JP5587154B2 - Composite particles, composite particle internal paper and coated paper - Google Patents
Composite particles, composite particle internal paper and coated paper Download PDFInfo
- Publication number
- JP5587154B2 JP5587154B2 JP2010273003A JP2010273003A JP5587154B2 JP 5587154 B2 JP5587154 B2 JP 5587154B2 JP 2010273003 A JP2010273003 A JP 2010273003A JP 2010273003 A JP2010273003 A JP 2010273003A JP 5587154 B2 JP5587154 B2 JP 5587154B2
- Authority
- JP
- Japan
- Prior art keywords
- particles
- paper
- composite
- silica
- heat treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000011246 composite particle Substances 0.000 title claims description 118
- 239000002245 particle Substances 0.000 claims description 310
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 134
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 131
- 238000010438 heat treatment Methods 0.000 claims description 69
- 239000000377 silicon dioxide Substances 0.000 claims description 66
- 239000004408 titanium dioxide Substances 0.000 claims description 62
- 238000000034 method Methods 0.000 claims description 58
- 230000008569 process Effects 0.000 claims description 40
- 239000002994 raw material Substances 0.000 claims description 39
- 230000018044 dehydration Effects 0.000 claims description 22
- 238000006297 dehydration reaction Methods 0.000 claims description 22
- 230000004931 aggregating effect Effects 0.000 claims description 21
- 238000010298 pulverizing process Methods 0.000 claims description 21
- 239000003795 chemical substances by application Substances 0.000 claims description 19
- 239000011247 coating layer Substances 0.000 claims description 12
- 239000010802 sludge Substances 0.000 claims description 11
- 239000010410 layer Substances 0.000 claims description 3
- 239000002002 slurry Substances 0.000 description 63
- 238000000576 coating method Methods 0.000 description 41
- 239000011248 coating agent Substances 0.000 description 40
- 230000002776 aggregation Effects 0.000 description 33
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 32
- 239000000047 product Substances 0.000 description 26
- 238000004220 aggregation Methods 0.000 description 25
- 239000000945 filler Substances 0.000 description 23
- 238000002485 combustion reaction Methods 0.000 description 22
- 208000005156 Dehydration Diseases 0.000 description 21
- 238000010521 absorption reaction Methods 0.000 description 20
- 238000004519 manufacturing process Methods 0.000 description 20
- 239000003921 oil Substances 0.000 description 20
- 235000019198 oils Nutrition 0.000 description 20
- 238000007639 printing Methods 0.000 description 20
- 125000002091 cationic group Chemical group 0.000 description 19
- 239000002761 deinking Substances 0.000 description 18
- 239000000049 pigment Substances 0.000 description 17
- 241000628997 Flos Species 0.000 description 16
- 229910000019 calcium carbonate Inorganic materials 0.000 description 16
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 15
- 230000000694 effects Effects 0.000 description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 15
- 239000002253 acid Substances 0.000 description 14
- 239000000178 monomer Substances 0.000 description 14
- 238000002156 mixing Methods 0.000 description 12
- 239000007787 solid Substances 0.000 description 12
- 239000007864 aqueous solution Substances 0.000 description 11
- 238000006243 chemical reaction Methods 0.000 description 11
- 239000007789 gas Substances 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 10
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 10
- 229910052799 carbon Inorganic materials 0.000 description 10
- 239000000976 ink Substances 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 9
- 239000002131 composite material Substances 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- 229920002472 Starch Polymers 0.000 description 8
- 238000005054 agglomeration Methods 0.000 description 8
- 229920001577 copolymer Polymers 0.000 description 8
- 238000009826 distribution Methods 0.000 description 8
- 238000001035 drying Methods 0.000 description 8
- 229910052500 inorganic mineral Inorganic materials 0.000 description 8
- 239000007788 liquid Substances 0.000 description 8
- 239000011707 mineral Substances 0.000 description 8
- 229920000642 polymer Polymers 0.000 description 8
- 239000008107 starch Substances 0.000 description 8
- 235000019698 starch Nutrition 0.000 description 8
- 239000000126 substance Substances 0.000 description 8
- 229940048053 acrylate Drugs 0.000 description 7
- 239000000654 additive Substances 0.000 description 7
- 229910052910 alkali metal silicate Inorganic materials 0.000 description 7
- 239000001569 carbon dioxide Substances 0.000 description 7
- 229910002092 carbon dioxide Inorganic materials 0.000 description 7
- 150000001768 cations Chemical class 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 229920001131 Pulp (paper) Polymers 0.000 description 6
- 238000000149 argon plasma sintering Methods 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 6
- 238000007664 blowing Methods 0.000 description 6
- 229920000126 latex Polymers 0.000 description 6
- 239000004816 latex Substances 0.000 description 6
- 239000002585 base Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 239000005416 organic matter Substances 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- 239000000523 sample Substances 0.000 description 5
- -1 satin white Substances 0.000 description 5
- 230000008719 thickening Effects 0.000 description 5
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical compound NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 4
- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- 229920006317 cationic polymer Polymers 0.000 description 4
- 235000013339 cereals Nutrition 0.000 description 4
- 239000008394 flocculating agent Substances 0.000 description 4
- 230000006872 improvement Effects 0.000 description 4
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 229920001281 polyalkylene Polymers 0.000 description 4
- 229920000768 polyamine Polymers 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 239000011164 primary particle Substances 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 4
- 238000007711 solidification Methods 0.000 description 4
- 230000008023 solidification Effects 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 229920001059 synthetic polymer Polymers 0.000 description 4
- 239000000454 talc Substances 0.000 description 4
- 229910052623 talc Inorganic materials 0.000 description 4
- FZGFBJMPSHGTRQ-UHFFFAOYSA-M trimethyl(2-prop-2-enoyloxyethyl)azanium;chloride Chemical compound [Cl-].C[N+](C)(C)CCOC(=O)C=C FZGFBJMPSHGTRQ-UHFFFAOYSA-M 0.000 description 4
- RSWGJHLUYNHPMX-UHFFFAOYSA-N Abietic-Saeure Natural products C12CCC(C(C)C)=CC2=CCC2C1(C)CCCC2(C)C(O)=O RSWGJHLUYNHPMX-UHFFFAOYSA-N 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 3
- 239000005995 Aluminium silicate Substances 0.000 description 3
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 3
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 3
- KHPCPRHQVVSZAH-HUOMCSJISA-N Rosin Natural products O(C/C=C/c1ccccc1)[C@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@@H](CO)O1 KHPCPRHQVVSZAH-HUOMCSJISA-N 0.000 description 3
- 239000004115 Sodium Silicate Substances 0.000 description 3
- 230000000996 additive effect Effects 0.000 description 3
- 235000012211 aluminium silicate Nutrition 0.000 description 3
- 229910001424 calcium ion Inorganic materials 0.000 description 3
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 3
- 239000000292 calcium oxide Substances 0.000 description 3
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 3
- 239000004927 clay Substances 0.000 description 3
- 229910052570 clay Inorganic materials 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 239000002270 dispersing agent Substances 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- 239000010419 fine particle Substances 0.000 description 3
- 238000005469 granulation Methods 0.000 description 3
- 230000003179 granulation Effects 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 235000021388 linseed oil Nutrition 0.000 description 3
- 239000000944 linseed oil Substances 0.000 description 3
- 239000011259 mixed solution Substances 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 239000010893 paper waste Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229920002401 polyacrylamide Polymers 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 3
- 235000012239 silicon dioxide Nutrition 0.000 description 3
- 229910052911 sodium silicate Inorganic materials 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- KHPCPRHQVVSZAH-UHFFFAOYSA-N trans-cinnamyl beta-D-glucopyranoside Natural products OC1C(O)C(O)C(CO)OC1OCC=CC1=CC=CC=C1 KHPCPRHQVVSZAH-UHFFFAOYSA-N 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 229920000881 Modified starch Polymers 0.000 description 2
- 239000004368 Modified starch Substances 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 2
- 239000004826 Synthetic adhesive Substances 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 150000001450 anions Chemical class 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 159000000007 calcium salts Chemical class 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 2
- 235000010980 cellulose Nutrition 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000000921 elemental analysis Methods 0.000 description 2
- 239000003623 enhancer Substances 0.000 description 2
- 230000003311 flocculating effect Effects 0.000 description 2
- 238000005227 gel permeation chromatography Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000004898 kneading Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000004513 sizing Methods 0.000 description 2
- GCLGEJMYGQKIIW-UHFFFAOYSA-H sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 description 2
- 235000019982 sodium hexametaphosphate Nutrition 0.000 description 2
- 229920003048 styrene butadiene rubber Polymers 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 2
- 239000003981 vehicle Substances 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- PQUXFUBNSYCQAL-UHFFFAOYSA-N 1-(2,3-difluorophenyl)ethanone Chemical compound CC(=O)C1=CC=CC(F)=C1F PQUXFUBNSYCQAL-UHFFFAOYSA-N 0.000 description 1
- HGUFODBRKLSHSI-UHFFFAOYSA-N 2,3,7,8-tetrachloro-dibenzo-p-dioxin Chemical compound O1C2=CC(Cl)=C(Cl)C=C2OC2=C1C=C(Cl)C(Cl)=C2 HGUFODBRKLSHSI-UHFFFAOYSA-N 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- 125000000954 2-hydroxyethyl group Chemical group [H]C([*])([H])C([H])([H])O[H] 0.000 description 1
- FVPMLCUKLBYBSV-UHFFFAOYSA-M 2-hydroxypropyl-dimethyl-(prop-2-enoyloxymethyl)azanium;chloride Chemical compound [Cl-].CC(O)C[N+](C)(C)COC(=O)C=C FVPMLCUKLBYBSV-UHFFFAOYSA-M 0.000 description 1
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 229920001661 Chitosan Polymers 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- WHNWPMSKXPGLAX-UHFFFAOYSA-N N-Vinyl-2-pyrrolidone Chemical compound C=CN1CCCC1=O WHNWPMSKXPGLAX-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- 229920002873 Polyethylenimine Polymers 0.000 description 1
- 239000002174 Styrene-butadiene Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229920001938 Vegetable gum Polymers 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 125000005396 acrylic acid ester group Chemical group 0.000 description 1
- 125000002947 alkylene group Chemical group 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 229920006318 anionic polymer Polymers 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 238000005282 brightening Methods 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- PASHVRUKOFIRIK-UHFFFAOYSA-L calcium sulfate dihydrate Chemical compound O.O.[Ca+2].[O-]S([O-])(=O)=O PASHVRUKOFIRIK-UHFFFAOYSA-L 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000010000 carbonizing Methods 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 229920006319 cationized starch Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000007334 copolymerization reaction Methods 0.000 description 1
- 238000005536 corrosion prevention Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000006114 decarboxylation reaction Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- GQOKIYDTHHZSCJ-UHFFFAOYSA-M dimethyl-bis(prop-2-enyl)azanium;chloride Chemical compound [Cl-].C=CC[N+](C)(C)CC=C GQOKIYDTHHZSCJ-UHFFFAOYSA-M 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000005038 ethylene vinyl acetate Substances 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000011361 granulated particle Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 125000004356 hydroxy functional group Chemical group O* 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229920003145 methacrylic acid copolymer Polymers 0.000 description 1
- 125000005397 methacrylic acid ester group Chemical group 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 235000019426 modified starch Nutrition 0.000 description 1
- 239000003607 modifier Substances 0.000 description 1
- 229940088644 n,n-dimethylacrylamide Drugs 0.000 description 1
- YLGYACDQVQQZSW-UHFFFAOYSA-N n,n-dimethylprop-2-enamide Chemical compound CN(C)C(=O)C=C YLGYACDQVQQZSW-UHFFFAOYSA-N 0.000 description 1
- OMNKZBIFPJNNIO-UHFFFAOYSA-N n-(2-methyl-4-oxopentan-2-yl)prop-2-enamide Chemical compound CC(=O)CC(C)(C)NC(=O)C=C OMNKZBIFPJNNIO-UHFFFAOYSA-N 0.000 description 1
- RQAKESSLMFZVMC-UHFFFAOYSA-N n-ethenylacetamide Chemical compound CC(=O)NC=C RQAKESSLMFZVMC-UHFFFAOYSA-N 0.000 description 1
- ZQXSMRAEXCEDJD-UHFFFAOYSA-N n-ethenylformamide Chemical compound C=CNC=O ZQXSMRAEXCEDJD-UHFFFAOYSA-N 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 238000007645 offset printing Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001254 oxidized starch Substances 0.000 description 1
- 235000013808 oxidized starch Nutrition 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 229920001495 poly(sodium acrylate) polymer Polymers 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000013055 pulp slurry Substances 0.000 description 1
- 150000003242 quaternary ammonium salts Chemical class 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 239000012488 sample solution Substances 0.000 description 1
- 238000000790 scattering method Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 229940047670 sodium acrylate Drugs 0.000 description 1
- NNMHYFLPFNGQFZ-UHFFFAOYSA-M sodium polyacrylate Chemical compound [Na+].[O-]C(=O)C=C NNMHYFLPFNGQFZ-UHFFFAOYSA-M 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 229940014800 succinic anhydride Drugs 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- OEIXGLMQZVLOQX-UHFFFAOYSA-N trimethyl-[3-(prop-2-enoylamino)propyl]azanium;chloride Chemical compound [Cl-].C[N+](C)(C)CCCNC(=O)C=C OEIXGLMQZVLOQX-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Paper (AREA)
Description
本発明は、再生粒子と二酸化チタン粒子とを含む複合粒子、複合粒子内添紙及び塗工紙に関する。 The present invention relates to composite particles containing regenerated particles and titanium dioxide particles, composite particle-added paper, and coated paper.
紙には、不透明度、白色度、印刷適性などを改善するために、これらの各機能向上に適した様々な填料が内添されている。上記填料としては、二酸化チタン、炭酸カルシウム、カオリン、タルク、水和ケイ酸（ホワイトカーボン）、尿素−ホルマリンポリマー微粒子などが用いられている。これらの中でも、二酸化チタンは屈折率が高く、光散乱能に優れるため、不透明度の向上には有効ではある。しかしながら、この二酸化チタン粒子は、高価であり、吸油能が小さく、加えて粒子径が小さいことに起因して抄紙の際の歩留まりが低いという不都合を有している。 In order to improve opacity, whiteness, printability, and the like, various fillers suitable for improving these functions are internally added to the paper. As the filler, titanium dioxide, calcium carbonate, kaolin, talc, hydrated silicic acid (white carbon), urea-formalin polymer fine particles and the like are used. Among these, titanium dioxide is effective in improving opacity because it has a high refractive index and excellent light scattering ability. However, the titanium dioxide particles are expensive, have a low oil absorption capacity, and have a disadvantage that the yield during papermaking is low due to the small particle diameter.
このような中、填料としての二酸化チタン粒子の歩留まりを向上させるべく、各種方法が提案されている。この方法としては、炭酸カルシウム粒子と酸化チタン粒子とを特定の凝集剤（カチオン性ポリマー、両性ポリマー、アクリル酸モノマー等）を用いて凝集させて凝集粒子を得る方法（特開２００４−１８３３６号公報及び特開平６−９３２０４号公報参照）が挙げられる。しかし、このような２種の粒子を凝集させる方法によれば、凝集剤による炭酸カルシウム粒子と酸化チタン粒子との結合は強いものではないため、抄紙の際にこの凝集状態が維持されないこと等により、十分な歩留まり向上効果を得ることができず、その結果、得られる紙の不透明度を効果的に向上させることができない。 Under such circumstances, various methods have been proposed to improve the yield of titanium dioxide particles as a filler. As this method, calcium carbonate particles and titanium oxide particles are aggregated using a specific aggregating agent (cationic polymer, amphoteric polymer, acrylic acid monomer, etc.) to obtain aggregated particles (Japanese Patent Application Laid-Open No. 2004-18336). And JP-A-6-93204). However, according to such a method of aggregating the two kinds of particles, since the binding between the calcium carbonate particles and the titanium oxide particles by the aggregating agent is not strong, this aggregation state is not maintained during papermaking. A sufficient yield improvement effect cannot be obtained, and as a result, the opacity of the obtained paper cannot be effectively improved.
一方、製紙工場の各種工程から排出される製紙スラッジ中の無機物を、いわゆる再生粒子として、製紙用填料等に再利用することが、製紙業界において環境問題に関わる重要な課題となっている。このような再生粒子を製造する方法としては、製紙スラッジを主原料とし、脱水、熱処理及び粉砕工程をこの順に経るものが一般的である。このような再生粒子は、様々な改良が行われているが、原料が廃棄物であるが故に粒径をはじめとした品質が一定ではなく、白色度も十分ではない。 On the other hand, the reuse of inorganic substances in paper sludge discharged from various processes in a paper mill as so-called recycled particles for paper making fillers has become an important issue related to environmental problems in the paper industry. As a method for producing such regenerated particles, paper sludge is used as a main raw material, and dehydration, heat treatment and pulverization steps are generally performed in this order. Such regenerated particles have been improved in various ways, but because the raw material is waste, the quality including the particle size is not constant, and the whiteness is not sufficient.
