The present invention relates to a kind of filler that comprises calcium salt and cellulose derivative.The invention further relates to the application in papermaking of a kind of method for preparing this filler, this filler, a kind of wherein with this filler as the papermaking process of additive and the paper that comprises this filler.
Summary of the invention
Generally speaking, the present invention relates to a kind of filler that comprises calcium salt and cellulose derivative.Generally speaking, the invention further relates to a kind of filler that comprises calcium salt and carboxyl alkyl cellulose derivative.Generally speaking, the invention still further relates to and a kind ofly mix the method for preparing filler, this filler is used as Application of Additives and comprises this filler in papermaking paper with cellulose derivative through the material that will contain calcium salt.Generally speaking, the invention further relates to a kind of papermaking process of wherein this filler being introduced moisture cellulose suspension.
More particularly, the present invention relates to a kind of filler that comprises the calcium salt and the cellulose derivative of clean ionic group substitution value about at the most 0.65.The invention still further relates to a kind of filler that comprises the cellulose derivative of calcium salt and carboxyalkyl substitution value about at the most 0.65.The invention further relates to a kind of method for preparing filler, it comprises: the material that will contain calcium salt mixes with the cellulose derivative of clean ionic group substitution value about at the most 0.65.The invention still further relates to a kind of method for preparing filler, it comprises: the material that will contain calcium salt mixes with the cellulose derivative of carboxyalkyl substitution value about at the most 0.65.The invention further relates to a kind of filler that obtains through these methods.The invention further relates to a kind of papermaking process; It comprises: the filler that the aqueous suspension that contains cellulose fibre is provided, will comprise the cellulose derivative of calcium salt and clean ionic group substitution value about at the most 0.65 introduce suspension and with the suspension dehydration to form the paper web or the scraps of paper.The invention still further relates to a kind of papermaking process; It comprises: the filler of the cellulose derivative that the aqueous suspension that contains cellulose fibre is provided, will comprise calcium salt and carboxyalkyl substitution value about at the most 0.65 introduce suspension and with the suspension dehydration to form the paper web or the scraps of paper.In this papermaking process, can be through calcium salt and cellulose derivative being added as single composition together and filler being introduced cellulose suspension.
Detailed Description Of The Invention
The present invention provides a kind of new filler that is applicable to papermaking.It has surprisingly been found that according to filler of the present invention is feasible and can reduce and some relevant problems of filler of in papermaking, generally using and be impregnated in the paper.More particularly; Through filler of the present invention is used for papermaking process; Can provide and have the smoothness that superior printing characteristics can be for example high, high opacity and whiteness; Improved mechanical performance is the paper of dry strength, TENSILE STRENGTH, Scott associativity and bending rigidity and improved gluing effect for example.Comprise good and/or improved dehydration property and particulate retentivity by other advantages that the present invention showed, this has caused the advantage with regard to the runnability of paper machine.
When this filler is used in combination with cementing agent, has observed the invention enables and to have reduced the gluing demand and therefore improve gluing efficient usually.For dissimilar cementing agents, the cementing agent that comprises the cementing agent of non-cellulose and cellulolytic activity, particularly cellulolytic activity is ketene dimer and acid anhydrides for example, all shows the gluing efficient of raising.Especially, the invention provides the gluing efficient and the gluing stability of the raising that especially has high filler loadings and/or the paper fillers when using filler with high surface.
According to the present invention, can't expectedly observe and during simple processing, can make cellulose derivative and contain the material mixing of calcium salt and more effectively be adsorbed on or stick on the material that contains calcium salt.The filler that can filler of the present invention be regarded as modification, the perhaps filler of cellulose derivative processing.
According to the present invention, have been found that can be through will containing calcium salt material and cellulose derivative add together with premixed or pretreated form and obtain very excellent results in the cellulose suspension.Only a kind of component that the material preliminary treatment that will contain calcium salt with cellulose derivative provides a kind of independent processing of cellulose suspension is with the convenient manner of the filler that makes modification, can use the filler of this modification to replace or part replaces conventional filler.Do not receive the constraint of any theory, think that cellulose derivative is adsorbed on the material that contains calcium salt when these components are mixed.
