Fluororesin coating film
View Patent ↗A fluororesin coating film for improved permeation resistance that maintains excellent wear resistance and also products containing such film. The fluororesin coating has at least two layers that are formed on a substrate where at least one of the layers contains filler with a new Mohs hardness of ≧7 and a tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer and tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer layer directly below the layer described above.
1. A fluororesin coating film comprising:
a primer layer formed on a substrate;
an intermediate layer formed on said primer layer, wherein said intermediate layer comprises a first melt-fabricable fluoropolymer and is essentially free from the presence of filler; and
a topcoat layer formed on said intermediate layer, wherein, said topcoat layer comprises a filler with a new Mohs hardness of 7 or higher and a second melt-fabricable fluoropolymer.
2. A fluororesin coating film according to claim 1 , wherein said first melt-fabricable fluoropolymer comprises tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer.
3. The fluororesin coating film according to claim 2 , characterized in that the filler having a new Mohs hardness of 7 or higher has at least one substance selected from the group consisting of diamond powder, corundum powder, quartz rock powder, man-made diamond powder, boron nitride, boron carbide, silicon carbide, fused alumina, and silica powder.
4. The fluororesin coating film according to claim 1 , characterized in that the primer layer contains a fluororesin.
5. A product having a fluororesin coating film described in any of claim 1 , 2 , 3 or 4 .
6. A product according to claim 5 , wherein the product is a cooking utensil.
7. A fluororesin coating film according to claim 1 , wherein said second melt-fabricable fluoropolymer comprises tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer.