JP5288062B2 - Non-coated paper and coated paper - Google Patents

Abstract

Provided are: a non-coated paper which contains a monovalent straight-chain alcohol having a number of carbon atoms selected from the group consisting of 24, 26 and 28 and a straight-chain fatty acid having a number of carbon atoms selected from the group consisting of 24, 26 and 28 in a total amount of 100 to 2000ppm and in which the total amount of the straight-chain alcohol and straight-chain fatty acid present on the surface is 15 or less as determined with a time-of-flight secondary ion mass spectrometer; and a coated paper which contains, in the base paper, as much as 100 to 2000ppm of compounds which can hinder interfiber bonding and which can achieve a low moisture content of paper. The compounds are, for example, long-chain fatty acids and/or higher alcohols, particularly, a monovalent straight-chain alcohol having a number of carbon atoms selected from the group consisting of 24, 26 and 28 and a straight-chain fatty acid having a number of carbon atoms selected from the group consisting of 24, 26 and 28.

Description

  The present invention relates to a non-coated paper used for electrophotography or ink-jet applications in, for example, a copying machine or a printer. The present invention also relates to non-coated paper used for printing applications such as offset printing.

  Furthermore, the present invention relates to a coated paper containing a large amount of a compound that inhibits interfiber bonding such as long chain fatty acids and higher alcohols and has a low water content in the paper. More specifically, the present invention can reduce the occurrence of off-roll wrinkles that tend to occur in the post-printing drying process during offset rotary printing, and has excellent dimensional stability. It is related with the coated paper which suppressed generation | occurrence | production of the curl which tends to generate | occur | produce.

  This application claims priority based on Japanese Patent Application No. 2011-162104 filed in Japan on July 25, 2011 and Japanese Patent Application No. 2011-226301 filed in Japan on October 14, 2011, and the contents thereof. Is hereby incorporated by reference.

  In order to use a lignocellulosic material as a papermaking raw material, it is necessary to digest this into a chemical pulp, or mechanically process it using a refiner or the like to obtain a mechanical pulp. These pulps are bleached as desired, adjusted to a desired whiteness, and then used as a papermaking raw material. At present, the chemical pulping method is mainly used because it is easy to adjust to the desired whiteness or pulp characteristics, and in particular, the cooking method called the kraft method can regenerate chemicals and has few restrictions on the raw materials used. For the reason, it has become the mainstream of chemical pulping.

  Specifically, when wood is used as a papermaking raw material, wood chips are first pulped by a cooking process such as a kraft method, and subjected to multistage bleaching to obtain bleached pulp. Conventionally, chlorine bleaching chemicals such as molecular chlorine (C), hypochlorite (H), and / or chlorine dioxide (D) have been widely used for bleaching paper pulp, especially molecular chlorine. Has been particularly preferred because of its high bleaching action and low reactivity with cellulose which affects pulp strength. In addition, in order to increase the bleaching efficiency, the sequence of CEHD or C / DEHED (C / D is a bleaching stage in which chlorine and chlorine dioxide are used together, E is an alkali extraction stage) As described above, pulp bleaching is generally performed in multiple stages, but it has been customary to use molecular chlorine in the first stage where the most amount of bleaching chemicals is used.

  However, since these chlorine bleaching chemicals by-produce organic chlorine compounds that are harmful to the environment during bleaching, there is an increasing trend to reduce the amount of chlorine chemicals used. In particular, when a pulp is bleached with molecular chlorine, a lot of organic chlorine compounds are produced. Therefore, in consideration of the influence on the environment, switching to a bleaching method not using molecular chlorine is increasing. Pulp bleached without using molecular chlorine is called ECF (elementary chlorin-free) pulp, and pulp produced without using any chlorinated chemicals is called TCF (totally chlorin-free). Recognized as an environmentally friendly pulp, ECF pulp has become common in bleached pulp for papermaking.

  When paper is manufactured using the bleached pulp obtained in this way, it is known that the dimensional stability and static friction coefficient of the resulting paper vary greatly depending on the type of pulp used.

  Paper with poor dimensional stability, that is, with a high expansion / contraction rate, was fed to a copier or printer as electrophotographic paper immediately after opening the wrapping paper that wrapped the paper, or in a high-temperature and high-humidity environment. In this case, wrinkles tend to occur frequently immediately after copying or immediately after printing.