Filler according to the present invention comprises calcium salt and cellulose derivative.The example of suitable calcium salt comprises: calcium carbonate, calcium sulfate and calcium oxalate, preferred calcium carbonate and its mixture.Calcium carbonate is the main component in lime stone, marble, chalk and the dolomite.Can directly obtain calcium carbonate, so and it is referred to as powdered whiting (" GCC ") by the above-mentioned natural stone kind that forms.Also can synthesize preparation calcium carbonate, usually it is referred to as winnofil (" PCC ").The material that preferably produces carbanion by calcium hydroxide with at aqueous phase for example alkali carbonate or carbon dioxide obtains calcium carbonate.GCC and PCC all can be used for the present invention, and preferred PCC comprises any for example rhombus of various crystal forms or the form of existence, prismatic, tabular, cube and the calcite of scalenohedron shape and the aragonite of needle-like.PCC has the about 20m of about 2-usually
2/ g is about the about 12m of 7-aptly
2The specific area of/g.
Calcium salt can be used as pure basically calcium salt, comprises the mixture of one or more calcium salts and exists.It can also exist with the form of mixtures of one or more other components.The term that uses among this paper " material that contains calcium salt " is meant a kind of material that comprises calcium salt and one or more other components of choosing wantonly.The example of suitable this type other components comprises: the aluminum oxide of the fiber of cellulose, lignocellulose or similar vegetable material or fibrillation, inorganic clay, kaolin, talcum, titanium dioxide, hydrogenation, barium sulfate etc.Preferably, when using, these other components are applicable to papermaking.
Comprise cellulose, lignocellulose or similarly the fiber or fibriilar of vegetable material contain in the material of calcium salt, can make at least the part calcium deposition on fiber or fibrillation.Fibriilar average thickness can be about the about 10 μ m of 0.01-, about at the most aptly 5 μ m, preferably about at the most 1 μ m.Fibriilar average length can be about the about 1500 μ m of 10 μ m-.The suitable examples of material that contains calcium salt comprises and is disclosed in United States Patent(USP) Nos. 5,731,080; 5,824,364; 6,251,222; Therefore composite in 6,375,794 and 6,599,391, the disclosure content of these patents are incorporated herein by reference.This of commercially available acquisition type composite comprises the SuperFill
of M-Real Oy.
Further comprise cellulose derivative according to filler of the present invention.Preferably this cellulose derivative be water-soluble or at least part water-soluble or aqueous dispersion, preferably water-soluble or part is water-soluble at least.Preferably, this cellulose derivative is ionic.This cellulose derivative can be anionic, cationic or both sexes, and is preferably anionic or both sexes.The example of suitable cellulose derivative comprises cellulose ether, the cellulose ether of anion and both sexes for example, preferred anionic cellulose ether.Cellulose derivative preferably has ion or charged group, or substituting group.The example of ions with proper group comprises anionic group and cation group.The example of suitable anionic group comprises: carboxylate is for example sulfoalkyl, phosphate and phosphonate groups of carboxyalkyl, sulfonate for example, and wherein alkyl can be methyl, ethyl, propyl group and its mixture, is suitably methyl; Aptly, cellulose derivative contains anionic group, comprises for example carboxyalkyl of carboxylate groups.The counter ion counterionsl gegenions of anionic group are alkali metal or alkaline-earth metal normally, is suitably sodium.
Example according to the suitable cation group of cellulose derivative of the present invention comprises: amine salt, be suitably tertiary ammonium salt, and quaternary ammonium group, be preferably quaternary ammonium group.Being connected substituting group on the nitrogen-atoms of amine and quaternary ammonium group can be identical or different and can be selected from alkyl, cycloalkyl and alkoxyalkyl, and one, two or more substituting group can form heterocycle with nitrogen-atoms.These substituting groups comprise about 24 carbon atoms of 1-independently of one another usually, preferred about 8 carbon atoms of 1-.The nitrogen of cation group can link to each other with the cellulose or derivatives thereof by means of atomic link, and these atoms comprise carbon atom and hydrogen atom and optional O and/or N atom aptly.Usually, atomic link is to contain 2-18, is suitably 2-8 carbon atom, randomly by one or more hetero atoms for example O or N interrupts or substituted alkylidene, for example alkylidene oxygen base or hydroxyl propylidene.The cellulose derivative of preferred cation group comprises through making the cellulose or derivatives thereof and be selected from 2, the quaternizing agent reaction of 3-epoxypropyl trimethyl ammonium chloride, 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride and its mixture and obtain those.
