Gum up to apply gum Arabic or similar solution to a lithographic surface to protect it from oxidation and grease.

在柯式印版上涂上一层阿拉伯胶或类似的胶体以防止氧化或沾染油脂。

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Gum up: to apply gum Arabic or similar solution to a lithographic surface to protect it from oxidation and grease. It also increases the hydrophilic property of the non-image areas.

上胶：在柯式印版上涂上一层阿拉伯胶或类似的胶体以防止氧化或沾染油脂。它并增强非印纹部份的亲水性。

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