Organopolysiloxanes for defoaming aqueous systems
AssigneeGoldschmidt GmbH
InventorsWilfried Knott, Kathrin Lehmann, Martina Lüger, Stefan Silber
Life of this patent
Estimating the term…
Abstract
The invention relates to the use of water-insoluble organopolysiloxane derivatives of the general formula (I) in which the radicals R1 are alkyl radicals, preferably having 1 to 4 carbon atoms or aryl radicals, but at least 80% of the radicals R1 are methyl radicals, and R2 at least once in the molecule has the definition (a) for defoaming aqueous media, especially printing inks and paints.
Claims19
A method for defoaming aqueous media which comprises adding to the aqueous media an organopolysiloxane derivative of the general average formula (I)
- where the radicals
- R1 are alky radicals or aryl radicals, but at least 80% of the radicals R1 are methyl radicals,
- R2 in the molecule are identical or different and have the following definitions:
- in which
- R3 is a hydrogen or alkyl radical,
- R4 is a hydrogen, alkyl or carboxyl radical,
- c is a number from 1 to 20,
- d is a number from 0 to 50,
- e is a number from 0 to 50 or
- (b)
- —(CH2—)fOR5,
- in which
- R5 is a hydrogen, alkyl or carboxyl radical or a dimethylol propane radical containing ether groups if desired, and
- f is a number from 2 to 20 or
- c)
- —(CH2—)g(OC2H4—)h(OC3H6—)i(OC4H8)j(OCH2CH(C6H5))kOK6
- in which
- R6 is a hydrogen, alkyl or carboxyl radical,
- g is a number from 2 to 6,
- h is a number from 0 to 20,
- i is a number from 1 to 50,
- j is a number form 0 to 10,
- k is a number from 0 to 10 or
- (d)
- correspond to the radical R1,
- with the proviso that in the average molecule at least one radical R2 has the definition (a),
- a is a number from 1 to 500,
- b is a number from 0 to 10.
- and wherein the water solubility of the organopolysiloxane is such that it forms a clear solution in water in an amount not more than 20 g/l at 25° C.
A method for defoaming aqueous media which comprise adding to the aqueous media an organopolysiloxane derivative of the general average formula (I)
- where the radicals
- R1 are alkyl radicals having 1 to 4 carbon atoms or aryl radicals, but at least 80% of the radicals R1 are methyl radicals,
- R2 in the molecule are identical or different and have the following definitions:
- in which
- R3 is a hydrogen, alkyl radical
- R4 is a hydrogen, alkyl or carbonyl radical,
- c is a number from 1 to 20,
- d is a number from 0 to 50,
- e is a number from 0 to 50,
- (b)
- —(CH2—)fOR5,
- in which
- R5 is a hydrogen, alkyl or carboxyl radical, or a dimethylol propane radical containing ether groups if desired, and
- f is a number from 2 to 20 or
- c)
- —(CH2—)g(OC2H4—)h(OC3H6—)i(OC4H8)j(OCH2CH(C6H5))kOR6
- in which
- R6 is a hydrogen, alkyl or carboxyl radical,
- g is a number from 2 to 6,
- h is a number from 0 to 20,
- i is a number from 1 to 50,
- j is a number from 0 to 10,
- k is a number from 0 to 10, or
- (d)
- correspond to the radical R1,
- with the proviso that in the average molecule at least one radical R2 has the definition (a),
- a is a number from 1 to 500, and
- b is a number from 0 to 10
- and wherein the water solubility of the organopolysiloxane is such that forms a clear solution in water in an amount not more than 20 g/l at 25° C.
A defoamer emulsion, which comprises from about 5 to about 50% of at least one water-insolule organopolysiloxane derivative of the general average formula (I)
- where the radicals
- R1 are alkyl radicals or aryl radicals, but at least 80% of the radicals R1 are methyl radicals,
- R2 in the molecule are identical or different and have the following definitions:
- in which
- R3 is a hydrogen, alkyl radical
- R4 is a hydrogen, alkyl or carbonyl radical
- c is a number from 1 to 20,
- d is a number from 0 to 50,
- e is a number from 0 to 50,
- (b)
- —(CH2—)fOR5,
- in which
- R5 is a hydrogen, alkyl or carboxyl radical, or a dimethylol propane radical containing ether groups if desired, and
- f is a number from 2 to 20 or
- c)
- —(CH2—)g(OC2H4—)h(OC3H6—)j(OCH2CH(C6H5))kOR6
- in which
- R6 is a hydrogen, alky or carboxyl radical,
- g is a number from 2 to 6,
- h is a number from 0 to 20,
- i is a number from 1 to 50,
- j is a number from 0 to 10,
- k is a number from 0 to 10, or
- (d)
- correspond to the radical R1,
- with the priviso that in the average molecule at least one radical R2 has the definition (a),
- a is a number from 1 to 500,
- b is a number from 0 to 10, and
- wherein the organopolysiloxane forms a clear solution in water in an amount not more that 20 g/l at 25° C.
- water, and optionally an auxiliary or additive.
Dependencies are inferred from the claim text.