US 11,999,925 B2
Plastic cleaning method using dispersant copolymer
Scott Backer, Phoenixville, PA (US); and Paul Mercando, Pennsburg, PA (US)
Assigned to Rohm and Haas Company, Collegeville, PA (US)
Appl. No. 17/057,263
Filed by Rohm and Haas Company, Collegeville, PA (US)
PCT Filed Jun. 10, 2019, PCT No. PCT/US2019/036260
§ 371(c)(1), (2) Date Nov. 20, 2020,
PCT Pub. No. WO2020/005517, PCT Pub. Date Jan. 2, 2020.
Claims priority of provisional application 62/690,461, filed on Jun. 27, 2018.
Prior Publication US 2021/0309945 A1, Oct. 7, 2021
Int. Cl. B08B 3/04 (2006.01); C11D 1/66 (2006.01); C11D 3/02 (2006.01); C11D 3/20 (2006.01); C11D 3/36 (2006.01); C11D 3/37 (2006.01)
CPC C11D 1/66 (2013.01) [C11D 3/2082 (2013.01); C11D 3/2093 (2013.01); C11D 3/361 (2013.01); C11D 3/3757 (2013.01); C11D 2111/18 (2024.01)] 7 Claims
 
1. A plastic cleaning method for cleaning a plastic article in an automatic dishwashing machine, comprising:
selecting an automatic dishwashing composition for cleaning plastic, wherein the automatic dishwashing composition, comprises:
a builder, wherein the builder includes a mixture of at least one carbonate and at least one citrate;
a phosphonate;
a nonionic surfactant; and
a dispersant polymer comprising:
(a) 85 to 91 wt % of structural units of formula I

OG Complex Work Unit Chemistry
wherein each R1 is independently selected from a hydrogen and a —CH3 group; and
(b) 9 to 15 wt % of structural units of formula II

OG Complex Work Unit Chemistry
wherein each R2 is independently selected from an alkyl group with at least 4 carbon atoms and wherein each R3 is independently selected from a hydrogen and a methyl group;
providing a plastic article, wherein the plastic article includes a polystyrene tumbler; and,
applying the automatic dishwashing composition to the plastic article.