申请人:MINNESOTA MINING AND MANUFACTURING COMPANY
公开号:EP0358351A2
公开(公告)日:1990-03-14
Adhesively edge-padded stack of carbonless copy paper better separates upon fanning into collated sets when a thin layer of hot-melt adhesive is used for the edge-padding. As in the prior art, the outer surfaces of each set should have a release coating such as a fluorocarbon. The layer of hot-melt adhesive includes, by weight:
20-50% thermoplastic copolymer,
15-50% tackifying resin, and
20-60% wax having a melting point of at least 60°C.
As soon as the adhesive has cooled below its softening point, the stack can be fanned, thus breaking it into sets. Fanning can usually be performed within 45 seconds, because there is no need to wait for the adhesive to dry as has been necessary with the aqueous adhesives that have been used in the prior art. Preferably at least 20% by weight of the adhesive is a paraffin wax that is C₃₅-C₇₀ substantially straight-chain hydrocarbon.
当使用一层薄薄的热熔胶作为边缘衬垫时,无碳复写纸的边缘衬垫能更好地将复写纸分开。与现有技术一样,每套纸的外表面都应有一层离型涂层,如碳氟化合物。按重量计,热熔胶层包括
20-50% 热塑性共聚物、
15-50% 增粘树脂,以及
20-60% 熔点至少为 60°C 的蜡。
当粘合剂冷却到软化点以下时,就可以将堆叠的粘合剂扇开,从而将其打碎。通常可以在 45 秒内完成煽风,因为不需要像现有技术中使用的水性粘合剂那样等待粘合剂干燥。按重量计,粘合剂中至少 20% 的石蜡最好是 C₃₅-C₇₀ 大致为直链烃的石蜡。