| 摘要 |
A melamine-formaldehyde resin modified with butyl alcohol is made by mixing melamine with formaldehyde in the presence of trisodium phosphate and heating until an opalescent solution is obtained. On cooling, the portion solidifying is filtered off, stirred with butyl alcohol, toluene and phthalic anhydride, then distilled under reduced pressure. The viscous solution remaining is diluted with ethyl acetate, maleic anhydride added as a hardening agent and films coated with this solution. The coating is hardened by heat with removal of the solvent. Paraffin wax and resins and/or plasticizers may be added to the coating solution. Specification 590,698, [Group VIII], is referred to. |
