在包裝印刷行業，覆膜的效果不僅與覆膜的原材料和操作方法有關，更重要的是與被膠印刷品的墨層狀況有關。印刷品的墨層狀況主要由紙張的性質、油墨性能、墨層厚度、印刷圖文的圖形面積和整體密度等決定。下面
濟南彩色設計印刷廠家為您講解：
In the packaging and printing industry, the effect of film covering is not only related to the raw materials and operation methods of film covering, but also to the ink layer of the offset brush. The ink layer condition of printed matter is mainly determined by the paper property, ink performance, ink layer thickness, graphic area and overall density of printed images and texts. Next, Jinan Color Design and Printing Factory will explain to you:
1.印刷品的墨層厚度。
1. The ink layer thickness of the printed matter.
墨層厚的實地印刷品往往難以與塑料薄膜粘合，很快就會脫層起泡。這是因為較厚的油墨層改變了紙張的多孔表面特性，使紙張的纖維孔隙封閉，嚴重阻礙了粘合劑的滲透和擴散。粘合劑一定程度的滲透有利于涂膜的粘合。
Field prints with thick ink layer are often difficult to bond with plastic film, and will soon delaminate and blister. This is because the thicker ink layer changes the porous surface characteristics of the paper, closes the fiber pores of the paper, and seriously hinders the penetration and diffusion of the adhesive. A certain degree of penetration of the adhesive is conducive to the adhesion of the coating film.
油墨層的厚度也與印刷方法直接相關，不同的印刷方法油墨層的厚度也不同。比如平印產品的墨層厚度在L——2μm左右，凸版印刷的墨層厚度在2——5μm左右，凹印的墨層厚度可以達到10μm，從覆膜的角度來看，平印的印刷品比較理想，其墨層很薄。
The thickness of the ink layer is also directly related to the printing method, and the thickness of the ink layer varies with different printing methods. For example, the ink layer thickness of lithographic products is L-2 μ About m, the ink layer thickness of letterpress printing is 2-5 μ About m, the ink layer thickness of gravure printing can reach 10 μ m. From the perspective of film covering, lithographic printing is ideal, and its ink layer is very thin.
2.印刷油墨的種類。
2. Type of printing ink.
被覆膜的印刷品應采用快固型光亮膠印油墨，這種油墨的連結料由合成樹脂、干植物油、高沸煤油和少量樹膠組成。合成樹脂分子中含有極性基團，易與粘合劑分子中的極性基團擴散滲透，交聯形成物理和化學結合力，有利于覆膜；快速固色這種淺色膠印油墨還有一個好處就是印刷后結膜干燥快，對覆膜也非常有利。但使用時不宜加入過多催干劑，否則油墨層表面會結晶，反而影響覆膜效果。
The film-coated printed matter shall use quick-setting bright offset printing ink, which is composed of synthetic resin, dry vegetable oil, high-boiling kerosene and a small amount of gum. The synthetic resin molecules contain polar groups, which are easy to diffuse and penetrate with the polar groups in the adhesive molecules, and cross-link to form physical and chemical binding force, which is conducive to film covering; Another advantage of this light-color offset printing ink is that the conjunctiva dries quickly after printing, which is also very beneficial to film covering. However, it is not advisable to add too much drying agent when using, otherwise the surface of the ink layer will crystallize, which will affect the film covering effect.
3.油墨稀釋劑的使用。
3. Use of ink thinner.
油墨稀釋劑是一種能使油墨顏色變淺的物質。印刷前應仔細選擇自墨，盡量使用均勻細膩、無明顯顆粒的自墨作為稀釋劑。
Ink thinner is a substance that can make ink color lighter. Before printing, the self-ink should be carefully selected. Try to use the self-ink that is even, fine and free of obvious particles as the diluent.
4.添加粉末噴涂。
4. Add powder spraying.
為了適應多色高速印刷，膠印中常采用噴粉技術來解決臟背問題。噴霧粉大多由谷物淀粉和天然懸浮物組成。噴粉的防粘作用主要是在墨層表面形成不可逆的墊層，從而降低附著力。由于顆粒較粗，如果在印刷過程中噴粉過多，這些顆粒就會漂浮在印刷品表面。覆膜時，粘合劑不會處處與油墨層粘合，而是與這層噴粉粘合，從而造成假貼，嚴重影響覆膜質量。因此，如果印刷產品需要涂層，印刷時應盡量控制噴粉量。
In order to adapt to multi-color high-speed printing, powder spraying technology is often used in offset printing to solve the problem of dirty back. Spray powder is mostly composed of cereal starch and natural suspended solids. The anti-sticking effect of powder spraying is mainly to form an irreversible cushion on the surface of the ink layer, thus reducing the adhesion. Due to the coarse particles, if too much powder is sprayed during the printing process, these particles will float on the surface of the printed matter. When laminating, the adhesive will not bond with the ink layer everywhere, but with this layer of powder spraying, resulting in false pasting and seriously affecting the quality of laminating. Therefore, if the printed product needs coating, the amount of powder spraying should be controlled as much as possible during printing.
5.印刷品表面內層的干燥情況。
5. The drying of the inner layer of the printed matter surface.
印刷品的油墨層干燥不良對涂布膜的質量危害很大。除了油墨的種類、印刷過程中催干劑的用量和種類以及印刷和儲存間的環境溫濕度外，紙張本身的結構也很重要。如果銅版紙和膠版紙的結構不同，墨層的干燥條件也不同。
The poor drying of the ink layer of the printed matter is very harmful to the quality of the coating film. In addition to the type of ink, the amount and type of drying agent in the printing process, and the ambient temperature and humidity in the printing and storage room, the structure of the paper itself is also very important. If the structure of coated paper and offset paper is different, the drying conditions of the ink layer are also different.
無論是銅版紙還是膠版紙，在油墨沒有完全干燥的情況下，對銅版紙的質量都是不利的。油墨中含有的高沸點溶劑很容易使塑料薄膜膨脹伸長，塑料薄膜的膨脹伸長是涂布后產品起泡、分層的主要原因。
Whether it is coated paper or offset paper, if the ink is not completely dry, it is unfavorable to the quality of coated paper. The high boiling point solvent contained in the ink can easily make the plastic film expand and elongate. The expansion and elongation of the plastic film is the main reason for the blistering and delamination of the coated product.
In a word, these factors affect the formation conditions of adhesive mechanical adhesion, physical and chemical adhesion, and thus cause changes in the surface adhesion of printed matter. For more matters related to printing design, please visit our website http://www.zhouyingzi.cn Ask!
