Recording paper coated with microscopic capsules of coloring material, capsules and method of making

• US 3,016,308 A
• Filed: 08/06/1957
• Issued: 01/09/1962
• Est. Priority Date: 08/06/1957
• Status: Expired due to Term

• Current Assignee: Norman Macaulay
• Original Assignee: Norman Macaulay
• Inventors: Macaulay, Norman
• Application Number:
  US03/676,574
• Time in Patent Office: 1,617 Days
• US Class Current: 503/200
• CPC Class Codes: B01J 13/125 by evaporation of the solvent apparatus therefor B01J13/043
• CPC Class Codes: B41M 5/165 characterised by the use of microcapsules; Special solvents for incorporating the ingredients
• CPC Class Codes: Y10S 101/29 Printing involving a color-forming phenomenon
• CPC Class Codes: Y10S 521/92 Cellular product containing a dye or pigment
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material
• CPC Class Codes: Y10T 428/2984 Microcapsule with fluid core [includes liposome]
• CPC Class Codes: Y10T 428/2987 Addition polymer from unsaturated monomers only
• CPC Class Codes: Y10T 428/2989 Microcapsule with solid core [includes liposome]

Claims

1. A PROCESS FOR PRODUCING A FREE-FLOWING POWDER OF MICROSCOPIC DISCRETE RUPTURABLE CAPSULES COMPRISING LIQUID DROPLETS ENCAPSULATED WITHIN AN OUTER RUPTURABLE SHELL OF FILM-FORMING MATERIAL, SAID ENCAPSULATING OUTER SHELL BEING FORMED DIRECTLY BY EVAPORATION FORCES IN THE SOLVENT OF A FILM-FORMER SOLUTION OF A NON-IONIZABLE WATER-SOLUBLE FILM-FORMER WHICH COMPRISES THE CONTINUOUS PHASE OF SUSPENDED MINUTE PARTICLES OF AN EMULSION, THE DISCONTINUOUS PHASE OF WHICH EMULSION COMPRISES THE LIQUID DROPLETS AND BETWEEN ABOUT 23% AND 80% BY WEIGHT OF THE CAPSULES, WHICH PROCESS COMPRISES PRODUCING AN EMULSION OF THE LIQUID DROPLETS IN A FILM-FORMER SOLUTION IN WHICH THE LATTER FORMS THE CONTINUOUS PHASE AND IS SUBSTANTIALLY IN-