Coating method with precure and apparatus therefor

Claim 1

A METHOD FOR THE PRODUCTION OF A UNIFIED, ADHERENT COATING OF HEAT-FUSIBLE MATERIAL UPON ONLY A PORTION OF A WORKPIECE HAVING PROXIMATE FIRST AND SECOND ZONES IN HEAT-CONDUCTIVE CONTACT WITH ONE ANOTHER, COMPRISING THE STEPS OF: A. PRODUCTING A CLOUD OF ELECTROSTATICALLY CHARGED SOLID PARTICLES OF HEAT-FUSIBLE RESINOUS MATERIAL, B. EXPOSING SAID WORKPIECE TO SAID CHARGED PARTICLES WITH SAID WORKPIECE CHARGED EFFECTIVELY OPPOSITE THERETO TO CAUSE A LAYER OF SAID PARTICLES TO DEPOSIT UPON SAID FIRST AND SECOND ZONES THEREOF, C. HEATING SAID FIRST ZONE OF SAID WORKPIECE TO A RELATIVELY HIGH TEMPERATURE ABOVE AMBIENT WHILE SIMULTANEOUSLY COOLING SAID SECOND ZONE THEREOF TO CAUSE AT LEAST PARTIAL FUSION AND COHEREHCE OF SAID PARTICLES ON SAID FIRST ZONE WHILE MAINTAINING SAID SECOND ZONE AT A RELATIVELY LOWTEMPERATURE SUBSTANTIALLY BELOW SAID RELATIVELY HIGH TEMPERATURE TO SUBSTANTIALLY PREVENT FUSION AND COHERENCE OF PARTICLES ON SAID SECOND ZONE TO THEREBY FACILITATE REMOVAL THEREFORM, D. THEREAFTER REMOVING FROM SAID SECOND ZONE ANY OF SAID PARTICLES OF RESINOUS MATERIAL REMAINING THEREON, SAID SIMULTANEOUS HEATING AND COOLING STEP PRODUCING A RELATIVELY STEEP TEMPERATURE GRADIENT BETWEEN SAID FIRST AND SECOND ZONES SO THAT THE MARGINS OF SAID LAYER OF PARTICLES ON SAID FIRST ZONE ARE RELATIVELY SHARPLY DEFINED.

Claim 2

A METHOD FOR THE PRODUCTION OF A UNIFIED, ADHERENT COATING OF HEAT-FUSIBLE MATERIAL UPON ONLY A PORTION OF A WORKPIECE HAVING PROXIMATE FIRST AND SECOND ZONES IN HEAT-CONDUCTIVE CONTACT WITH ONE ANOTHER, COMPRISING THE STEPS OF: A. PRODUCTING A CLOUD OF ELECTROSTATICALLY CHARGED SOLID PARTICLES OF HEAT-FUSIBLE RESINOUS MATERIAL, B. EXPOSING SAID WORKPIECE TO SAID CHARGED PARTICLES WITH SAID WORKPIECE CHARGED EFFECTIVELY OPPOSITE THERETO TO CAUSE A LAYER OF SAID PARTICLES TO DEPOSIT UPON SAID FIRST AND SECOND ZONES THEREOF, C. HEATING SAID FIRST ZONE OF SAID WORKPIECE TO A RELATIVELY HIGH TEMPERATURE ABOVE AMBIENT WHILE SIMULTANEOUSLY COOLING SAID SECOND ZONE THEREOF TO CAUSE AT LEAST PARTIAL FUSION AND COHEREHCE OF SAID PARTICLES ON SAID FIRST ZONE WHILE MAINTAINING SAID SECOND ZONE AT A RELATIVELY LOWTEMPERATURE SUBSTANTIALLY BELOW SAID RELATIVELY HIGH TEMPERATURE TO SUBSTANTIALLY PREVENT FUSION AND COHERENCE OF PARTICLES ON SAID SECOND ZONE TO THEREBY FACILITATE REMOVAL THEREFORM, D. THEREAFTER REMOVING FROM SAID SECOND ZONE ANY OF SAID PARTICLES OF RESINOUS MATERIAL REMAINING THEREON, SAID SIMULTANEOUS HEATING AND COOLING STEP PRODUCING A RELATIVELY STEEP TEMPERATURE GRADIENT BETWEEN SAID FIRST AND SECOND ZONES SO THAT THE MARGINS OF SAID LAYER OF PARTICLES ON SAID FIRST ZONE ARE RELATIVELY SHARPLY DEFINED.

Claim 8

A method for the production of a unified, adherent coating of heat-fusible material upon only a portion of a work-piece having proximate first and second zones in heat-conductive contact with one another, comprising the steps of: a. producing a cloud of electrostatically charged solid particles of heat-fusible resinous material; b. exposing said workpiece to said charged particles with said workpiece at about ambient temperature and charged effectively opposite to said particles to cause a layer thereof to deposit upon said first and second zones of said workpiece; c. thereafter heating said first zone of said workpiece to a relatively high temperature above ambient while simultaneously cooling said second zone thereof to cause at least partial fusion and coherence of said particles on said first zone while maintaining said second zone at a relatively low temperature substantially below said relatively high temperature to substantially prevent fusion and coherence of particles on said second zone to thereby facilitate removal therefrom; and d. thereafter removing from said second zone any of said particles of resinous material remaining thereon, said simultaneous heating and cooling step producing a relatively steep temperature gradient between said first and second zones, so that the margins of said layer of particles on said first zone are relatively sharply defined, said step (d) being effected immediately after said step (c).

Claim 9

A method for the production of a unified, adherent coating of heat-fusible material upon only a portion of a work-piece having proximate first and second zones in heat-conductive contact with one another, comprising the steps of: a. producing a cloud of electrostatically charged solid particles of heat-fusible resinous material; b. exposing said workpiece to said charged particles with said workpiece at about ambient temperature and charged effectively opposite to said particles to cause a layer thereof to deposit upon said first and second zones of said workpiece; c. thereafter heating said first zone of said workpiece to a relatively high temperature above ambient while simultaneously cooling said second zone thereof to cause at least partial fusion and coherence of said particles on said first zone while maintaining said second zone at a relatively low temperature substantially below said relatively high temperature to substantially prevent fusion and coherence of particles on said second zone to thereby facilitate removal therefrom; and d. thereafter removing from said second zone any of said particles of resinous material remaining thereon, said simultaneous heating and cooling step producing a relatively steep temperature gradient between said first and second zones, so that the margins of said layer of particles on said first zone are relatively sharply defined, said step (d) being effected immediately after said step (c).