Claims
- 1. Paper or paperboard prepared by a method comprising the steps of:
- (a) providing a paper stock system;
- (b) forming in the absence of high shearing forces and under normal pressures, a sizing emulsion consisting essentially of water and 0.1 to 15% by weight of at least one hydrophobic sizing agent selected from the group consisting of alkyl ketene dimers, anhydrides of fatty acids, maleated triglycerides, maleated alpha-olefins, maleated fatty acids and substituted linear or cyclic dicarboxylic acid anhydrides and 0.4 to 30% by weight of a jet cooked dispersion of a hydrophobic starch ether or ester derivative wherein the ether or ester substituent comprises a saturated or unsaturated hydrocarbon chain of at least 5 carbon atoms in the alkyl chain or a dispersion of a corresponding derivative gum;
- (c) forming a web from the paper stock system;
- (d) dispersing said emulsion within the paper stock either before or after formation of said web but prior to passing said web through the drying stage of the paper making operation in an amount sufficient to provide a concentration of the sizing agent of from 0.01% to 2%, based on dry fiber weight.
- 2. The paper or paperboard of claim 1 wherein the size emulsion contains a jet cooked dispersion of a derivative of starch.
- 3. A method for sizing paper products comprising the steps of:
- (a) providing a paper stock system;
- (b) forming in the absence of high shearing forces and under normal pressures, a sizing emulsion consisting essentially of water and 0.1 to 15% by weight of at least one hydrophobic sizing agent selected from the group consisting of alkyl ketene dimers, anhydrides of fatty acids, maleated triglycerides, maleated alphaolefins, maleated fatty acids and substituted linear or cyclic cicarboxylic acid anhydrides and 0.4 to 30% by weight of a jet cooked dispersion of a hydrophobic starch ether or ester derivative wherein the ether or ester substituent comprises a saturated or unsaturated hydrocarbon chain of at least 5 carbon atoms in the alkyl chain or a dispersion of a corresponding derivative gum;
- (c) forming a web from the paper stock system;
- (d) dispersing said emulsion within the paper stock either before or after formation of said web but prior to passing said web through the drying stage of the paper making operation in an amount sufficient to provide a concentration of the sizing agent of from 0.01% to 2%, based on dry fiber weight.
- 4. The method of claim 3 wherein the size emulsion contains a jet cooked dispersion of a derivatives of starch.
- 5. Paper or paperboard prepared by the method of claim 4.
- 6. The method of claim 3 wherein there is additionally added a cationic retention agent in an amount sufficient to provide 0.01 to 3% by weight of the retention agent on the dry fiber weight.
- 7. The method of claim 3 wherein the hydrophobic sizing agent is a substituted linear or cyclic dicarboxylic acid anhydride.
- 8. The method of claim 3 wherein the hydrophobic sizing agent is represented by the following formula: ##STR10## wherein R represents a dimethylene or trimethylene radical and wherein R' is a hydrophobic group containing more than 4 carbon atoms which may be selected from the class consisting of alkyl, alkenyl, aralkyl or aralkenyl groups.
- 9. The method of claim 3 wherein the hydrophobic sizing agent is an alkenyl succinic acid anhydride.
- 10. The method of claim 3 wherein the hydrophobic sizing agent is a higher organic ketene dimer of the following formula: ##STR11## wherein R and R' are independently chosen from the group consisting of saturated and unsaturated alkyl radicals having at least eight carbon atoms, cycloalkyl radicals having at least six carbon atoms, aryl, aralkyl and alkaryl radicals.
- 11. The method of claim 3 wherein the starch or gum derivative is prepared by treating the starch of gum with at least 1% by weight of the polysaccharide of the long chain alkyl derivatizing reagent.
- 12. The method of claim 11 wherein the starch or gum derivative is prepared by treating the starch or gum with 3-20% by weight of the starch of the derivatizing reagent.
- 13. The method of claim 11 wherein the starch or gum derivative is prepared by treating the starch or gum with 3-10% by weight of the derivatizing reagent.
- 14. A method for sizing paper products comprising the steps of:
- (a) providing a paper stock system;
- (b) forming in the absence of high shearing forces and under normal pressures, a sizing emulsion consisting essentially of water and 0.1 to 15% by weight of at least one hydrophobic sizing agent selected from the group consisting of alkyl ketene dimers, anhydrides of fatty acids, maleated triglycerides, maleated alpha-olefins, maleated fatty acids and substituted linear or cyclic dicarboxylic acid anhydrides and 0.4 to 30% by weight of a jet cooked dispersion of a hydrophobic starch ether or ester derivative wherein the ether or ester substituent comprises a unsaturated hydrocarbon chain of at least 5 carbon atoms in the alkyl chain;
- (c) forming a web from the paper stock system;
- (d) dispersing said emulsion within the paper stock either before or after formation of said web but prior to passing said web through the drying stage of the paper making operation in an amount sufficient to provide a concentration of the sizing agent of from 0.01% to 2%, based on dry fiber weight.
- 15. The method of claim 14 wherein the derivative of starch is a cationic ether, succinate ester or fatty acid ester.
- 16. The method of claim 14 wherein the starch is selected from the group consisting of corn, waxy maize, potato, tapioca, and high amylose corn.
- 17. The method of claim 14, wherein the starch derivative is an ester prepared from a substituted cyclic dicarboxylic acid anhydride having the structure ##STR12## wherein R is a dimethylene or trimethylene radical and A' comprises a hydrocarbon chain of at least 5 carbon atoms.
- 18. The method of claim 17 wherein the starch derivative is prepared from an alkenyl succinic acid anhydride.
- 19. The method of claim 14 wherein the starch derivative is prepared from the imidazolides or N,N'-disubstituted imidazolium salts of carboxylic or sulfonic acids having the general formula ##STR13## wherein Z is ##STR14## or --SO.sub.2 --, A comprises a hydrocarbon chain of at least 5, carbon atoms, R.sup.1 is H or C.sub.1 -C.sub.4 alkyl, R.sup.2 is C.sub.1 -C.sub.4 alkyl, and X.sup.- is an anion.
- 20. The method of claim 14 wherein the starch derivative is prepared from the reaction product of an epihalohydrin with a tertiary amine having the structure ##STR15## wherein R.sup.3 and R.sup.4 are independently H or a C.sub.1 -C.sub.4 alkyl and A.sup.2 comprises a hydrocarbon chain of at least 5 carbon atoms.
Parent Case Info
This application is a division, of application Ser. No. 811,869, filed Dec. 20, 1985, now U.S. Pat. No. 4,687,519.
US Referenced Citations (11)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1069410 |
Jan 1980 |
CAX |
0014520 |
Jun 1980 |
EPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
811869 |
Dec 1985 |
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