Cellulose derivative of the present invention can contain non-ionic group; For example alkyl or hydroxyalkyl such as methylol, ethoxy, hydroxypropyl, hydroxyl butyl and its mixture, for example ethoxy methyl, hydroxypropyl methyl, hydroxyl butyl methyl, ethoxy ethyl, hydroxypropyl etc.In a preferred embodiment of the invention, cellulose derivative contains ionic group and non-ionic group.
Example according to the plain derivative of suitable fibers of the present invention comprises: carboxyl alkyl cellulose for example carboxymethyl cellulose, carboxyethyl cellulose, carboxy-propyl cellulose, sulfoethyl carboxymethyl cellulose, carboxymethyl hydroxyethyl cellulose (" CM-HEC "), wherein cellulose is preferably carboxymethyl cellulose (" CMC ") by the substituted carboxymethyl cellulose of one or more nonionic substituting groups.The example of suitable cellulose derivative comprises with their preparation method and is disclosed in United States Patent(USP) No. 4,940, those in 785, and therefore this patent is incorporated herein by reference.
According to a preferred embodiment of the invention, filler comprises: the fiber or the fibriilar calcium salt and the cellulose derivative that contains cation group that contain cellulose or lignocellulose.This cation group can be any of cited in this application those.
In another preferred embodiment of the present invention, filler comprises: basically not the fiber of cellulose or lignocellulose or fibriilar calcium salt with can be the cellulose derivative of anion, CATION or both sexes.
The term that uses among this paper " substitution value " or " DS " are meant the number in replacement ring site of β-glucose anhydro ring of cellulose derivative.Owing on cellulosic each glucose anhydro ring, have three hydroxyls to can be used for replacing, so the maximum of DS is 3.0.According to a preferred embodiment of the invention, the substitution value (" DS of the clean ionic group of cellulose derivative
NI") about at the most 0.65, promptly cellulose derivative has clean ion average substitution degree/each glucose unit of about at the most 0.65.It can be anionic only, clean cationic or clean neutrality that this clean ion replaces.When clean ion replaces is clean when anionic, have the excessive anionic group of remainder (average of the average-cation group of the anionic group of clean anionic group=each glucose unit, if any) and DS
NISubstitution value (" DS with clean anionic group
NA") identical.When clean ion replaces is clean when cationic, have the excessive cation group of remainder (average of the average-anionic group of the cation group of clean cation group=each glucose unit, if any) and DS
NISubstitution value (" DS with clean cation group
NC") identical.When clean ion replacement was clean neutrality, if any, the anionic group of each glucose unit was identical with the average number of cation group, and DS
NIAnd DS
NAAnd DS
NCBe 0.According to another preferred embodiment of the present invention, carboxyalkyl the substitution value (" DS of cellulose derivative
CA") about at the most 0.65, promptly cellulose derivative has carboxyalkyl average substitution degree/each glucose unit of about at the most 0.65.Carboxyalkyl is suitably carboxymethyl, so the DS of indication among this paper
CASubstitution value (" DS with carboxymethyl
CM") identical.According to these embodiments of the present invention, DS
NI, DS
NA, DS
NCAnd DS
CABe generally about at the most 0.60 independently of one another, about at the most aptly 0.50, preferably about at the most 0.45, more preferably about at the most 0.40, and DS
NI, DS
NA, DS
NCAnd DS
CABe generally at least 0.01 independently of one another, aptly at least about 0.05, preferably at least about 0.10, more preferably at least about 0.15.DS
NI, DS
NA, DS
NCAnd DS
CAScope to be about 0.01-independently of one another usually about 0.60, it is about 0.50 to be about 0.05-aptly, it is about 0.45 preferably to be about 0.10-, is more preferably 0.15-about 0.40.