Also, uncoated paper with a coefficient of static friction that is too large or too small is used when paper is used as an electrophotographic or inkjet paper in a copying machine or printer. A phenomenon of feeding sheets or more), paper jams, paper empty feeding (a phenomenon in which the paper is not fed into the machine), or misfolding. The causes of such running failure include insufficient paper rigidity, paper curl, static electricity, etc., but the influence of the static friction coefficient of the paper is particularly large.
For example, when paper with a low coefficient of static friction is opened, the paper that wraps the paper is opened, fed to a copier or a printer, and then multiple feeds or idle feeds occur frequently immediately after copying or immediately after printing. Cheap.

  As described above, the dimensional stability and static friction coefficient of paper have a great influence on the performance of paper as an electrophotographic or inkjet paper. Conventionally, however, the dimensional stability is good and the static friction coefficient is controlled to be constant. No paper was found. In particular, paper made from acacia pulp and the like has a high content of long-chain fatty acids and higher aliphatic alcohols, and the static friction coefficient tends to be small. Therefore, Patent Documents 1 and 2 are technologies that prevent the static friction coefficient from becoming too small by using a pulp in which long-chain fatty acids and higher aliphatic alcohols are reduced, and obtain paper with reduced running failure. It is described in. As a method for reducing long-chain fatty acids and higher aliphatic alcohols, Patent Document 1 discloses a technique for subjecting unbleached pulp to a surfactant and then multi-stage bleaching, and Patent Document 2 discloses multi-stage bleaching. Discloses a technique for performing a specific amount of ozone treatment.

In recent years, the printing industry has shifted from an offset sheet-fed printing method (hereinafter referred to as sheet-fed printing) to an offset rotary printing method (hereinafter referred to as off-wheel printing) with labor saving and speeding up. . The off-ring printing has a higher printing speed and can save labor in the post-process, so that the productivity is much higher than the sheet-fed printing.
However, off-wheel printing has several quality problems that are not seen in sheet-fed printing because hot air drying is performed immediately after printing. Among them, the most important and difficult problem to solve is off-wheel wrinkles (sometimes referred to as elbows in the printing industry), and the drying shrinkage of the image area and non-image area in the drying process of off-wheel printing. A mechanism for wrinkling due to the difference in rate has been proposed.

  For this reason, attempts have been made to reduce off-line wrinkles. For example, the freeness of the pulp constituting the base paper is maintained within a specific range, and the air permeability of the base paper is controlled to a region where the specific air permeability is good. And the method (patent document 3) which suppresses generation | occurrence | production of an off ring wrinkle is proposed. However, since coated paper for off-wheel printing is produced through a series of processes such as pulp preparation, papermaking, coating, and pressurizing with a calendar, it simply involves the freeness of pulp and the transparency of the base paper. Just adjusting the temper will not solve the wrinkle off sufficiently.

  Also defined by the ratio of the maximum and minimum values of the microwave transmission intensity of the base paper by the microwave method, the Fenchell immersion elongation in the direction perpendicular to the paper making direction, and the value obtained by dividing the air permeability by the paper thickness. Means for eliminating off-wrinkles by using base paper have also been proposed (Patent Document 4). However, since the cause of off-roll wrinkles is not only the fiber orientation of the base paper, a satisfactory effect cannot be obtained.

  Moreover, the freeness of hardwood pulp having a lumen width (L) to fiber width (D) ratio L / D of 0.15 to 0.35 is set to 200 to 350 ml, and this is blended in an amount of 10 to 35 mass% of the total pulp. Although a method for suppressing off-wrinkle has also been proposed (Patent Document 5), since such a pulp has a rigid fiber and a square shape and is large in shape, sufficient smoothness can be obtained by calendaring. There is a difficulty that it is difficult to obtain.

