JP2002520505A - Fine particle system in papermaking process - Google Patents

Abstract

  (57) [Summary] Retention and drainage aids, including particulate systems used in the manufacture of alkaline and acidic paper products, include inorganic particulate materials comprising a flocculant polymer and an aluminum substituted trioctahedral mineral, and optionally a cationic coagulant. The polymeric flocculant is added to the furnish before the fan pump and after the press screen. The inorganic particulate material is added to the furnish after the press screen, and optionally the coagulant is added before the fan pump.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to an improved microparticulate system and to the manufacture of paper products, ie paper and paperboard having improved properties in terms of retention, drainage and sheet formation. Using an improved microparticulate system as an auxiliary to the process.

[0002] In the production of paper or paperboard, a dilute aqueous composition called "furnish" or "stock" is sprayed onto a moving wire mesh called "wire". Solid components of the composition, such as cellulose fibers and inorganic particulate fillers, are drained or filtered by a wire to form a paper sheet. The percentage of solid material retained on the wire is known as the "first pass retention" in the papermaking process.

[0003] Retention is believed to be a function of different mechanisms, such as filtration by mechanical entrainment, electrostatic attraction, and crosslinking between fibers and fillers in the furnish. Because cellulosic fibers and many conventional fillers are negatively charged, they repel each other. Generally, the only factor that seeks to increase retention is mechanical entrainment. Accordingly, retention aids are commonly used to improve retention of fibers and fillers on the wire.

[0004] Drainage is related to the rate at which water is removed from the furnish in forming the paper sheet. Drainage usually refers only to the removal of water that occurs prior to the compaction of the paper sheet following sheet formation. Thus, drainage aids are used to improve the overall efficiency of dewatering in paper or paperboard production.

[0005] Formation relates to the formation of paper or paperboard produced in the papermaking process.
Formation is generally evaluated by dispersion of light transmittance in a paper sheet. A high variance indicates a bad formation and a low variance indicates a low variance.
Good. " In general, as the retention level increases, the level of formation decreases from good formation to bad formation.

[0006] It is understood that improving the retention and drainage of paper or paperboard final products, as well as the formability, is particularly desirable for a number of reasons, the most important of which is productivity. If the retention and drainage are good, the papermaking apparatus can be operated faster and the number of stoppages can be reduced. Good sheet formation improves the paper yield. These improvements are achieved through the use of retention and drainage aids.
Retention and drainage aids are used to agglomerate the fine solids present in the furnish and improve these parameters in the papermaking process. The use of such additives is limited by the agglomeration effect on paper sheet formation. The addition of more retention aid increases the size of the fine solids, which changes the density of the paper sheet, and thus results in a so-called "bad" sheet formation, as described above. Excessive agglomeration also affects drainage because it causes perforations in the sheet and creates a reduced pressure loss in the subsequent dewatering step of the papermaking process. Retention and drainage aids added to the furnish at the wet end of the papermaking equipment are generally of three types: (a) single polymers (b) two polymers (c) flocculants and / or Or Particulate Systems Used With Coagulants Particulate systems generally give the best results as retention and drainage aids and are widely described in the prior art. Examples of particulate-based literature include: EP-B-235,893 where bentonite in combination with a high molecular weight cationic polymer in a particular order of addition is used as inorganic material; silica, bentonite, China clay, etc. WO-A-94 / 26972 describing vinylamide polymers in combination with one of a variety of inorganic materials and organic materials; WO-A-94 / 26972 describing kaolin used in combination with one of a variety of cationic polymers -A-97 / 16598; and EPO 805234 wherein bentonite, silica or acrylate polymers are used in combination with a cationic dispersion polymer.

Another particulate system containing bentonite as an inorganic material is disclosed in US Pat. No. 4,749,4.
44, 4,753,710, 4,913,775, 4,969,97
No. 6, No. 5,126,014, No. 5,234,548, No. 5,393,38
No. 5,415,740, 5,514,249 and 5,532
No. 308. Some of these particulate systems utilize a coagulant and / or coagulant added to the wet end of the papermaking equipment in addition to a particular order of addition of inorganic materials.

[0008] A particulate system comprising a swellable smectite clay for use with an anionic polymer dispersant is disclosed in US Pat. No. 5,015,334. US Patent 5,
No. 071,512 discloses a particulate system using hectorite in combination with a cationic starch. U.S. Pat. No. 5,178,730 discloses a hectorite particulate system used in combination with a medium or high molecular weight cationic polymer. U.S. Pat. No. 5,194,120 discloses the use of synthetic amorphous magnesium silicate, such as laponite, in combination with a medium or high molecular weight cationic polymer. These components of some particulate systems are subjected to one or more shearing steps, such as cleaning, mixing and pumping steps, such as centrifugal screens, vortex cleaners, fan pumps, and mixing pumps. It is added to the wet end of the papermaking equipment in a particular order of addition.

[0009] Some of these prior art particulate systems mentioned above generally use "bentonite" as an inorganic material. However, the term "bentonite" is used vaguely and is not generally considered to include saponite, which is described in more detail below.

[0010] Particulate systems generally include a cationic coagulant and a polymeric flocculant with or without fine inorganic particulate matter. Inorganic materials can improve the efficiency of the flocculant and / or produce smaller, more uniform flocs.

[0011] Currently in paper mills to achieve better runnability of papermaking equipment and / or to obtain specific end-use paper qualities, such as improved sheet formation for better printability, or improved surface strength. Although there are several particulate systems used, there is a very real and substantial need for particulate systems to improve paper or paperboard by improving drainage, retention and formation during the papermaking process. Still remains.

(Summary of the Invention) The present invention meets the above needs. The present invention relates to particulate systems used as retention and drainage aids in papermaking processes.

A first aspect of the present invention is a papermaking process wherein a particulate system as a retention and / or drainage aid comprising a high molecular weight coagulant and an inorganic particulate material is added to a paper stock or furnish, Inorganic particulate materials include aluminum-substituted trioctahedral minerals, such as saponite.