そこで、再生粒子等の填料の品質を向上させる技術として、粒子にシリカを被覆させる複合化が試みられている（特開２００８−８１３９０号公報及び特開２００３−４９３８９号公報参照）。このように再生粒子にシリカを被覆させることで、歩留まり及び白色度の向上は見られるものの、再生粒子を他の填料と同様の品質とするためには改善の余地がある。 Thus, as a technique for improving the quality of fillers such as regenerated particles, attempts have been made to combine the particles with silica (see Japanese Patent Application Laid-Open Nos. 2008-81390 and 2003-49389). By covering the regenerated particles with silica in this manner, the yield and whiteness are improved, but there is room for improvement in order to make the regenerated particles have the same quality as other fillers.
本発明は、上述の事情に基づいてなされたものであり、再生粒子及び二酸化チタン粒子を用い、高い歩留まり性、不透明度向上能及び白色度を有する複合粒子、並びにこの複合粒子を用い、かつ優れた不透明度等を有する複合粒子内添紙及び塗工紙を提供することを目的とする。 The present invention has been made based on the above-mentioned circumstances, and uses regenerated particles and titanium dioxide particles, composite particles having high yield, opacity improving ability and whiteness, and using these composite particles, and excellent Another object of the present invention is to provide a composite particle internal paper and coated paper having high opacity and the like.
上記課題を解決するためになされた発明は、
製紙スラッジを主原料とし、脱水、熱処理及び粉砕工程を経て得られた再生粒子と、
二酸化チタン粒子と
が凝集剤にて凝集されてなる複合粒子である。
The invention made to solve the above problems is
Paper sludge as the main raw material, regenerated particles obtained through dehydration, heat treatment and pulverization process,
It is a composite particle formed by agglomerating titanium dioxide particles with a flocculant.
当該複合粒子は、比較的粒径の大きい再生粒子と二酸化チタン粒子とが凝集されてなるため、再生粒子の表面を覆うように二酸化チタン粒子が凝集した状態となっている。従って、当該複合粒子によれば、二酸化チタン粒子を用いているにもかかわらず粒径が比較的大きく、優れた歩留まり性及び不透明度向上能を発揮することができる。特に、当該複合粒子においては、単なる凝集剤による凝集効果のみならず、粒径の小さい二酸化チタン粒子の一部が凝集の際に多孔質状の再生粒子の孔部分（凹部）に侵入して固着することなどにより強固な凝集状態が形成されている。このため、当該再生粒子によれば、抄紙等の際にもこの凝集状態が維持され、優れた歩留まり性を発揮することができる。また、当該複合粒子は、白色度が高い二酸化チタン粒子が再生粒子を覆う状態となっているため、再生粒子を用いているにもかかわらず白色度が高い。 The composite particles are formed by agglomerating regenerated particles and titanium dioxide particles having a relatively large particle diameter, and thus the titanium dioxide particles are in an aggregated state so as to cover the surface of the regenerated particles. Therefore, according to the composite particle, the particle diameter is relatively large despite using titanium dioxide particles, and excellent yield and opacity improving ability can be exhibited. In particular, in the composite particles, not only a flocculating effect by a flocculating agent, but also a part of titanium dioxide particles having a small particle size penetrates into the pores (recesses) of the porous regenerated particles during aggregation. By doing so, a strong aggregated state is formed. For this reason, according to the regenerated particles, this agglomerated state is maintained even during papermaking and the like, and an excellent yield can be exhibited. In addition, since the composite particles are in a state in which the titanium dioxide particles having high whiteness cover the regenerated particles, the whiteness is high even though the regenerated particles are used.
当該複合粒子の表面の少なくとも一部がシリカで被覆されているとよい。当該複合粒子によれば、このように表面の少なくとも一部がシリカで被覆されているため、上記二種類の粒子がさらに強固に固定され、抄紙等の工程においても、この凝集状態をより確実に維持することができ、歩留まり性をより高めることができる。また、当該複合粒子は、表面の少なくとも一部を被覆するこの多孔質状のシリカの優れた吸油能により、高い吸油度を発揮することができ、印刷不透明度を高めることができる。 It is preferable that at least a part of the surface of the composite particle is coated with silica. According to the composite particles, since at least a part of the surface is coated with silica as described above, the two types of particles are more firmly fixed, and this aggregation state can be more reliably ensured even in the papermaking process. This can be maintained, and the yield can be further improved. In addition, the composite particles can exhibit a high oil absorption by the excellent oil absorption ability of the porous silica covering at least a part of the surface, and the printing opacity can be increased.
上記シリカの被覆率が５質量％以上３０質量％以下であるとよい。当該複合粒子によれば、シリカ被覆率を上記範囲とすることで、抄紙の際等においても二種類の粒子の凝集状態を十分に維持することができ、その結果、歩留まり性をより高めることができることに加え、シリカと他の粒子とのバランスにより優れた白紙不透明度と印刷不透明度との両立を図ることができる。 The silica coverage is preferably 5% by mass or more and 30% by mass or less. According to the composite particles, by setting the silica coverage within the above range, the aggregation state of the two types of particles can be sufficiently maintained even during papermaking, and as a result, the yield can be further improved. In addition to being able to achieve this, it is possible to achieve both excellent white paper opacity and printing opacity due to the balance between silica and other particles.
当該複合粒子の平均粒子径が２μｍ以上１５μｍ以下であるとよい。当該複合粒子は、上記範囲の平均粒子径を有することにより、填料として用いた際、紙力の低下を抑えつつより優れた歩留まり性を発揮することができる。 The composite particles preferably have an average particle size of 2 μm or more and 15 μm or less. When the composite particles have an average particle diameter in the above range, when used as a filler, the composite particles can exhibit better yield while suppressing a decrease in paper strength.
上記再生粒子の平均粒子径（一次粒子径）が１μｍ以上１０μｍ以下であり、上記二酸化チタン粒子の平均粒子径（一次粒子径）が０．２μｍ以上１μｍ以下であるとよい。当該複合粒子によれば、上記範囲の粒径を有する二種類の粒子を用いることで、上述した比較的粒径の大きい再生粒子を核として、この表面を覆うように粒径の小さい複数の二酸化チタン粒子が凝集した状態を形成しやすい。従って、当該複合粒子は、二酸化チタン粒子の優れた光散乱能を十分に発揮させ、不透明度及び白色度を共にさらに高めることができる。 The regenerated particles may have an average particle size (primary particle size) of 1 μm or more and 10 μm or less, and the titanium dioxide particles may have an average particle size (primary particle size) of 0.2 μm or more and 1 μm or less. According to the composite particle, by using two types of particles having a particle size in the above range, the above-mentioned regenerated particles having a relatively large particle size are used as nuclei, and a plurality of small dioxide particles having a small particle size so as to cover the surface. It is easy to form an aggregated state of titanium particles. Therefore, the composite particles can sufficiently exhibit the excellent light scattering ability of the titanium dioxide particles, and can further increase both opacity and whiteness.
本発明の複合粒子内添紙は、上記複合粒子が内添されている。当該複合粒子内添紙によれば、上記性能を有する複合粒子が内添されているため、この填料としての複合粒子の歩留まり性が高く、白紙不透明度や印刷不透明度を高めることができる。 The composite particle internal paper of the present invention contains the above composite particles. According to the composite particle-added paper, since composite particles having the above performance are internally added, the yield of the composite particles as the filler is high, and the white paper opacity and the printing opacity can be increased.
本発明の塗工紙は、基紙と、この基紙の少なくとも一方の面に形成される１又は複数層の塗工層とを有する塗工紙であって、上記塗工層が上記複合粒子を含有することを特徴とする。当該塗工紙は、上記複合粒子を顔料として塗工層に含有しているため、白紙不透明度及び印刷後不透明度に優れる。 The coated paper of the present invention is a coated paper having a base paper and one or more coating layers formed on at least one surface of the base paper, wherein the coating layer is the composite particle. It is characterized by containing. Since the coated paper contains the composite particles as a pigment in the coating layer, the coated paper is excellent in blank paper opacity and post-printing opacity.
ここで、平均粒子径とは、レーザー回析散乱法により測定された粒度分布における体積平均粒径（Ｄ５０）をいう。 Here, the average particle diameter refers to a volume average particle diameter in the measured particle size distribution by laser diffraction scattering method (D 50).
以上説明したように、本発明の複合粒子は、高い歩留まり性、不透明度向上能及び白色度を有する。従って、この複合粒子を用いた複合粒子内添紙及び塗工紙は優れた不透明度等を発揮することができる。 As described above, the composite particles of the present invention have high yield, opacity improving ability, and whiteness. Therefore, composite particle-added paper and coated paper using this composite particle can exhibit excellent opacity and the like.
以下、本発明の複合粒子、複合粒子内添紙及び塗工紙の実施の形態について、順に詳説する。 Hereinafter, embodiments of the composite particles, composite particle-added paper, and coated paper of the present invention will be described in detail.
＜複合粒子＞
本発明の複合粒子は、製紙スラッジを主原料とし、脱水、熱処理及び粉砕工程を経て得られた再生粒子と、二酸化チタン粒子とが凝集剤にて凝集されてなる複合粒子である。
<Composite particle>
The composite particle of the present invention is a composite particle obtained by agglomerating a regenerated particle obtained from papermaking sludge as a main raw material through a dehydration, heat treatment and pulverization step and a titanium dioxide particle with a flocculant.
当該複合粒子は、比較的粒径の大きい再生粒子と二酸化チタン粒子とが凝集されてなるため、再生粒子の表面を覆うように二酸化チタン粒子が凝集した状態となっている。従って、当該複合粒子によれば、二酸化チタン粒子を用いているにもかかわらず粒径が比較的大きく、優れた歩留まり性及び不透明度向上能を発揮することができる。特に、当該複合粒子においては、単なる凝集剤による凝集効果のみならず、粒径の小さい二酸化チタン粒子の一部が、凝集の際に多孔質状の再生粒子の孔部分に固着することなどにより強固な凝集状態が形成されている。このため、当該再生粒子によれば、抄紙等の際にもこの凝集状態が維持され、凝集状態が崩れにくいため優れた歩留まり性を発揮することができる。また、当該複合粒子は、白色度が高い二酸化チタン粒子が再生粒子を覆う状態となっているため、再生粒子を用いているにもかかわらず白色度が高い。 The composite particles are formed by agglomerating regenerated particles and titanium dioxide particles having a relatively large particle diameter, and thus the titanium dioxide particles are in an aggregated state so as to cover the surface of the regenerated particles. Therefore, according to the composite particle, the particle diameter is relatively large despite using titanium dioxide particles, and excellent yield and opacity improving ability can be exhibited. In particular, in the composite particles, not only the flocculating effect by the flocculating agent, but also a part of the titanium dioxide particles having a small particle size is firmly adhered to the pores of the porous regenerated particles during the aggregation. An agglomerated state is formed. For this reason, according to the regenerated particles, this agglomerated state is maintained even during papermaking, and the agglomerated state is not easily broken, so that an excellent yield can be exhibited. In addition, since the composite particles are in a state in which the titanium dioxide particles having high whiteness cover the regenerated particles, the whiteness is high even though the regenerated particles are used.
当該複合粒子の平均粒子径としては、２μｍ以上１５μｍ以下が好ましく、４μｍ以上１０μｍ以下がさらに好ましい。当該複合粒子は、上記範囲の平均粒子径を有することにより、填料として用いた際、紙力の低下を抑えつつ、より優れた歩留まり性能を発揮することができる。また、塗工液中に含有されて顔料として用いる際などの均一分散性を向上させることができる。従って、填料又は顔料として用いた際の不透明度等を効率的に高めることができる。 The average particle size of the composite particles is preferably 2 μm or more and 15 μm or less, and more preferably 4 μm or more and 10 μm or less. Since the composite particles have an average particle diameter in the above range, when used as a filler, the composite particles can exhibit better yield performance while suppressing a decrease in paper strength. Moreover, the uniform dispersibility, such as when contained in a coating liquid and used as a pigment, can be improved. Therefore, the opacity when used as a filler or pigment can be efficiently increased.
当該複合粒子の平均粒径が上記下限未満の場合は、填料として用いたときに歩留まり性が十分に向上しないおそれがあり、また、不透明度向上能も十分ではない。一方、この平均粒子径が上記上限を超えると填料として用いた場合、パルプ繊維間の強度を低下させる結果、紙力が低下する場合があり、また、粒径が大きいことで、スラリー又は塗工液中での均一分散性が低下し、不透明度及び印刷後不透明度が低下するおそれがある。 When the average particle size of the composite particles is less than the above lower limit, the yield may not be sufficiently improved when used as a filler, and the opacity improving ability is not sufficient. On the other hand, when this average particle diameter exceeds the upper limit, when used as a filler, as a result of reducing the strength between the pulp fibers, the paper strength may be reduced, and because the particle size is large, slurry or coating Uniform dispersibility in the liquid may be reduced, and opacity and opacity after printing may be reduced.
上記再生粒子と二酸化チタン粒子との含有比（質量比）としては、３０：７０〜９０：１０が好ましく、５０：５０〜９０：１０がさらに好ましい。両粒子の含有比をこのような範囲とすることで、再生粒子を核として、この表面に粒径の小さい二酸化チタン粒子を効率的に凝集した状態とすることができる。従って、当該複合粒子によれば、二酸化チタン粒子の優れた光散乱能を活かしつつ、凝集体として粒径を大きくすることで、より優れた歩留まり性を発揮することができる。また、当該複合粒子によれば、白色度の高くない再生粒子を二酸化チタンで効率的に被覆することで、白色度をより高めることができる。 The content ratio (mass ratio) of the regenerated particles and titanium dioxide particles is preferably 30:70 to 90:10, and more preferably 50:50 to 90:10. By setting the content ratio of both particles in such a range, titanium dioxide particles having a small particle diameter can be efficiently aggregated on the surface with the regenerated particles as nuclei. Therefore, according to the composite particle, it is possible to exhibit a better yield by increasing the particle size as an aggregate while utilizing the excellent light scattering ability of the titanium dioxide particles. Moreover, according to the said composite particle, whiteness can be raised more by efficiently coat | covering the reproduction | regeneration particle | grains which are not high whiteness with titanium dioxide.
＜再生粒子＞
上記再生粒子は、製紙スラッジを主原料とし、脱水、熱処理及び粉砕工程を経て得られたものである。このような工程を経て得られた再生粒子は、過燃焼が抑えられており、スラリー化の際の増粘を抑制することができる。また、上記再生粒子は、不定形状かつ多孔質形状であるため、上述のように凝集の際、比較的粒径の小さい二酸化チタン粒子を孔部分等に固定することが可能である。なお、この再生粒子の好ましい製造方法については、後に詳述する。
<Regenerated particles>
The regenerated particles are obtained by using papermaking sludge as a main raw material, followed by dehydration, heat treatment and pulverization steps. The regenerated particles obtained through such steps are suppressed from over-combustion and can suppress thickening during slurrying. Further, since the regenerated particles have an indefinite shape and a porous shape, it is possible to fix titanium dioxide particles having a relatively small particle size to the pores or the like during aggregation as described above. A preferable method for producing the regenerated particles will be described in detail later.
上記再生粒子の平均粒子径（一次粒子径）としては、１μｍ以上１０μｍ以下が好ましく、２μｍ以上５μｍ以下がさらに好ましい。再生粒子の平均粒子径を上記範囲とすることで、粒径の小さい再生粒子同士の凝集が進み、一方、粒径の元々大きい粒子は凝集が進行しにくい効果が得られ、複合粒子の粒径を所望する範囲に制御しやすくなり、抄紙の際の歩留まりをより高めることができる。 The average particle size (primary particle size) of the regenerated particles is preferably 1 μm or more and 10 μm or less, and more preferably 2 μm or more and 5 μm or less. By setting the average particle diameter of the regenerated particles in the above range, aggregation of the regenerated particles having a small particle diameter progresses, whereas the effect of the aggregation of particles having a large particle diameter from the tendency of the agglomeration to hardly proceed is obtained. Can be easily controlled within a desired range, and the yield in papermaking can be further increased.
再生粒子の平均粒子径が上記下限未満の場合は、凝集剤によっても十分な粒径にまで凝集が進まず、歩留まりが十分に高まらない場合がある。逆に、再生粒子の平均粒子径が上記上限を超える場合は、得られる凝集体の粒径が大きくなりすぎる場合があり、この結果紙力が低下するおそれがある。 When the average particle diameter of the regenerated particles is less than the above lower limit, aggregation may not proceed to a sufficient particle size even with a flocculant, and the yield may not be sufficiently increased. Conversely, when the average particle size of the regenerated particles exceeds the above upper limit, the particle size of the resulting aggregate may be too large, and as a result, the paper strength may be reduced.
＜二酸化チタン粒子＞
二酸化チタン粒子は、屈折率が高く、光散乱能に優れるため、白紙不透明度を高めることができる。
<Titanium dioxide particles>
Titanium dioxide particles have a high refractive index and an excellent light scattering ability, and therefore can increase the white paper opacity.
