Wall-sealing treatment for minute capsules and minute capsules having walls of sealed polymeric material

Claim 2

The process of claim 2 wherein the liquid is substantially cyclohexane.

Claim 3

The process of claim 3 wherein the wax is substantially paraffin wax.

Claim 4

A process for treating, in the latter stages of en masse capsule manufacture carried on in a liquid vehicle, solveNt-swollen polymeric material composing the walls of capsules, said process including the steps of a. establishing a slurry by dispersing the capsules having solvent-swollen walls in a liquid solvent-miscible solution of wax, said solution penetrating the swollen capsule walls, b. separating the capsules from the wax-containing liquid that is free after substantial solution equilibrium has been attained, and c. removing the residual liquid from the capsule walls.

Claim 5

The process of claim 5 wherein the capsule walls consist substantially of ethyl cellulose polymeric material.

Claim 6

The process of claim 6 wherein the liquid is substantially cyclohexane.

Claim 7

The process of claim 7 in which the wax is substantially paraffin wax.

Claim 8

A minute capsule having, as a wall, hydrophobic polymeric material, which material has been permeated throughout with a waxy material.

Claim 9

The capsule of claim 9 wherein the hydrophobic wall material is ethyl cellulose polymeric material.

Claim 10

The capsule of claim 9 wherein the waxy material is substantially paraffin wax.

Claim 11

A process of treating ethyl cellulose-walled capsules to seal the walls to penetration by a leaching liquid, comprising the steps of a. soaking the capsules in a solution of waxy material in a solvent that swells the ethyl cellulose walls for a time until an equilibrium has been attained; and b. recovering the capsules from said solution and drying them of solvent, leaving the wax in the walls, which walls, by consequent shrinking, hold the wax as in a matrix.