Abstract: Sizing dispersions of liquid reactive size are made by dispersing the reactive size as a neat liquid into a dispersion of bentonite or other anionic microparticulate material in water. These dispersions can be used for internal sizing, for instance wherein the dispersion is used as the anionic microparticulate stage in a microparticulate retention paper-making process, or they can be used for external sizing.
Type:
Grant
Filed:
August 21, 1998
Date of Patent:
September 4, 2001
Assignee:
Ciba Specialty Chemicals Water Treatments Limited
Inventors:
Peter Peutherer, Ian Mark Waring, Lesley Collett
Abstract: A drainage/retention aid comprising a combination of
a) microparticles; and
b) a vinylamine copolymer having the general structure:
wherein m is from 1-99 mol %, n is from 0 to 50 mol % and o is from 1 to 99 mol %; A is selected from the group consisting of one or more repeating units having the following general structures:
and salts thereof wherein p, q and r are mol percentages from 1 to 99, each R1 is independently H or CH3, and
X is —CN, —COOR2, —CONR3R4, —OR5, —OCOR6,
and mixtures thereof; wherein R2, R3, R4, R5, R6 are independently selected from H or C1 to C4 alkyl; and
wherein the vinylamine copolymer has a charge density in a range of from 2 to 24 mEq/g.
Type:
Grant
Filed:
August 16, 1994
Date of Patent:
August 14, 2001
Assignee:
Betzdearborn Inc.
Inventors:
Lawrence Lu Kuo, Roger Yiming Leung, Steven R. Prescott, Thord Hassler
Abstract: The invention comprises a borosilicate retention aid composition and a method for improving the production of paper by addition of the borosilicate. The borosilicate may be utilized in conjunction with a high molecular weight synthetic flocculant and/or starch, with or without the addition of a cationic coagulant. The borosilicate material is preferably a colloidal borosilicate. Methods for the preparation of the borosilicate material are disclosed.
Abstract: The present invention relates to a process for easily and efficiently producing silica particles having a narrow particle size distribution and a high porosity from inexpensive starting materials such as sodium silicate. The silica particles of the present invention can be obtained in the form of a slurry containing them by (1) forming a slurry by mixing first particles difficultly soluble in an alkali and soluble in an acid, with an aqueous alkali silicate solution to form a first slurry containing the first particles, (2) neutralizing the first slurry with a mineral acid to prepare a second slurry containing second particles wherein silica is deposited on the first particles, and (3) adding a mineral acid to the second slurry to dissolve the first particles from the second particles, to prepare a third slurry containing silica particles.
Abstract: The invention relates to an aqueous silica-based sol comprising a nitrogen-containing organic compound and silica-based particles with a specific surface area of at least 300 square meters per gram of silica. The invention further relates to a process for the production of an aqueous silica-based sol comprising a nitrogen-containing organic compound which comprises incorporating a nitrogen-containing organic compound into a silica-based sol containing silica-based particles with a specific surface area of at least 300 square meters per gram of silica. The invention also relates to the use of an aqueous silica-based sol comprising a nitrogen-containing organic compound and silica-based particles with a specific surface area of at least 300 square meters per gram of silica as a flocculating agent in the production of pulp and paper and in water purification.
Type:
Application
Filed:
December 19, 2000
Publication date:
June 28, 2001
Inventors:
Peter Greenwood, Magnus Olof Linsten, Hans E. Johansson-Vestin
Abstract: Starch is added to the thinstock in a papermaking process in the form of a coagulated slurry containing undissolved starch particles, cationic polymeric flocculant and anionic microparticulate network agglomeration aid, such as bentonite. The flocculant and agglomeration aid interact to give network flocculation in which the starch particles are trapped. Improved retention of the starch in the resulting paper is achieved.
Type:
Grant
Filed:
May 10, 1999
Date of Patent:
May 29, 2001
Assignee:
Ciba Specialty Chemicals Water Treatments Limited
Abstract: A papermaking process consisting essentially of:
forming an aqueous cellulosic papermaking slurry;
adding to the slurry certain additives, with said certain additives selected from the group including: coagulants; sizing agents; and mineral fillers;
draining the slurry to form a sheet; and
drying the sheet to form a paper sheet;
the improvement comprising adding to the slurry, prior to it being drained; an effective amount of a cationic dispersion polymer; which cationic dispersion polymer is a copolymer comprising about 30 mole % diallyldimethylammonium chloride (DADMAC) and about 70 mole % acrylamide (AcAm); and
adding to the slurry, either before or after said cationic dispersion polymer is added and the slurry is drained,
a microparticle selected from the group consisting of
a) copolymers of acrylic acid and acrylamide;
b) bentonite; and
c) dispersed silica;
with the proviso that said coagulant cannot be a cationic dispersion copolymer comprising about 30 mole % diallyldimethylammonium chloride
Type:
Grant
Filed:
May 21, 1999
Date of Patent:
May 29, 2001
Assignee:
Nalco Chemical Company
Inventors:
Jane B. Wong Shing, Chidambaram Maltesh, Ramasubramanyam Nagarajan
Abstract: Synthetic polymers having hydrogen bonding capability and one or more polysiloxane moieties are capable of providing two distinct properties to paper products, such as tissues, which properties heretofore have been imparted through the use of at least two different molecules. The backbone of these synthetic polymers is based on modified vinyl polymers, such as polyvinyl alcohol, polyacrylamides and polyacrylic acids.
Type:
Grant
Filed:
November 24, 1999
Date of Patent:
May 1, 2001
Assignee:
Kimberly-Clark Worldwide, Inc.
Inventors:
Wen Zyo Schroeder, Daniel Arthur Clarahan, Mike Thomas Goulet, Thomas Gerard Shannon
Abstract: An aqueous aluminium silicate suspension having a content of aluminium silicate of at least 30 wt. % is prepared by liquefaction of the aluminium silicate filter cake or by dispersion of aluminium silicate powder in water with the addition of aluminium silicate powder, surfactant and aluminium sulfate. It can be employed in papermaking.
Abstract: Anionic nanocomposites for use as retention and drainage aids in papermaking are prepared by adding an anionic polyelectrolyte to a sodium silicate solution and then combining the sodium silicate and polyelectrolyte solution with silicic acid.
Abstract: A microparticle composition for paper making includes finely divided particles of a water insoluble solid such as amorphous sodium aluminosilicate, and having an anionic charge of at least 20 millivolts, and preferably from about 40 to 60 millivolts, and a particle size of less than about 0.1 microns.
Abstract: A method of coagulating particulates, as in papermaking or water clarification applications, for example, is provided wherein a zeolite crystalloid coagulant is added to water containing the solid matter, a source of multivalent cations, and a cationic acrylamide polymer. The zeolite crystalloid coagulant is preferably prepared by admixing aqueous sodium silicate and sodium aluminate solutions to form a reaction mixture and allowing a reaction to proceed for a sufficient time to form a zeolite crystalloid coagulant particles having particle sizes of at least about 4 nm before terminating the reaction.