当該複合粒子に用いられる二酸化チタン粒子は、平均粒子径（一次粒子径）が０．２μｍ以上１μｍ以下であることが好ましく、０．３μｍ以上０．８μｍ以下がさらに好ましい。また、上記再生粒子の平均粒子径に対する、上記二酸化チタン粒子の平均粒子径としては、０．０５倍以上０．４倍以下であるとよい。 The titanium dioxide particles used for the composite particles preferably have an average particle size (primary particle size) of 0.2 μm or more and 1 μm or less, and more preferably 0.3 μm or more and 0.8 μm or less. The average particle size of the titanium dioxide particles relative to the average particle size of the regenerated particles is preferably 0.05 times or more and 0.4 times or less.
上記二酸化チタン粒子の平均粒子径をこのような範囲とすることで、上述した比較的粒径の大きい再生粒子を核として、この表面を覆うように粒径の小さい複数の二酸化チタン粒子が凝集した状態を形成しやすい。従って、当該複合粒子は、二酸化チタン粒子の優れた光散乱能を十分に発揮させて、不透明度及び白色度を共にさらに高めることができる。二酸化チタン粒子の平均粒子径が上記下限未満の場合は、凝集が進行しにくく、十分な粒径の複合粒子を得られにくくなる場合がある。逆に、二酸化チタン粒子の平均粒子径が上記上限を超えると、再生粒子の孔部分（凹部）に侵入しにくくなるなどにより、凝集性が低く、歩留まりが低下するおそれがある。 By setting the average particle diameter of the titanium dioxide particles in such a range, a plurality of titanium dioxide particles having a small particle diameter are aggregated so as to cover the surface with the regenerated particles having a relatively large particle diameter as a core. Easy to form a state. Therefore, the composite particles can sufficiently enhance both the opacity and the whiteness by sufficiently exhibiting the excellent light scattering ability of the titanium dioxide particles. When the average particle diameter of the titanium dioxide particles is less than the above lower limit, aggregation is unlikely to proceed and it may be difficult to obtain composite particles having a sufficient particle diameter. On the other hand, when the average particle diameter of the titanium dioxide particles exceeds the above upper limit, the cohesiveness is low and the yield may be lowered due to difficulty in entering the pores (recessed parts) of the regenerated particles.
上記二酸化チタン粒子としては、特に限定されず、製紙用として公知のものを用いることができる。この二酸化チタン粒子の結晶形態としては、アナターゼ型、ルチル型、ブルカイト型等のいずれも使用することができるが、ルチル型又はアナターゼ型を用いることが好ましい。 The titanium dioxide particles are not particularly limited, and those known for papermaking can be used. As the crystal form of the titanium dioxide particles, any of anatase type, rutile type, brookite type and the like can be used, but it is preferable to use rutile type or anatase type.
＜凝集剤＞
凝集剤は、再生粒子と二酸化チタン粒子とを凝集させる。この凝集剤としては、その高分子鎖により複数の粒子を絡み取り凝集させることができるものであれば特に限定されずカチオン性高分子、アニオン性高分子、非イオン性高分子等の高分子化合物を用いることができる。但し、本発明者等の知見によると、再生粒子と二酸化チタン粒子とを含むスラリーを用い、再生粒子を核としてその表面に二酸化チタン粒子を被覆させるには、カチオン性高分子を用いることが好ましく、カチオン性合成高分子を用いることがさらに好ましい。凝集剤としてカチオン性高分子を用いることで、負に帯電している再生粒子表面にこの凝集剤が優先的に付着し、その表面に二酸化チタン粒子を効果的に付着させることができ、一方、カチオン化された比較的大きい再生粒子同士の凝集を抑え、得られる複合粒子が大型化することを抑えることができる。また、カチオン性合成高分子を用いることで、この凝集剤のカチオン電荷密度及び好適な分子量を容易に調整することができる。
<Flocculant>
The flocculant aggregates the regenerated particles and the titanium dioxide particles. The aggregating agent is not particularly limited as long as it can entangle and aggregate a plurality of particles by the polymer chain, and a polymer compound such as a cationic polymer, an anionic polymer, or a nonionic polymer. Can be used. However, according to the knowledge of the present inventors, it is preferable to use a cationic polymer in order to use a slurry containing regenerated particles and titanium dioxide particles and coat the surface of the regenerated particles with titanium dioxide particles as a core. It is more preferable to use a cationic synthetic polymer. By using a cationic polymer as the aggregating agent, the aggregating agent is preferentially attached to the negatively charged regenerated particle surface, and the titanium dioxide particles can be effectively attached to the surface, Aggregation of relatively large cationized regenerated particles can be suppressed, and the resulting composite particles can be prevented from becoming large. Moreover, the cationic charge density and suitable molecular weight of this flocculant can be easily adjusted by using a cationic synthetic polymer.
この凝集剤の質量平均分子量の下限としては、粒径の小さい粒子同士は凝集が進み、一方、粒径の元々大きい粒子は凝集が進行しにくい効果、すなわち粒度分布を狭くする効果を十分に発現させため、４００万が好ましく、６００万がさらに好ましく、７００万が特に好ましい。一方、この質量平均分子量の上限としては、２，０００万が好ましく、１，２００万がさらに好ましく、１，０００万が特に好ましい。凝集剤の分子量を上記範囲とすることで、粒径の小さい再生粒子同士は凝集が進み、一方、粒径の元々大きい再生粒子同士は凝集が進行しにくい凝集性を発揮することができる。特に、上述のような平均粒子径を有する再生粒子に対しては、このような範囲の分子量を有する凝集剤を用いることで、所望する粒子径を有する複合粒子（凝集体）を効率的に得ることができる。なお、質量平均分子量はゲル浸透クロマトグラフィー法（ＧＰＣ法）を用いて測定した数値である。 As a lower limit of the mass average molecular weight of the flocculant, particles having a small particle diameter progress in aggregation, while particles having an originally large particle diameter sufficiently exhibit the effect that aggregation does not proceed easily, that is, the effect of narrowing the particle size distribution. Therefore, 4 million is preferable, 6 million is more preferable, and 7 million is particularly preferable. On the other hand, the upper limit of the mass average molecular weight is preferably 20 million, more preferably 12 million, and particularly preferably 10 million. By setting the molecular weight of the aggregating agent within the above range, regenerated particles having a small particle diameter can be aggregated, while regenerated particles having an originally large particle diameter can exhibit cohesiveness in which aggregation does not easily proceed. In particular, for regenerated particles having an average particle size as described above, a composite particle (aggregate) having a desired particle size can be efficiently obtained by using an aggregating agent having a molecular weight in such a range. be able to. The mass average molecular weight is a numerical value measured using a gel permeation chromatography method (GPC method).
凝集剤の質量平均分子量が上記下限未満の場合は、十分な凝集能を発揮することができず、粒子の凝集が進まないため、歩留まりの向上が発揮されないおそれがある。逆に、この平均分子量が上記上限を超える場合は、凝集能が強すぎて、偏凝集の発生や、スラリーの粘度が上昇して抄紙の作業性が低下したり、得られる紙の紙力が低下したりするおそれがある。 When the mass average molecular weight of the flocculant is less than the above lower limit, sufficient aggregating ability cannot be exhibited, and the particles are not agglomerated, so that the yield may not be improved. Conversely, if this average molecular weight exceeds the above upper limit, the agglomeration ability is too strong, the occurrence of partial agglomeration, the viscosity of the slurry is increased, the paper workability is reduced, the paper strength of the resulting paper is It may decrease.
また、凝集剤のカチオン電荷密度の上限としては、３０ｍｅｑ／ｇが好ましく、２０ｍｅｑ／ｇがさらに好ましく、１５ｍｅｑ／ｇが特に好ましい。一方、このカチオン電荷密度の下限としては、０．１ｍｅｑ／ｇが好ましく、１ｍｅｑ／ｇがさらに好ましく、２ｍｅｑ／ｇが特に好ましい。凝集剤のカチオン電荷密度を上記範囲とすることで、再生粒子がもつブロードな粒度分布において、粒径の小さい粒子同士は凝集が進み、一方、粒径の元々大きい粒子は凝集が進行しにくい好適な凝集性を発揮することができる。なお、凝集剤として複数の成分を用いる場合は、その凝集剤全体としてのカチオン電荷密度をいう。 The upper limit of the cation charge density of the flocculant is preferably 30 meq / g, more preferably 20 meq / g, and particularly preferably 15 meq / g. On the other hand, the lower limit of the cation charge density is preferably 0.1 meq / g, more preferably 1 meq / g, and particularly preferably 2 meq / g. By setting the cation charge density of the aggregating agent in the above range, in the broad particle size distribution of the regenerated particles, the particles having a small particle diameter proceed to agglomerate, whereas the particles having an originally large particle diameter are less likely to proceed to agglomerate. Excellent cohesiveness can be exhibited. In addition, when using a some component as an aggregating agent, the cation charge density as the whole aggregating agent is said.
本発明において、上記カチオン電荷密度は以下の方法で測定した値である。試料をｐＨ４．０の水溶液に調整した後、流動電位法に基づく粒子荷電測定装置（Ｍｕｔｅｃｋ ＰＣＤ−０３）にて、１／１０００規定のポリビニル硫酸カリウム水溶液を用いた滴定によって、アニオン要求量を測定する。下記式（１）により試料１ｇあたりのカチオン電荷密度を計算する。
カチオン電荷密度＝Ａ／Ｂ ・・・（１）
Ａ：ｐＨ４．０に調整した凝集剤水溶液のアニオン要求量（μｅｑ／ｌ）
Ｂ：凝集剤水溶液の固形分濃度（ｇ／ｌ）
In the present invention, the cationic charge density is a value measured by the following method. After adjusting the sample to an aqueous solution of pH 4.0, the anion demand was measured by titration using a 1/1000 normal aqueous potassium potassium sulfate solution with a particle charge measuring device (Muteck PCD-03) based on the streaming potential method. To do. The cationic charge density per 1 g of sample is calculated by the following formula (1).
Cationic charge density = A / B (1)
A: Anion requirement (μeq / l) of the flocculant aqueous solution adjusted to pH 4.0
B: Solid content concentration of the flocculant aqueous solution (g / l)
凝集剤のカチオン電荷密度が上記上限を超えると、再生粒子に加えて、二酸化チタン粒子もがカチオン電荷を帯び、電荷による反発で凝集が生じにくくなる場合がある。逆に、凝集剤のカチオン電荷密度が上記下限未満の場合は、負に帯電している再生粒子（特に粒径の小さい再生粒子）を電気的に凝集させることができる効果を十分に発揮することができず、ブロードな粒度分布となる場合がある。 When the cation charge density of the flocculant exceeds the above upper limit, in addition to the regenerated particles, the titanium dioxide particles also have a cation charge, and aggregation may not easily occur due to repulsion due to the charge. Conversely, when the cation charge density of the flocculant is less than the above lower limit, the effect of being able to electrically agglomerate negatively charged regenerated particles (particularly regenerated particles having a small particle size) should be sufficiently exhibited. May not be possible, resulting in a broad particle size distribution.
凝集剤として好適に用いられることのできるカチオン性合成高分子としては、（メタ）アクリレート系カチオン性単量体の単独重合物又は非イオン性単量体との共重合物、ポリアクリルアミドのマンニッヒ変性物、ポリ（ジメチルジアリルアンモニウムクロライド）、ジアルキルアミン−エピクロルヒドリン縮合物、アルキレンジクロライド−ポリアルキレンポリアミン縮合物、ポリエチレンイミン、ジシアンジアミド−ホルマリン縮合物、ポリビニルアミジン、キトサン、ポリアルキレンポリアミンなどを挙げることができ、これらを１種又は２種以上を混合して用いることができる。 Cationic synthetic polymers that can be suitably used as flocculants include homopolymers of (meth) acrylate-based cationic monomers or copolymers with nonionic monomers, and Mannich modification of polyacrylamide. Products, poly (dimethyldiallylammonium chloride), dialkylamine-epichlorohydrin condensate, alkylene dichloride-polyalkylene polyamine condensate, polyethyleneimine, dicyandiamide-formalin condensate, polyvinylamidine, chitosan, polyalkylene polyamine, etc. These can be used alone or in combination of two or more.
これらの中でも、凝集性及びスラリーの増粘抑制性の点から、（メタ）アクリレート系カチオン性単量体と非イオン性単量体との共重合物が好ましく、（メタ）アクリレート系カチオン性単量体と非イオン性単量体との共重合物及びポリアルキレンポリアミンの混合物が特に好ましい。 Among these, a copolymer of a (meth) acrylate cationic monomer and a nonionic monomer is preferable from the viewpoint of aggregation and slurry thickening suppression, and a (meth) acrylate cationic monomer is preferable. A copolymer of a monomer and a nonionic monomer and a mixture of a polyalkylene polyamine are particularly preferred.
（メタ）アクリレート系カチオン性単量体としては、（メタ）アクリロイルオキシエチルトリメチルアンモニウムクロライド、（メタ）アクリロイルアミノプロピルトリメチルアンモニウムクロライド、（メタ）アクリロイルオキシ−２−ヒドロキシプロピルトリメチルアンモニウムクロライド等を挙げることができる。これらの（メタ）アクリレート系カチオン性単量体の中でも、再生粒子及び二酸化チタン粒子に対する凝集性及びスラリーの増粘抑制性の点から（メタ）アクリル系単量体を用いることが好ましく、（メタ）アクリロイルオキシエチルトリメチルアンモニウムクロライドが、より好ましく、アクリロイルオキシエチルトリメチルアンモニウムクロライドが特に好ましい。 Examples of (meth) acrylate-based cationic monomers include (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloylaminopropyltrimethylammonium chloride, (meth) acryloyloxy-2-hydroxypropyltrimethylammonium chloride, and the like. Can do. Among these (meth) acrylate cationic monomers, it is preferable to use a (meth) acrylic monomer from the viewpoints of agglomeration with respect to regenerated particles and titanium dioxide particles and suppression of thickening of the slurry. ) Acryloyloxyethyltrimethylammonium chloride is more preferred, and acryloyloxyethyltrimethylammonium chloride is particularly preferred.
（メタ）アクリレート系カチオン性単量体との共重合に用いられる非イオン性単量体としては、アクリルアミド、Ｎ−ビニルホルムアミド、Ｎ−ビニルアセトアミド、Ｎ−ビニルピロリドン、Ｎ、Ｎ−ジメチルアクリルアミド、アクリロニトリル、ジアセトンアクリルアミド、２−ヒドロキシエチル（メタ）アクリレ−トのなどを挙げることができる。これらの中でもアクリルアミドを用いることが、所望の分子量及び電荷密度を有するカチオン性合成高分子を得られやすい点から好ましい。 Nonionic monomers used for copolymerization with (meth) acrylate cationic monomers include acrylamide, N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, Examples thereof include acrylonitrile, diacetone acrylamide, and 2-hydroxyethyl (meth) acrylate. Among these, acrylamide is preferably used because it is easy to obtain a cationic synthetic polymer having a desired molecular weight and charge density.
＜シリカ＞
当該複合粒子においては、表面の少なくと一部がシリカで被覆されているとよい。このような複合粒子によれば、表面の少なくとも一部がシリカで被覆されているため、上記二種類の粒子がさらに強固に固定され、抄紙等の工程においても、この凝集状態をより確実に維持することができ、歩留まり性をより高めることができる。また、当該複合粒子は、表面の少なくとも一部を被覆するこの多孔質状のシリカの優れた吸油能により、高い吸油度を発揮することができ、印刷不透明度を高めることができる。
<Silica>
In the composite particles, at least a part of the surface is preferably coated with silica. According to such composite particles, since at least a part of the surface is coated with silica, the above two types of particles are more firmly fixed, and this agglomeration state is more reliably maintained even in processes such as papermaking. And the yield can be further improved. In addition, the composite particles can exhibit a high oil absorption by the excellent oil absorption ability of the porous silica covering at least a part of the surface, and the printing opacity can be increased.
上記シリカとしては、特に限定されず公知のものを用いることができる。なお、後述するように水溶液中でシリカを析出し被覆させることで、効率的に凝集体に被覆させることができ、かつ、多孔質状に被覆させることができるため優れた吸油能を発揮することができる。 The silica is not particularly limited, and a known silica can be used. As will be described later, by depositing and coating silica in an aqueous solution, it is possible to efficiently coat the aggregate and to exhibit a superior oil absorption ability because it can be coated in a porous state. Can do.
このシリカの被覆率としては、５質量％以上３０質量％以下が好ましく、５質量％以上２０質量％以下がさらに好ましい。シリカ被覆率をこのような範囲とすることで、抄紙の際等においても二種類の粒子の凝集状態を十分に維持することができ、その結果、歩留まりをより高めることができることに加え、シリカと他の粒子とのバランスにより優れた白紙不透明度と印刷不透明度との両立を図ることができる。なお、このシリカ被覆率は、粒子の元素分析を行い、含有する構成成分からクレー、炭酸カルシウム、タルク等の含有割合を推定し、シリカ被覆後のシリカ成分の含有率から算出することができる。また、シリカの被覆率とは、複合粒子全体の質量に対するシリカの質量の割合をいう。 The silica coverage is preferably 5% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less. By making the silica coverage in such a range, it is possible to sufficiently maintain the aggregation state of the two types of particles even during papermaking, and as a result, in addition to being able to further increase the yield, silica and It is possible to achieve both excellent white paper opacity and printing opacity due to the balance with other particles. This silica coverage can be calculated from the content of the silica component after silica coating by conducting elemental analysis of the particles, estimating the content ratio of clay, calcium carbonate, talc and the like from the constituent components contained. The silica coverage refers to the ratio of the mass of silica to the total mass of the composite particles.