The cellulose derivative of anion or both sexes has anion the substitution value (" DS of 0.01-about 1.0 usually
A"), as long as DS
NIAnd DS
NASuch as among this paper definition; Aptly from about 0.05, preferably from about 0.10, more preferably from about 0.15, and arrive aptly about at the most 0.75, preferably about at the most 0.5, more preferably about at the most 0.4.The cellulose derivative of CATION or both sexes can have CATION the substitution value (" DS of 0.01-about 1.0
C"), as long as DS
NIAnd DS
NCSuch as among this paper definition; Aptly from about 0.02, preferably from about 0.03, more preferably from about 0.05, and arrive aptly about at the most 0.75, preferably about at the most 0.5, more preferably about at the most 0.4.Cation group is suitably quaternary ammonium group, so the DS of indication among this paper
CThe identical (" DS of substitution value with quaternary ammonium group
CN").For both sexes cellulose derivative of the present invention, DS
AOr DS
CCertainly be higher than 0.65, as long as DS
NAAnd DS
NCRespectively such as among this paper definition.For example, if DS
ABe 0.75 and DS
CBe 0.15, DS then
NABe 0.60.
Having as above, the example of the plain derivative of suitable fibers of the substitution value of definition is included in the water-soluble low DS carboxyl alkyl cellulose derivative that disclose in the common pendent patent application with the name submission of Akzo Nobel N.V. same date.Based on the gross weight of dry cellulosic derivative, this water-soluble cellulose derivative has the solubility of 85wt% at least aptly in the aqueous solution, preferred 90wt% at least, more preferably 95wt% at least, most preferably 98wt% at least.
Cellulose derivative has at least 20,000 dalton usually, and preferably at least 50,000 daltonian mean molecule quantity, and mean molecule quantity is 1,000,000 dalton at the most usually, preferably 500,000 dalton at the most.
Preferably, in filler according to the present invention, cellulose derivative part at least is adsorbed on or is connected on the calcium salt or other components that is present in the material that contains calcium salt.Aptly, at least about 10wt%, preferably at least about 30wt%, more preferably at least about 45wt%, most preferably the cellulose derivative at least about 60wt% is adsorbed on or is connected on the calcium salt or other components that is present in the material that contains calcium salt.
Based on the solid weight of filler-, have the calcium salt content of 0.0001wt% at least usually according to filler of the present invention promptly based on the dry weight of filler; This calcium salt content can be about the about 99.5wt% of 0.0001-, is about the about 90wt% of 0.1-aptly, preferably is about the about 80wt% of 60-.Based on the solid weight of filler, this filler has the cellulose derivative content of 0.01wt% at least usually; This cellulose derivative content can be about the about 30wt% of 0.01-, is about the about 20wt% of 0.1-aptly, preferably is about the about 10wt% of 0.3-.
Can be with filler according to the present invention as providing by water-free basically solid material.Also can it be provided as Aquo-composition.Depend on the application of preparation method and expection, the content of water or water can change in wide scope.
The invention still further relates to a kind of method for preparing filler; It comprises: with cellulose derivative for example defined any cellulose derivative and the material that contains calcium salt that comprises calcium salt and optional one or more other components, for example defined any material mixing that contains calcium salt among this paper among this paper.This cellulose derivative and the material that contains calcium salt are aptly so that provide the amount use that has like the filler of defined cellulose derivative and calcium salt content among this paper according to of the present invention.
The cellulose derivative of using can be used as solid with the material that contains calcium salt or exists with Aquo-composition and its mixture.The material that contains calcium salt exists as material in small, broken bits aptly.Can be through cellulose derivative being added filler with intermittence, semi-batch or continuous method, perhaps vice versa and the realization mixing.According to a preferred embodiment of the invention, cellulose derivative is added in the Aquo-composition of the material that contains calcium salt as solid, and the composition of acquisition is effectively disperseed so that cellulose derivative is dissolved aptly.Preferably, arrive alkaline water, be suitably the aqueous solution, then its Aquo-composition with the material that contains calcium salt is mixed and mixes through the neutrality that at first forms cellulose derivative.With the material mixing that contains calcium salt before, can the water of cellulose derivative be carried out preliminary treatment for example homogenizing, centrifugation and/or filtration, if for example under situation about having, undissolved cellulose derivative is separated from aqueous phase.
