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Soil redeposition versus deposition tests in evaluation of laundry detergents
Author(s) -
Hensley James W.
Publication year - 1965
Publication title -
journal of the american oil chemists' society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.512
H-Index - 117
eISSN - 1558-9331
pISSN - 0003-021X
DOI - 10.1007/bf02632462
Subject(s) - carboxymethyl cellulose , polyvinylpyrrolidone , polyethylene glycol , polyvinyl alcohol , laundry , deposition (geology) , chemistry , peg ratio , sodium , chemical engineering , sediment , organic chemistry , waste management , geology , paleontology , finance , engineering , economics
Whiteness retention results obtained with a soil 舠deposition舡 type test, in which soil material as such is added to the detergent bath, are found to be in contradiction to those obtained with soil 舠redeposition舡 tests, in which clean and soiled cloth are washed together. A carbon soil deposition test shows polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) to be superior to sodium carboxymethyl cellulose (CMC), and a polyethylene glycol (PEG) equal to CMC in improving whiteness retention results with a built anionic detergent, with pronounced synergistic effects for PVA‐CMC and PEG‐CMC combination. In contrast, the redeposition tests, employing either carbon black or tagged clay soil, show only the CMC to be effective, the nonionic polymers being ineffective alone and in combinations with CMC. Further, in evaluating the effect of tripolyphosphate builder with an alkylbenzene sulfonate, the deposition and redeposition tests give quite contradictory results. The observed contradictions cast considerable doubt on the validity of the usual carbon soil deposition tests, and emphasize the need for further study of whiteness retention test methods.