シリカ被覆率が上記下限未満の場合は、このシリカが二種類の粒子のバインダーとして十分に機能せず、抄紙の際に凝集状態が分断し、歩留まりが向上しないおそれがある。また、シリカによる十分な吸油度の向上効果が発揮されない場合がある。逆に、シリカ被覆率が上記上限を超える場合は、シリカ被覆量が多くなりすぎるため、二酸化チタン粒子の光散乱機能が十分に発揮されず、白紙不透明度が低下するおそれがある。 When the silica coverage is less than the above lower limit, this silica does not sufficiently function as a binder for the two kinds of particles, and the agglomerated state is divided during papermaking, and the yield may not be improved. Moreover, the sufficient oil absorption improvement effect by silica may not be exhibited. On the other hand, when the silica coverage exceeds the above upper limit, the silica coating amount becomes too large, so that the light scattering function of the titanium dioxide particles is not sufficiently exhibited, and the blank paper opacity may be lowered.
＜用途、品質等＞
当該複合粒子は、製紙の際の内添填料または塗工用顔料として、単独で又は通常の炭酸カルシウム、カオリンクレー、タルク、二酸化チタン、サチンホワイト、プラスチックピグメント等の顔料と混合して好適に用いることができる。
<Application, quality, etc.>
The composite particles are suitably used alone or mixed with ordinary pigments such as calcium carbonate, kaolin clay, talc, titanium dioxide, satin white, and plastic pigment as an internal filler or coating pigment in papermaking. be able to.
当該複合粒子を内添填料や塗工用顔料として使用する場合、例えば、上記通常の内添用填料や塗工用顔料の合計量に対して、当該複合粒子を５〜１００質量％、好適には１０〜１００質量％添加して使用することができる。 When the composite particles are used as an internal additive or a coating pigment, for example, the composite particles are preferably contained in an amount of 5 to 100% by mass with respect to the total amount of the normal internal additive or coating pigment. Can be used by adding 10 to 100% by mass.
当該複合粒子は、上述のように高い白色度を有する。当該複合粒子の具体的な白色度としては、８０％以上が好ましく、８５％以上がさらに好ましい。なお、この白色度は、Ｔａｐｐｉ−５３４ｐｍ−７６法に準じて測定した値である。 The composite particles have high whiteness as described above. The specific whiteness of the composite particles is preferably 80% or more, and more preferably 85% or more. The whiteness is a value measured according to the Tappi-534 pm-76 method.
当該複合粒子の吸油度は、３０ｍＬ／１００ｇ以上１５０ｍＬ／１００ｇ以下、より好ましくは６０ｍＬ／１００ｇ以上１００ｍＬ／１００ｇ以下の範囲が好ましい。このような吸油度を有する複合粒子を内添填料として使用すると、紙層中においてこの複合粒子が紙層中に含浸されるインクのビヒクル分や有機溶剤等を吸収するため用紙の印刷不透明度が低下するのを抑制し、また、インクのビヒクル分や有機溶剤等を吸収することで、インク乾燥性やニジミの防止効果を顕著に発揮することができる。この吸油度が３０ｍＬ／１００ｇ未満の場合には上記の効果が十分でなく、複合粒子がインクの吸収・乾燥性を阻害する傾向が生じる場合が有る。また吸油度が１５０ｍＬ／１００ｇを超えると、インクの吸収性が高いためインクの沈みこみ、いわゆる発色性が劣る不都合が生じる場合がある。 The oil absorption of the composite particles is preferably 30 mL / 100 g or more and 150 mL / 100 g or less, more preferably 60 mL / 100 g or more and 100 mL / 100 g or less. When composite particles having such an oil absorption are used as an internal filler, the composite particles absorb ink vehicle or organic solvent impregnated in the paper layer in the paper layer, and the printing opacity of the paper is reduced. By suppressing the reduction and absorbing the ink vehicle, the organic solvent, and the like, the ink drying property and the effect of preventing blurring can be remarkably exhibited. When the oil absorption is less than 30 mL / 100 g, the above effect is not sufficient, and the composite particles may tend to inhibit the ink absorption and drying properties. On the other hand, if the oil absorption exceeds 150 mL / 100 g, there is a case where the ink sinks and the so-called color developability is inferior because the ink absorbability is high.
なお、当該複合粒子は製紙用以外に、例えばゴム、プラスチック、塗料、インキ等のフィラーなどとして用いることができる。当該複合粒子をフィラーとして用いることで高い白色度と隠蔽性を付与することができる。 The composite particles can be used as fillers for rubber, plastics, paints, inks, etc. in addition to papermaking. By using the composite particle as a filler, high whiteness and concealment can be imparted.
＜複合粒子の製造方法＞
当該複合粒子の製造方法としては特に限定されないが、例えば、
（１）再生粒子と二酸化チタン粒子とを凝集剤により凝集させる凝集工程、及び、必要に応じて
（２）上記凝集体表面の少なくとも一部にシリカを被覆させるシリカ被覆工程
を有する方法を挙げることができる。以下、各工程について順に詳説する。
<Method for producing composite particles>
Although it does not specifically limit as the manufacturing method of the said composite particle, For example,
(1) A method having an aggregating step of aggregating regenerated particles and titanium dioxide particles with an aggregating agent, and (2) a silica coating step of coating silica on at least a part of the agglomerate surface as necessary. Can do. Hereinafter, each step will be described in detail.
＜（１）凝集工程＞
この凝集工程は、例えば再生粒子と二酸化チタン粒子とを水中へ分散させた粒子スラリーへ、凝集剤を添加することによって行うことができる。両粒子の水中へ分散は、この２種の粒子を同時に水中へ分散させてもよいし、再生粒子を水中へ分散させた再生粒子スラリー中に二酸化チタン粒子を分散させてもよく、その逆であってもよい。
<(1) Aggregation step>
This aggregating step can be performed, for example, by adding an aggregating agent to a particle slurry in which regenerated particles and titanium dioxide particles are dispersed in water. The two particles may be dispersed in water by dispersing the two types of particles in water at the same time, or by dispersing titanium dioxide particles in a regenerated particle slurry in which regenerated particles are dispersed in water, and vice versa. There may be.
なお、凝集剤としてカチオン性凝集剤を用いる場合は、再生粒子と二酸化チタン粒子（又は二酸化チタン粒子を水中へ分散させた二酸化チタン粒子スラリー）を水中へ分散させた再生粒子と二酸化チタン粒子のスラリー中にカチオン性凝集剤を添加するとよい。この方法により、単独の粒子にカチオン性凝集剤を添加させた後工程で他の粒子を添加する手段と異なり、先の粒子にて凝集剤の効果が消費されことなくカチオン性凝集剤を用いる効果（負に帯電している再生粒子表面にカチオン性凝集剤が優先的に付着し、その表面に二酸化チタン粒子を効果的に付着させることができ、一方、カチオン化された比較的大きい再生粒子同士の凝集を抑え、得られる複合粒子が大型化することを抑えることができる効果）を十分に発揮させることができる。 When a cationic flocculant is used as the flocculant, a regenerated particle and titanium dioxide particle slurry in which regenerated particles and titanium dioxide particles (or titanium dioxide particle slurry in which titanium dioxide particles are dispersed in water) are dispersed in water. A cationic flocculant may be added therein. By this method, the effect of using the cationic flocculant without consuming the effect of the flocculant in the previous particle is different from the means of adding other particles in the subsequent step after adding the cationic flocculant to the single particle. (The cationic flocculant preferentially adheres to the surface of the negatively charged regenerative particles, and the titanium dioxide particles can effectively adhere to the surface, while the relatively large regenerated particles that are cationized The effect of suppressing the agglomeration and suppressing the resulting composite particles from becoming large) can be sufficiently exhibited.
粒子スラリーにおける両粒子（再生粒子と二酸化チタン粒子との合計）の固形分濃度としては、５質量％以上４０％質量以下が好ましく、１０質量％以上３５質量％以下がさらに好ましく、１５質量％以上２５質量％以下が特に好ましい。粒子スラリーの濃度を上記範囲とすることで、粒子の凝集性の効率化を図ることができる。 The solid content concentration of both particles (total of regenerated particles and titanium dioxide particles) in the particle slurry is preferably 5% by mass or more and 40% by mass or less, more preferably 10% by mass or more and 35% by mass or less, and more preferably 15% by mass or more. 25 mass% or less is especially preferable. By making the concentration of the particle slurry in the above range, the efficiency of particle aggregation can be improved.
粒子スラリーの濃度が上記下限未満の場合は、凝集剤の添加によっても、粒子が好適な粒径にまで凝集しないおそれがある。一方、粒子スラリーの濃度が上記上限を超える場合は、粘度が高すぎて作業性が低下したり、また、複合粒子の粒度分布が広がり、歩留まりが低下するおそれがある。 When the concentration of the particle slurry is less than the lower limit, the particles may not aggregate to a suitable particle size even by the addition of a flocculant. On the other hand, when the concentration of the particle slurry exceeds the above upper limit, the viscosity is too high and workability may be deteriorated, or the particle size distribution of the composite particles may be widened to reduce the yield.
また、凝集剤の添加量としては、再生粒子及び二酸化チタン粒子の合計固形分に対して、固形分換算で２００ｐｐｍ以上３，０００ｐｐｍ以下が好ましく、１，０００ｐｐｍ以上２，５００ｐｐｍ以下がさらに好ましく、１，５００ｐｐｍ以上２，０００ｐｐｍ以下が例えば再生粒子がもつブロードな粒度分布において、粒径の小さい粒子同士は凝集が進み、一方、粒径の元々大きい粒子は凝集が進行しにくい効果を効果的に発揮するため特に好ましい。 The addition amount of the flocculant is preferably 200 ppm or more and 3,000 ppm or less, more preferably 1,000 ppm or more and 2500 ppm or less in terms of solid content, based on the total solid content of the regenerated particles and titanium dioxide particles. In the broad particle size distribution of regenerated particles, for example, in the broad particle size distribution of 500 ppm to 2,000 ppm, agglomeration of particles having a small particle diameter progresses, whereas a particle having an originally large particle diameter effectively exhibits the effect that aggregation does not easily proceed. Therefore, it is particularly preferable.
凝集剤の添加量が上記下限未満の場合は、十分な凝集を発揮させることができず、歩留まりの向上効果が発揮されない場合がある。逆に、凝集剤の添加量が上記上限を超えると、スラリーの増粘が顕著に生じたり、三次、四次凝集が生じ、得られる紙の紙力が低下する場合がある。 When the addition amount of the flocculant is less than the above lower limit, sufficient aggregation cannot be exhibited, and the yield improvement effect may not be exhibited. On the contrary, if the addition amount of the flocculant exceeds the above upper limit, the viscosity of the slurry may be significantly increased, or tertiary and quaternary aggregation may occur, and the paper strength of the obtained paper may be reduced.
＜（２）シリカ被覆工程＞
このシリカ被覆工程においては、上記工程で得られた凝集体の表面にシリカを被覆させる。このシリカの被覆方法としては、凝集体スラリーに珪酸アルカリ水溶液と鉱酸とをこの順に添加し、凝集体表面にシリカを被覆させる方法や、ケイ酸アルカリ水溶液に凝集体スラリーを加えて混合し、その後鉱酸を添加してシリカを被覆させる方法などを挙げることができる。
<(2) Silica coating step>
In this silica coating step, silica is coated on the surface of the aggregate obtained in the above step. As a method for coating this silica, an alkali silicate aqueous solution and a mineral acid are added to the aggregate slurry in this order, and the surface of the aggregate is coated with silica, or the aggregate slurry is added to the alkali silicate aqueous solution and mixed. Then, a method of adding a mineral acid to coat silica can be exemplified.
上記珪酸アルカリ水溶液は特に限定されないが、珪酸ナトリウム溶液（３号水ガラス）が入手に容易である点で望ましい。珪酸アルカリ溶液の濃度は水溶液中の珪酸分（ＳｉＯ２換算）で３〜１０質量％が好適である。１０質量％を超えると形成される凝集体にシリカが被覆された複合粒子はシリカ被覆複合粒子ではなく、ホワイトカーボンで被覆されてしまい、芯部（凝集体）を形成する再生粒子及び二酸化チタンの光学的特性が全く発揮されなくなってしまうおそれがある。また、３質量％未満では得られる複合粒子中のシリカ成分が低下するおそれがある。 Although the said alkali silicate aqueous solution is not specifically limited, A sodium silicate solution (No. 3 water glass) is desirable at the point which is easy to acquire. The concentration of the alkali silicate solution is preferably 3 to 10% by mass in terms of the silicic acid content in the aqueous solution (in terms of SiO2). The composite particles in which the aggregate formed when the content exceeds 10% by mass is coated with silica are not silica-coated composite particles, but are coated with white carbon, and the regenerated particles that form the core (aggregate) and titanium dioxide There is a risk that the optical characteristics may not be exhibited at all. On the other hand, if it is less than 3% by mass, the silica component in the resulting composite particles may be lowered.
上記鉱酸としては希硫酸、希塩酸、希硝酸などの鉱酸の希釈液等が挙げられるが、価格や、ハンドリングの点、再生粒子中のカルシウム分の溶出防止や設備・装置の腐食対策と言った理由で希硫酸が最も好ましい。さらに、希硫酸を使用する場合の添加時の濃度は、０．２〜４．０モル濃度が好ましい。また、鉱酸添加量が多いほど短時間内にシリカが析出するので、それらの条件に合わせて添加速度を調整することが好ましい。なお、５分以内の添加は、均一な反応系の構成が不十分になるおそれがある。 Examples of the mineral acid include dilute sulfuric acid, dilute hydrochloric acid, dilute nitric acid and other mineral acid dilutions, but they are price, handling, calcium elution prevention from regenerated particles, and corrosion prevention of equipment / equipment. For this reason, dilute sulfuric acid is most preferable. Further, the concentration when adding dilute sulfuric acid is preferably 0.2 to 4.0 molar. Moreover, since silica precipitates in a short time, so that there is much mineral acid addition amount, it is preferable to adjust an addition rate according to those conditions. In addition, there is a possibility that the addition within 5 minutes may result in an insufficient uniform reaction system configuration.
本工程における反応温度に関しては、６０〜１００℃の範囲が好ましい。本発明者らの鋭意検討の結果から、本発明に使用する再生粒子及び二酸化チタン粒子の凝集体とシリカとの反応温度はシリカの生成、結晶成長速度及び形成されたシリカ被覆複合粒子の力学的強度に影響を及ぼす。反応温度が６０℃未満ではシリカの生成・成長速度が遅く、形成されたシリカ被覆複合粒子の被覆性に劣り、被覆の剥落が生じやすく、填料内添紙の抄造時にかかる剪断力で被覆が壊れやすい。また、１００℃を超えると、水系反応であるためオートクレーブを使用しなければならないため反応工程が複雑になってしまう。 The reaction temperature in this step is preferably in the range of 60 to 100 ° C. As a result of the present inventors' extensive studies, the reaction temperature between the regenerated particles and the aggregates of titanium dioxide particles used in the present invention and the silica is determined by the formation of silica, the crystal growth rate, and the dynamics of the formed silica-coated composite particles. Affects strength. If the reaction temperature is less than 60 ° C, the silica formation / growth rate is slow, the coverage of the formed silica-coated composite particles is inferior, the coating is easily peeled off, and the coating breaks due to the shearing force applied when making the filler-added paper. Cheap. Moreover, when it exceeds 100 degreeC, since it is a water-system reaction, since an autoclave must be used, a reaction process will become complicated.
また、本工程における反応保持時間（鉱酸の添加時間）としては、２０分以上３時間以下が好ましく、３０分以上２時間以下がさらに好ましい。反応保持時間が上記下限未満の場合は、十分なシリカ被覆が行われないおそれがある。逆に、反応保持時間が上記上限を超えると、シリカ被覆量が多すぎて、複合粒子の粒径が大きくなりすぎ、この結果、紙力や不透明度の低下などが生じるおそれがある。 In addition, the reaction holding time (mineral acid addition time) in this step is preferably 20 minutes or longer and 3 hours or shorter, and more preferably 30 minutes or longer and 2 hours or shorter. When the reaction holding time is less than the above lower limit, sufficient silica coating may not be performed. On the other hand, when the reaction holding time exceeds the above upper limit, the silica coating amount is too large, and the particle size of the composite particles becomes too large. As a result, the paper strength and opacity may be lowered.