A second aspect of the present invention is an improved microparticle composition that can be added to a paper material or furnish as a retention and / or drainage aid, wherein the microparticle composition comprises a high molecular weight polymer aggregate. Agent and an inorganic particulate material, wherein the inorganic particulate material includes an aluminum-substituted trioctahedral mineral such as saponite.

[0015] A third aspect of the present invention is a paper or paperboard product having improved retention, drainage and formation properties, wherein the paper or paperboard product comprises an improved particulate system comprising an aqueous cellulosic raw material or finished paper. Produced by addition to the stock, the particulate system includes a high molecular weight flocculant and inorganic materials including aluminum substituted trioctahedral minerals such as saponite.

A fourth aspect of the present invention includes the step of producing a paper or paperboard product from an aqueous cellulose furnish, comprising the steps of: (a) adding a high molecular weight polymer flocculant after the first shearing step to the finished paper; Adding an inorganic particulate material, including aluminum-substituted trioctahedral minerals, such as saponite, to the dilute solution stream of the furnish raw material after the second shearing step; b) draining the furnish to form a sheet; and (c) drying the sheet.

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a particulate system as a retention and / or drainage aid that is particularly used at the wet end of papermaking equipment in the papermaking process for acidic and alkaline woodfree papers. .

As used herein, the term “paper” includes products that include cellulosic sheet materials, including paper sheets, paperboard, and the like.

The term “particulate system or composition” as used herein refers to a combination of at least one hydrophilic polymer and at least one inorganic particulate material. The components of this combination may be added to the raw material or furnish to be co-processed, but are preferably added separately in the method and sequence described below.

The present invention can be implemented using a conventional papermaking device. According to conventional methods, the furnish or "dilute stock" flowed to form the paper sheet typically contains dyes or fillers, suitable fibers, any desired reinforcement in a mixing vessel or mixing box. It is often prepared by diluting a concentrated stock solution prepared by blending an agent and / or other additives, and water (which may be recovered water). The dilute stock solution is purified by a usual method such as using a vortex cleaner. Typically, dilute stock solutions are purified by passing through a centrifugal screen. The dilute stock solution is usually sent along the papermaking machine by one or more centrifugal pumps known as fan pumps. For example, the diluted stock solution is sent to the centrifugal screen by the first fan pump. Before the suction point of the first fan pump or before the first fan pump, for example, a concentrated stock solution and dilution water may be passed through a mixing pump to dilute the concentrated stock solution with water to generate a diluted stock solution. . The diluted stock solution is further purified through a second centrifugal screen or a pressurized screen, and is passed through a head box before the sheet forming step of the papermaking apparatus.

The sheet forming step is performed using any conventional paper or paperboard forming apparatus, such as a flat wire fourdrinier, twin wire forming machine, or vat dye forming machine, or any combination of these forming apparatuses. Can be. A system for approaching a papermaking machine may include the components shown in FIG. These parts include a fan pump 1, a pressurizing screen 2, and a headbox 3. By passing the concentrated undiluted solution and dilution water through a mixing pump (not shown), the concentrated undiluted solution is diluted with water into the diluted undiluted solution before entering the fan pump 1. Contaminants are removed by passing the dilute stock solution through the press screen 2, and the dilute stock solution coming out of the press screen 2 is guided to the head box 3 before sheet formation.

FIG. 1 also illustrates preferred points of addition of the components of the particulate system of the present invention. Preferably, when using a cationic coagulant, the cationic coagulant is added before the dilute stock solution passes through the fan pump 1, the movement of which is indicated by arrow 4 and the addition is indicated by arrow 5. The coagulant is added when the dilute stock solution exits the fan pump 1, as indicated by the arrow 6, and the inorganic particulate material is added when the dilute stock solution exits the press screen 2, as indicated by the arrow 7. . The fan pump 1 and the pressure screen 2 form a high-shear process in the papermaking apparatus.

In the present invention, it is preferred that the particulate high molecular weight flocculant polymer is added before the dilute stock solution reaches the final point of high shear, so that the dilute stock solution is, for example, a particulate inorganic particulate material Is preferably sheared at the last point of high shear before adding. As shown in FIG. 1, the flocculant is added before the dilute stock solution passes through the press screen 2, and the microparticles are added after the stock solution passes through the press screen 2.

The fine particle type flocculant of the present invention is preferably added to a dilute stock solution (that is, a solid content of preferably 2% by weight or less, at most 3% by weight) rather than a concentrated stock solution. Thus, the flocculant is added directly to the diluted stock solution or to the dilution water used to convert the concentrated stock solution to a diluted stock solution.

High molecular weight flocculant polymers include agents for flocculating solids, especially fine solids, in papermaking stock. As used herein, the term "micro" refers to TAP
Mean fine solid particles and fibers as defined in PI Test Methods T261 and T269.

Agglomeration of the fine solids of the furnish occurs in the high molecular weight polymer itself, or in the high molecular weight polymer in combination with other agents, such as a high charge density cationic coagulant. The fine solids are better retained in the fiber structure of the paper sheet formed by the aggregation of the fine solids, and dewatering or drainage is improved.

The high molecular weight polymer flocculant is preferably a polymer that itself has a flocculating action.

Examples of high molecular weight flocculant polymers suitable for use in the present invention include those having an average molecular weight of about 100
000 or more, especially 500,000 or more. Preferably, the molecular weight is at least about 1 million, often at least about 5 million, for example in the range of 10 to 30 million. These polymers are linear or branched, cationic, anionic, nonionic or amphoteric, or hydrophobically modified acrylamide or other nonionic polymers.

