Formed paper article, local region coating method, and coating device

Abstract

A raised resin portion 8, 9 is formed by thermally spraying a powdered resin on a local portion such as a bonding step portion of a cup-shaped formed paper article 1 to improve sealing performance of the formed paper article and form a resin coating layer 60 including a scorching-preventing substance on a local region where scorching tends to occur during heating in a microwave oven. The raised resin portion is formed on the local region by intermittently discharging the resin powder from a tank with a shutter device and repeatedly thermally spraying the resin powder on the local region with a pressurized gas.

1 . A formed paper article having an opening, wherein a raised resin portion is formed on a local portion by thermally spraying a coating material configured of a powder mainly composed of a synthetic resin. 
     
     
         2 . The formed paper article according to  claim 1 , wherein the local portion is at least a bonding step portion of a peripheral edge of the opening of a cup-shaped formed paper article, and the step portion is buried by the raised resin portion. 
     
     
         3 . The formed paper article according to  claim 1 , wherein the local portion is a bonding step portion of a body of the formed paper article, and a paper edge in the bonding portion is coated with the raised resin portion. 
     
     
         4 . The formed paper article according to  claim 1 , wherein the formed paper article is a drawn article mainly composed of paper, the local portion is an entire periphery of an opening flange surface, and wrinkles on the opening flange surface are coated by the raised resin portion. 
     
     
         5 . The formed paper article according to  claim 1 , wherein the raised resin portion is formed by thermally spraying a heat-adhesive resin powder and has an average coating thickness of 0.3 mm or less. 
     
     
         6 . The formed paper article according to  claim 1 , wherein the formed paper article is a formed paper container adapted to heating in a microwave oven, wherein a resin coating layer including a scorching-preventing substance is formed on a local region of the formed paper container. 
     
     
         7 . The formed paper article according to  claim 6 , wherein the resin coating layer is formed by thermally spraying a powder in which a scorching-preventing substance powder is mixed with a resin powder. 
     
     
         8 . The formed paper article according to  claim 7 , wherein the scorching-preventing substance powder is an inorganic substance with a relative dielectric constant of 2 or less. 
     
     
         9 . A coating method for coating a local region of an object with a coating material mainly composed of a synthetic resin, wherein the coating material is a powder mainly composed of a synthetic resin, and the powder is intermittently thermally sprayed on the local region. 
     
     
         10 . The coating method according to  claim 9 , wherein in the thermal spraying, the powder is quantitatively discharged, pumped by a pressurized gas, merged with a heating gas, and intermittently thermally sprayed on the local region. 
     
     
         11 . The coating method according to  claim 10 , wherein the heating gas is hot air, heats the synthetic resin powder close to a melting point, and partially melts the powder. 
     
     
         12 . The coating method according to  claim 9 , wherein the local region to be coated in the object is preheated. 
     
     
         13 . A coating device for coating a local region of an object with a coating material mainly composed of a synthetic resin, wherein the coating material is a powder, the coating device comprises a tank for supplying the powder, a thermal spray nozzle communicating with a lower end of the tank, and a quantitative discharge shutter device provided between a lower end opening of the tank and the thermal spray nozzle, and the powder is quantitatively discharged from the tank by the quantitative discharge shutter device, merged with a heating gas, and thermally sprayed from the thermal spray nozzle. 
     
     
         14 . The coating device according to  claim 13 , wherein the quantitative discharge shutter device is composed of a rotating body provided across an outlet opening of the tank, a metering chamber facing the outlet opening of the tank is provided in the rotating body, a valve is provided that communicates with a gas supply port of the metering chamber and supplies a pressurized gas to the metering chamber, the rotating body can be rotated intermittently between a metering position and a thermal spraying position, at the metering position the powder is quantitatively metered facing the outlet opening of the tank, at the spraying position, the metering chamber faces the thermal spray nozzle, the pressurized gas is supplied from the valve to the metering chamber, and the powder is pumped into the thermal spray nozzle.