また、再生粒子と二酸化チタン粒子との凝集体のシリカ被覆を行う場合、例えば凝集体を珪酸アルカリ水溶液に添加、分散しスラリーを調製するが、このスラリー濃度は、３〜３５質量％が好ましい。スラリー濃度を調整することにより、形成されるシリカ被覆複合粒子の粒径がコントロールされると同時に凝集体とシリカの組成比率を決めることができる。 Moreover, when performing silica coating of the aggregate of regenerated particles and titanium dioxide particles, for example, the aggregate is added to and dispersed in an alkali silicate aqueous solution to prepare a slurry. The slurry concentration is preferably 3 to 35% by mass. By adjusting the slurry concentration, the particle size of the silica-coated composite particles to be formed can be controlled, and at the same time, the composition ratio of the aggregate and silica can be determined.
好ましいシリカ被覆工程としては、両粒子の凝集体を珪酸アルカリ水溶液に添加・分散し凝集体スラリーとして調製する。その後、このスラリーを攪拌しながら、液温を６０〜１００℃の範囲に保持して鉱酸を添加し、シリカゾルを生成させる。この混合液（凝集体、ケイ酸アルカリ及び鉱酸の混合液）のｐＨを中性〜弱アルカリ性、好ましくは混合液をｐＨ８〜１１の範囲に調整することによりシリカ被覆複合粒子を得ることができる。 As a preferable silica coating step, an aggregate of both particles is added and dispersed in an aqueous alkali silicate solution to prepare an aggregate slurry. Thereafter, while stirring the slurry, the liquid temperature is maintained in the range of 60 to 100 ° C., and a mineral acid is added to form a silica sol. Silica-coated composite particles can be obtained by adjusting the pH of the mixed solution (mixed solution of agglomerates, alkali silicate and mineral acid) to neutral to weakly alkaline, and preferably the mixed solution to a pH of 8 to 11. .
＜複合粒子内添紙＞
本発明の複合粒子内添紙は、上記複合粒子が内添されたものである。当該複合粒子内添紙によれば、上記複合粒子が内添されているため、この填料としての複合粒子の歩留りが高く、白紙不透明度や印刷不透明度を高めることができる。
<Composite particle paper>
The composite particle internal paper of the present invention is one in which the composite particles are internally added. According to the composite particle internal paper, since the composite particles are internally added, the yield of the composite particles as the filler is high, and the white paper opacity and the printing opacity can be increased.
本発明の複合粒子を内添填料として用いて複合粒子内添紙を製造する方法は、通常の填料内添紙の製造方法と同様であり、例えば当該複合粒子と必要に応じて他の填料とを混合したスラリーをパルプ原料スラリーに添加し、さらに必要に応じて紙力増強剤、サイズ剤、歩留向上剤等の添加剤を加えた紙料スラリーとし、これを抄紙することにより得られる。パルプ原料（固形分）に対する填料添加率は、１〜５０質量％、好適には３〜３０質量％である。 The method for producing a composite particle-added paper using the composite particles of the present invention as an internal filler is the same as the method for producing an ordinary filler-added paper. For example, the composite particles and, if necessary, other fillers and It is obtained by adding a slurry mixed with a pulp raw material slurry and making a paper slurry containing additives such as a paper strength enhancer, a sizing agent, and a yield improver, if necessary, and papermaking. The filler addition rate with respect to the pulp raw material (solid content) is 1 to 50% by mass, preferably 3 to 30% by mass.
パルプ原料スラリーに添加する添加剤としては公知のものを用いることができ、例えば紙力増強剤としては澱粉類、植物性ガム、水性セルロース誘導体、ポリアクリルアミド等を、サイズ剤としてはロジン、澱粉、ＣＭＣ（カルボキシルメチルセルロース）、ポリビニルアルコール、アルキルケテンダイマー、ＡＳＡ（アルケニル無水コハク酸）、中性ロジン等を、また歩留向上剤としてはポリアクリルアミド及びその共重合体、第４級アンモニウム塩等を挙げることができる。資料スラリーには、さらに必要に応じて染料、顔料等の色料を添加してもよい。 As additives to be added to the pulp raw material slurry, known ones can be used. For example, starch, vegetable gum, aqueous cellulose derivative, polyacrylamide and the like are used as a paper strength enhancer, and rosin, starch, CMC (carboxyl methyl cellulose), polyvinyl alcohol, alkyl ketene dimer, ASA (alkenyl succinic anhydride), neutral rosin, etc., and yield improvers include polyacrylamide and copolymers thereof, quaternary ammonium salts, etc. be able to. You may add coloring materials, such as dye and a pigment, to a data slurry further as needed.
上記紙料スラリーを公知の抄紙機で抄造することにより複合粒子内添紙を製造することができる。当該複合紙料内添紙の坪量は特に限定されないが、通常１０〜３００ｇ／ｍ２程度である。 By making the paper stock slurry with a known paper machine, composite particle-containing paper can be produced. The basis weight of the composite paper-added paper is not particularly limited, but is usually about 10 to 300 g / m 2 .
＜塗工紙＞
本発明の塗工紙は、基紙と、この基紙の少なくとも一方の面に形成される１層又は複数層の塗工層とを有する塗工紙であって、上記塗工層が上記複合粒子を含有することを特徴とする。当該塗工紙によれば、上記複合粒子を顔料として塗工層に用いているため、白紙不透明度及び印刷後不透明度に優れる。
<Coated paper>
The coated paper of the present invention is a coated paper having a base paper and one or more coating layers formed on at least one surface of the base paper, wherein the coating layer is the composite It is characterized by containing particles. According to the coated paper, since the composite particles are used as a pigment in the coating layer, the white paper opacity and the opacity after printing are excellent.
本発明の複合粒子を用いて塗工紙を製造する方法は、通常の塗工紙の製造方法と同様であり、例えば本発明の複合粒子を必要に応じて他の顔料と混合し、分散剤を添加して得たスラリーを接着剤や他の添加剤を混合して塗料を調整し、これを中質紙、上質紙等の紙材上に塗工することにより得られる。 The method for producing coated paper using the composite particles of the present invention is the same as the method for producing ordinary coated paper. For example, the composite particles of the present invention are mixed with other pigments as necessary, and a dispersing agent is used. It is obtained by mixing the slurry obtained by adding an adhesive and other additives to prepare a coating material, and coating the slurry on a paper material such as medium-quality paper or high-quality paper.
当該複合粒子を用いて塗工紙を製造する場合においても、当該複合粒子の吸油度は、３０〜１５０ｍＬ／１００ｇの範囲が好ましい。これは、接着剤と混合して使用する場合、その塗工液中において複合粒子が接着剤を吸収し、その真密度が低下するため沈降が抑制され、さらに複合粒子が塗工層中で偏った沈降を呈さなくなり、塗工層中で均一に分散される効果が顕著に現れるためである。この吸油度が３０ｍＬ／１００ｇ以下の場合には上記の効果が不十分であり、複合粒子の真比重と塗工液の比重との差により複合粒子が沈降して塗工層中に不均一な分散状態になるので好ましくない。逆に、吸油度が１５０ｍＬ／１００ｇを越える場合では、塗工層に塗工顔料として配合した場合には、ラテックス、澱粉等のバインダーを吸収し、塗工層強度が低下する不都合が生じる。 Also when manufacturing coated paper using the said composite particle, the oil absorption degree of the said composite particle has the preferable range of 30-150 mL / 100g. This is because when mixed with an adhesive, the composite particles absorb the adhesive in the coating solution, and the true density is reduced, so that sedimentation is suppressed, and the composite particles are biased in the coating layer. This is because the effect of being uniformly dispersed in the coating layer appears remarkably. When the oil absorption is 30 mL / 100 g or less, the above effect is insufficient, and the composite particles settle out due to the difference between the true specific gravity of the composite particles and the specific gravity of the coating liquid, and are not uniform in the coating layer. Since it will be in a dispersed state, it is not preferable. On the contrary, when the oil absorption exceeds 150 mL / 100 g, when blended as a coating pigment in the coating layer, a binder such as latex or starch is absorbed, resulting in a disadvantage that the coating layer strength is lowered.
塗工液に含有される接着剤としては、公知のものを用いることができ、例えばスチレン−ブタジエン共重合体、メチルメタクリレート−ブタジエン共重合体等の共役ジエン系共重合体ラテックス、アクリル酸エステル及び／又はメタクリル酸エステルの重合体又は共重合体等のアクリル系重合体ラテックス、エチレン−酢酸ビニル共重合体等のビニル系重合体ラテックス、若しくはこれらの各種重合体ラテックスをカルボキシル基等の官能基含有単量体で変性したアルカリ部分溶解性又はアルカリ非溶解性の重合体ラテックス等が使用される。 As the adhesive contained in the coating liquid, known ones can be used, for example, conjugated diene copolymer latex such as styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer, acrylic acid ester, and the like. // Acrylic polymer latex such as a polymer or copolymer of methacrylic acid ester, vinyl polymer latex such as ethylene-vinyl acetate copolymer, or a functional group such as a carboxyl group containing these various polymer latexes An alkali partially soluble or alkali insoluble polymer latex modified with a monomer is used.
さらに上記のような合成接着剤のほかに、例えばカチオン化澱粉、酸化澱粉、酸素変性澱粉、熱化学変性澱粉、エーテル化澱粉、エステル化澱粉、冷水可溶澱粉等の澱粉類、カルボキシメチルセルロース、ヒドロキシメチルセルロース等のセルロース類、ポリビニルアルコール、オレフィン−無水マレイン酸樹脂等の水溶性合成接着剤等を適宜選択して併用できる。また、必要に応じて、顔料スラリーや塗料中には消泡剤、耐水化剤、流動性変性剤、着色剤、蛍光増白剤等の各種添加剤が添加される。また、分散剤としてはヘキサメタリン酸ソーダ、ポリアクリル酸ソーダ等が挙げられる。 In addition to the above synthetic adhesives, for example, cationized starch, oxidized starch, oxygen-modified starch, thermochemically modified starch, etherified starch, esterified starch, starch such as cold water soluble starch, carboxymethylcellulose, hydroxy Celluloses such as methylcellulose, water-soluble synthetic adhesives such as polyvinyl alcohol and olefin-maleic anhydride resin can be appropriately selected and used in combination. Moreover, various additives, such as an antifoamer, a water resistance agent, a fluidity modifier, a coloring agent, and a fluorescent brightening agent, are added to the pigment slurry and paint as necessary. Examples of the dispersant include sodium hexametaphosphate and sodium polyacrylate.
塗工液の塗工方法としては、塗工量に応じて、エアーナイフ、ブレード、ゲートロール、ロッド、バー、キャスト、グラビア、カーテン等の公知の塗工機（コーター）で行うことができる。塗工量は片面当たり乾燥質量で通常数〜数１０ｇ／ｍ２程度である。 As a coating method of the coating liquid, it can be performed by a known coating machine (coater) such as an air knife, a blade, a gate roll, a rod, a bar, a cast, a gravure, or a curtain depending on the coating amount. The coating amount is usually about several to several tens g / m 2 in terms of dry mass per side.
このようにして得られた乾燥後の塗工紙は、一般に印刷適性（例えば、高平滑や高光沢）を付与する目的で、カレンダに通紙して加圧仕上げが施される。この場合のカレンダ装置としては、例えばスーパーカレンダ、グロスカレンダ、ソフトコンパクトカレンダなどの金属またはドラムと弾性ロールの組み合わせになる各種カレンダが、オンマシン又はオフマシン仕様で適宜使用できる。 The coated paper obtained after drying is generally subjected to pressure finishing by passing it through a calendar for the purpose of imparting printability (for example, high smoothness and high gloss). As the calendar device in this case, for example, various calenders such as a super calender, a gloss calender, a soft compact calender, or a combination of a drum and an elastic roll can be used as appropriate in an on-machine or off-machine specification.
＜再生粒子の製造方法＞
ここで、本発明の複合粒子に好適な再生粒子の製造方法について、原料並びに脱水、熱処理及び粉砕の各工程の順に詳説する。なお、熱処理工程と粉砕工程との間に、配合・スラリー化工程を有することが好ましく、さらに必要に応じてその他の工程を設けることができる。
<Method for producing regenerated particles>
Here, the method for producing regenerated particles suitable for the composite particles of the present invention will be described in detail in the order of raw materials and steps of dehydration, heat treatment and pulverization. In addition, it is preferable to have a mixing | blending / slurry process between a heat treatment process and a grinding | pulverization process, and also other processes can be provided as needed.
（原料）
再生粒子の原料としては、主原料として製紙スラッジが用いられ、製紙スラッジの中でも、脱墨フロスが好適に用いられる。脱墨フロスとは、古紙パルプを製造する古紙処理工程において、主に、古紙に付着したインクを取り除く脱墨工程でパルプ繊維から分離されるものをいう。製紙における古紙パルプ製造工程では、安定した品質の古紙パルプを連続的に生産する目的から、使用する古紙の選定、選別を行い、一定品質の古紙を使用する。そのため古紙パルプ製造工程に持ち込まれる無機物の種類やその比率、量が基本的に一定になる。しかも古紙中に未燃物の変動要因となるビニールやフィルムなどのプラスチック類が含まれていた場合も、これらの異物は脱墨フロスを得る脱墨工程に至る前段階で除去される。したがって、脱墨フロスは、工場排水工程や製紙原料調成工程等の、他の工程で発生する製紙スラッジと比べて、極めて安定した品質の再生粒子を製造するための原料となる。
(material)
As the raw material for the regenerated particles, papermaking sludge is used as the main raw material, and among the papermaking sludge, deinking floss is preferably used. The deinking floss refers to what is separated from the pulp fiber in the deinking process for removing ink adhering to the used paper in the used paper processing process for producing the used paper pulp. In the used paper pulp manufacturing process in papermaking, for the purpose of continuously producing used paper pulp of stable quality, the used paper is selected and selected, and used paper of a certain quality is used. For this reason, the types, ratios, and amounts of inorganic substances brought into the used paper pulp manufacturing process are basically constant. Moreover, even if the waste paper contains plastics such as vinyl and film that cause fluctuations in unburned materials, these foreign matters are removed at the stage before the deinking process for obtaining the deinking floss. Accordingly, the deinking floss is a raw material for producing regenerated particles having extremely stable quality as compared with papermaking sludge generated in other processes such as a factory drainage process and a papermaking raw material preparation process.
（脱水工程）
脱水工程は、脱墨フロス等の原料の水分を所定割合まで除去する工程である。例えば、古紙パルプを製造する脱墨工程においてパルプ繊維から分離された脱墨フロスは、種々の操作を経て、公知の脱水設備により脱水される。
(Dehydration process)
The dehydration step is a step of removing moisture of a raw material such as deinking floss up to a predetermined ratio. For example, deinking floss separated from pulp fibers in a deinking process for producing waste paper pulp is subjected to various operations and dehydrated by a known dewatering facility.
脱水工程の一例としては、以下の工程が挙げられる。まず一の脱水手段であるスクリーンによって、脱墨フロスから水を分離して脱水する。このスクリーンにおいて水分率を７０％〜９０％に脱水した脱墨フロスは、別の脱水手段である例えばスクリュープレスに送り、更に所定の水分率まで脱水する。 Examples of the dehydration step include the following steps. First, water is separated from the deinking floss by a screen as one dehydrating means and dehydrated. The deinking floss dehydrated to 70% to 90% in this screen is sent to another dehydrating means such as a screw press, and further dehydrated to a predetermined moisture content.
脱水後の原料（脱墨フロス）は、６０％以下、好ましくは３０％以上５０％未満、より好ましくは３０％以上４５％以下、特に好ましくは３０％超４０％以下の含水状態とするとよい。 The raw material after dehydration (deinking floss) is 60% or less, preferably 30% or more and less than 50%, more preferably 30% or more and 45% or less, and particularly preferably more than 30% and 40% or less.
脱水後の原料の水分率が６０％を超えると、熱処理工程における処理温度の低下を招き、加熱のためのエネルギーロスが多大になるとともに、原料の燃焼ムラが生じやすくなり均一な燃焼を進め難くなる。また、排出される排ガス中の水分が多くなり、ダイオキシン対策における再燃焼処理効率の低下と、排ガス処理設備の負荷が大きくなる不都合を有する。他方、脱水後の原料の水分率が３０％未満と低いと、脱水処理エネルギーの削減に反する。 When the moisture content of the raw material after dehydration exceeds 60%, the processing temperature in the heat treatment process is lowered, energy loss for heating increases, and uneven combustion of the raw material is likely to occur, making it difficult to promote uniform combustion. Become. Further, the exhaust gas discharged has a large amount of moisture, which has the disadvantage that the efficiency of the recombustion treatment in the dioxin countermeasures is reduced and the load of the exhaust gas treatment equipment is increased. On the other hand, if the moisture content of the raw material after dehydration is as low as less than 30%, it is contrary to the reduction of dehydration energy.
