Paper quality improver composition for papermaking

• US 20020117278A1
• Filed: 12/19/2000
• Published: 08/29/2002
• Est. Priority Date: 12/24/1999
• Status: Active Grant

• Current Assignee: KAO Corporation
• Original Assignee: KAO Corporation
• Inventors: Ikeda, Yasushi, Takahashi, Hiromichi, Tadokoro, Takaaki
• Granted Patent: US 6,565,708 B2
• Time in Patent Office: Days
• US Class Current: 162/158
• CPC Class Codes: D21H 17/06 Alcohols; Phenols; Ethers; Aldehydes; Ketones; Acetals; Ketals
• CPC Class Codes: D21H 17/07 Nitrogen-containing compounds
• CPC Class Codes: D21H 17/09 Sulfur-containing compounds
• CPC Class Codes: D21H 17/14 Carboxylic acids; Derivatives thereof
• CPC Class Codes: D21H 17/28 Starch
• CPC Class Codes: D21H 17/29 cationic
• CPC Class Codes: D21H 17/36 Polyalkenyalcohols; Polyalkenylethers; Polyalkenylesters
• CPC Class Codes: D21H 17/375 Poly(meth)acrylamide
• CPC Class Codes: D21H 17/59 obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon
• CPC Class Codes: D21H 17/60 Waxes
• CPC Class Codes: D21H 21/14 characterised by function or properties in or on the paper D21H19/66, D21H27/02 take precedence
• CPC Class Codes: D21H 21/22 Agents rendering paper porous, absorbent or bulky
• CPC Class Codes: D21H 21/24 Surfactants

Abstract

The present invention provides a paper quality improver composition for papermaking, which is excellent in improved efficiencies of bulky value, brightness, opacity and the like of pulp sheet, demanded at lightening paper and increasing a blending amount of deinked pulp, even by adding a small amount thereof as well as which is further excellent in an improved efficiency of paper-strength. That is, the present invention provides a paper quality improver composition for papermaking; which comprises (A) a compound having lyotropic degree measured by a specific method of not less than 4% and satisfying at least two of (i) standard improved bulky value of not less than 0.02 g/cm³, (ii) standard improved brightness of not less than 0.5 point, and (iii) standard improved opacity of not less than 0.5 point and (B) a water-soluble polymer satisfying an average molecular weight and/or a viscosity thereof of specific value.

Claims

1. A paper quality improver composition for papermaking;

which comprises (A) a compound having a lyotropic degree, defined below, of not less than 4% and meeting at least two efficiencies selected from the following paper quality improving efficiencies (i) to (iii) and (B) a water-soluble polymer satisfying at least one selected from an average molecular weight of 1000 to 10000000 and a viscosity of 1 to 4000 mPa•

s at 25°

C. in a 1% aqueous solution thereof;

which is internally added before or in papermaking step;

(i) standard improved bulky value of not less than 0.02 g/cm³, (ii) standard improved brightness of not less than 0.5 point, and

(iii) standard improved opacity of not less than 0.5 point; and

lyotropic degree (%)=(α

₀−

α

)/α

₀×

100

wherein α

;

the water content in a wet sheet obtained by adding 5 parts by weight of the compound which becomes the paper quality improver composition for the papermaking to 100 parts by weight of pulp and subjecting the resultant to the papermaking, and α

₀;

the water content in a wet sheet obtained by subjecting pulp to the papermaking without adding the compound which becomes the paper quality improver composition for papermaking to the pulp.

2. The composition as claimed in claim 1, which contains at least one surfactant (C).

3. The composition as claimed in claim 1 or 2, wherein the compound (A) is selected from the group consisting of (A1) organosiloxane, (A2 ) glyceryl ether, (A3 ) amide, (A4 ) amine, (A5) an acid salt of amine, (A6 ) a quaternary ammonium salt, (A7) an imidazol compound, (A8 ) an ester of a polyhydric alcohol and a fatty acid, and (A9 ) an alkylene oxide-added ester being an ester derived from a polyhydric alcohol and a fatty acid and having from more than zero mole to less than 12 moles on the average of C_2-4 alkylene oxide group per 1 mole of the ester.

4. The composition as claimed in claim 1 or 2, wherein the compound (A) is (A8 ) an ester of polyhydric alcohol and a fatty acid.

5. The composition as claimed in claim 1 or 2, wherein the compound (A) is (A8) being composed from a 3- to 6-hydric alcohol and a fatty acid having 10 to 22 carbon atoms in total.

6. The composition as claimed in claim 1 or 2, wherein the water-soluble polymer (B) is selected from the group consisting of (B-1) a polyacrylamide-based polymer(s), (B-2) a polyvinylalcohol-based polymer(s), (B-3) a starch(s) and/or denatured starch(s) and (B-4) a gum oleoresin(s).

7. The composition as claimed in claim 1 or 2, wherein the water-soluble polymer (B) is selected from the group consisting of (B3-1) a corn starch, (B3-2) a potato starch, (B3-3) a wheat starch, (B3-4) a tapioca starch, (B3-5) an oxidized starch and (B3-6) a cationic starch.

8. The composition as claimed in claim 2, wherein the surfactant (C) is selected from the group consisting of (C1) a salt of a higher fatty acid, (C2) a salt of a sulfate of a higher alcohol, (C3) a salt of an alkylbenezene sulfonic acid, (B4) a salt of a sulfosuccinic acid diester, (C5) a condensate of naphthalene sulfonic salt with formaldehyde, (C6) a salt of a polycarbonic acid and (C7) a quaternary ammonium salt.

9. A process for producing a pulp sheet, which comprises adding the composition as defined in claim 1 or 2 anytime before or in the papermaking step.

10. A pulp sheet produced by adding the composition as defined in claim 1 or 2 anytime before or in the papermaking step.

11. The process as claimed in claim 9, in which the composition is internally added.

12. The composition as claimed in claimed in claim 1, in which (B) the water-soluble polymer is (B3-6) a cationic starch.