  By providing a polyvinyl alcohol-containing coating layer containing polyvinyl alcohol or polyvinyl alcohol and a pigment as components on a base paper, and providing a pigment coating layer thereon, the drying shrinkage force, air permeability, etc. of the resulting coated paper can be reduced. There has been proposed a coated paper for printing which is adjusted within a specific range and hardly causes off-roll wrinkles, and hardly causes misregistration even in gravure printing or flexographic printing (Patent Document 6). However, with this coated paper for printing, the occurrence of off-roll wrinkles can be greatly reduced or eliminated, but the polyvinyl alcohol-containing coating layer needs to be thickened to some extent, and there is a difficulty in restricting production facilities. is there.

  Furthermore, between the web path behind the dryer exit of the rotary offset printing press, it passes between the heating roll and the pressure roll having a surface free energy of 30 mN / m or less, and the paper is humidified by the dryer. There has also been proposed a method (Patent Document 7) in which elbows are mechanically eliminated on the same principle as a steam iron by replenishing reduced moisture and simultaneously passing between a heating roll and a pressure roll. However, in this method, depending on the depth and number of the generated wrinkles, several wrinkles may be combined and pressed between the rolls, resulting in a defect that greatly impairs the product value.

  In addition to this, a method of reducing off-wrinkles by applying a surface sizing agent or a surface sizing agent and a plastic pigment on the surface of the coating layer of the coated paper (Patent Documents 8 and 9) or offset rotary printing. Containing 0.1 to 10% by mass of a mixture of a cationic fatty acid amide and a nonionic wetting agent relative to the mass of the base paper (Patent Document 10), and a pulp having scale-like external fibrils. A method (Patent Document 11) has also been proposed in which paper with good dimensional stability is obtained by making paper by adding it to a paper stock, but a sufficient effect is not necessarily obtained.

JP 2003-96681 A JP 2003-96682 A JP 58-186700 A Japanese Patent Application Laid-Open No. 06-056786 Japanese Patent Laid-Open No. 10-226979 JP 2000-45199 A JP 2002-347111 A JP 2002-263888 A JP 2004-091986 A JP 2006-291393 A JP 2008-248459 A

  However, the techniques described in Patent Documents 1 and 2 cannot sufficiently control the static friction coefficient of paper. Also, the dimensional stability of the obtained paper was not good.

  The present invention is a paper (non-coated) having a controlled coefficient of static friction, good dimensional stability, and reduced occurrence of running defects and wrinkles when used in electrophotography or inkjet applications in copying machines and printers. (Professional paper) is an issue. Another object of the present invention is to provide paper (non-coated paper) in which the occurrence of curling is suppressed when used for printing applications such as offset printing.

  Furthermore, the present invention can reduce the occurrence of off-roll wrinkles (offsets) during offset rotary printing, has excellent dimensional stability, and suppresses the occurrence of curling that tends to occur after printing during offset sheet-fed printing. Providing industrial paper is an issue.

  As a result of intensive studies to solve the above problems, the present inventors have found that a monovalent straight-chain alcohol having 24, 26, or 28 carbon atoms and a carbon number having 24, 26, or 28 carbon atoms. By controlling the linear fatty acid content of any one of the non-coated papers to a specific amount, the dimensional stability of the paper can be adjusted well, and these linear alcohols and linear fatty acids are not coated. The inventors found that the coefficient of static friction can be adjusted by controlling the abundance on the paper surface to a specific amount, thereby completing the present invention.

  In addition, as a result of intensive studies to solve the above-mentioned problems, the present inventors are coated paper in which at least one coating layer containing a pigment and an adhesive is provided on a base paper, and the carbon is contained in the base paper. Control the content of monovalent linear alcohol having any of 24, 26, or 28 and linear fatty acid having any of 24, 26, or 28 in the base paper to a specific amount. As a result, it was found that the dimensional stability of the coated paper can be adjusted well, curling can be suppressed, and generation of off-ring wrinkles can be reduced, and the present invention has been completed.