Preferably, with cellulose derivative with contain the material mixing of calcium salt so that the part cellulose derivative is adsorbed on or is connected on the material that contains calcium salt at least, preferred so that be difficult to it is removed from this material through dilute with water.This can realize through under the sufficiently long time, mixing so that can be adsorbed on the attachment.Aptly, incorporation time is at least about 1 minute, preferably at least about 5 minutes, more preferably at least about 10 minutes, most preferably at least about 20 minutes.If hope to reach the connection of high level, even the incorporation time of several hours (1-10 hour) is fine also.Aptly; Will be at least about 10wt%; Preferably at least about 30wt%, more preferably at least about 45wt%, most preferably the cellulose derivative at least about 60wt% shifts and is adsorbed on or is connected on the calcium salt or other components that is present in the material that contains calcium salt from aqueous phase.
Usually the pH of water that regulates cellulose derivative is so that about 13 at about 4-, and preferably about 6-is about 10, more preferably from about the special fiber element derivative of absorption use under the value of 7-about 8.5.Can suitable alkali or acid be used to regulate pH.The example of suitable alkali comprises alkali-metal bicarbonate and carbonate and alkali metal hydroxide, is suitably sodium acid carbonate, sodium carbonate and NaOH.The example of suitable acid comprises inorganic acid, organic acid and hydrochlorate, is suitably for example alum of sulfuric acid and its hydrochlorate.Generally speaking, to the pH of neutrality, the higher but solubility of the adsorbance of cellulose derivative reduces at lower pH-promptly about 4.0, and adsorbance reduces but solubility raises under higher pH.
Temperature is not crucial; Temperature is about about 100 ℃ of 10-usually in the operation under non-pressurised condition, about 80 ℃ of preferably about 20-.Yet higher temperature is more favourable, and during mixing the temperature of Aquo-composition is about about 70 ℃ of 30-aptly, and more preferably from about 40-is about 60 ℃.
When using when except calcium salt, also containing other components for example the fiber or fibriilar of cellulose or lignocellulose containing the material of calcium salt; The mixing of cellulose derivative can be carried out on fibrillation or fiber with calcium precipitation with being connected simultaneously, perhaps after deposition, carries out.Can also before deposition, add cellulose derivative.In this case, during pulling an oar or after making beating, add cellulose derivative with independent absorption.Cellulose derivative can be adsorbed on or be connected on the material that contains calcium salt or fiber or the fibrillation surface and/or absorb in fiber or the fibrillation.The method that similar cellulose derivative is adsorbed on the similar filler material is disclosed in United States Patent(USP) Nos. 5,731,080; 5,824,364; 6,251,222; In 6,375,794 and 6,599,391, the disclosure content of these patents is hereby incorporated by.
The filler that obtains through method of the present invention can former state be used for for example papermaking.If exist, then can it directly be used or can be dried when needed for example to simplify transportation as Aquo-composition.
The invention still further relates to a kind of papermaking process; It comprises: provide the aqueous suspension (" cellulose suspension ") that contains cellulose fibre, with filler for example among this paper defined any filler introduce cellulose suspension and with the cellulose suspension fluid dewatering to form the paper web or the scraps of paper.Preferably, through it being added as single composition and filler being introduced cellulose suspension.As selection, can or contain the material (for example defined any material that contains calcium salt among this paper) of calcium salt with calcium salt with cellulose derivative (for example defined any cellulose derivative among this paper) adds in the cellulose suspension separately and original position formation filler in cellulose suspension.
