| 摘要 |
<p>374,922. Proofing against water and chemicals. FINLAY, A. H., Willesden, Holywood, Co. Down, Northern Ireland. March 12, 1931, Nos. 7618 and 26928. [Class 140.] Materials such as cardboard and pulpboard used for containers for water-bearing substances such as soft soap are waterproofed and protected against the action of such substances by applying to the materials a waterproofing agent such as a fat or wax and a protecting substance which does not react either with the waterproofing agent or with the cardboard. The treatment may be applied either before or after the material is made into containers. The protecting agents are preferably watermiscible or soluble and include colloidal clay, starch, stearine and iodine. They may be applied either together with the waterproofing- agent or separately on that surface which will be in contact with the water-bearing substances. Examples describe impregnation by immersion in a molten mixture of the waterproofing and protecting agents, in which air may be incorporated, or by introducing the mixture into the containers and pouring out when the temperature has fallen nearly to the setting point of the wax. According to the first Provisional Specification the interior of the container is treated. with substances such as starch, dextrin, farina, gum or glue and the whole or the exterior only then coated with wax. The second Provisional Specification describes also lining the container with fine white corrugated paper and then soaking in molten wax. Reference has been directed by the Comptroller to Specifications 18136/06, 134,010, 202,314,. 302,367 and 319,517, [all in Class 140, Waterproof &c. fabrics].</p> |