In the present invention, the amount of the high molecular weight polymer flocculant of the fine particle system added to the stock solution or the furnish has a substantial effect of agglomerating solids, especially fine solids present in the stock solution or the furnish. Any amount is enough to give. The total amount of water-soluble polymer added is from about 0.0025% to 1.0% by weight, more preferably about 0.01% by weight.
%, Most preferably from about 0.025% to 0.1% by weight (dry weight of polymer relative to dry weight of solids present in the stock or furnish). It is preferred that the addition be made in one or more addition locations in one or more additions and be added in a single addition to the dilute stock stream after the fan pump that produces high shear.

The coagulated mass purified with the high molecular weight polymer flocculant is desirably subjected to a shearing action before the addition of the particulate inorganic particulate material. This shearing action is preferably induced by a pressure screen that produces a high shearing action.

The amount of particulate inorganic particulate material added to the stock solution or furnish in the process of the present invention is from about 0.005 to about 2.0% by weight, preferably from about 0.05 to about 0. 5% by weight
(Based on the dry weight of solids present). The addition is performed once or more at one or more addition sites, but is preferably performed once, and is performed at least between the pressure screen 2 and the head box 3 after the pressure screen 2 in FIG. Is preferred.

The particulate inorganic material of the present invention is preferably saponite which is an aluminum-substituted trioctahedral mineral.

The patent literature on retention, drainage and sheet formation describes a variety of clay minerals, broadly referred to as “bentonite” or “swellable clay” or simply “fines”. Clay mineralogy is a complex field, and as mentioned above, terms are often used vaguely. No. 5,178,7 mentioned above.
No. 30 discusses this content at column 4, lines 14-32, and includes the following: "For example, in U.S. Pat. No. 4,753,710, bentonite and bentonite-type clays are sepiolite, attapulgite, or preferably Is described as being an anionic swelling clay such as montmorillonite, which also refers to the broader description of bentonite in US Patent No. 4,305,781 (commercially available bentonite, montmorillonite clay, U.S. Pat. No. 4,749,444 discloses bentonite containing nontronite, hectorite, saponite, forconscoite, sauconite, beidellite, arebanite, illite, halloysite, atapulgite, and sepiolite. Swelling It is generally accepted in current clay mineralogy texts that many of these minerals are not normally found in bentonite and should not be classified. For example, some of them are not smectite groups (arevalite, illite, halloysite, attapulgite and sepiolite) and few are swellable (illite, atapulgite and sepiolite). "US Pat. No. 5,178,730. In the issue, true "bentonite" is a "2 octahedral" smectite, and true "hectorite" contains clay of its natural origin.
It is said to be "3 octahedral" smectite.

The smectite family of clay minerals is generally a three-layer mineral comprising an octahedral central layer of alumina or magnesia sandwiched between two layers of silica tetrahedron. If the central octahedral layer contains aluminum ions, the smectite clay is called a "2 octahedral" mineral. If the central octahedral layer contains magnesium ions, the smectite clay is called a "3 octahedral" mineral. Smectite minerals differentiate in their structure and chemical composition by so-called “isomorphous substitution”, with a certain percentage of silicon atoms in the outer tetrahedral layer and / or a certain percentage of aluminum or magnesium in the central octahedral layer. Are replaced with different atoms.

The “base mineral” of the dioctahedral subclass is a pyrophyllite that does not allow isomorphous substitution in either the tetrahedral or octahedral layers. As a result of having no interlayer cations or water, the pyrophyllite does not swell. Montmorillonite, forconscoite, beidellite and nontronite belong to this pyrophyllite subclass with different substitutions in the three layers.

For example, montmorillonite is characterized in that aluminum is replaced by magnesium in the octahedral layer (typically about 15 to 20% by atom number). In beiderite, a part of the silicon in the tetrahedral layer is replaced by aluminum. Bentonite (Wyoming Clay, Fuller's Earth) is a rock type that is primarily purified by weathering of montmorillonite and often volcanic ash, often containing a certain amount of beidellite.
In nontronite, aluminum is basically replaced by iron in the octahedral layer, and a certain amount of silicon is replaced by aluminum in the tetrahedral layer. Forconscoite is similar to nontronite, but contains more chromium than iron in the octahedral layer. Bentonite in most prior art documents is a smectic clay of this type and generally belongs to montmorillonite.

The “base mineral” of the trioctahedral subclass, which does not contain isomorphous substitutions in either the octahedral layer or the outer tetrahedral layer, is talc and does not exhibit swelling, as does pyrophyllite. Hectorite, saponite, sauconite, and sometimes vermiculite also belong to the trioctahedral subclass. Hectorite generally has a central octahedron layer in which part of the magnesium is replaced by lithium. In the saponite, part of magnesium is replaced by aluminum in the central octahedral layer, and part of silicon is replaced by aluminum in the outer octahedral layer. In sauconite, the dominant atom in the central octahedral layer is zinc rather than magnesium, with some of the zinc atoms replaced with aluminum and some of the silicon atoms in the outer tetrahedral layer with aluminum. Vermiculite is highly substituted for aluminum or iron for silicon and magnesium cations are between the layers, but most other naturally occurring smectites as described above have calcium or sodium cations between the layers. As used herein, “saponite” is a trioctahedral clay mineral in which aluminum has been substituted in the central octahedral layer and the outer tetrahedral layer.

It is preferred that saponite is the particulate inorganic material of the present invention. However, other aluminum substitutions such as sauconite and vermiculite 3
It should be understood that octahedral clay can also be used. These trioctahedral minerals are distinguished from prior art hectorites in that the hectorite contains lithium substituted in the central octahedral layer, and the montremilonite is replaced by magnesium in the central octahedral layer. It is distinguished from montremylonite, for example bentonite of the prior art, in that it is a dioctahedral mineral.

The addition of the high molecular weight flocculant polymer generally results in large agglomerates of suspended solids in the stock solution or furnish to which the polymer has been added. These large agglomerates are broken down, immediately or sequentially, by high shear forces into very small agglomerates known as "micro-agglomerates". This "high shear" is induced by passing the agglomerated furnish through the pressure screen 2 of FIG.