In the method, certainly other components are introduced cellulose suspension.The example of these components comprises: conventional fillers, fluorescent whitening agent, cementing agent, filter aid and retention agent, dry strength reagent, wet strength reagent etc.The example of suitable conventional fillers comprises: kaolin, china clay, titanium dioxide, gypsum, talcum, natural and synthetic calcium carbonate for example chalk, grind marble and winnofil, the aluminum oxide of hydrogenation (three aluminium hydroxide), calcium sulfate, barium sulfate, calcium oxalate etc.When will filler according to the present invention using, based on the dry weight of whole fillers, according to filler of the present invention 1wt% at least with conventional fillers; At least 5wt% aptly; Preferred 10wt% at least, more preferably at least about 20wt%, the amount of about 99wt% exists at the most aptly.The example of suitable cementing agent comprises: the active cementing agent of non-cellulose is for example based on the cementing agent of rosin, such as the soap based on rosin, based on the emulsion/dispersion liquid of rosin; With the cementing agent of cellulolytic activity for example acid anhydrides such as the emulsion/dispersion liquid of succinyl oxide (ASA), alkenyl and alkyl ketene dimer (AKD) and polymer.The example of suitable aid and retention agent comprises: the organic polymer product is CATION, anion and non-ionic polymers for example, comprises cationic polyethyleneimine, CATION, anion and non-ionic polyacrylamide, cationic polyamine, cationic starch and cation guar gum; Inorganic material, for example aluminium compound, anionic microparticles material are such as for example bentonite, the imvite of silica gel base particle, smectites clay; Colloidal alumina and its combination.The example of suitable aid and retention agent combination comprises cationic polymer and anionic microparticles material, for example cationic starch and anion silicon matrix particle, PAMC and anion silicon matrix particle and PAMC and bentonite or imvite.The example of suitable wet strength reagent comprises polyamine and polyaminoamide.The paper that contains with good grounds filler of the present invention and cationic starch shows very good strength character.
According to a preferred embodiment of the invention, at least a cementing agent is introduced cellulose suspension to make the sized paper that contains filler.Preferably, this cementing agent is the cellulolytic activity cementing agent of type mentioned among this paper.Suitable ketene dimer has following general formula (I), wherein R
1And R
2Represent saturated or undersaturated alkyl, be generally saturated hydrocarbons, these alkyl contain 8-36 carbon atom aptly, are generally the straight or branched alkyl for example cetyl and the octadecyl that contain 12-20 carbon atom.Ketene dimer under 25 ℃, can be liquid at ambient temperature-promptly aptly under 20 ℃.Usually, acid anhydrides can be characterized by following general formula (II), wherein R
3And R
4Can be identical or different and expression contain the saturated or undersaturated alkyl of 8-30 carbon atom, perhaps R aptly
3And R
4Can form 5 to 6 yuan of rings with-C-O-C-part, this ring is randomly further contained the hydrocarbyl substituted of 30 carbon atoms at the most.The example of the acid anhydrides of commercial use comprises alkyl and alkenyl succinic anhydrides, is in particular different octadecylene base succinyl oxide.
Suitable ketene dimer, acid anhydrides and organic isocyanate comprise and be disclosed in United States Patent(USP) No. 4,522, the compound in 686, and therefore this patent is incorporated herein by reference.
Can filler according to the present invention be added cellulose suspension with the amount that can in wide scope, change, this especially depend on the type of cellulose suspension, prepared paper type, add point etc.Based on the weight of dried fiber, usually with the about 50wt% of 1-, the about 40wt% of about aptly 5-, the amount of the about 30wt% of about usually 10-adds filler.Therefore,, has the about 50wt% of 1-usually, the about 40wt% of about aptly 5-, the filer content of the present invention of the about 30wt% of about usually 10-according to paper of the present invention based on the weight of dried fiber.
When using other components in the method; Can these components be added cellulose suspension with the amount that can in wide scope, change, this especially depend on type, the filer content of the type of these components and quantity, cellulose suspension, prepared paper type, add and put etc.Usually be at least about 0.01wt% with weight, at least about the amount of 0.1wt% cementing agent introduced cellulose suspension aptly, and the upper limit is about 2wt%, about aptly 0.5wt% usually based on dried fiber.Generally speaking, with filter aid and retention agent to introduce cellulose suspension with the amount that produces better drainage and/or retentivity of comparing that when not using these auxiliary agents, obtains.Usually with filter aid and retention agent, dry strength reagent and wet strength reagent independently of one another to be at least about 0.001wt% based on dried fiber, introduce at least about the amount of 0.005wt% usually, and the upper limit is about 5wt%, about aptly 1.5wt% usually.
