| 摘要 |
<p>A cloth-like, soft paper material, impregnated lightly or wholly with an anionic surfactant such as alkylbenzolsulphonate, is enclosed in a moisture-proof, easily-torn envelope, forming a spectacle polishing cloth. Between the zone impregnated with the surfactant and the dry zone of the paper, a sepg. line is formed. This consists of a polyvinyl resin in a rapidly vaporising solvent which penetrates the paper and closes the pores. The sepg. line may also be a synthetic film to each end of which a paper is fastened. The envelope may be of waxed paper or synthetic film, and may hold the papers in two separate compartments. The cloth is quite convenient to carry and facilitates the cleaning of spectacles badly smeared with grease.</p> |
