US 12,331,270 B2
Solvent mixture for the removal of silicone conformal coatings from a printed circuit board
Donato Polignone, Emeryville, CA (US); and Stephen Utschig-Samuels, Emeryville, CA (US)
Assigned to NuGeneration Technologies, LLC, Emeryville, CA (US)
Filed by NuGeneration Technologies, LLC, Emeryville, CA (US)
Filed on Dec. 28, 2023, as Appl. No. 18/399,401.
Application 18/399,401 is a continuation of application No. 17/812,969, filed on Jul. 15, 2022, granted, now 11,891,592.
Application 17/812,969 is a continuation of application No. 16/704,208, filed on Dec. 5, 2019, granted, now 11,414,631, issued on Aug. 16, 2022.
Claims priority of provisional application 62/852,950, filed on May 24, 2019.
Prior Publication US 2024/0132810 A1, Apr. 25, 2024
Int. Cl. C11D 9/36 (2006.01); B08B 3/08 (2006.01); C09D 9/00 (2006.01); C11D 7/50 (2006.01); C11D 17/00 (2006.01)
CPC C11D 7/5031 (2013.01) [B08B 3/08 (2013.01); C09D 9/005 (2013.01); C11D 7/5009 (2013.01); C11D 7/5022 (2013.01); C11D 17/0043 (2013.01); C11D 2111/22 (2024.01)] 7 Claims
 
1. A method of removing a silicone conformal coating for replacing an electrical component on a printed circuit board (PCB), the method comprising the steps of:
A) providing a PCB with a first electrical component mounted to the PCB and a silicone conformal coating deposited over the PCB and first electrical component;
B) providing a solvent composition comprising an oxygenated solvent and a siloxane solvent, wherein the siloxane solvent is hexamethyldisiloxane and the oxygenated solvent is selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butylene glycol, dibutylene glycol, tributylene glycol, pentylene glycol, dipentylene glycol, tripentylene glycol, hexylene glycol, dihexylene glycol, trihexylene glycol, heptylene glycol, diheptylene glycol, triheptylene glycol, octylene glycol, dioctylene glycol, trioctylene glycol, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol diacetate, dipropylene glycol dimethyl ether, diethylene glycol ethyl ether, diethylene glycol hexyl ether, diethylene glycol n-butyl ether acetate, ethylene glycol propyl ether, ethylene glycol hexyl ether, ethylene glycol n-butyl ether acetate, triethylene glycol ethyl ether, and ethylene glycol n-butyl ether;
C) using the solvent composition to remove a portion of the conformal silicone coating over the first electrical component; and replacing the first electrical component with a second electrical component after removing the portion of the silicone conformal coating.