US 12,486,407 B2
Powder coating material
Hiroshi Yamamura, Tokyo (JP)
Assigned to SUMITOMO BAKELITE CO., LTD., Tokyo (JP)
Appl. No. 18/014,669
Filed by SUMITOMO BAKELITE CO., LTD., Tokyo (JP)
PCT Filed Aug. 20, 2020, PCT No. PCT/JP2020/031411
§ 371(c)(1), (2) Date Jan. 5, 2023,
PCT Pub. No. WO2022/024399, PCT Pub. Date Feb. 3, 2022.
Claims priority of application No. 2020-130536 (JP), filed on Jul. 31, 2020.
Prior Publication US 2023/0312938 A1, Oct. 5, 2023
Int. Cl. C09D 7/61 (2018.01); C09D 5/03 (2006.01); C09D 7/40 (2018.01); C09D 7/63 (2018.01); C09D 163/00 (2006.01)
CPC C09D 5/031 (2013.01) [C09D 5/035 (2013.01); C09D 7/61 (2018.01); C09D 7/63 (2018.01); C09D 7/69 (2018.01); C09D 7/70 (2018.01); C09D 163/00 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A powder coating material comprising:
a particulate thermosetting resin composition comprising an epoxy resin, a curing agent, and an inorganic filler; and
inorganic particles other than the inorganic filler,
wherein an average particle diameter d50 of the inorganic particles, which is measured by a laser diffraction method, is equal to or more than 1 nm and equal to or less than 100 nm,
wherein a content of the inorganic particles in the powder coating material is equal to or more than 0.01% by mass and equal to or less than 3.0% by mass with respect to the entire powder coating material,
wherein a particle diameter d90 of the thermosetting resin composition, which is measured by a laser diffraction method, is equal to or more than 55 μm and equal to or less than 200 μm,
wherein a flow-rate change index R of the powder coating material, which is calculated by the following expression (ii), is equal to or more than 0% and equal to or less than 26%,
R=X(0)-X(15)  (ii),
wherein in the expression (ii), the X(0) is a flow rate measured before storage of the powder coating material, and the X(15) is a flow rate measured after the storage of the power coating material at 40° C. for 15 days,
wherein the X(0) is equal to or more than 15% and equal to or less than 60%,
wherein the X(0) and the X(15) are measured by following procedures (1) to (4),
(1) 0.5 g of the powder coating material is placed in a 10 mmo molding die, and pressure-molded at 20 kgf for 10 seconds to produce a cylindrical sample to measure a diameter D0 of the cylindrical sample,
(2) after measuring the diameter D0, the cylindrical sample is placed on a 70 mm×150 mm×0.8 mm SPCC plate, and allowed to stand in a hot air dryer at 150° C. for 30 minutes,
(3) a diameter D1 at a contact surface of the cylindrical sample with the SPCC plate after the allowing to stand is measured, and
(4) D0 and D1 described above are measured before the storage (t=0 days) and after the storage at 40° C. for 15 days (t=15 days), and each of the X(0) and the X(15) is calculated based on the following expression (i).
X(t)(%)=(D1−D0)/D0×100  (i),