The term that uses among this paper " paper " not only comprises paper and its product, and comprises sheet or the web-shaped product that other contain cellulose fibre, for example paper and cardboard and products thereof.This method can be used for preparing paper by the aqueous suspension of different types of cellulose (cellulose) fiber, and these suspension will contain aptly based on dry and be 25wt% at least, preferred this fibrid of 50wt% at least.Cellulose fibre can comprise the fiber of timber or annual plant or perennial plant based on fibrillation and/or regenerated fiber.Cellulose suspension can contain timber or not contain timber; And it can be based on the fiber that is obtained from following material: chemical pulp is sulfate, sulphite and organic solvent paper pulp for example; Mechanical pulp is heat-mechanical pulp, chemistry-Re-mechanical pulp, refining paper pulp and groundwood pulp for example; Hardwood and cork, and can be based on the regenerated fiber that randomly is obtained from de inked pulp and its mixture.Cellulose suspension has neutral pH to alkaline range aptly, and for example about 6-is about 10, preferably about 6.5-about 8.0.
Can be with the paper drying, coating and the calendering that make.Can use for example following material coated paper: calcium carbonate, gypsum, alumina silicate, kaolin, aluminium hydroxide, magnesium silicate, talcum, titanium dioxide, barium sulfate, zinc oxide, synthetic dyestuff and its mixture.
The grammes per square metre of the paper that makes can change in wide scope, and this depends on the type of the paper that makes; Usually, grammes per square metre is about the about 500g/m of 20-
2, the about 450g/m of about aptly 30-
2, the preferred about 110g/m of 30-
2Preferably, the fine paper that the present invention is used to prepare uncoated and the offset paper that applies, electrophotographic paper, randomly contains the uncoated of mechanical pulp and apply, and writing paper and blue printing paper.A kind of especially preferred product is the offset paper that has wherein combined the coating of high gloss and high opacity and volume.
In following examples, further set forth the present invention, however these embodiment and be not intended to restriction the present invention.Part and % relate separately to weight portion and wt%, unless otherwise indicated.
Embodiment 1
Prepare according to filler of the present invention and the filler that is used for comparison through the material processed that will contain calcium salt with cellulose derivative.The cellulose derivative of using is DS
NI(DS
CA=DS
CM=DS
A=DS
NA=DS
NI) be respectively 0.3,0.32 and 0.7 carboxymethyl cellulose (" CMC ").The another kind of CMC that uses is DS
CA=DS
CM=DS
A=0.4; DS
C=DS
QN=0.17; And DS
NI=DS
NAThe quaternary ammonium carboxymethyl cellulose of=0.4-0.17=0.23 (" QN-CMC ").The mean molecule quantity of the cellulose derivative of using is 100,000-400,000.The material that contains calcium salt that uses is that surface area is respectively 5.7 and 10.0m
2The different winnofil of/g (" PCC ").The material that the another kind that uses contains calcium salt is SuperFill
(PCC on the paper pulp particulate).
Concentration through CMC being dissolved in water to 0.5wt% prepares filler.After this, with under about 50 ℃ temperature, mixing in the CMC composition adding PCC filler slurries that obtain and at 25-45 minute.According to filler of the present invention (" product of the present invention ") and the filler (" comparative product ") that is used for comparison as follows:
Product 1 of the present invention (" IP1 "): CMC (DS
NI0.3) PCC (5.7m that handles
2/ g)
Product 2 of the present invention (" IP2 "): CMC (DS
NI0.3) PCC (10m that handles
2/ g)
Product 3 of the present invention (" IP3 "): CMC (DS
NI0.32) SuperFill that handles
Product 4 of the present invention (" IP4 "): QN-CMC (DS
NI0.23) SuperFill that handles
Comparative product 1 (" CP1 "): CMC (DS
NI0.7) PCC (5.7m that handles
2/ g)
Comparative product 2 (" CP2 "): SuperFill
Embodiment 2
To the gluing of paper prepared in accordance with the present invention estimate and with the paper that uses for comparison purposes relatively.Use prepares according to paper of the present invention according to the IP1 of embodiment 1.Use is according to the CP1 of embodiment 1 and use the not filler preparation of cellulose derivative to be used for the paper of comparison.
