紙張對(duì)油墨的吸收是否影響印刷?

文章作者：華政印務(wù) 發(fā)布時(shí)間：2021-08-10 66次

紙張吸墨性不僅與紙張的疏松程度及毛細(xì)孔狀態(tài)有關(guān)，還跟紙張纖維的表面性質(zhì)，填料、顏料、膠料的含量，油墨的組成和特性，印刷方式，印刷壓力等因素有關(guān)。在實(shí)際印刷中，紙張對(duì)油墨的吸收可分為兩個(gè)階段。階段是印刷機(jī)壓印瞬間，依靠印刷壓力的作用把轉(zhuǎn)移到紙張表面的部分油墨壓入紙張較大的孔隙，即油墨整體(包括油墨中的顏料)進(jìn)入紙張孔隙，這個(gè)過(guò)程一般稱(chēng)為加壓滲透階段。

The ink absorption of paper is not only related to the degree of looseness and pore state of paper, but also related to the surface properties of paper fiber, the content of filler, pigment and rubber, the composition and characteristics of ink, printing mode, printing pressure and other factors. In actual printing, the absorption of ink by paper can be divided into two stages. The first stage is the moment when the printing press presses. Depending on the printing pressure, part of the ink transferred to the surface of the paper is pressed into the larger pores of the paper, that is, the whole ink (including the pigment in the ink) enters the pores of the paper. This process is generally called the pressure infiltration stage.

在這一階段，紙張對(duì)油墨的吸收主要取決于印刷壓力的大小、紙張的結(jié)構(gòu)和油墨黏度等因素。如印刷壓力較大或紙張的結(jié)構(gòu)疏松，紙張對(duì)油墨的吸收能力也會(huì)較強(qiáng)。一般來(lái)說(shuō)，印刷結(jié)構(gòu)疏松的紙張，如新聞紙、凸版紙等非涂料紙，印刷壓力應(yīng)小一些，油墨黏度也應(yīng)低一些。而印刷結(jié)構(gòu)緊密的紙張，如涂料紙，印刷壓力可適當(dāng)大一些，油墨黏度也可稍高一些。第二階段是從紙張離開(kāi)壓印區(qū)，直到油墨完全干燥為止，這一階段主要是依靠紙張的毛細(xì)管作用吸收油墨，稱(chēng)為自由滲透階段。

At this stage, the absorption of ink by paper mainly depends on factors such as printing pressure, paper structure and ink viscosity. If the printing pressure is large or the structure of the paper is loose, the absorption capacity of the paper to the ink will also be strong. Generally speaking, for paper with loose printing structure, such as newsprint, relief paper and other non coating paper, the printing pressure should be lower and the ink viscosity should be lower. For paper with compact printing structure, such as coated paper, the printing pressure can be appropriately higher, and the ink viscosity can also be slightly higher. The second stage is to leave the embossing area from the paper until the ink is completely dry. This stage mainly depends on the capillary action of the paper to absorb the ink, which is called the free penetration stage.

濟(jì)南書(shū)刊雜志印刷

在這個(gè)階段，連結(jié)料從油墨整體中分離出來(lái)，通過(guò)小孔隙和紙張纖維粗糙的表面，以相當(dāng)慢的速度進(jìn)入紙張內(nèi)部。因而這個(gè)過(guò)程實(shí)際是連結(jié)料從油墨向紙張孔隙遷移的過(guò)程，因?yàn)檫B結(jié)料從油墨整體中分離出來(lái)，將會(huì)改變保留在紙面墨膜的結(jié)膜性質(zhì)，墨跡的固著與干燥也要在這個(gè)過(guò)程中完成。

At this stage, the binder is separated from the ink as a whole and enters the interior of the paper at a rather slow speed through small pores and the rough surface of the paper fiber. Therefore, this process is actually the migration of the binder from the ink to the paper pores, because the separation of the binder from the ink as a whole will change the conjunctival properties of the ink film retained on the paper, and the fixation and drying of the ink should also be completed in this process.

在這個(gè)階段，紙張對(duì)油墨的吸收速率決定著印刷品的光澤度，以及是否會(huì)發(fā)生透印、粉化等現(xiàn)象。當(dāng)油墨轉(zhuǎn)移到紙張上時(shí)，隨著時(shí)間的延長(zhǎng)，低分子的連結(jié)料(溶劑)將開(kāi)始向紙層內(nèi)滲透，這樣紙面上油墨層中的溶劑含量就會(huì)下降，油墨黏性增大，墨層產(chǎn)生凝結(jié)。紙張的吸墨性取決于紙張毛細(xì)管的數(shù)量和毛細(xì)管直徑的大小。紙張是一種多孔材料，紙張內(nèi)部的纖維與纖維之間、纖維與填料之間以及顏料粒子之間都存在著許多大小不等的間隙，這些間隙就相當(dāng)于許許多多的毛細(xì)管。

At this stage, the absorption rate of the paper to the ink determines the gloss of the printed matter, and whether there will be through printing, pulverization and so on. When the ink is transferred to the paper, with the extension of time, the low molecular binder (solvent) will begin to penetrate into the paper layer, so that the solvent content in the ink layer on the paper will decrease, the ink viscosity will increase, and the ink layer will condense. The ink absorption of paper depends on the number of paper capillaries and the diameter of capillaries. Paper is a porous material. There are many gaps of different sizes between fibers, between fibers and fillers and between pigment particles in the paper. These gaps are equivalent to many capillaries.

在這些毛細(xì)管的作用下，可以吸收油墨中的連結(jié)料，而且毛細(xì)管的直徑越粗，對(duì)油墨的吸收速度就越快，因此，紙張的孔隙結(jié)構(gòu)決定了其對(duì)油墨的吸收性。紙張?jiān)绞杷?，孔隙越大，吸墨性也越?qiáng)。比如新聞紙比較疏松，具有較強(qiáng)的吸墨性，因此轉(zhuǎn)移在新聞紙上的油墨固著很快，有利于印刷速度的提高。

Under the action of these capillaries, the binder in the ink can be absorbed, and the thicker the diameter of the capillaries, the faster the absorption of the ink. Therefore, the pore structure of the paper determines its absorption of the ink. The looser the paper, the larger the pore, and the stronger the ink absorption. For example, newsprint is relatively loose and has strong ink absorption, so the ink transferred on newsprint is fixed quickly, which is conducive to the improvement of printing speed.

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