The non-coated paper according to one aspect of the present invention includes a monovalent linear alcohol having 24, 26, or 28 carbon atoms and a straight line having any of 24, 26, or 28 carbon atoms. The total content of the chain fatty acid is 215 to 2000 ppm, and the total abundance of the linear alcohol and the linear fatty acid on the surface measured by a time-of-flight secondary ion mass spectrometer is 15 or less. It is characterized by that.
The non-coated paper according to another aspect of the present invention includes calcium carbonate and colloidal silica as long as the ash content measured by the ash content test method (525 ° C. combustion method) described in JIS P 8251: 2003 is 35% by mass or less. And at least one selected from the group consisting of calcined kaolin.
The non-coated paper according to still another aspect of the present invention has a freeness measured according to JIS P 8121: 1995 of disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998. ˜550 ml, JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method specified in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30 to 1.90. It is preferable that
Furthermore, the freeness measured according to JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 350 to 550 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and the fiber length distribution coefficient is 1.30 to 1.60. It is preferable that
The non-coated paper of the present invention preferably has a static friction coefficient of 0.40 to 0.70.

Another aspect of the present invention is a coated paper in which at least one coating layer containing a pigment and an adhesive is provided on a base paper, and has any of 24, 26, or 28 carbon atoms. The total content contained in the base paper of a monovalent linear alcohol and a linear fatty acid having 24, 26, or 28 carbon atoms is 180 to 2000 ppm.
The coated paper according to another aspect of the present invention has a freeness measured in accordance with JIS P 8121-1995 of disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998. 550 ml, JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method specified in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30 to 1.90. It is preferable that
Furthermore, the freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 400-500 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and the fiber length distribution coefficient is 1.30 to 1.60. It is preferable that

That is, the present invention relates to the following.
(1) A coated paper comprising at least one coating layer containing a pigment and an adhesive on a base paper, wherein the base paper is selected from the group consisting of 24, 26, and 28 carbon atoms. The total content of the monovalent linear alcohol having carbon number and the linear fatty acid having carbon number selected from the group consisting of 24, 26, and 28 is 180 to the mass of the whole base paper Coated paper which is 2000ppm,
(2) The coated paper according to (1), which is for offset printing,
(3) The freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 380-550 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30. The coated paper according to (1) or (2) , which is ˜1.90,
(4) The freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 400-500 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and the fiber length distribution coefficient is 1.30. The coated paper according to any one of (1) to (3), which is ˜1.60, and (5) a carbon number selected from the group consisting of 24, 26, and 28. The total content of the linear alcohol having a valence and the linear fatty acid having a carbon number selected from the group consisting of 24, 26, and 28 is 215 to 2000 ppm based on the mass of the entire paper, And the non-coated paper whose total amount of the said linear alcohol and the said linear fatty acid of the surface measured with the time of flight secondary ion mass spectrometer is 15 or less,
(6) Non-coated paper according to (5), which is for sheet feeding.
(7) The non-coated paper according to (5) or (6), which is used for electrophotography or inkjet,
(8) selected from the group consisting of calcium carbonate, colloidal silica, and calcined kaolin within a range in which the ash content measured by the ash test method (525 ° C. combustion method) described in JIS P 8251: 2003 is 35% by mass or less The non-coated paper according to any one of (5) to (7), which contains at least one substance,
(9) The freeness measured according to JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 380 to 550 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30. The non-coated paper according to any one of (5) to (8), which is ˜1.90,
(10) The freeness measured according to JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 350 to 550 ml, and JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and the fiber length distribution coefficient is 1.30. Uncoated paper as described in any one of (5)-(8) which is -1.60,
(11) The non-coated paper according to any one of (5) to (10) , wherein the static friction coefficient is 0.40 to 0.70.

  According to one aspect of the present invention, paper (non-coated) having a controlled coefficient of static friction, good dimensional stability, and reduced occurrence of running defects and wrinkles when used in a copier or printer. Paper). Further, according to another aspect of the present invention, it is possible to provide a paper (non-coated paper) in which the occurrence of curling is suppressed when used for printing applications such as offset printing.

  Furthermore, according to another aspect of the present invention, when used in an offset rotary printing press, the occurrence of off-roll wrinkles is reduced, the dimensional stability is good, and the occurrence of post-printing during offset sheet-fed printing. It is possible to provide a coated paper that suppresses the occurrence of curls.