Still referring to FIG. 1, a water-soluble polymer, typically having a lower molecular weight than the flocculant, can be used as a coagulant by adding it to the concentrated stock solution, but before the stock solution passes through the fan pump 1. Is preferred. This coagulant is preferably a high charge density cationic polymer. For example, when the coagulant polymer is a cationic polymer containing nitrogen, the equivalent of nitrogen per kilogram of polymer is 0.2 equivalents or more, preferably at least 0.35 equivalents, and most preferably 0.4 to 2.5 equivalents. It is. When the polymer is formed by polymerization of a cationic ethylene-substituted monomer and optionally other monomers, the amount of cationic monomer is usually at least 2 mol%, usually at least 5 mol%, based on the total amount of monomers used to form the polymer. Mol% or more, preferably at least 10 mol% or more.

Suitable cationic coagulants include inorganic aluminum salts, polyaluminum chloride (P
AC), polydiallyldimethylammonium chloride (p-DADMAC); polyalkylamines; cationic polymers of epichlorohydrin with dimethylamine and / or ammonia or other primary and secondary amines; polyamidoamines; Copolymer of nonionic monomer and cationic monomer such as DADMAC or acryloyloxyethyltrimethylammonium chloride; cyanoguanidine modified polymer of urea / formaldehyde resin; melamine / formaldehyde polymer; urea / formaldehyde polymer; polyethyleneimine; cationic starch; And a blend of the above coagulants.

The amount of the particulate particulate cationic coagulant polymer of the present invention added to the stock or furnish is sufficient to obtain a substantial effect of coagulating the solids present in the stock or furnish. , Any amount. The total amount of the water-soluble coagulant polymer is about 0.0025-
It is in the range of 1.0% by weight, more preferably in the range of about 0.005 to 0.50% by weight (dry weight to dry weight of solids present in the stock or furnish).

As described above, the cationic coagulant is added to the concentrate before the fan pump 1, and the high molecular weight coagulant polymer is added to the concentrate after the concentrate passes through the fan pump 1, The material is added to the diluted stock solution after the diluted stock solution has passed through the pressure screen 2.

The first dilute stock solution may be any conventional papermaking stock solution such as traditional chemical pulp, eg, bleached and unbleached sulfate or sulfite pulp, mechanical pulp such as ground wood, thermomechanical treatment of deinked waste, etc. It can be made from pulp or chemical thermomechanically treated pulp, fiber filler compositions from coagulation or recovery processes, and any mixtures thereof.

The stock solution employed in the method of the present invention, and the final paper, are substantially unfilled (eg,
Less than 10% by weight in the furnish, generally less than 5% by weight), or the filler is up to 50% based on the dry weight of the stock solids, or It can be applied up to 40% by weight. If a filler is used, any conventional white filler is possible, such as calcium carbonate, kaolin clay, calcined kaolin, titanium oxide or talc, or combinations thereof. Preferably, the filler (if present) is added to the stock solution in a conventional manner before adding the particulate component.

The stock solution employed in the method of the present invention may contain any other known additives such as rosin, alum, neutral size or brightener. The stock solution also contains a fortifying or binding agent, which includes, for example, starches such as cationic starch. The pH of the stock solution is generally in the range of 4 to 9, and a particular advantage of the present invention is that it works effectively at low pH, e.g.

The amounts of fibers, fillers and other additives such as reinforcing agents or alum are all conventional. Typically, the dilute stock solution has a solids content of 0.1-3% by weight, or 0.1% by weight.
It has a fiber content of ２2% by weight. Dilute stock solutions usually have a solids content of 0.1 to 2% by weight.

The inorganic particulate material employed in the fine particle system of the present invention includes a trioctahedral aluminum-containing clay mineral selected from the group consisting of saponite, sauconite, and vermiculite, and is preferably saponite. These particles readily disperse in the aqueous pulp suspension during the papermaking process and enhance the surface properties of the final paper product. Generally, these particles are less than 80 μm, typically 1-10 μm, more typically 2 nm-2 μm.
m, preferably in the range of 1 nm to 1.2 μm.

Preference is given to particles having an average particle size of 1 μm which have the same particle size before addition to the stock solution or which have been milled to that size after addition to the stock solution. Conventional dispersants, for example water-soluble anionic polymers such as acidic polymers containing salts of acrylic or methacrylic groups, are used in a customary manner. For example, in order to ensure an appropriate fine particle size, the dispersant is added in an amount of about 0.1 to 3% by weight based on the dry weight of the inorganic particulate material.

We have found that saponite (Na _0.9 [M
g _6.0 ]) (Si _7.1 Al _0.9 ) O ₂₀ (OH ₄ ) was found to increase drainage and retention in the papermaking process and improve sheet formation.

[0051] Two sets of experiments were performed. In the first set, flocculants and saponite were added at the feed points shown in FIG. 1 to obtain drainage and retention results. In order to obtain the drainage, retention and sheet formation results, in the second set both coagulant and saponite were added at the feed point shown in FIG. 1 and at the feed point shown in FIG. And saponite were added.

The following examples illustrate the invention in more detail. These examples do not limit the scope of the invention.

(Example) Experimental set No. 1 set No. The following products were used in one experiment.

Hydrocol 875 is a high molecular weight cationic polyacrylamide polymer obtained from Allied Colloids.

Imvite 1016 is available from IMV Nevada (Amagosa Valley, Am
Argosa Valley, Nevada).

SMI 200 H-200 mesh is a ground saponite clay obtained from GSA Resources (Tucson, AZ).

Acme Clay is available from ECC International (Roswell,
Kaolin clay obtained from Georgia.

