公开(公告)号：US5244297A

公开(公告)日：1993-09-14

申请号：US25825

申请日：1993-03-03

申请人： Jacques Bachelet ,  Philippe Chavatte ,  Guy Chochoy ,  Jose Duez ,  Claude Fouble ,  Didier Lange

发明人： Jacques Bachelet ,  Philippe Chavatte ,  Guy Chochoy ,  Jose Duez ,  Claude Fouble ,  Didier Lange

IPC分类号： B29C47/06 ,  B43K19/16

CPC分类号： B29C47/128 ,  B43K19/16 ,  B29C47/0016

摘要： According to the invention, the writing or coloring pencil is obtained by tri-extrusion of three thermoplastic materials forming the lead material, the expanded wood material and an intermediate protective layer, containing no expanding agent, which is compatible with the lead material and the wood material and has a melting point which is equal to or higher than the melting points of the lead material and the wood material. The three co-extruded materials all contain in particular the same basic component, such as for example a polystyrene-methacrylate copolymer. The protective layer can be of a different color from the other two layers. The writing or coloring pencil with protective casing between the lead and the expanded wood, all three being in thermoplastic material, is, in particular a pencil with soft or extra-soft lead.

摘要翻译： 根据本发明，书写或着色铅笔是通过三种热塑性材料的三次挤出而形成的，该三种热塑性材料形成铅材料，膨胀木材和不含膨胀剂的中间保护层，其与铅材料和木材相容 并且具有等于或高于引线材料和木材材料的熔点的熔点。 三种共挤出材料都特别包含相同的基本组分，例如聚苯乙烯 - 甲基丙烯酸酯共聚物。 保护层可以是与其他两层不同的颜色。 在铅和扩展木材之间的保护套的书写或着色铅笔，全部三种是热塑性材料，特别是铅笔，软铅或超软铅笔。