The non-coated paper according to the first aspect of the present invention is a monovalent linear alcohol having at least one carbon number selected from the group consisting of 24, 26, and 28 (hereinafter, linear alcohol). (In some cases, it is referred to as (A).) And a linear fatty acid having at least one carbon number selected from the group consisting of 24, 26, and 28 (hereinafter referred to as linear fatty acid (B)). The total content contained in the whole paper is 100 to 2000 ppm with respect to the mass of the whole paper, and the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper And the total abundance is controlled to 15 or less.
The total abundance of the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper is measured with a time-of-flight secondary ion mass spectrometer (hereinafter sometimes referred to as TOF-SIMS). Value.
In plants, since alcohol and fatty acids are generally synthesized using acetic acid as a starting material, the synthesized alcohols and fatty acids have an even number of carbon atoms.

When the total content of the linear alcohol (A) and the linear fatty acid (B) in the non-coated paper is 100 ppm or more with respect to the total mass of the non-coated paper, the water repellency of the pulp fibers is improved and the paper The moisture content can be reduced and the dimensional stability is improved. In addition, the linear alcohol (A) and the linear fatty acid (B) inhibit the interfiber bond of the paper and loosen the interfiber bond, so that the expansion and contraction of the paper can be suppressed even when the moisture in the environment changes. Dimensional stability can be maintained well. Further, curling is less likely to occur. Therefore, the occurrence of wrinkles is suppressed immediately after opening the wrapping paper that is wrapping non-coated paper, or when it is fed to a copier or printer as electrophotographic paper in a high temperature and high humidity environment. The
On the other hand, when the total content of the linear alcohol (A) and the linear fatty acid (B) in the non-coated paper is 2000 ppm or less with respect to the mass of the entire non-coated paper, There are no drawbacks. Here, paper has a defect such as dust (a straight-chain alcohol or straight-chain fatty acid hardens and appears as black or brown spots, and in some cases, transparent spots).
The total content of the linear alcohol (A) and the linear fatty acid (B) is preferably 300 ppm or more, more preferably 500 ppm or more, and still more preferably 700 ppm or more with respect to the mass of the whole uncoated paper.
The range of the total content of the linear alcohol (A) and the linear fatty acid (B) is preferably 300 to 2000 ppm, more preferably 500 to 2000 ppm, and still more preferably 700 to 2000, based on the total mass of the non-coated paper. .

When the total abundance of the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper measured by a time-of-flight secondary ion mass spectrometer is 15 or less, the static friction of the non-coated paper The coefficient does not become too low, and as a result, running failures such as idle feeding, paper jams, and double feeding in a copying machine or printer are suppressed.
The total amount of the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper of the present invention is preferably 0.5 to 15, more preferably 0.5 to 10. . If the lower limit value is 0.5 or more, the static friction coefficient of the non-coated paper does not become too high, and there is a tendency that running failures such as idling, paper jam, or double feeding due to the high static friction coefficient can be further suppressed. .

The total content of the linear alcohol (A) and the linear fatty acid (B) in the entire paper is appropriately selected from pulp raw materials (hardwood, softwood, non-wood pulp fiber chips, waste paper, waste paper, etc.) Cooking step for cooking the raw materials (including washing in the cooking step); Bleaching step for unbleached pulp obtained by cooking (including washing and dehydration in the bleaching step); or Beating the obtained bleached pulp It can adjust by controlling each process, such as a papermaking process after having performed.
On the other hand, the total abundance of the linear alcohol (A) and the linear fatty acid (B) on the paper surface is at least one substance selected from the group consisting of calcium carbonate, colloidal silica, and calcined kaolin in the paper making process. It can be controlled by adjusting the content of the non-coated paper, for example, by adding it to the paper stock. When calcium carbonate, colloidal silica, or calcined kaolin is contained in the non-coated paper, the linear alcohol (A) and the linear fatty acid (B) are adsorbed on these, and as a result, it is difficult to exist on the paper surface. It is thought that the total abundance of these on the surface is reduced.

The second aspect of the present invention is a coated paper in which at least one coating layer containing a pigment and an adhesive is provided on the base paper, and the base paper has 24, 26, and 28 carbon atoms. A monovalent linear alcohol having at least one carbon number selected from the group (hereinafter sometimes referred to as linear alcohol (A)) and a group having 24, 26, and 28 carbon atoms. It is necessary to control the total content of linear fatty acids (hereinafter sometimes referred to as linear fatty acids (B)) having at least one carbon number to be 100 to 2000 ppm based on the mass of the base paper. is there.
In plants, since alcohol and fatty acids are generally synthesized using acetic acid as a starting material, the synthesized alcohols and fatty acids have an even number of carbon atoms.
The linear alcohol (A) and the linear fatty acid (B) according to the second aspect of the present invention are synonymous with the linear alcohol (A) and the linear fatty acid (B) according to the first aspect.