That form by chemical pulp and contain the pulp preparation scraps of paper of the untreated PCC of varied number as shown in table 1 (wt% is based on dried paper).In pulp suspension, add the dried fiber of 2.0kg/ ton according to the filler of embodiment 1 and the filler of non-cellulose derivative; 3.0kg/ the ton dried fiber AKD (aqueous dispersion Eka Keydime C223) and comprise cationic starch (Eka PL 1510) and the maintenance system of silica dioxide granule (Eka NP 780).Cationic starch and silica dioxide granule add with the amount of the dried fiber of 0.15kg/ ton.Addition sequence is following:
The adding of the PCC that CMC handles: 0 second
The adding of AKD dispersion liquid: 30 seconds
The adding of cationic starch: 45 seconds
The adding of silica dioxide granule: 60 seconds
Scraps of paper moulding: 75 seconds
Use dynamic scraps of paper make-up machine (" Formette ", CTP Grenoble) to prepare the scraps of paper according to standard method.In order to set up the gluing result, use Cobb
60(SCAN-P12:64) method.Table 1 shows the result of acquisition.
Table 1
Test No. |
The PCC content of paper |
Filler |
Cobb
60 |
1 |
18% |
CP1 |
45 |
2 |
19% |
IP1 |
25 |
Embodiment 3
In this embodiment, estimate PCC that wherein (i) handle CMC add pulp suspension and (ii) with CMC and PCC (being untreated) add separately pulp suspension according to papermaking process of the present invention.
By use among the embodiment 2 and contain based on dried paper and be the untreated PCC of 30wt% (surface area 10m
2/ g) or CMC (DS
NI0.3) PCC (10m that handles
2/ g) the pulp preparation scraps of paper of the same type of (according to the IP2 of embodiment 1).In pulp suspension, add the dried fiber of 4kg/ ton cationic starch (PB970), the dried fiber of 3.0kg/ ton AKD (moisture gluing dispersion liquid Eka Keydime C223) and comprise the maintenance system of PAMC (Eka PL1310) and silica dioxide granule (Eka NP780).PAMC and silica dioxide granule all add with the amount of the dried paper of 0.20kg/ ton.When using untreated PCC, add the DS of 1.0kg/ ton separately
NIBe 0.3 CMC.When adding the PCC of CMC processing, do not add CMC separately.Addition sequence is following:
The adding of cationic starch: 0 second
The adding of the untreated PCC of PCC/ that CMC handles: 30 seconds
The independent adding of CMC: 35 seconds
The adding of AKD: 45 seconds
The adding of PAMC: 60 seconds
The adding of silica dioxide granule: 75 seconds
Scraps of paper moulding: 90 seconds
Estimate the scraps of paper as in Example 2.The result is shown in Table 2.
Table 2
Test No. |
The adding mode |
Filler |
Cobb
60 |
1 |
Add separately |
Untreated PCC+CMC |
65 |
2 |
Add the PCC that CMC handles |
?IP2 |
35 |
Embodiment 4
In papermaking process, use and estimate the product of embodiment 1.With the method that is similar to embodiment 3 by contain bardwood pulp that 70wt% mixes and 30wt% respectively under 22 ° and 25 ° of SR the fiber furnish of the softwood pulp of refining prepare the scraps of paper; Except not using cationic starch and SuperFill
filler (IP3 and IP4) that uses untreated SuperFill
filler (CP2) or CMC to handle, the amount that these fillers so that obtain contain the scraps of paper of 30wt%SuperFill
filler adds.Addition sequence is following:
The adding of SuperFill
filler: 0 second
The adding of PAMC: 45 seconds
The adding of silica dioxide granule: 75 seconds
The adding of AKD: 90 seconds
The result is described in the table 3.
Table 3
Test No. |
Filler |
Cobb
60 |
1 |
CP2 |
80 |
2 |
IP3 |
50 |
3 |
IP4 |
21 |