Experiment 1 A pulp slurry alkaline furnish was prepared. The furnish is Weyerhauser Pri
80% Albert HW pulp and Georgia Spec
It consisted of a formulation containing trum DP recycled pulp (Xerox grade).
The furnish was beaten with a lab scale Voith Allis Valley beater to 250 ml Canadian Standard Freeness (CSF) and diluted to a consistency of 0.5 wt% solids. The pH of the slurry was kept at approximately 7.8. This furnish is 2
Batch manufactured. To the first batch of furnish was added 5 wt% Acme clay as a filler based on the weight percent consistency of the pulp slurry. 2 of furnish
To the second batch, 20% by weight of Acme clay based on the weight percent consistency of the pulp slurry was added as a filler.

Preparation of Reagents Preparation of Water-Soluble Polymers Hydrocoll 875 polymer was first prepared in deionized water to a 1.0% by weight headbox consistency using a magnetic stirrer. Next, the amount was adjusted to 0.1% by weight based on the amount of deionized water to obtain two batches of pulp slurry in the drainage and retention test steps in this experiment.

Preparation of Saponite Samples Two samples of saponite were used during the set # 1 experiment. Sample 1 was SMI 200 H-200 mesh saponite, and Sample 2 was Imvite 1016 saponite.

5 g of each of the saponite samples 1 and 2 were added to 100 ml of deionized water, and
Mix in a Milton Beach mixer for 15 minutes, and add 1000 with deionized water.
Diluted to ml. Both samples 1 and 2 were mixed with a magnetic stirrer for an additional 15 minutes and allowed to hydrate for a minimum of 16 hours. Samples 1 and 2 were each mixed before adding to the pulp slurry as described below.

Drainability test 1 liter of each of the first and second batches, each containing 5% by weight of Acme clay filler and 20% by weight of Acme clay filler, were lighted in a square jar.
The mixture was mixed using an ening mixer. The mixer speed was kept constant at 1500 rpm for 10 seconds (shear mixing). The polymer solution was added to these two batches, and the mixture was further stirred at 1500 rpm for 1 minute. The mixer was stopped and the slurry was allowed to stand for 3 minutes.

The saponite sample 2 was added to the first batch of furnish containing 5% by weight kaolin clay filler and the second batch of furnish containing 20% by weight kaolin clay filler. Was added to a second batch of furnish containing 20% by weight kaolin clay filler. The resulting pulp slurry containing saponite, filler and polymer was poured five times back and forth between two beakers. The resulting pulp slurry was poured into a drain jar and shaken three times before draining the pulp slurry. The discharged water was collected for 30 seconds and weighed using a beaker weighing its own weight. A drainage test of these obtained pulp slurries was performed and plotted in FIGS.

Retention Test Turbidity The turbidity of the effluent is a measure of the retention of the system filler and microparticles.

A 240 ml furnish batch containing 5% by weight of kaolin clay filler was added to 1500
Mixing at rpm (shear mixing). Six pounds of dry polymer per ton of dry furnish were added to the furnish batch during agitation and agitated for 15 seconds. The turbidity of the effluent containing the polymer solution and 5% by weight of the filler was measured and plotted in FIG. Saponite Sample 1 was then added to the furnish at 12 pounds dry saponite per ton of dry furnish. The resulting pulp slurry was further stirred for 5 seconds. The turbidity of this furnish was measured and plotted as Sample 4 in FIG.

The turbidity test was performed using a Hach 2100P turbidity meter.

[0067] to furnish another 240ml including homemade sheet 5 wt% of kaolin clay filler was added polymer solution prepared above. An aliquot of the saponite solution slurry of Sample 1 was added to the furnish and mixed at 1500 rpm for an additional 5 seconds. The additive liquids are shown in Table 1, where the dry polymer loading is 6 pounds per ton of dry furnish and the dry saponite loading is 0, 6, and 12 pounds per ton of dry furnish.

[0068]

【table 1】

Handsheets were made using a standard TAPPI mold and a standard handmade sheet method.
Paper sheets were made and incinerated at 500 ° C. A pulp pad was also made using a ceramic Buchner filter paper funnel equipped with Whats41 41 ashless filter paper from Coors, USA.

Drainability Results Drainage data obtained from the first batch of furnish containing 5% kaolin clay filler are shown in a three-dimensional surface graph in FIG. 2 showing drainage versus polymer loading versus saponite loading. (Sample 1). 1.2 lbs / dry polymer polymer
Changed to dry finished sample ton-6.0 pounds / dry finished sample ton, saponite (
Sample 1) The amount added was varied from 0 to 18 pounds / ton of dry finished sample. It can be seen from the graph of FIG. 2 that the amount of wastewater expressed in ml increases as the amount of addition of the polymer and the saponite increases.

Second Batch Finished Paper Volume—20% Clay Filler—Saponite Sample 1 FIG. 3 shows the data for Saponite Sample 1, which plots the amount of wastewater versus polymer added versus saponite added for 20% clay filler. I have.

Second Batch Finished Paper Volume—20% Clay Filler—Saponite Sample 2 FIG. 4 shows the data for Saponite Sample 2, where the amount of wastewater versus polymer added versus saponite added for 20% clay filler is plotted. I have.

In FIGS. 3 and 4, saponite loading ranges from 0 to 24 pounds per ton of dry finished paper, and polymer loading ranges from 2.4 to 6.0 pounds per ton of dry finished paper.

Here, as the amount of addition of the polymer and the saponite increases, the amount of drainage expressed in ml increases.

As a result of the retention, the turbidity is a measure of the retention. High turbidity indicates high levels of fine solids and filler in the effluent, and therefore low levels of fine solids and filler retention.
The results are plotted in FIG. 5 for samples 3 and 4, and are discussed above.

From the results plotted in FIG. 5, the turbidity of sample 4 containing saponite and polymer was much lower than that of sample 3 without saponite, and the retention of filler and fine solids was due to the polymer and saponite being retained. Included sample 4 means greater.

Homemade sheet The results of these experiments are given in Table 1. The given filler retention values were determined by incineration of the homemade sheet at 500 ° C. Again, it can be seen that when saponite is added to the furnish, the filler retention increases.