The linear alcohol (A) and the linear fatty acid (B) improve the water repellency of the pulp fiber, reduce the moisture content of the paper, improve the dimensional stability, and lower the equilibrium moisture of the paper. In addition, the linear alcohol (A) and the linear fatty acid (B) inhibit the interfiber bond of the paper and loosen the interfiber bond, so that the expansion and contraction of the paper can be suppressed even when the moisture in the environment changes. Dimensional stability can be maintained well. Further, curling is less likely to occur. Therefore, drying shrinkage is suppressed during heat drying in offset rotary printing, and the occurrence of off-roll wrinkles is reduced.
When the total content of the linear alcohol (A) and the linear fatty acid (B) is less than 100 ppm with respect to the mass of the whole base paper, the moisture content of the paper becomes too high, and the dimensional stability due to moisture change in the environment. Is insufficient. Moreover, curling generation is also insufficient. Furthermore, the occurrence of off-roll wrinkles becomes a problem during heat drying in offset rotary printing.
On the other hand, when the total content of the straight chain alcohol (A) and the straight chain fatty acid (B) exceeds 2000 ppm with respect to the mass of the whole base paper, a paper defect due to the inclusion of a large amount thereof occurs. Here, paper has a defect such as dust (a straight-chain alcohol or straight-chain fatty acid hardens and appears as black or brown spots, and in some cases, transparent spots).
The total content of the linear alcohol (A) and the linear fatty acid (B) is preferably 300 to 1800 ppm, more preferably 500 to 1500 ppm, based on the mass of the entire base paper.

  The total content of the linear alcohol (A) and the linear fatty acid (B) in the base paper is appropriately selected from pulp raw materials (hardwood, conifer, non-wood pulp fiber chips, waste paper, waste paper, etc.) Cooking process to digest raw materials (including washing in cooking process); bleaching process of unbleached pulp obtained by cooking (including washing and dehydration in bleaching process); or after beating the obtained bleached pulp It can be adjusted by controlling each process such as a papermaking process.

Hereinafter, the method for producing the non-coated paper and the coated paper of the present invention will be described.
(Pulp raw materials)
The raw material of the pulp used for the production of the non-coated paper and the coated paper of the present invention may be any of hardwood, softwood and non-wood pulp fiber, and two or more kinds of raw materials may be used in combination. It is preferable to use a hardwood material containing at least a relatively large amount of the linear alcohol (A) and the linear fatty acid (B) from the viewpoint of easily obtaining the non-coated paper and the coated paper of the present invention.

  Although it does not specifically limit as a broad-leaved tree, Among them, as a tree species which contains many linear alcohol (A) and a linear fatty acid (B), Acacia mangium (Acacia mangum), A., and so on. auriculiformis (Acacia auricularis), A. catchu (Acacia catechu), A.C. decurrens, A.A. holoserica (Acacia holosericia), A.I. leptocarpa (Acacia leptocarpa), A. Maidenii (Acacia Maidenii), A. mearnsii (Acacia merancy), A.M. melanoxylon (acacia melanoxylone), A.I. nerifolia (Acacia nellifora), A.N. silvertris (Acacia squirrel), or A. peregrinalis (Acacia peregrinalis) and the like, and hybrids of these hybrids (hybrid: hybrid) are mentioned, and it is preferable to use at least one of these species.

The blending amount of the hardwood, especially acacia wood, is preferably 30% by mass or more based on the mass of the whole pulp raw material. When the content is less than 30% by mass, the total content of the linear alcohol (A) and the linear fatty acid (B) contained in the base paper, which is a feature of the present invention, is 100 ppm relative to the total mass of the paper or the total mass of the base paper. The moisture content of the paper becomes too high, and the dimensional stability due to moisture changes in the environment becomes insufficient. Moreover, curling generation is also insufficient. Furthermore, the occurrence of off-roll wrinkles becomes a problem during heat drying in offset rotary printing.
The range of the amount of the acacia wood is preferably 30 to 100%, more preferably 30 to 90%, still more preferably 30 to 70% with respect to the mass of the whole pulp raw material.