上述のように、原料（脱墨フロス）の脱水を多段工程で行い急激な脱水を避けると、無機物の流出が抑制でき脱墨フロスのフロックが硬くなりすぎるおそれがない。脱水処理においては、脱墨フロスを凝集させる凝集剤等の脱水効率を向上させる助剤を添加しても良いが、凝集剤には、鉄分を含まないものを使用することが好ましい。鉄分が含有されると、鉄分の酸化により再生粒子の白色度が低下するおそれがある。 As described above, if the raw material (deinking floss) is dehydrated in a multi-stage process and abrupt dehydration is avoided, the outflow of inorganic substances can be suppressed and the deinking floss flocs do not become too hard. In the dehydration treatment, an auxiliary agent for improving the dehydration efficiency such as an aggregating agent for aggregating the deinking floss may be added, but it is preferable to use an aggregating agent that does not contain iron. When iron is contained, the whiteness of the regenerated particles may be reduced due to oxidation of iron.
脱水工程のための設備は、再生粒子の他の工程の設備に隣接することが生産効率の面で好ましいが、予め古紙パルプ製造工程に隣接して設備を設け、脱水を行った物を搬送することも可能であり、トラックやベルトコンベア等の搬送手段によって定量供給機まで搬送し、この定量供給機から熱処理工程に供給することもできる。 It is preferable in terms of production efficiency that the equipment for the dehydration process is adjacent to the equipment of other processes of the regenerated particles, but the equipment is provided in advance adjacent to the waste paper pulp manufacturing process to transport the dehydrated material. It is also possible to transport to a metering feeder by a transport means such as a truck or a belt conveyor, and to supply the heat treatment process from this metering feeder.
脱水後の原料は、熱処理工程に供給する前に、粉砕機（又は解砕機）等により、平均粒子径４０ｍｍ以下、好ましくは平均粒子径３ｍｍ〜３０ｍｍ、より好ましくは平均粒子径５ｍｍ〜２０ｍｍに粒子径を揃えると好適であり、また、粒子径５０ｍｍ以下の割合が７０質量％以上となるように粒子径を揃えると好適である。平均粒子径が３ｍｍ未満では過燃焼になりやすい。逆に、平均粒子径が４０ｍｍを超えると原料芯部まで均一に燃焼を図るのが困難になる。 The raw material after dehydration is a particle having an average particle diameter of 40 mm or less, preferably an average particle diameter of 3 mm to 30 mm, more preferably an average particle diameter of 5 mm to 20 mm by a pulverizer (or pulverizer) before being supplied to the heat treatment step. It is preferable to arrange the diameters, and it is preferable to arrange the particle diameters so that the ratio of the particle diameters of 50 mm or less is 70% by mass or more. If the average particle size is less than 3 mm, overcombustion tends to occur. Conversely, when the average particle diameter exceeds 40 mm, it becomes difficult to uniformly burn the raw material core.
上記脱水工程における平均粒子径及び粒子径の割合は、攪拌式の分散機で充分分散させた試料溶液を用いて測定した値である。なお、後述する各熱処理工程における粒子径は、ＪＩＳ−Ｚ８８０１−２：２０００に基づき、金属製の板ふるいにて測定した値である。 The average particle diameter and the ratio of the particle diameter in the dehydration step are values measured using a sample solution sufficiently dispersed by a stirring type disperser. In addition, the particle diameter in each heat processing process mentioned later is the value measured with the metal plate sieve based on JIS-Z8801-2: 2000.
（熱処理工程）
熱処理工程は、脱水された原料の更なる水分除去のための乾燥と、比較的低温の第１の燃焼とを一連で行う第１熱処理工程、及び第１熱処理工程で得られた熱処理物を再度、第１熱処理工程より高温で熱処理（燃焼）する第２熱処理工程を含む。このように順に温度を上げていく２段階の熱処理工程を経ることで、原料の過燃焼を抑え、得られる再生粒子をスラリー化した際の増粘を抑制することができる。また、熱処理温度としては、比較的低温で行うことで、同様に原料の過燃焼を抑え、得られる再生粒子をスラリー化した際の増粘を抑制することができる。熱処理温度の上限としては、具体的には７８０℃が好ましく、７５０℃がさらに好ましい。
(Heat treatment process)
The heat treatment step includes a first heat treatment step in which drying for further moisture removal of the dehydrated raw material and a first combustion at a relatively low temperature are performed in series, and the heat treatment product obtained in the first heat treatment step is again used. And a second heat treatment step for heat treatment (combustion) at a higher temperature than the first heat treatment step. By passing through the two-stage heat treatment step in which the temperature is raised in this way, over-combustion of the raw material can be suppressed, and thickening when the obtained regenerated particles are slurried can be suppressed. In addition, by performing the heat treatment at a relatively low temperature, it is possible to similarly suppress over-combustion of the raw material and suppress thickening when the obtained regenerated particles are slurried. Specifically, the upper limit of the heat treatment temperature is preferably 780 ° C, more preferably 750 ° C.
（第１熱処理工程）
脱水工程を経た原料は、第１熱処理工程として、例えば本体が横置きで中心軸周りに回転する内熱キルン炉を用いて、熱処理される。
(First heat treatment step)
The raw material that has undergone the dehydration step is heat-treated as a first heat treatment step using, for example, an internal heat kiln furnace in which the main body is placed horizontally and rotates around the central axis.
この内熱キルン炉においては、熱風発生炉にて生成された熱風が、排出口側から原料の流れと向流するように送り込まれる。この内熱キルン炉の一方側には排ガスチャンバーが、他方側には排出チャンバーが設けられている。排出チャンバーを貫通して熱風が内熱キルン炉の他方側から吹き込まれ、上記一方側から装入され、内熱キルン炉の回転に伴って上記他方側へ順次移送される原料の乾燥及び燃焼を行うようになっている。 In this internal heat kiln furnace, hot air generated in the hot air generation furnace is sent from the outlet side so as to counter-flow with the raw material flow. An exhaust gas chamber is provided on one side of the internal heat kiln furnace, and an exhaust chamber is provided on the other side. Hot air is blown from the other side of the internal heat kiln furnace through the discharge chamber, and is charged from the other side to dry and burn the raw material sequentially transferred to the other side as the internal heat kiln furnace rotates. To do.
このように第１熱処理工程においては、原料を、本体が横置きで中心軸周りに回転する内熱キルン炉によって乾燥・燃焼することにより、供給口から排出口に至るまで、緩やかに乾燥と有機分の燃焼とを行うことができ、熱処理物の微粉化が抑制され、凝集体形成、硬い・柔らかい等さまざまな性質を有する原料の燃焼度合いの制御と、粒揃えとを、安定的に行うことができる。なお、乾燥を別工程に分割し、例えば吹上げ式の乾燥機によって乾燥させることもできる。 In this way, in the first heat treatment step, the raw material is dried and burned gently from the supply port to the discharge port by drying and burning in the internal heat kiln furnace in which the main body is placed horizontally and rotates around the central axis. Can control the degree of combustion of raw materials with various properties such as agglomeration, hard and soft, and stable grain alignment. Can do. In addition, drying can be divided into separate steps and dried by, for example, a blow-up type dryer.
第１熱処理工程における熱処理温度（例えば、内熱キルン炉の出口温度（熱風温度））は、３００℃以上６００℃未満、好ましくは４００℃以上５５０℃未満、より好ましくは４００℃以上５００℃以下が好適である。第１熱処理工程においては、容易に燃焼可能な有機物を緩やかに燃焼させ、燃焼し難い残カーボンの生成を抑える目的から、上記範囲の温度で熱処理するのが好ましい。過度に温度が低いと、有機物の燃焼が不十分であり、他方、過度に温度が高いと過燃焼が生じ、炭酸カルシウムの分解によって酸化カルシウムが生成し易くなる。また、温度が６００℃以上の場合は、硬い・柔らかい等さまざまな性質を有する脱水物の粒揃えが進行するよりも早くに乾燥・燃焼が局部的に進むため、粒子表面と粒子内部との未燃率の差を少なくし、均一にするのが困難になる。 The heat treatment temperature in the first heat treatment step (for example, the outlet temperature (hot air temperature) of the internal heat kiln furnace) is 300 ° C. or higher and lower than 600 ° C., preferably 400 ° C. or higher and lower than 550 ° C., more preferably 400 ° C. or higher and 500 ° C. or lower. Is preferred. In the first heat treatment step, it is preferable to heat-treat at a temperature in the above range for the purpose of slowly burning the combustible organic matter and suppressing the formation of residual carbon that is difficult to burn. When the temperature is excessively low, the organic matter is not sufficiently combusted. On the other hand, when the temperature is excessively high, overcombustion occurs, and calcium oxide is easily generated by decomposition of calcium carbonate. In addition, when the temperature is 600 ° C. or higher, drying / combustion proceeds locally faster than the alignment of dehydrated materials having various properties such as hard and soft, so that the particle surface and the interior of the particle are not. It becomes difficult to reduce the difference in the flammability and make it uniform.
第１熱処理工程は、原料に含有される燃焼容易な有機物を緩慢に燃焼させ、残カーボンの生成を抑制するため、上記条件下で、３０分〜９０分の滞留（熱処理）時間で熱処理させるのが好ましい。熱処理時間が３０分未満では、十分な燃焼が行われず残カーボンの割合が多くなる。他方、熱処理時間が９０分を超えると、脱水物の過燃焼による炭酸カルシウムの熱分解が生じ、また、得られる再生粒子が極めて硬くなる。有機物の燃焼及び生産効率の面では、４０分〜８０分の滞留時間で熱処理させるのが好ましい。恒常的な品質を確保するためには、５０分〜７０分の滞留時間で熱処理燃焼させるのが好ましい。 In the first heat treatment step, an easily combusted organic substance contained in the raw material is slowly burned, and in order to suppress the formation of residual carbon, the heat treatment is performed for 30 minutes to 90 minutes in the residence (heat treatment) time under the above conditions. Is preferred. If the heat treatment time is less than 30 minutes, sufficient combustion is not performed and the ratio of remaining carbon increases. On the other hand, when the heat treatment time exceeds 90 minutes, thermal decomposition of calcium carbonate occurs due to excessive combustion of the dehydrated product, and the obtained regenerated particles become extremely hard. In terms of organic combustion and production efficiency, heat treatment is preferably performed with a residence time of 40 minutes to 80 minutes. In order to ensure constant quality, it is preferable to perform heat treatment combustion with a residence time of 50 minutes to 70 minutes.
（第２熱処理工程）
第１熱処理工程を経た原料は、第２熱処理工程として、例えば本体が横置きで中心軸周りに回転する外熱ジャケットを有する外熱キルン炉を用いて、熱処理される。このように、第１及び第２熱処理工程を経ることで、原料中の有機分が燃焼除去され、無機物が熱処理物として排出されることができる。
(Second heat treatment step)
The raw material which passed through the 1st heat treatment process is heat-processed using the external heat kiln furnace which has the external heat jacket which a main body turns sideways and rotates around a central axis as a 2nd heat treatment process. In this way, through the first and second heat treatment steps, the organic component in the raw material is burned and removed, and the inorganic substance can be discharged as a heat treatment product.
第２熱処理工程においては、第１熱処理工程で燃焼しきれなかった残留有機物、例えば残カーボンを燃焼させるため、第１熱処理工程において供給される原料の粒子径よりも小さい粒子径に調整された熱処理物を用いることが好ましい。第１熱処理工程後の熱処理物の粒揃えは、平均粒子径１０ｍｍ以下となるように調整するのが好ましく、平均粒子径１〜８ｍｍとなるように調整するのがより好ましく、平均粒子径１〜５ｍｍとなるように調整するのが特に好ましい。第２熱処理工程における外熱キルン炉入口での平均粒子径が１ｍｍ未満では過燃焼の危惧があり、平均粒子径１０ｍｍ超では、残カーボンの燃焼が困難であり、芯部まで燃焼が進まず得られる再生粒子の白色度が低下するおそれがある。 In the second heat treatment step, in order to burn the residual organic matter that could not be burned in the first heat treatment step, for example, residual carbon, the heat treatment adjusted to a particle size smaller than the particle size of the raw material supplied in the first heat treatment step. It is preferable to use a product. The grain alignment of the heat-treated product after the first heat treatment step is preferably adjusted so as to be an average particle diameter of 10 mm or less, more preferably adjusted so as to be an average particle diameter of 1 to 8 mm, and an average particle diameter of 1 to It is particularly preferable to adjust to 5 mm. If the average particle diameter at the inlet of the external heat kiln in the second heat treatment step is less than 1 mm, there is a risk of overcombustion. If the average particle diameter exceeds 10 mm, the remaining carbon is difficult to burn, and combustion may not proceed to the core. There is a possibility that the whiteness of the regenerated particles may decrease.
外熱キルン炉の外熱源としては、外熱キルン炉内の温度制御が容易で、かつ長手方向の温度制御が容易な電気加熱方式の熱源が好適であり、したがって、電気ヒーターによる外熱キルン炉が好ましい。外熱源に電気を使用することにより、炉内の温度を細かく、かつ均一にコントロールすることができ、凝集体の形成、硬い・柔らかい等のさまざまな性質を有する熱処理物の燃焼度合いの制御と、粒揃えとを、安定的に行うことができる。また、電気炉は、電気ヒーターを炉の流れ方向に複数設けることで、任意に温度勾配を設けることが可能であると共に、熱処理物の温度を一定時間、一定温度に保持することができ、第１熱処理工程を経た熱処理物中の残留有機分、特に残カーボンを第２熱処理工程で炭酸カルシウムの分解を来たすことなく限りなくゼロに近づけることができ、例えば重質炭酸カルシウムと比べて低いワイヤー摩耗度で、高白色度の再生粒子を得ることができる。 As the external heat source of the external heat kiln furnace, an electric heating type heat source that is easy to control the temperature in the external heat kiln furnace and easy to control the longitudinal temperature is suitable. Is preferred. By using electricity as an external heat source, the temperature in the furnace can be finely and uniformly controlled, and the degree of combustion of the heat-treated product having various properties such as formation of aggregates, hard and soft, Grain alignment can be performed stably. In addition, by providing a plurality of electric heaters in the flow direction of the furnace, the electric furnace can arbitrarily provide a temperature gradient, and the temperature of the heat-treated product can be maintained at a constant temperature for a certain period of time. Residual organic content in the heat-treated product after one heat treatment step, especially residual carbon, can be brought to zero as much as possible without causing decomposition of calcium carbonate in the second heat treatment step, for example, low wire wear compared to heavy calcium carbonate And high whiteness regenerated particles can be obtained.
第２熱処理工程における熱処理温度は、好ましくは５５０℃〜７８０℃、より好ましくは６００℃〜７５０℃である。第２熱処理工程では、先に述べたように、第１熱処理工程で燃焼しきれなかった残留有機物、特に残カーボンを燃焼させる必要があるため、第１熱処理工程よりも高温で熱処理するのが好ましく、熱処理温度が５５０℃未満では、十分に残留有機物の燃焼を図ることができないおそれがあり、熱処理温度が７８０℃を超えると、熱処理物中の炭酸カルシウムの脱炭酸が進行し、粒子が硬くなるおそれがある。 The heat treatment temperature in the second heat treatment step is preferably 550 ° C to 780 ° C, more preferably 600 ° C to 750 ° C. In the second heat treatment step, as described above, since it is necessary to burn the residual organic matter that has not been burned in the first heat treatment step, particularly the residual carbon, it is preferable to perform the heat treatment at a higher temperature than the first heat treatment step. If the heat treatment temperature is less than 550 ° C., there is a possibility that the residual organic matter cannot be burned sufficiently. If the heat treatment temperature exceeds 780 ° C., decarboxylation of calcium carbonate in the heat treatment proceeds and the particles become hard. There is a fear.
第２熱処理工程としての外熱キルン炉における滞留（熱処理）時間としては、好ましくは６０分以上、より好ましくは６０分〜２４０分、特に好ましくは９０分〜１５０分、最適には１２０分〜１５０分が、残カーボンを完全に燃焼させるに望ましい。特に残カーボンの燃焼は炭酸カルシウムの分解をできる限り生じさせない高温で、緩慢に燃焼させる必要があり、滞留時間が６０分未満では、残カーボンの燃焼には短時間で不十分であり、他方、滞留時間が２４０分を超えると、炭酸カルシウムが分解するおそれがある。また、熱処理物の安定生産を行うにおいては、滞留時間を６０分以上、過燃焼防止、生産性確保のためには、滞留時間を２４０分以下とするのが好適である。 The residence (heat treatment) time in the external heat kiln furnace as the second heat treatment step is preferably 60 minutes or more, more preferably 60 minutes to 240 minutes, particularly preferably 90 minutes to 150 minutes, and most preferably 120 minutes to 150 minutes. Minutes are desirable for complete combustion of the remaining carbon. In particular, the remaining carbon must be burnt slowly at a high temperature that does not cause the decomposition of calcium carbonate as much as possible. If the residence time is less than 60 minutes, the remaining carbon is burnt in a short time, If the residence time exceeds 240 minutes, the calcium carbonate may be decomposed. In addition, in the stable production of the heat-treated product, it is preferable that the residence time is 60 minutes or more, and in order to prevent overcombustion and secure productivity, the residence time is 240 minutes or less.
