Patent EP0451842A1 successfully refreshed from Google Patents.
EP0451842A1
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EP
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Pretreatment of filler with cationic ketene dimer
Assignee: Hercules LLC
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Filing: 1991-04-11
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Granted: —
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Expires: 2011-04-11
Abstract
Abstract A filler for paper or paperboard comprising an inorganic pigment and a cellulose-reactive size, a process for preparing the filler in which the inorganic pigment dispersed in water is treated with a dispersion of the cellulose-reactive size before the filler is added to the dispersion of cellulose fibers in a paper machine, and the use of the treated filler in a process for the manufacture of paper and paperboard in order to maintain the capability of the cellulose fiber and filler mixture to receive sizing independently of the level of filler addition.
Inventors
- 👤 David Howard Dumas
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 05:18
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/03; D21H17/05; D21H17/17; D21H17/07; D21H17/08; D21H17/14; D21H17/15; D21H17/16; D21H17/63; D21H17/67; D21H17/69; D21H21/00; D21H21/14; D21H21/16
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
59 words
A filler for paper or paperboard comprising an inorganic pigment, characterized in that it consists essentially of from about 97 to about 99.9% by weight of the inorganic pigment, from about 0.025 to about 2.7% by weight of a cellulose-reactive size selected from the group consisting of ketene dimers, alKenyl succinic anhydrides, hydrophobic isocyanates, carbamoyl chlorides, and stearic anhydrides.
Claim 2
Dependent Claim
35 words
A filler as claimed in claim 1, further characterized in that it contains 0.00625 to about 2.7% by weight of a dispersing agent composition comprising at least 95% by weight of a cationic dispersing agent.
Claim 3
Dependent Claim
35 words
A filler as claimed in claim 1 or 2, further characterized in that the inorganic pigment comprises particulate material selected from the group consisting of calcium carbonate, clay, titanium dioxide, talc and hydrated silica clay.
Claim 4
Dependent Claim
18 words
A filler as claimed in claim 3, further characterized in that the inorganic pigment comprises precipitated calcium carbonate.
Claim 5
Dependent Claim
58 words
A filler as claimed in any one of the preceding claims, further characterized in that the cellulose-reactive size is a ketene dimer having the general formula: in which R₁ and R₂ are hydrocarbon groups having from 8 to 30 carbon atoms, or an alkenyl succinic anhydride in which the alkenyl group has from 12 to 30 carbon atoms.
Claim 6
Dependent Claim
36 words
A filler as claimed in claim 5, further characterized in that the cellulose-reactive size is a ketene dimer in which the R₁ and R₂ groups are saturated hydrocarbon groups having from 14 to 16 carbon atoms.
Claim 7
Dependent Claim
33 words
A filler as claimed in any one of the preceding claims, further characterized in that the reactive cellulose size is present in an amount of from about 0.1 to about 1.8% by weight.
Claim 8
Dependent Claim
39 words
A filler as claimed in any one of the preceding claims, further characterized in that the cationic dispersing/agents are selected from the group consisting of naturally occurring cationic polymers, synthetically produced cationic polymers, or a combination of both types.
Claim 9
Dependent Claim
38 words
A filler as claimed in claim 8, further characterized in that the cationic dispersing agent is a cationic starch, a cationic gum, a cationic polyamine, a cationic polyamide, a cationic polyurylene, or a mixture of any of them.
Claim 10
Dependent Claim
36 words
A filler as claimed in claim 9, further characterized in that the cationic dispersing agent is a combination of a cationic polyamide and a cationic starch in a weight ratio of at least 2 to 1.
Claim 11
Dependent Claim
33 words
A filler as claimed in any one of the preceding claims, further characterized in that the cationic dispersing agent is present in an amount of from about 0.025 to about 1.8% by weight.
Claim 12
Dependent Claim
119 words
A process for preparing a filler as claimed in any one of the preceding claims for paper or paperboard, comprising dispersing an inorganic pigment in water before adding it to a paper machine, characterized in that from about 25 to about 75% by weight on a dry basis of a cellulose-reactive size is dispersed in water with about 20 to 90% by weight on a dry basis of a cationic dispersing agent to form a treatment dispersion, and particles of the inorganic pigment are contacted with the dispersion in the proportion of 0.1 to 2.0 parts by weight of the sizing solids in the dispersion on a dry basis for each 100 parts by weight of the inorganic particles.
Claim 13
Dependent Claim
53 words
A process as claimed in claim 12, further characterized in that and particles of the inorganic pigment are contacted with the dispersion in the proportion of 0.3 to 1.0 parts by weight of the sizing solids in the dispersion on a dry basis for each 100 parts by weight of the inorganic particles.
Claim 14
Dependent Claim
99 words
A process as claimed in claim 12 or 13 , further characterized in that the cationic dispersing agent is a naturally-occurring cationic polymer in an amount of from 10 to 35% by weight of the dispersion, or a synthetic cationic polymer in an amount of from 10 to 75% by weight of the dispersion, or a combination of both types in a total amount of at least 10%, with the natural polymer being from about 9 to 20% by weight and the synthetic polymer being up to about 70% by weight of the dispersion, all on a dry basis.
Claim 15
Dependent Claim
62 words
Use of the filler claimed in any one of claims 1 to 11 in a process for the manufacture of paper and paperboard, in which a wet laid cellulosic sheet is formed by dewatering a dispersion of cellulosic fibers and then dried to form the paper or paperboard product, by adding a dispersion of the filler to the dispersion of cellulose fibers.
References Cited (Backward Citations)
US2865743A
Cited
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