Among the broad-leaved trees, other usable tree species include Eucalyptus camaldulensis (Eucalica maldorensis), E. coli. deglupta (eucalyptus degrupta), E.I. globulus, Eucalyptus globulus. grandis (eucalyptus grandis), E.I. maculata (eucalyptus maculata), E. coli. punctata (Eucalypanthata), E.C. saligna (Eucalis saligna), E.I. tereticornis (Eucali Telenicornis), E.I. urophylla (eucalyptus eurofira), A.M. auracocarpa (Acacia auracocarpa), or A. Examples thereof include a classiccarpa and a hybrid (hybrid) of these.
“A.” stands for acacia and “E.” stands for eucalyptus.

  Although it does not specifically limit as a softwood material, Spruce or vines, such as White Spruce (White Spruce), Black Spruce (Black Spruce), or Hemlock (Hemlock), White Fir (White Fur), Douglas Fir (Douglas Fir) Or fir trees such as Balsam Fir (Balsumfar), poplar trees such as Aspen (Aspen), Southern Pine, Radiata Pine, Lodgepole Pine, Ellio Pin An pine tree such as Eliot Pine) or a cedar tree such as Red Ceder is preferably used.

Non-wood pulp fibers include bast fibers such as mulberry or mitsumata, leaf fibers such as manila hemp or sisal hemp, seed fiber such as cotton or cotton linter, etc. In view of ease of use, uniformity of quality, price, etc., Manila hemp from the Philippines or Ecuador, which has international marketability, can be suitably used.
Furthermore, waste paper, waste paper, or the like can be used as a pulp raw material.

(Cooking process)
The above-described pulp raw material is subjected to a cooking process in the form of, for example, chips to obtain unbleached pulp.
As the cooking method, known cooking methods such as kraft cooking, polysulfide cooking, soda cooking, or alkali sulfite cooking can be used, but a method of cooking by adding a cooking solution in a divided manner is preferred. By adding the cooking liquor separately, the alkali concentration in the whole cooking can be controlled, and as a result, the total content of the linear alcohol (A) and the linear fatty acid (B) in the unbleached pulp obtained can be adjusted. Specifically, when the alkali concentration of the cooking liquor is increased, the removal amount of the linear alcohol (A) and the linear fatty acid (B) can be increased, and an unbleached pulp whose total content is further reduced can be obtained. . Conversely, when the alkali concentration of the cooking liquor is lowered, the removal amount of the linear alcohol (A) and the linear fatty acid (B) can be reduced.

  The specific cooking method is not particularly limited as long as it is a cooking method in which the cooking liquor can be added in a divided manner, but the kraft cooking method such as the Lo-solids method, the Compact cooking method, or the Kobudomari cooking method, compared with the conventional cooking method, It is preferably used in terms of incidental effects such that the amount of energy used at the time of cooking is small or the bleaching property of the pulp to be produced is good.

Moreover, at the time of washing | cleaning in a digestion process, by changing suitably the ratio of the filtrate water / fresh water used as washing water in a washing machine, linear alcohol (A) and linear fatty acid (B) removed at the time of washing | cleaning The amount can be changed. The filtered water is water that is circulated and used as washing water, and the fresh water is normal water that is not circulated.
Specifically, the amount of linear alcohol (A) and linear fatty acid (B) can be reduced by increasing the proportion of filtered water, and the proportion of straight water (A) can be reduced directly by increasing the proportion of fresh water. The removal amount of chain fatty acid (B) can be increased. Therefore, when the chip | tip with comparatively little content of a linear alcohol (A) and a linear fatty acid (B) is used as a pulp raw material, the ratio of the filtration water in a wash water is raised, and a linear alcohol (A) And a formula such that the straight chain fatty acid (B) is not removed so much.
Further, by increasing the temperature of the washing water, the removal amount of the linear alcohol (A) and the linear fatty acid (B) can be increased, and by reducing the temperature of the washing water, the linear alcohol (A) And the amount of linear fatty acid (B) removed can be reduced.