第２熱処理工程としての外熱キルン炉から排出される熱処理物の平均粒子径は、１０ｍｍ以下、好ましくは１ｍｍ〜８ｍｍ、より好ましくは１ｍｍ〜４ｍｍに調整すると好適である。この調整は、例えば、熱処理物を一定のクリアランスを持った回転する２本ロールの間を通過させること等により行うことができる。 The average particle diameter of the heat-treated product discharged from the external heat kiln furnace as the second heat treatment step is preferably adjusted to 10 mm or less, preferably 1 mm to 8 mm, more preferably 1 mm to 4 mm. This adjustment can be performed, for example, by passing the heat-treated product between two rotating rolls having a certain clearance.
第２熱処理工程を経た熱処理物は、好適には凝集体であり、例えば冷却機により冷却された後、振動篩機などの粒径選別機により選別され、燃焼品サイロに一時貯留される。この後、配合・スラリー化工程及び粉砕工程で目的の粒子径に調整された後、再生粒子として填料等の用途先に仕向けられる。 The heat-treated product that has undergone the second heat treatment step is preferably an agglomerate, for example, cooled by a cooler, sorted by a particle size sorter such as a vibration sieve, and temporarily stored in a combustion product silo. Then, after adjusting to the target particle diameter in the blending / slurry step and the pulverization step, the particles are used as reclaimed particles for application destinations such as fillers.
なお、以上では、脱墨フロスを原料として用いた場合を例示したが、脱墨フロスを主原料に、抄紙工程における製紙スラッジ等の他の製紙スラッジを適宜混入させたものを原料とすることなどもできる。 In addition, although the case where the deinking floss was used as a raw material was illustrated above, the deinking floss was used as a raw material, and the raw material was appropriately mixed with other papermaking sludge such as paper sludge in the papermaking process. You can also.
（配合・スラリー化工程）
配合・スラリー化工程は、上記第２熱処理工程から排出される熱処理物に酸及び／又は塩を配合し、その熱処理物を水中に懸濁させてスラリー化させる工程である。
(Formulation / slurry process)
The blending / slurrying step is a step of blending an acid and / or salt into the heat-treated product discharged from the second heat treatment step and suspending the heat-treated product in water to make a slurry.
この熱処理物は、後工程である粉砕工程において、効果的な粉砕を図るために、ミキサー等を使用して水中に懸濁させ、スラリーとした後に粉砕するのが好ましい。この際のスラリー濃度（スラリー全体に対する添加された熱処理物の質量比）の下限としては、１５％が好ましく、２０％がさらに好ましい。また、このスラリー化濃度の上限としては、５０％が好ましく、４０％がさらに好ましい。スラリー化濃度が上記下限未満であると最終的に得られた粒子を固形状とする際に、多大なエネルギーが生じるなど生産効率が低下する。逆に、スラリー化濃度が上記上限を超えると、のちの粉砕工程において効果的な粉砕が困難となる、また凝固、固化が生じやすくなるなどのおそれがある。 This heat-treated product is preferably pulverized after being suspended in water by using a mixer or the like in order to achieve effective pulverization in the subsequent pulverization step. In this case, the lower limit of the slurry concentration (mass ratio of the heat-treated product added to the whole slurry) is preferably 15%, and more preferably 20%. Further, the upper limit of the slurry concentration is preferably 50%, and more preferably 40%. When the slurry concentration is less than the above lower limit, when the finally obtained particles are made into a solid state, production efficiency decreases, for example, enormous energy is generated. On the other hand, if the slurry concentration exceeds the above upper limit, effective pulverization may be difficult in the subsequent pulverization step, and solidification and solidification may easily occur.
上記酸及び／又は塩は、カルシウムイオンの存在下でカルシウム塩を析出し得るものである。当該酸及び／又は塩によれば、過燃焼によって生じた酸化カルシウムやメタカオリンに起因しスラリー中に溶け出したカルシウムイオンと反応し、カルシウム塩を析出させることで、カルシウムイオンとスラリー中に共存する珪酸イオンやアルミン酸イオンとの反応を抑え、硬化物質の生成を抑制させることができる。この結果、この酸及び／又は塩を用いることで、スラリーの凝固、固化を抑えることができる。 The acid and / or salt can precipitate a calcium salt in the presence of calcium ions. According to the acid and / or salt, it reacts with calcium ions dissolved in the slurry due to calcium oxide and metakaolin generated by overcombustion, and precipitates calcium salt, so that it coexists in the slurry with calcium ions. The reaction with silicate ions and aluminate ions can be suppressed, and the generation of a cured substance can be suppressed. As a result, by using this acid and / or salt, solidification and solidification of the slurry can be suppressed.
（粉砕工程）
粉砕工程は、上記工程にて得られたスラリーを粉砕し、微粒子化することで再生粒子を得る工程である。この粉砕工程においては、公知の粉砕装置等を用いることができる。この粉砕工程を経て、スラリーを適宜必要な粒子径に微細粒化することで、得られる再生粒子を塗工用の顔料、内添用の填料として好適に使用することができる。
(Crushing process)
The pulverization step is a step in which regenerated particles are obtained by pulverizing the slurry obtained in the above-described step to obtain fine particles. In this pulverization step, a known pulverizer or the like can be used. Through this pulverization step, the resulting regenerated particles can be suitably used as a pigment for coating and a filler for internal addition by finely pulverizing the slurry to a necessary particle size.
（その他の工程）
再生粒子の製造方法においては、原料の凝集工程、造粒工程や、各工程間における分級工程、スラリーを炭酸化する炭酸化工程等を設けてもよい。
(Other processes)
In the method for producing regenerated particles, a raw material aggregation process, a granulation process, a classification process between the processes, a carbonation process for carbonizing the slurry, and the like may be provided.
（炭酸化工程）
得られた再生粒子のスラリーは、そのままではｐＨが１２以上とアルカリ性を呈し、例えば、塗工用顔料用途における塗工液調整工程で他の薬品と反応して品質低下をまねくおそれがある。従って、熱処理物又は再生粒子中の酸化カルシウムを炭酸カルシウムに戻してｐＨを低減させるために、第１熱処理燃焼工程や第２熱処理工程において排出された排ガス中の二酸化炭素を利用して、例えば７〜９にｐＨ調整すると好適である。
(Carbonation process)
The obtained slurry of regenerated particles is as alkaline as pH of 12 or more as it is, and may react with other chemicals in a coating liquid adjusting step in the application of coating pigments, for example, and may cause quality deterioration. Therefore, in order to return the calcium oxide in the heat-treated product or the regenerated particles to calcium carbonate and reduce the pH, the carbon dioxide in the exhaust gas discharged in the first heat treatment combustion step or the second heat treatment step is used, for example, 7 It is preferable to adjust the pH to ˜9.
なお、この炭酸化工程は、配合・スラリー化工程と粉砕工程との間、粉砕工程と同時、又は粉砕工程の後に行ってもよい。なお、この二酸化炭素の吹き込みは、他の酸及び／又は塩の配合に替えて、又は加えて、炭酸の配合として、配合・スラリー化工程とすることもできる。 The carbonation step may be performed between the blending / slurry step and the pulverization step, simultaneously with the pulverization step, or after the pulverization step. The carbon dioxide blowing may be a blending / slurrying step as a blending of carbonic acid instead of or in addition to blending with other acids and / or salts.
炭酸化に際しては、反応槽の底部にガス吹き込み口を設けるとともに、槽内のｐＨを測定するｐＨ計を設け、バッチ処理で、スラリーのｐＨが所定の値以下になるまで槽中のスラリーに対してガスを吹き込むことで実施することが出来る。また、ＶＦポンプのような歯車が噛み合う部分にガス吹き込み口を設け、スラリーに対して粉砕とガスの吹き込みを同時に実施することが出来る。 During carbonation, a gas blowing port is provided at the bottom of the reaction tank, and a pH meter for measuring the pH in the tank is provided, and batch processing is performed on the slurry in the tank until the pH of the slurry falls below a predetermined value. This can be done by blowing gas. Further, a gas blowing port is provided in a portion where the gears such as a VF pump mesh with each other, and pulverization and gas blowing can be simultaneously performed on the slurry.
炭酸化のための二酸化炭素としては、ＣＯ２分離工程として、例えばＰＳＡ型分離装置等の二酸化炭素分離装置を用いて排ガスから二酸化炭素を分離して用いることができる。また、排ガスを直接利用したり、市販の二酸化炭素ガスを利用、併用したりすることもできる。 As carbon dioxide for carbonation, carbon dioxide can be separated from exhaust gas using a carbon dioxide separator such as a PSA separator in the CO 2 separation step. Moreover, exhaust gas can be used directly, or commercially available carbon dioxide gas can be used and used together.
二酸化炭素の吹き込み速度は、一定とすることも、また可変とすることも可能であり、可変とする場合、ｐＨの推移に応じて適宜調整すること等ができる。 The blowing rate of carbon dioxide can be constant or variable, and in the case of being variable, it can be appropriately adjusted according to the transition of pH.
本形態において、再生粒子のいっそうの品質安定化を図るためには、被処理物の粒子径を、各工程で均一に揃えるための分級を行うことが好ましく、粗大や微小粒子を前工程にフィードバックすることで、より品質の安定化を図ることができる。 In this embodiment, in order to further stabilize the quality of the regenerated particles, it is preferable to classify the particle diameter of the object to be processed uniformly in each process, and feed back coarse and fine particles to the previous process. By doing so, quality can be further stabilized.
また、乾燥工程の前段階において、脱水処理を行った脱墨フロス（脱水物）を造粒することが好ましく、更には造粒物の粒子径を均一に揃えるための分級を行うことがより好ましく、粗大や微小の造粒粒子を前工程にフィードバックすることでより品質の安定化を図ることができる。造粒においては、公知の造粒設備を使用できるが、回転式、攪拌式、押し出し式等の設備が好適である。 In addition, it is preferable to granulate the deinked floss (dehydrated product) that has been subjected to dehydration in the previous stage of the drying process, and it is more preferable to classify the granulated product to make the particle size uniform. The quality can be further stabilized by feeding back coarse and fine granulated particles to the previous process. In granulation, known granulation equipment can be used, but equipment such as a rotary type, a stirring type, and an extrusion type is suitable.
以下、合成例及び実施例によって本発明をさらに詳細に説明するが、本発明はこれらの実施例に限定されるものではない。 EXAMPLES Hereinafter, although a synthesis example and an Example demonstrate this invention further in detail, this invention is not limited to these Examples.
なお、本実施例における各測定値は、以下の方法にて測定した値である。 In addition, each measured value in a present Example is a value measured with the following method.
［平均粒子径（μｍ）］
レーザー回折粒度分布測定装置〔マイクロトラック／日機装社〕（型番：ＭＴ−３３００）を使用し、体積平均粒子径（Ｄ５０：μｍ）を測定した。測定試料の調製は、０．１％ヘキサメタ燐酸ソーダ水溶液に粒子を添加し、超音波で１分間分散した。
[Average particle size (μm)]
A volume average particle diameter (D 50 : μm) was measured using a laser diffraction particle size distribution measuring device [Microtrack / Nikkiso Co., Ltd.] (model number: MT-3300). In the preparation of the measurement sample, particles were added to a 0.1% sodium hexametaphosphate aqueous solution and dispersed with an ultrasonic wave for 1 minute.
［シリカ被覆率（質量％）］
堀場製作所製のＸ線マイクロアナライザーを用い、加速電圧（１５ＫＶ）にて元素分析を行い、含有する構成成分からクレー、炭酸カルシウム、タルク等の含有割合を推定し、シリカ被覆後のシリカ成分の含有率から、シリカ被覆率（質量％）を算出した。
[Silica coverage (mass%)]
Using an X-ray microanalyzer manufactured by HORIBA, the elemental analysis is performed at an acceleration voltage (15 KV), the content ratio of clay, calcium carbonate, talc, etc. is estimated from the contained components, and the silica component after silica coating is contained From the rate, the silica coverage (mass%) was calculated.
［白色度（％）］
Ｔａｐｐｉ−５３４ｐｍ−７６法に基づいて粒子の白色度を測定した。
[Whiteness (%)]
The whiteness of the particles was measured based on the Tappi-534 pm-76 method.
［吸油度（ｍＬ／１００ｇ）］
ＪＩＳ−Ｋ５１０１記載の練り合わせ法に準じて測定した。すなわち１０５℃〜１１０℃で２時間乾燥した試料２ｇ〜５ｇをガラス板に取り、精製アマニ油（酸価４以下のもの）をビュレットから少量ずつ試料の中央に滴下しその都度ヘラで練り合わせ、滴下練り合わせの操作を繰り返し、全体が初めて１本の棒状にまとまったときを終点として、精製アマニ油の滴下量を求め、下記式（２）によって吸油度を算出した。
吸油度（ｍＬ／１００ｇ）
＝［アマニ油量（ｍＬ）×１００］／紙料（ｇ） ・・・（２）
[Oil absorption (mL / 100g)]
It measured according to the kneading method described in JIS-K5101. That is, 2 g to 5 g of a sample dried at 105 ° C. to 110 ° C. for 2 hours is taken on a glass plate, and refined linseed oil (having an acid value of 4 or less) is dropped from the burette to the center of the sample little by little and kneaded with a spatula each time. The kneading operation was repeated, and the dripping amount of refined linseed oil was determined with the end point when the whole was first assembled into one rod shape, and the oil absorption was calculated by the following formula (2).
Oil absorption (mL / 100g)
= [Look of Linseed Oil (mL) x 100] / Paper (g) (2)
［坪量（ｇ／ｍ２）］
ＪＩＳ−Ｐ８１４２に記載の「紙及び板紙−坪量測定方法」に準拠して測定した。
[Basis weight (g / m 2 )]
It measured based on "Paper and board-Basis weight measuring method" described in JIS-P8142.
［灰分歩留（％）］
手抄で得られた複合粒子内添紙の灰分（ＪＩＳ−Ｐ８２５１に準拠して測定）を、手抄に供した紙料中の灰分で除して算出した。
[Ash yield (%)]
The calculation was performed by dividing the ash content (measured in accordance with JIS-P8251) of the composite particle-added paper obtained by hand-drawing with the ash content in the paper material used for hand-drawing.
［白紙不透明度（％）］
ＪＩＳ−Ｐ８１４９に記載の方法に準拠して測定した。
[Blank Opacity (%)]
It measured based on the method of JIS-P8149.
［印刷後不透明度（％）］
Ｊ．ＴＡＰＰＩ ４５に準拠して新聞用オフセット印刷インキ（墨）を使用し、ＲＩ印刷試験機（明製作所製）でインキ量を変えてベタ印刷を行った。印刷面反射率が９％の時の印刷前の裏面反射率（印刷面の反対面）に対する印刷後の裏面反射率の比率から、下記式（３）を用いて印刷不透明度（Ｙ）を算出した。なお、反射率測定には分光白色度測機（スガ試験機製）を使用した。
Ｙ＝｛（印刷後裏面反射率）／（未印刷の裏面反射率）｝×１００ ・・・（３）
[Opacity after printing (%)]
J. et al. In accordance with TAPPI 45, newspaper offset printing ink (black) was used, and solid printing was performed by changing the amount of ink with an RI printing tester (manufactured by Meisei Seisakusho). From the ratio of the back surface reflectance after printing to the back surface reflectance before printing (opposite side of the printing surface) when the printing surface reflectance is 9%, the printing opacity (Y) is calculated using the following formula (3). did. In addition, the spectral whiteness meter (made by Suga Test Instruments) was used for the reflectance measurement.
Y = {(back surface reflectance after printing) / (unprinted back surface reflectance)} × 100 (3)
〔再生粒子の製造〕
原料として脱墨フロスを用い、水分率が４５質量％、平均粒径が１０ｍｍ、また、５０ｍｍ以下の粒子の割合が９０質量％となるように脱水工程を行った。この脱水物にシャワー水による洗浄を経て、第１熱処理工程、その後、第２熱処理工程を以下の条件で行い熱処理物を得た。
第１熱処理工程条件
燃焼形式：内熱キルン
燃焼温度：５００℃
酸素濃度：１０％
滞留時間：５０分
第２熱処理工程条件
燃焼形式：外熱キルンと内熱キルンの併用
入口の平均粒子径：５ｍｍ
燃焼温度：７００℃
酸素濃度：１４％
滞留時間：１４０分
出口の平均粒子径：５ｍｍ
[Production of regenerated particles]
A deinking floss was used as a raw material, and the dehydration step was performed so that the moisture content was 45 mass%, the average particle size was 10 mm, and the proportion of particles of 50 mm or less was 90 mass%. This dehydrated product was washed with shower water, and the first heat treatment step and then the second heat treatment step were performed under the following conditions to obtain a heat treatment product.
