Die indentation inaccurate specification analysis

Die-cut indentation is a production process matched with packaging, decorating and printing. It is widely used in the indentation and die-cutting processing of books, covers, trademarks, labels, cartons, cartons and other products. Through die-cutting and indentation processing, the printed product can achieve beautiful and applicable process requirements. Therefore, the effect of die cutting and indentation will directly affect the quality of the entire product and the market image. However, due to the influence of various adverse factors in production, the phenomenon of inaccurate die-cut indentation often occurs. There are roughly eight aspects as follows.

1 The thickness of the semi-finished product is not allowed to change due to the change in thickness.

After printing the semi-finished products, the change in thickness will affect the position of the finished layout after die-cutting and indentation. In particular, after the corrugated cardboard is inserted, due to the increase in its thickness, the position of the layout will be biased after die-cutting and indentation molding. Therefore, the correct position of the printing plate should be taken into consideration when printing the imposition after the product has been re-folded after adding the thickness.

2 The upper and lower paper magazines are not allowed to cause positioning error of semi-finished products

If the two layers of cardboard on the printing surface and the non-printing surface are not accurately affixed, the non-printing surface of the paper will protrude beyond the edge of the printing surface, which will inevitably result in the positioning error of semi-finished products. Daily production shows that no matter whether it is hand-cutting or automatic mechanical sticking, it will inevitably cause inaccurate phenomena. In order to prevent the non-printing surface of the post-printing paper from appearing on the edge of the paper, it is generally necessary to print it. According to the characteristics of the product, the side trim and front trim of the semi-finished product will be added with trimming margins ranging from 3 to 6 mm. When this is applied, the non-printing side of the paper edge shall be shrunk by a suitable amount in millimeters. Sticking can effectively prevent the occurrence of convex appearance on the non-printing side of the paper edge and ensure the accuracy of die-cutting.

3 The cardboard is obviously curled and the semifinished product is not positioned correctly

When the semi-finished product is curled or curled, especially after the corrugated cardboard half product after the stencil is placed on the platen, the paper surface and the die-cut plate are not in uniform contact, so that the warped paper surface and the layout are first The rubber strips or sponges are in contact with each other, so that the semi-finished printed sheets on the embossing plate are liable to slip, resulting in inaccurate die cutting. Therefore, maintaining a good flatness of the cardboard is an important part of improving the precision of semi-finished products. The key to controlling the flatness of corrugated board is to control the production process of the single-sided machine. We must choose corrugated paper and cardboard with similar moisture content, and control the speed and temperature of the single-sided machine to prevent The corrugated board shows a significant curl and affects the die-cutting accuracy of the product.

4 The paper surface stretching variation causes the layout specification to be inaccurate

For paper semi-finished products, if the stability of the paper is poor, the moisture content will obviously fluctuate in the printing process, especially after the product has been processed by calendering, laminating, or gluing, etc., after the inch: heat or moisture is absorbed. , The semi-finished product will undergo a change in telescoping, so that when the die-cutting indentation occurs, the position of the layout of the printed product will be deviated. In this regard, the solution is: try not to use freshly produced paper, but should put the newly produced paper for several months, make it relatively balanced with the printing conditions and then put it into use, so that its deformation coefficient is smaller. For products with higher precision, the coefficient of deformation of processes such as calendering, laminating, and gluing shall be fully considered, and the position of the layout shall be appropriately adjusted at the time of print imposition. In addition, it is necessary to control the temperature and humidity of paper warehouses, glazing, calendering, laminating, laminating, and die-cutting workshops, and the temperature and humidity of each production process. There must be no significant gap between the levels to ensure the position of die-cutting indentations. And specifications are accurate.

5 Misalignment of the paper grain direction causes the location of die-cutting indentation to be inaccurate

One direction on the vertical and horizontal planes is generally composed of multiple small layouts. If the paper that is most prone to stretching changes is laid horizontally to print the layout in the direction of multiple impositions, it is likely to result in inaccurate die cutting. Therefore, the layout has always been a multi-version structure, it should use the vertical silk paper to print, in order to better ensure the accuracy of die-cutting.

6 The position and specification of the layout are not allowed due to loose or deformed die-cutting indentation plate

Because the die-cutting indentation pressure is relatively large, if the layout size is too large and the version of the plate is not used, the fixing of the plate is not very firm. Thus, the die plate is easily moved along the lateral position of the platen during the production process. In addition, under the pressure of the die-cutting plate, the plate core may become solid, and the steel blade is also prone to bending and other undesirable conditions. These will also change the specifications of the die-cutting plate and affect the die-cutting accuracy of the product. Therefore, the production process should pay attention to careful observation and inspection, find problems and take timely measures to correct.

7 Rubber strip or sponge is too thick to cause die cutting

The role of the rubber strip and the sponge is to fully utilize the elasticity, and the die-cut semi-finished product and the scrap thereof are quickly separated and detached from the die-cut plate to achieve continuous and normal production. In general, the rubber strip is 3~5mm higher than the knife edge, and the sponge piece is better than the knife edge, and should be mastered according to the characteristics of the product reasonably. Only in this way can the better effect be achieved. During production, care must be taken to ensure that the flatness of the semi-finished product is not good, and if the rubber strip or sponge is too thick, the rubber strip and the sponge may be rubbed to the warped paper surface first when the pressure is applied. quasi.

8 Inadequate positioning of semi-finished products caused by poor machinery

If some parts of the die-cutting machine are worn out and loosened, the semi-finished products are likely to be misaligned. In this regard, the machine should be observed and inspected carefully, and appropriate measures should be taken to deal with the existing unfavorable conditions to ensure that the product is die-cut accurately.

In summary, the reasons for the inaccurate specifications of die-cutting and indentation of products are many, and the existence of one or more undesirable factors can cause the failure of die-cutting and indentation to occur and affect the quality of the product. Therefore, in the daily die-cutting production process, only those who are good at conscientiously summarizing the production experience and effectively shutting down the good operation technology and process technology and producing it scientifically and reasonably can effectively prevent such or such failures from occurring and ensure the die-cutting quality of the products. .