| 摘要 |
PURPOSE:To obtain a superior base paper for a diazo photosensitive material free from uneven density, and grains, by pressing the base paper with a sizing soln. contg. polyethylene glycol having a specified average mol.wt. range. CONSTITUTION:A base paper is coated with a sizing soln. contg. 1,000-3,000 average mol.wt. polyethylene glycol alone or together with starch, urea resin, or the like weighing about half said glycol, with an amt. of size attached controlled to 7.5X10<-4>-3g/m<2>. This surface-sized base paper for the diazo photosensitive material is, preferably, <=8-15g/m<2> in cup size value measured by the JIS P8140 30sec contact method using an aq. citrate soln. controlled to 2 in pH. Even when a base paper is made not with a long screen paper making machine but with a twin wire screen paper making machine, use of said sizing permits a diazo photosensitive base paper free from uneven density, and grains independent of a one-component type or two-component type diazo photosensitive paper, and a developing process of dry type, or wet type, or amine developing type. |