As this initial set of experiments shows, the drainage and retention of microsolids and fillers can be increased by using a two-particulate particulate system, ie, a saponite and flocculant polymer.

Set No. 2 Experiment This set of experiments showed that the drainage and retention of microsolids and fillers was in either a binary or ternary particulate system including saponite and a polymeric flocculant, and optionally a coagulant. Indicates that it can increase.

[0080] The following examples are intended to illustrate the invention in more detail. These examples do not limit the scope of the invention in any way. The following products were used in these examples.

Polymer A was a high molecular weight cationic acrylamide / acryloyloxyethyl chloride obtained from Calgon (Pittsburgh, PA), containing about 90 mole% acrylamide and about 10 mole% acryloyloxyethyltrimethylammonium. It is a trimethyl ammonium copolymer.

Polymer B is a medium molecular weight homopolymer of diallyldimethylammonium chloride obtained from Calgon (Pittsburgh, PA).

Polymer C is a high molecular weight cationic acrylamide copolymer with a cationic charge of about 25% by weight, obtained from Ciba Specialty Chemicals.

Hydrocol 2D1 is a Ciba Specialty Chemical
Dried bentonite clay, montmorillonite, obtained from als.

Polymer D is a medium molecular weight dimethylamine / epichlorohydrin cationic polymer obtained from Calgon (Pittsburgh, PA).

[0086] Polymer E is a high molecular weight anionic acrylamide copolymer comprising about 70 mole% acrylamide and about 30 mole% acrylic acid obtained from Calgon (Pittsburgh, PA).

[0087] Polymer F is polyaluminum chloride obtained from ECC International (Pittsburgh, PA).

Polymer G is a medium molecular weight cationic copolymer of acrylamide and diallyldimethylammonium chloride obtained from ECC International, Pittsburgh, PA.

Polymer H is a medium molecular weight terpolymer of acrylamide, diallyldimethylammonium chloride and acrylic acid obtained from ECC International, Pittsburgh, PA.

The IMVITE 1016 is an IMV Nevada (Amargosa Val)
dry, saponite clay obtained from C.ley, NV).

Carbital 60 is dry ground calcium carbonate obtained from ECC International (Atlanta, Georgia).

Stalok 400 and Interbond C are available from A.D. E. FIG. Staley
Is a cationic starch obtained from Co., Ltd.

[0093] Hercon 70 is AKD size obtained from Hercules.

Examples 1-26 Examples 1-26 demonstrate the effectiveness of various formulations of the present invention in improving various sheet properties, including drainage, retention and formation, gloss and opacity of synthetic aqueous cellulose furnish. Shows sex. The furnish composition is designed to mimic furnish used in the manufacture of magazines, printing, and writing grade basesheets, free of coated or uncoated typical alkaline wood.

[0095] furnish formulations drainage and used in retention test, a synthetic furnish for homemade sheet production, were prepared of the following ingredients.

Fiber: 50/50% by weight bleached hardwood kraft / bleached softwood kraft Filler: 50/50% by weight ground calcium carbonate (Carbital 60)
) / Precipitated calcium carbonate Filler load: 20% by weight based on fiber solids Starch: 0.5% by weight based on fiber solids (Interbond C) Size: 0.25% by weight Hercon 70 (AKD) And concentrated to 2 wt% solids and purified in a laboratory scale Valley beater to 590 ml Canadian Standard Freeness. The starch, size and filler are added in this order to the refined pulp slurry.
The pH of the pulp slurry is typically 7.5 ± 0.3. The pulp slurry is further diluted with warm water to a consistency of about 1.0% by weight to provide a dilute stock solution for testing.

Drainage test method 1. Pour 200 ml (2 g solids) stock solution of 1 wt% headbox consistency into a square mixing jar and dilute to 500 ml with warm water. 2. The contents were mixed using a standard Brit jar type propeller mixer (1 inch diameter) with the following mixing time and speed conditions to simulate the addition of chemicals to the secondary fan pump inlet, fan pump outlet and pressurized screen outlet. .

[0098]

[Table A]

[0099] 3. 500 with the contents of the mixing jar fitted with a 100 mesh screen at the bottom
Transfer to ml graduated drain tube. Invert the tube 5 times to homogenize the stock solution. Remove the bottom stopper and measure the elution time for 100, 200 and 300 ml elution volumes. The 300 ml elution time of the untreated stock solution as a blank should preferably be at least 60 seconds. 4. The improvement in drainage obtained by the treatment was calculated as follows with respect to the drainage time of the untreated blank sample.

Drainage improvement% = [(untreated drainage time−treated drainage time) / untreated drainage time]
× 100 retention test method (FPR, FPAR, FPFR) 500 ml stock solution of head box consistency (1.0%) was taken at 1200 rpm
Pour into Brit jar with 70 mesh screen while stirring with. 2. Using the same mixing times / speeds used in the drainage test method to simulate the chemical additive points, add the following steps.

[0101]

[Table B]

A. The eluate is filtered through a Whatman 4 filter and the pad is dried at 105 ° C. The pad is incinerated at 500 ° C. for 2 hours, and the amount of retained ash is determined.

Production and Test of Handmade Sheet A handmade sheet was produced with a basis weight of 70 grams using a Noble & Wood handmade sheet mold. This device produces a 20 cm x 20 cm square handmade sheet. The mixing time / speed technique used for the handmade sheet making is the same as that used in the drainage test technique. The treated furnish samples were poured into the deckle box of a Noble & Wood handmade sheet machine and sheets were made using standard techniques known to those skilled in the art.

Table 2 shows the results.

[0105]

[Table 2]

Examples 5-8 plotted in FIG. 6 show that the addition of Polymer A before the press screen at a loading of 3-9 lb / ton and the addition of saponite after the press screen, This shows that the amount of drainage increased significantly, but the sheet formation loss was slight. The ash retention (FPAR) of the first filtration is greatest at 3 lbs. Saponite and decreases at higher loadings.

