Method for cleaning textiles
Detergent or micelle free cleaning media based on detergent free and/or micelle free liquid CO 2 and including from 0.01 to 5% by weight of the formulation of a cleaning additive which is at least one multi-ester having a molecular weight of not more than 750 can be used in dry cleaning of textiles. Desirable cleaning additives are of the formula (1): R 1 (XR 2 ) n where X, R 1 , R 2 , and n have defined meanings, particularly to be esters of multi-carboxylic acids and mono-hydroxy alcohols or esters of mono-carboxylic acids and multi-hydroxy alcohols.
1. A detergent free dry cleaning medium based on liquid CO 2 and including from 0.01 to 5% by weight of the cleaning medium of a cleaning additive which is at least one multi-ester having a molecular weight of not more than 750.
2. A dry cleaning formulation as claimed in claim 1 wherein the multi-ester includes at least one compound of the formula (I):
R 1 (XR 2 ) n (I)
where
X is —C(O)O— or —OC(O)—; such that
where X is —C(O)O—,
R 1 is a direct bond or the residue of a C 1 to C 10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R 2 is a C 1 to C 10 hydrocarbyl group; and
where X is —OC(O)—,
R 1 is or the residue of C 2 to C 10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R 2 is H or a C 1 to C 10 hydrocarbyl group; and
n is from 2 to 5;
the compound having a molecular weight of not more than 750.
3. A dry cleaning formulation as claimed in claim 2 wherein the multi-ester is of the formula (Ia):
R 1a (XR 2a ) n (Ia)
where
X is —C(O)O—;
R 1a is a direct bond or the residue of a C 1 to C 10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R 2a is a C 1 to C 10 hydrocarbyl group.
4. A dry cleaning formulation as claimed in claim 3 wherein the multi-ester is a dimethyl ester of adipic, glutaric or succinic acids or a mixture of such esters.
5. A dry cleaning formulation as claimed in claim 1 wherein the average molecular weight of the multi-ester(s) is from 150 to 300.
6. A dry cleaning formulation as claimed in claim 1 wherein the average ratio of oxygen atoms to carbon atoms in the multi-ester(s) is from 1:1 to 1:5.
7. A dry cleaning formulation as claimed in claim 6 wherein the average ratio of oxygen atoms to carbon atoms in the multi-ester(s) is from 1:1 to 1:1.5.
8. A dry cleaning formulation as claimed in claim 1 wherein the amount of cleaning additive multi-ester present in the cleaning medium is from 0.1 to 0.5% by weight of the cleaning medium.
9. A dry cleaning formulation as claimed in claim 1 which additionally includes at least one fragrance, optical brightener, fabric conditioner, enzyme and/or bleach.
10. A method of dry cleaning which includes contacting textile material with a detergent free dry cleaning medium based on liquid CO 2 and including from 0.01 to 5% by weight of the cleaning medium of a cleaning additive which is at least one multi-ester having a molecular weight of not more than 750.
11. A method as claimed in claim 10 wherein the multi-ester includes at least one compound of the formula (I):
R 1 (XR 2 ) n (I)
where
X is —C(O)O— or —OC(O)—; such that
where X is —C(O)O—,
R1 is a direct bond or the residue of a C1 to C10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R2 is a C1 to C10 hydrocarbyl group; and
where X is —OC(O)—,
R1 is or the residue of C2 to C10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R2 is H or a C1 to C10 hydrocarbyl group; and
n is from 2 to 5;
the compound having a molecular weight of not more than 750.
12. A method as claimed in claim 11 wherein the multi-ester is of the formula (Ia):
R 1a (XR 2a ) n (Ia)
where
X is —C(O)O—;
R 1a is a direct bond or a C 1 to C 10 hydrocarbyl group from which n hydrogen atoms have been removed; and
R 2a is a C 1 to C 10 hydrocarbyl group.
13. A method as claimed in claim 12 wherein the multi-ester is a dimethyl ester of adipic, glutaric or succinic acids or a mixture of such esters.
14. A method as claimed in claim 10 wherein the average molecular weight of the multi-ester(s) is from 150 to 300.
15. A method as claimed in claim 10 wherein the average ratio of oxygen atoms to carbon atoms in the multi-ester(s) is from 1:1 to 1:1.5.
16. A method as claimed in claim 10 wherein the amount of cleaning additive multi-ester present in the cleaning medium is from 0.1 to 0.5% by weight of the cleaning medium.
17. A method as claimed in claim 10 which additionally includes at least one fragrance, optical brightener, fabric conditioner, enzyme and/or bleach.
18. A method as claimed in claim 10 wherein the multi-ester is pre-mixed with liquid CO 2 before contacting the textiles.
19. A method as claimed in claim 10 wherein the cleaning process is carried out at a temperature of from −5 to 25° C.
20. A method as claimed in claim 19 wherein the temperature is from 5 to 20° C.
21. A method as claimed in claim 20 wherein the temperature is from 12 to 15° C.