EP 0975692 A1 20000202 - CONTROLLED DEGRADATION COATINGS AND A METHOD FOR THEIR MANUFACTURE
Title (en)
CONTROLLED DEGRADATION COATINGS AND A METHOD FOR THEIR MANUFACTURE
Title (de)
BESCHICHTUNG ZUM KONTROLLIERTEN ABBAU UND VERFAHREN ZU IHRER HERSTELLUNG
Title (fr)
REVETEMENTS A DEGRADATION REGULEE ET PROCEDE DE FABRICATION DE CES DERNIERS
Publication
Application
Priority
- IE 9800028 W 19980415
- IE S970278 A 19970415
Abstract (en)
[origin: WO9846668A1] A coating for a biodegradable article comprises a hydratable coating or a chemically or physically discontinuous coating. Imperfections in the coating, which may comprise pores in the coating, enable water to penetrate to the underlying surface of the water soluble article. The nature and extent of the imperfections permits the rate of penetration of the coating by water to be controlled. Alternatively, the coating is a hydratable coating which swells and tears on hydration to expose the underlying article to moisture. By these means, the article can be protected from premature dissolution during its normal working life, but will degrade on disposal to waste, when the surface coating will degrade to permit water to reach and dissolve the underlying article. Typically, the body of the article comprises water soluble, biodegradable polyvinyl alcohol or polyvinylalcohol/polyvinylacetate copolymer. Chemical/physical discontinuity may be achieved by over-coating a surface already covered with a physically flawed coating with a hydratable coating.
IPC 1-7
IPC 8 full level
C08J 7/043 (2020.01); C08J 7/046 (2020.01)
CPC (source: EP US)
C08J 7/0427 (2020.01 - EP); C08J 7/043 (2020.01 - EP US); C08J 7/046 (2020.01 - EP US); C08J 2329/04 (2013.01 - EP)
Citation (search report)
See references of WO 9846668A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
WO 9846668 A1 19981022; AU 7074998 A 19981111; CA 2286724 A1 19981022; EP 0975692 A1 20000202; IE S80667 B2 19981118; IE S970278 A2 19981021
DOCDB simple family (application)
IE 9800028 W 19980415; AU 7074998 A 19980415; CA 2286724 A 19980415; EP 98917566 A 19980415; IE S970278 A 19970415