. The planning of these manual pasting processes needs to be completed before mass consumption. Once the process is confirmed, we should also strengthen the detail control in the manual pasting process to avoid glue overflow purification and prevent the appearance scratch of paper bags during consumption. Of course, for the first piece manufacturing of paper bag paste batch before production, you can refer to the process planning during proofing and stop the process re evaluation.
The hand-made hand-held paper bags have never been formed. Some hand-held paper bags also have the first process – punching, threading and other operations, so as to complete the final forming and packaging of hand-held paper bags.
After the above analysis and discussion of the process flow of portable paper bag, we know that the exquisite and fashionable portable paper bag is finally completed by a series of complex process. The negligence of any process link can lead to the occurrence of consumption quality accidents. The preciseness of technology is a necessary condition to ensure the high quality of goods. In the whole process, we should strengthen the evaluation management of the process and the implementation of the first article confirmation sequence before mass production of each process, and strictly track and control the consumption process. Any perfect process must rely on the strict implementation of the process operation sequence to ensure that the manufacturing of portable paper bags is no exception.
Post time: Mar-10-2022