The analysis of the actual operation points of the book plus cutting

Comparing with the prepress, printing and postpress processes in the printing process of books and products, cutting is a very inconsequential process that is easily forgotten and negligent. However, the stability of its work quality will directly affect the products of books and periodicals. The quality of the ring is good enough to attract everyone's attention.

The main contents of the cutting process include the opening of the dietary white materials, leaflets, brochure products, books and magazine covers, inserts (clips) pages, booklets of Lekoushu (special-shaped books), finished books, etc. Requires suitable specifications, smooth surface without burrs, no knife, no angulation, no damage, no wrinkle, no tens, no embossing, no pull flowers. The cutting equipment includes single-side knife cutting machines, three-side knife cutting machines, and fine and flat-packed linkage production lines, horse-riding-order linkage production lines, and other cutting equipment for cutting and lithographic paper.

In actual production, because the operator's cutting requirements and standards for different processed products cannot be fully understood, it is always easy to think that they can be cut out and can easily cause product quality instability. The author discusses some experiences and experiences in cutting the relevant issues that the product needs to pay attention to.

White material cutting

According to the printing requirements, the paper to be printed on the printing machine is commonly called white material.

1. Canadian transfer paper lithography
Lithographic paper is basically cut from rotary paper, and its size is 3mm larger than that of the flat-finished product. It improves the accuracy of finished lithographic paper products; all kinds of burrs, scraps, and paper scraps cannot flow into lithographic paper; The direction of the paper's silk stencil is influenced by the quality of printing and post-printing processing due to the formation of certain paper stencil directions due to differences in manufacturing processes. Therefore, it must be designed as straight-wire stencil printing and post-press processing.

2. Example of white lithographic printing
General requirements around the cutting is straight and 90 ° perpendicular vertical, smooth surface without edges, no flowers, no knives, no breakage, no wrinkle, not even Zhang, size specifications, the error ≤ 1mm, skew ≤ 1.5mm. If you do not cut according to the requirements, you will give troubles to the overprinting accuracy of the printing and the accuracy of the positive and negative fitting. Ultimately, it will affect the stability of the quality of the processed product after printing and the production efficiency. In serious cases, there will be a large product quality accident. .

3. To prevent moisture, dust, direct sunlight, flat placement and other measures
Single knife cutting machine cutting

Including the cutting of white materials and leaflets, such as leaflets, wall posters, advertisements, covers, inserts (clips) pages, cutting of text products, etc., and precautions in cutting.

1. Understand post-production requirements for cut products
Understand the thorough processing and use of the product, whether it is the process of directly cutting out the finished product or post-processing such as wrapping, folding, plastic head, and die cutting. In order to ensure smooth production and ensure the cutting quality of the product, necessary precautions should be taken.

1 Before construction according to single-bill, batch cutting, first draw cutting samples, confirm the location, specifications and construction orders require correct construction.

2 For high-precision products that still require post-processing, small batches (200 to 500 sheets) are required for cutting. For example, the trimming of the cover of the encapsulated product will affect the accuracy of the cutting because of the lack of uniformity in the cover of the product. This will result in inaccurate positioning when the device is wrapped around the cover. This will cause the top and bottom positions, left and right positions of the cover and the book to be included in the package. The core of the package error is too large, and can not reach the quality requirements, should control the cutting error in the 0.5 ~ 1mm below, in order to meet the book package after the spine word center, translation error ≤ 1mm quality requirements.

3 When cutting, it is necessary to keep the relevant working parts of the machine clean and prevent oil stains and rust from contaminating the printed products.

2. Prevents dirt, adhesion, and scratches caused by dry ink
After the printing department is finished, the product must be sent and the dryness of the ink must be checked carefully before cutting.

When one hand touches the surface of the printing port, especially in the area with large ink volume, it is not appropriate to immediately perform cutting when there is ink stickiness or ink blotting.

2 Use white paper to check the ink momentum conservation law of the large ink layer, and check if there is any phenomenon such as pulling ink or sticking, and determine whether the product can be cut.

3 Strengthen the inspection of the first batch (200 to 500 sheets) of cutting products; whether the knife is dirty, dirty, dirty, and cut edges. This phenomenon is caused by the fact that the knife edge is broken, not sharp, and the ink on the surface of the ink is not dried out and powder is missing, thus avoiding losses caused by blind mass production.

4 When cutting, it is necessary to place a thick paper on the paper pressure locator to prevent it from forming a gravure print on the surface of the printed matter when it works, which will affect the appearance. This is especially noticeable in the cutting of a single-sided knife cutting machine. Being neglected.

3. Need to cut special processing products
Hot stamping, silver, die-cutting, indentation, over UV, glazing, laminating and other products have very high precision of cutting, generally require cutting error ≤ 0.5mm. At the same time, some graphics are required to reserve paper edge, otherwise it will This will affect the accuracy of the product's nesting and embossing stamps. For the products requiring post-printing, it is required to reserve 2 to 3mm white borders on the layout, and place them on the edge of the prints, the tip and the pull tab. The use of paper edges facilitates lamination and product cutting, and special care must be taken when cutting similar products.

4. Cutting, coating and other products
1 The coating product must be inspected before the cutting of the glazed surface has been completely dry, not dry enough when the cutting will cause the product to stick, sticky, so the first hand touch inspection and the first small batch (200 ~ 500) test suitable After the batch construction.

2 film products must be shaken before cutting, because the surface of the printed film is covered with a film, sometimes with static electricity, it is difficult to reconcile, can be coated with a small amount of talcum powder or into the barn room 35 °C ~ 40 °C roast 1 ~ 2 hours also helps shake the Qi Qi.

5. Le mouth book cutting
In general, the production process of processing a booklet without a package line requires a cutting of the booklet kerf incision in advance, followed by encapsulation. The cutting size can be determined based on the thickness of a single book and the finished product specifications. For example, a large 16-sheet plastic book product is a 297mm*210mm book with a book thickness of 15mm or less, a general book width of 211mm (milling back 2mm, back glue thickness of 0.7 to 1mm), a book thickness of 15mm or less, and a book width 211.5 to 212mm (milled back 2mm, adhesive thickness between 0.7 ~ 1mm); book thickness of 15mm or more, book width 211.5 ~ 212mm (milling back 2.5 ~ 3mm, back glue 1.2 ~ 1.5mm). The purpose is to mill the back, pull the groove, plastic package, the finished product can reach the contract size range.

(to be continued)