Examples 9-12 plotted in FIG. 7 show that the addition of the third component, cationic coagulant polymer B, selectively improved the ash retention (FPAR) of the first filtration, Changes in drainage and sheet formation were slight up to an addition of .1 pound stationary phase / ton. At higher loadings, FPAR continues to increase, but drainage slightly decreases and sheet formation drops sharply. Examples 14 and 17
In the absence of saponite, as shown in FIGS. 23 and 26, the drainage and retention are significantly lower.

Tables 3 and 4 show the results of Examples 27-50.

[0109]

[Table 3]

Examples 27 to 50 in Table 3 show the drainage performance of the present invention (Examples 28 to 32), the ordinary two-component polymer system (Examples 46 to 50), and the colloidal silica system (Examples 38 to 50).
42 and 43 to 45) and a bentonite system (Examples 33 to 37). In the example of the present invention (Example 29), which is equivalent to the drainage performance of the prior art example, at substantially the same level of drainage performance (Examples 29, 37, 40, 45, and 47) of these experimental systems, Only lower total loadings are required. Also, as shown in Table 4, the ash retention of the first filtration of the present invention is higher in the corresponding sheet formation than in the prior art.

[0111]

[Table 4]

Examples 51-77 Examples 51-77 of Table 5 demonstrate the effectiveness of the present invention in improving the effectiveness of various sheet properties, including drainage, retention and formation, brightness, and opacity of synthetic aqueous furnishes. Various formulations are shown. The furnish composition represents a typical furnish used in making base sheets for lightweight coated paper grades.

Preparation of Furnish Synthetic furnish for drainage and retention testing and for base sheet production was prepared with the following ingredients: Fiber: 45% by weight bleached softwood kraft (SWK) / 55% by weight % Chemical thermomechanical pulp (CTMP) Filler: calcined clay Filler load: 10% by weight based on dry fiber weight Alum: 0.5% by weight based on dry fiber weight CTMP is immersed in hot water for 15 to 20 minutes. It was then diluted to 1.56 wt% solids in water and purified to 200 ml Canadian Standard Freeness (CSF). Kraft softwood fiber (SWK) is separately immersed in water, diluted to 1.56% by weight, and 550CSF.
Was purified. The fibers were then blended with the calcined clay filler in the above proportions. The pH of the combined furnish was adjusted to 5.0 with dilute sulfuric acid, and the conductivity was adjusted to 2000 μ with sodium sulfate.
Adjusted to S / cm.

[0114]

[Table 5]

Examples 78-110 Examples 78-110 in Table 6 demonstrate the effectiveness of the formulations of the present invention in improving the drainage, retention, and sheet formation of synthetic aqueous furnishes. The furnish composition represents a typical furnish in the manufacture of base sheets for paperboard. With equivalent drainage performance, the present invention has improved ash retention and sheet formation over the prior art over the prior art.

Preparation of Furnish A synthetic furnish for drainage and retention tests and for the production of handmade sheets was prepared by the following procedure.

Disperse 360 grams of unbleached used corrugated paper (OCC) in warm water and dilute to 23 liters with deionized water. The pulp is refined to 300 CSF. 18 liters of this stock solution is diluted to 0.5% by weight consistency and the following salts are added to adjust the water character to the appropriate ionic strength (2000 μS / cm): a. 5.61 grams of calcium chloride b. 0.96 grams of potassium chloride c. 8.17 grams (50% by weight) of alum d. 15.96 grams of sodium sulfate e. 0.59 grams of sodium bicarbonate f. 0.97 grams of sodium silicate Adjust the pH to 5.0 with dilute sulfuric acid.

[0118]

[Table 6]

Examples 111-118 in Table 7 compare the performance of the invention in 100% OCC paperboard furnish with prior art bentonite and silica colloid systems. At the same drainage amount, the ash retention amount, the remaining retention amount, and the sheet formation (MK) are considerably improved in this embodiment.

[0120]

[Table 7]

Examples 119-145 Examples 119-145 of Table 8 are useful in improving the sheet properties of various formulations, including drainage, retention and formation, brightness and opacity of synthetic aqueous finished paper quantities. Shows sex. This furnish composition represents a typical groundwood pulp furnish used in the manufacture of newsprint base sheets.

Formulation of furnishes Synthetic furnishes used in drainage and retention tests and in the manufacture of handmade sheets were prepared using the following recipes and steps.

Fiber: 80% by weight CTMP / 10% by weight SWK / 10% by weight recovered newsprint Filler: calcined clay Filler load: 4% by weight on dry solids Alum: 50 lb / ton pH: 4.8-5 .2 CTMP was immersed in hot water (140 ° F) and defibrated in a blender for 15-20 minutes. The recovered newsprint was separately immersed in hot water and defibrated in a blender for 15 to 20 minutes. The softwood kraft was immersed in warm water for 2 hours and defibrated in a blender for 15-20 minutes.

[0124] CTMP, recovered newsprint and softwood kraft were blended together in the above proportions, and
Purified to 50-75 CSF at 56% by weight consistency. A calcined clay filler and then alum were added to the stock solution to bring the pH to about 4.8-5.2. The conductivity of the stock solution was adjusted to 2000 μS / cm using sodium chloride.

[0125]

[Table 8]

Examples 146-150 in Table 9 compare the performance of the present invention to the prior art at approximately equivalent and maximum displacements for a typical newsprint furnish. As shown in Table 9, the present invention provides significantly higher maximum undiluted solution drainage and improvements in sheet formation (MK) and sheet brightness at equivalent drainage at significantly lower additive levels than the prior art.

