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1　丝网鬼影的产生与去除
“鬼影”通常用来描述回收丝网版上的残留图像图案。回收后，许多微小的硬化墨点以及乳剂颗粒粘着在丝壁上，从而影响了下一次的网孔油墨正常传递的能力。最坏的情况下，当丝网版重新进行涂布并曝光生成新图像后，残留图像部分的硬化颗粒就会吸附油墨从而在印品上呈现出模糊的图案。
然而这种油墨/乳剂颗粒通常可以用强力型清洗化学物质如除雾剂来消除。除雾剂分解了丝壁上残留的乳剂，使网孔回复到自然绷张的状态。
还存在另外一种形式的“鬼影”，就是当新的乳剂已涂布并进行了特定的曝光后，用这新的网版图像进行印刷时，模糊的不一致性图案也会在部分连续调区呈现出来。这一问题的原因可推溯到阳片本身上来。
阳片在图像连续区域有不连续的情况，换句话说，图像区域应该有足够的不透明度以阻挡曝光光线的通过，但部分区域会因达不到理想的密度从而使光线到达下层的乳剂层并产生一定实际的曝光量，显影后，就会使应该完全溶墨的网孔部分封堵，从而在印品上产生非必要的印刷图案。解决这一问题的方法是充分利用密度仪的功能，利用它来检测阳片连续调区的最高密度（Dmax)和无密度透光区的最低温度（Dmin).
第三个潜在的原因是网版织物的老旧、磨损。在长期的液压、扩张作用以及清洗与回收过程中，网版丝织物会变得更加破损平板，从而在印刷时，这种局部变形的丝线带来油墨传递特性改变，与完好的部分相比，这些区域就会在印品上形成附加的图案特征。当这种物理损伤时，唯一能做的就是更换网版丝网。
2　四色丝网印刷的最佳网角是多少？
与其它的四色印刷技术相比，丝网印刷的工作流程中更容易引起莫尔纹出现。当在印前工艺中选择各分色版的网角时，就会带来由半色调叠加不当所产生的莫尔纹。
对于刚刚从事丝网印刷的新手来说，所选择的网角通常与胶印工艺的四色网角一致，在部分应用场合，这种选择会达到很好的效果，但在另外一些情况下，这种网角恰好会形成规律性的图案，产生莫尔纹，如再与网线结构产生进一步的加强，从而使欲避免的莫尔纹更加明显。
通常的规律是，当加网线数在50线/英寸以内，而丝网织物本身丝线密度达到355线/英寸或更高，可采用传统的胶印网角（Y＝0度，C＝15度，M＝75度，K＝45度）。低线数下另一种网角选择是，使C、M和K相互保持30度的距离而Y与C保持15度距离，如K＝45度，C＝75度，M＝105度，Y＝90度（或60度）。在这两种情况下，线数低使得网点很大，则丝网本身的织物结构对网点的半色调结构产生的影响是微不足道的。
随着线数的增加，网点尺寸也随之变小，此时就必须旋转整个网角设置使之偏离传述的胶印网角。否则，黄版和黑版的网点角度会和网版织物的纹理产生相干性干涉，从而会产生莫尔纹。丝网印刷最常用的网角设置是，Y＝7.5度，C＝22.5度，M＝82.5度，这组设置适合丝网织物密度在355线数/英寸以上的绝大多数场合。在不同的网孔/半色调线数的组合情况下，这组数字同样可用于检测实际所需网角设置的起始值。

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