First heat treatment process conditions Combustion type: Internal heat kiln Combustion temperature: 500 ° C
Oxygen concentration: 10%
Residence time: 50 minutes Second heat treatment process conditions Combustion type: Combined use of external and internal heat kilns Average particle diameter at inlet: 5 mm
Combustion temperature: 700 ° C
Oxygen concentration: 14%
Residence time: 140 minutes Average particle diameter at outlet: 5 mm
得られた熱処理物１００質量部に対して、配合・スラリー化工程として、硫酸カルシウム二水和物０．３質量部を添加し、この添加物を水中に懸濁させて、濃度（スラリーの全質量に対する熱処理物の質量比）３５質量％のスラリーを得て、粉砕装置にて粉砕した。この粉砕物を分級し、体積平均粒子径１．０μｍ、２．０μｍ、３．４μｍ、５．０μｍ及び１０．０μｍの再生粒子をそれぞれ得た。 To 100 parts by mass of the obtained heat-treated product, 0.3 parts by mass of calcium sulfate dihydrate is added as a blending / slurry step, and the additive is suspended in water to obtain a concentration (total slurry). A mass of 35% by mass of a heat-treated product with respect to mass was obtained and pulverized with a pulverizer. This pulverized product was classified to obtain regenerated particles having a volume average particle size of 1.0 μm, 2.0 μm, 3.4 μm, 5.0 μm and 10.0 μm, respectively.
＜実施例１＞
上記方法で得られた平均粒子径３．４μｍの再生粒子６０質量部と、平均粒子径０．５μｍの二酸化チタン粒子４０質量部とを水に分散させ、１７．４質量％（固形分濃度）の粒子スラリーを得た。この粒子スラリーに、カチオン性凝集剤（ハイモ社製「ハイモロックＦＲ−７４０」）を１，７５０ｐｐｍ添加し、凝集体スラリーを得た。
<Example 1>
60 parts by mass of regenerated particles having an average particle diameter of 3.4 μm obtained by the above method and 40 parts by mass of titanium dioxide particles having an average particle diameter of 0.5 μm are dispersed in water, and 17.4% by mass (solid content concentration). Particle slurry was obtained. To this particle slurry, 1,750 ppm of a cationic flocculant (“Himoloc FR-740” manufactured by Hymo Co., Ltd.) was added to obtain an aggregate slurry.
上記凝集体スラリーを固形分濃度１０％に調整し、このスラリー２００ｇに珪酸ナトリウム水溶液（５質量％）６０ｇを添加して、ホモミキサーを使用して回転数３，０００ｒｐｍで２０分間、分散処理を行い珪酸ナトリウムを含むスラリーを調製した。次に、このスラリーを攪拌機、温度センサー、還流冷却器の付いた１Ｌの四口フラスコに入れ、攪拌しながら油浴にて８５℃に昇温した。次に容器内のスラリーを８５℃に保ちながら、１規定の硫酸１５０ｍＬを定量ポンプを使用して、滴下速度２．５ｍＬ／分で１００分かけて滴下し、シリカで被覆された複合粒子１を含む複合粒子スラリーを得た。 The aggregate slurry is adjusted to a solid content concentration of 10%, 60 g of sodium silicate aqueous solution (5% by mass) is added to 200 g of the slurry, and dispersion treatment is performed for 20 minutes at 3,000 rpm using a homomixer. A slurry containing sodium silicate was prepared. Next, this slurry was put into a 1 L four-necked flask equipped with a stirrer, a temperature sensor, and a reflux condenser, and heated to 85 ° C. in an oil bath while stirring. Next, while maintaining the slurry in the container at 85 ° C., 150 mL of 1N sulfuric acid was dropped over 100 minutes at a dropping rate of 2.5 mL / min using a metering pump, and the composite particles 1 coated with silica were separated. A composite particle slurry containing was obtained.
得られた複合粒子１のシリカ被覆率は２１質量％、平均粒子径は６．４μｍ、白色度は９４．０％、吸油度は６２ｍＬ／１００ｇであった。 The obtained composite particles 1 had a silica coverage of 21% by mass, an average particle size of 6.4 μm, a whiteness of 94.0%, and an oil absorption of 62 mL / 100 g.
＜実施例２〜１７及び比較例１〜３＞
表１に記載の再生粒子、二酸化チタン粒子、これらの配合比（質量比）、凝集剤及びシリカ被覆における反応条件とした以外は、実施例１と同様にして、実施例２〜１７及び比較例１〜３を行い、複合粒子１〜１７及びｉ〜ｉｉｉを得た。
<Examples 2 to 17 and Comparative Examples 1 to 3>
Examples 2 to 17 and Comparative Example were the same as Example 1 except that the regenerated particles, titanium dioxide particles, the mixing ratio (mass ratio), the flocculant, and the silica coating conditions described in Table 1 were used. 1-3 were performed, and composite particles 1-17 and i-iii were obtained.
なお、実施例７、９及び１７では、凝集後のシリカ被覆を行わなかった。比較例１では再生粒子のみを凝集させた後、シリカ被覆した。比較例２では、再生粒子の代わりに平均粒子径３．０μｍの軽質炭酸カルシウム粒子を用いた。比較例３では、再生粒子と二酸化チタン粒子とを混合したのみで、凝集及びシリカ被覆はどちらも行わなかった。 In Examples 7, 9 and 17, the silica coating after aggregation was not performed. In Comparative Example 1, only the regenerated particles were aggregated and then coated with silica. In Comparative Example 2, light calcium carbonate particles having an average particle diameter of 3.0 μm were used instead of the regenerated particles. In Comparative Example 3, only the regenerated particles and the titanium dioxide particles were mixed, and neither aggregation nor silica coating was performed.
また、用いた表１中の凝集剤は以下のとおりである。
・カチオン性凝集剤：ハイモ社製「ハイモロックＦＲ−７４０」
アクリルアミドとアクリロイルオキシエチルトリメチルアンモニウムクロライドとの共重合体及びポリアルキレンポリアミン混合物
質量平均分子量：８５０万
カチオン電荷密度：８．０ｍｅｑ／ｇ
・アニオン性凝集剤：ハイモ社製「ハイモロックＦＡ２３０」
アクリル酸ナトリウムとアクリルアミドとの共重合体
質量平均分子量：１，４００万
カチオン電荷密度：−４ｍｅｑ／ｇ
The flocculants in Table 1 used are as follows.
Cationic flocculant: “Himoloc FR-740” manufactured by Hymo Corporation
Copolymer of acrylamide and acryloyloxyethyltrimethylammonium chloride and polyalkylene polyamine mixture Weight average molecular weight: 8.5 million Cationic charge density: 8.0 meq / g
Anionic flocculant: “Himolock FA230” manufactured by Hymo
Copolymer of sodium acrylate and acrylamide Mass average molecular weight: 14 million Cationic charge density: -4 meq / g
得られた各複合粒子のシリカ被覆率、平均粒子径、白色度及び吸油度を表１に示す。 Table 1 shows the silica coverage, average particle diameter, whiteness, and oil absorption of each composite particle obtained.
＜実施例１８＞
得られた複合粒子１を用いて、固形分濃度１０％のスラリーを調製した。ＮＢＫＰ（フリーネス＝ＣＳＦ５２０ｍＬ）１０質量部及びＬＢＫＰ（フリーネス＝ＣＳＦ４８０ｍＬ）９０質量部を配合したパルプスラリーに、上記スラリーを固形分で１５質量部、硫酸バンドを０．５質量部、カチオン化澱粉０．７質量部、中性ロジンサイズ剤１．０質量部、歩留向上剤０．１質量部をそれぞれ添加し、固形分濃度０．９質量％の紙料を調製した。この紙料を手抄き抄紙機でパルプシートを作成し、乾燥後、ラボスーパーカレンダーに通紙して、米坪が６４．７ｇ／ｍ２の実施例１８の複合粒子含有紙を得た。
<Example 18>
Using the obtained composite particles 1, a slurry having a solid content concentration of 10% was prepared. A pulp slurry containing 10 parts by mass of NBKP (freeness = CSF 520 mL) and 90 parts by mass of LBKP (freeness = CSF 480 mL) was mixed with 15 parts by mass of the slurry, 0.5 parts by mass of sulfuric acid band, 0. 7 parts by mass, 1.0 part by mass of a neutral rosin sizing agent, and 0.1 part by mass of a yield improver were added to prepare a paper material having a solid content concentration of 0.9% by mass. The paper stock was hand-made, a pulp sheet was prepared with a paper machine, dried, and then passed through a lab super calendar to obtain a composite particle-containing paper of Example 18 having a rice basis weight of 64.7 g / m 2 .
＜実施例１９〜３４及び比較例４〜６＞
用いた複合粒子を表２に示すものにした以外は、実施例１８と同様の操作を行い、実施例１９〜３４及び比較例４〜６の各複合粒子内添紙を得た。
<Examples 19 to 34 and Comparative Examples 4 to 6>
Except that the composite particles used were those shown in Table 2, the same operations as in Example 18 were performed to obtain each composite particle-added paper of Examples 19 to 34 and Comparative Examples 4 to 6.
得られた各複合粒子内添紙の坪量、灰分歩留、白紙不透明度及び印刷後不透明度を表２に示す。 Table 2 shows the basis weight, ash yield, blank paper opacity, and post-print opacity of each composite particle-containing paper obtained.
＜実施例３５＞
顔料として、複合粒子１を２０質量部、炭酸カルシウム粒子（ハイドロカーブ＃９０：オミヤ社）４０質量部及びカオリン（ＨＦ−９０：ヒューバー社）２０質量部、ＳＢＲラテックス（ＰＡ４０９８：日本Ａ＆Ｌ社）１１質量部、澱粉（スターコート：日本食品加工社）２質量部並びに分散剤（アロンＡ−６０２８：東亜合成化学工業）０．３質量部を水に配合し、コーレスミキサーでスラリー化し、固形分５０質量％の塗工液を調製した。
<Example 35>
As pigments, 20 parts by mass of composite particles 1, 40 parts by mass of calcium carbonate particles (Hydrocurve # 90: Omiya) and 20 parts by mass of kaolin (HF-90: Huber), SBR latex (PA4098: Japan A & L) 11 Part by weight, 2 parts by weight of starch (star coat: Nippon Food Processing Co., Ltd.) and 0.3 parts by weight of a dispersant (Aron A-6028: Toa Gosei Chemical Industry) are mixed in water, slurried with a Coreless mixer, and a solid content of 50 A mass% coating solution was prepared.
この塗工液を坪量４１．５ｇ／ｍ２の上質原紙の片面に乾燥質量６．８ｇ／ｍ２となるように片面ずつロールテストコーターで塗工し、その後乾燥及びさらにテストスーパーカレンダ仕上げ（線圧１６０ｋｇ／ｃｍ×２回通紙）して塗工紙を得た。 The coating liquid was coated by a roll test coater each side as one side of fine base paper having a basis weight of 41.5 g / m 2 a dry weight 6.8 g / m 2, then dried and further testing supercalendered ( A linear pressure of 160 kg / cm × 2 passes through) to obtain a coated paper.
＜実施例３６及び３７並びに比較例７及び８＞
複合粒子１のかわりに表３に示す各複合粒子を用い、表３の塗工量としたこと以外は、実施例３５と同様の操作を行い、実施例３６及び３７並びに比較例７及び８の各塗工紙を得た。
<Examples 36 and 37 and Comparative Examples 7 and 8>
Each composite particle shown in Table 3 was used in place of the composite particle 1, and the same operation as in Example 35 was performed except that the coating amount in Table 3 was used, and Examples 36 and 37 and Comparative Examples 7 and 8 Each coated paper was obtained.
得られた各塗工紙の不透明度及び印刷不透明度を表３に示す。 Table 3 shows the opacity and printing opacity of each coated paper obtained.
表２及び表３の結果から、本発明の複合粒子が内添された複合粒子内添紙及び本発明の複合粒子が塗布された塗工紙は、優れた不透明度及び印刷後不透明度を有することがわかる。また、表２の結果から、本発明の複合粒子は高い歩留まり性及び白色度を有することが分かる。 From the results of Tables 2 and 3, the composite particle-containing paper with the composite particles of the present invention internally added and the coated paper coated with the composite particles of the present invention have excellent opacity and post-print opacity. I understand that. Moreover, it turns out that the composite particle of this invention has high yield property and whiteness from the result of Table 2.
本発明の複合粒子は、製紙における内添填料や塗工液における顔料として好適に用いることができる。 The composite particles of the present invention can be suitably used as an internal filler in papermaking or a pigment in a coating solution.
Claims (7)
二酸化チタン粒子と
が凝集剤にて凝集されてなる複合粒子。 Paper sludge as the main raw material, regenerated particles obtained through dehydration, heat treatment and pulverization process,
Composite particles obtained by agglomerating titanium dioxide particles with an aggregating agent.
上記二酸化チタン粒子の平均粒子径が０．２μｍ以上１μｍ以下である請求項１から請求項４のいずれか１項に記載の複合粒子。 The average particle diameter of the regenerated particles is 1 μm or more and 10 μm or less,
The composite particle according to any one of claims 1 to 4, wherein an average particle diameter of the titanium dioxide particles is 0.2 µm or more and 1 µm or less.
上記塗工層が請求項１から請求項５のいずれか１項に記載の複合粒子を含有することを特徴とする塗工紙。 A coated paper having a base paper and one or more coating layers formed on at least one surface of the base paper,
A coated paper, wherein the coated layer contains the composite particles according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010273003A JP5587154B2 (en) | 2010-12-07 | 2010-12-07 | Composite particles, composite particle internal paper and coated paper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010273003A JP5587154B2 (en) | 2010-12-07 | 2010-12-07 | Composite particles, composite particle internal paper and coated paper |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2012121752A JP2012121752A (en) | 2012-06-28 |
| JP5587154B2 true JP5587154B2 (en) | 2014-09-10 |
Family
ID=46503626
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2010273003A Expired - Fee Related JP5587154B2 (en) | 2010-12-07 | 2010-12-07 | Composite particles, composite particle internal paper and coated paper |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5587154B2 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0693204A (en) * | 1992-09-10 | 1994-04-05 | Nittetsu Mining Co Ltd | Production of highly masking white pigment |
| JPH1025696A (en) * | 1996-07-09 | 1998-01-27 | Moruza Kk | Photocatalyst-containing sheet and its production |
| JP3898007B2 (en) * | 2001-07-31 | 2007-03-28 | 日本製紙株式会社 | Method for producing bulky paper with internal filler added with filler, which is an aggregate of inorganic particles and silica composite particles |
| JP2004018336A (en) * | 2002-06-19 | 2004-01-22 | Nippon Paper Industries Co Ltd | Method of manufacturing titanium oxide composite particle and method of manufacturing paper with filler added therein |
| JP4087431B2 (en) * | 2006-08-31 | 2008-05-21 | 大王製紙株式会社 | Method for producing silica-coated regenerated particles, silica-coated regenerated particles, internal paper and coated paper using the same |
| JP2008144347A (en) * | 2008-01-07 | 2008-06-26 | Oji Paper Co Ltd | Filled paper and method for producing the same |
| JP2010236129A (en) * | 2009-03-31 | 2010-10-21 | Daio Paper Corp | Paper filled with heavy calcium carbonate |
-
2010
- 2010-12-07 JP JP2010273003A patent/JP5587154B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2012121752A (en) | 2012-06-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4087431B2 (en) | Method for producing silica-coated regenerated particles, silica-coated regenerated particles, internal paper and coated paper using the same | |
| JP4239034B2 (en) | Manufacturing method of inorganic particles and manufacturing plant thereof | |
| JP4020942B1 (en) | Newspaper | |
| JP4952540B2 (en) | Coated paper for gravure printing | |
| JP4020947B1 (en) | Recycled particle agglomerated paper | |
| JP2004176208A (en) | Method for producing filler from waste water-treated sludge in coated paper-producing process, and paper filled with the same | |
| JP5695875B2 (en) | COMPOSITE PARTICLES, COMPOSITE PARTICLE MANUFACTURING METHOD, COMPOSITE PARTICLE ADDITIVE PAPER AND COATING | |
| JP4928317B2 (en) | Printing paper | |
| JP5702590B2 (en) | Composite particles, composite particle internal paper and coated paper | |
| JP5587154B2 (en) | Composite particles, composite particle internal paper and coated paper | |
| JP2008163515A (en) | Regenerated particle aggregate-added paper and method for producing the same | |
| JP5925985B2 (en) | Paper manufacturing method | |
| JP5661385B2 (en) | Printing paper manufacturing method and printing paper obtained by this manufacturing method | |
| JP5946672B2 (en) | Newspaper | |
| JP5894778B2 (en) | Paper manufacturing method | |
| JP2010236112A (en) | Newsprint paper | |
| JP5502556B2 (en) | Method for producing silica composite particles | |
| JP5683206B2 (en) | Paper making method and paper | |
| JP2012255230A (en) | Printing paper | |
| JP2012188468A (en) | Method for producing composite particle, composite particle, composite particle-internally added paper, and coated paper | |
| JP5855480B2 (en) | Method for producing composite particles | |
| JP5882029B2 (en) | Paper manufacturing method | |
| JP2012117177A (en) | Newsprint paper | |
| JP4831163B2 (en) | Method for producing coated paper | |
| JP2013036133A (en) | Coated paper |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20131122 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20140715 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20140716 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20140723 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 5587154 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |