| 摘要 |
PURPOSE:To contrive improvement in the strength of an unburned lead for a pencil, by using a skeleton-forming material together with a montmorillonite clay containing polymerization materials between its layers, and polymerizing the skeleton-forming material to unite with the polymerization materials. CONSTITUTION:An unburned lead for a pencil is obtained by using a filler comprising a montmorillonite clay containing polymerization materials between its layers and a skeleton-forming material comprising an organic material which will unite with the polymerization materials and is polymerizable, and uniting the polymerization materials with the skeleton-forming material. The above- mentioned polymerization materials comprise a polymerization initiator, a polymerization accelerator, a curing agent, etc., which assist the polymerization (including crosslinking) of the organic material and unite therewith. Examples of the skeleton-forming material include acrylonitrile, styrene, methyl methacrylate, and vinyl acetate. Examples of the montmorillonite clay include calcium bentonite, sodium bentonite, and high-purity products thereof.
|