[0127]

[Table 9]

[0128] Example 151 commercially available device applications - the performance of lightweight coated paper present invention, 60 lbs / 3300ft ² was evaluated by commercially available papermaking machine for producing a lightweight coated wood-containing paper, typical commercial silica colloidal systems in the prior art And compared. Polymer A was fed at 0.2 pounds dry polymer / ton dry paper to the inlet of the pressure screen and saponite clay was fed at 4 pounds / ton dry paper to the exit of the pressure screen. As shown in Table 10, the present invention showed significant improvements in steam usage, sheet formation and retention of first filtration at comparable machine speeds. The variability of the retention control and the sheet moisture in the cross-sectional direction are also significantly reduced in the present invention.

[0129]

[Table 10]

The effectiveness of the present invention has also been demonstrated on other commercial papermaking machines producing 40 lb / 3300 ft ² light weight coated wood containing paper and compared to silica colloid systems typical in the prior art. In this evaluation, polymer A was fed at 0.25 lb dry polymer / ton dry paper to the entrance of the pressure screen and saponite clay was fed at 4 lb / ton dry paper to the exit of the pressure screen. As shown in Table 11, the present invention showed significant improvements in steam usage, sheet formation, headbox distribution consistency, and sheet brightness.

[0131]

[Table 11]

Example 152 Application of Commercial Equipment- Linerboard The performance of the present invention was evaluated on a commercial papermaking equipment producing a two-ply plywood linerboard.
Polymer A was fed to the entrance of the pressure screen at a loading of 0.2-0.75 pounds of additive per dry ton of paper. In addition, saponite is added in an amount of 3
It was fed through the discharge side of the pressure screen with an addition of ~ 7 pounds. The first filtration retention (FPR) increased from 63% to 86% and the first filtration ash retention (FPA)
R) increased from 10% to 50%. The concentrated stock solution flow was reduced by 10-17% and the clear cloudy leg excluding all solids was reduced by 50%.

The “MK formation” described above indicates a sheet formation measured by an M / K formation tester.

While particular embodiments of the present invention have been described by way of illustration, various modifications and details of the invention may be made without departing from the invention as defined in the appended claims. Seems obvious to one skilled in the art.

[Brief description of the drawings]

FIG. 1 is a sketch showing a portion of a typical papermaking apparatus in a preferred embodiment of the present invention and points of addition of fine particle based components.

FIG. 2 shows the first set of saponite samples of the example for a 1.5% clay filler.
It is a three-dimensional surface graph which shows the drainage amount-polymer addition amount-saponite addition amount.

FIG. 3 is a three-dimensional surface graph showing drainage versus polymer loading vs. saponite loading for a first set of saponite 1.20% clay fillers of the examples.

FIG. 4 is a three-dimensional surface graph showing the amount of wastewater vs. the amount of polymer added vs. the amount of saponite added for a first set of saponite 2.20% clay filler of the example.

FIG. 5 is a two-dimensional graph showing the turbidity of a sample containing saponite versus a sample containing no saponite.

FIG. 6 is a graph plotting the results of drainage, MK formation and ash retention (FPAR (%)) of the first filtration for Examples 5-8 of the present invention in the second set of Examples. It is.

FIG. 7 is a graph plotting the results of drainage, MK formation and ash retention (FPAR (%)) of the first filtration for Examples 9 to 12 of the present invention in the second set of Examples. is there.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR , BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS , JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZA, ZW (71) Applicant One Nelco Center, Naperville, Illinois 60563-1198, United States of America (72) Inventor Panfil, Daniel, Jay. United States, 31061 Georgia, Mildgeville, Waters Bend Drive N. E. 101 F term (reference) 4L055 AG17 AG27 AG73 AH18 AH50 EA32 FA10 FA22 GA06 GA16 GA19

Claims (12)

[Claims] 1. A paper furnish comprising a retention and drainage aid composition, wherein the furnish comprises from about 0.0025 to about 1.0% by weight based on the dry weight of solids in the furnish. An inorganic particulate material comprising an aluminum substituted trioctahedral clay mineral present in an amount of about 0.005 to about 2.0% by weight based on the dry weight of the solids in the furnish; A furnish comprising: 2. The composition according to claim 1, wherein the dry weight of the solids in the furnish is from about 0.0025 to
The paper product furnish of claim 1, further comprising a high charge density cationic coagulant present in an amount of about 0.5% by weight. 3. The paper product furnish according to claim 1, wherein the aluminum-substituted trioctahedral clay mineral is selected from the group consisting of saponite, sauconite, and vermiculite. 4. The paper furnish according to claim 3, wherein the aluminum-substituted trioctahedral clay mineral is saponite. 5. After the first high shear step and before the second high shear step, the high molecular weight polymer flocculant is added to the solids in the furnish in an amount of from about 0.0025 to about 0.0025 to dry weight of solids in the furnish.
Adding to the furnish in an amount of about 1.0% by weight; and after the second high shearing step, drying the inorganic particulate material comprising an aluminum-substituted trioctahedral clay mineral to dry the solids in the furnish. About 0.005 to about 2.0 based on weight
A method for producing a paper product, comprising a step of adding to a furnish in an amount of% by weight. 6. A high charge density cationic coagulant in an amount of about 0.0025 to about 0.5% by weight based on the dry weight of solids in the furnish prior to said first high shear step. The method of claim 5, further comprising the step of adding to the furnish. 7. The method of claim 5, wherein said aluminum-substituted trioctahedral clay mineral is selected from the group consisting of saponite, sauconite and vermiculite. 8. The method of claim 7, wherein said aluminum-substituted trioctahedral clay mineral is saponite. 9. A microparticulate composition suitable for use as a retention and drainage agent in a papermaking process, comprising an inorganic particulate material including a high molecular weight polymer flocculant and an aluminum substituted trioctahedral clay mineral. Characterized microparticle composition. 10. The composition according to claim 9, further comprising a high charge density cationic coagulant. 11. The composition according to claim 9, wherein said aluminum-substituted trioctahedral clay mineral is selected from the group consisting of saponite, sauconite and vermiculite. 12. The composition according to claim 11, wherein said aluminum-substituted trioctahedral clay mineral is saponite.