As other digestion process conditions, known conditions can be employed.
For example, when the kraft cooking method is used, the degree of sulfidation of the cooking liquor is 5 to 75%, preferably 15 to 45%, and the effective alkali addition rate is 5 to 30% by weight, preferably 10 to 25% by weight, based on the mass of absolutely dry wood. The cooking temperature is 130 to 170 ° C., and the cooking method may be either a continuous cooking method or a batch cooking method.
In addition, in the cooking, a cyclic keto compound known as a cooking aid in the cooking solution to be used, for example, benzoquinone, naphthoquinone, anthraquinone, anthrone, phenanthroquinone and a nuclear substitution product such as alkyl or amino of the quinone compound; 1 selected from hydroquinone-based compounds such as anthrahydroquinone, which is a reduced form of the above-mentioned compounds; and 9,10-diketohydroanthracene compounds that are stable compounds obtained as intermediates in the anthraquinone synthesis method by the Diels-Alder method Seeds or two or more cooking aids may be added, and the addition rate is 0.001 to 1.0 mass% per the absolute dry mass of the material.

(Bleaching process)
The unbleached pulp obtained by the cooking process is appropriately subjected to rough selection and selection, and then the bleaching process is performed.
Examples of the bleaching step include a method in which an alkali oxygen bleaching method and multi-stage bleaching are sequentially performed, washing is performed between these bleaches, and washing and dehydration are performed after the last bleaching.
And the linear alcohol (A) and the linear fatty acid (B) removed at the time of these washing | cleaning and dehydration by changing suitably the ratio of the filtered water / fresh water of water used for each washing | cleaning and dehydration in a bleaching process. The amount of can be changed. The filtered water is water that is circulated and the fresh water is normal water that is not circulated.
Specifically, by increasing the proportion of fresh water, the removal amount of linear alcohol (A) and linear fatty acid (B) is increased, and the total content of linear alcohol (A) and linear fatty acid (B) is contained. The amount can be reduced. On the contrary, the removal amount of linear alcohol (A) and linear fatty acid (B) can be decreased by increasing the ratio of filtrate water. Moreover, the removal amount of the linear alcohol (A) and the linear fatty acid (B) can be increased by increasing the temperature of the water used, and the linear alcohol (A) and the linear fatty acid can be increased by decreasing the temperature. The removal amount of (B) can be reduced. For example, when it is desired to keep the removal amount of the linear alcohol (A) and the linear fatty acid (B) low, a prescription such as lowering the temperature of the washing water used in the alkali oxygen bleaching method may be adopted.
Moreover, the removal amount of a linear alcohol (A) and a linear fatty acid (B) can be increased in a bleaching process by making high the density | concentration of the alkali used at a bleaching process.

As other conditions for the bleaching step, known conditions can be adopted.
For example, in the bleaching step, first, delignification is performed by the alkaline oxygen bleaching method as described above. By delignifying by the alkaline oxygen bleaching method, the amount of bleaching chemical used in the subsequent multistage bleaching step can be reduced, and degradation of pulp quality can be minimized. As the alkaline oxygen bleaching method, a known medium concentration method or high concentration method can be applied as it is, but a medium concentration method in which the pulp concentration currently used for general purposes is 8 to 15% by mass is preferable.

In the alkali oxygen bleaching method by the medium concentration method, caustic soda or oxidized kraft white liquor can be used as the alkali. As the oxygen gas, oxygen from a cryogenic separation method, PSA (Pressure Swing Adsorption) Oxygen, oxygen from VSA (Vacuum Swing Adsorption), or the like can be used.
The oxygen gas and alkali are added to a medium-concentration pulp slurry in a medium-concentration mixer. After sufficient mixing, the oxygen gas and alkali are sent to a reaction tower capable of holding a mixture of pulp, oxygen, and alkali for a certain period of time under pressure. Ligned.

  The oxygen gas addition rate is 0.5 to 3% by mass per bone dry pulp mass, the alkali addition rate is 0.5 to 4% by mass, the reaction temperature is 80 to 120 ° C., the reaction time is 15 to 100 minutes, and the pulp concentration Is 8 to 15% by mass, and other known conditions can be applied. In the alkali oxygen bleaching step, the alkali oxygen bleaching is preferably performed twice or more continuously. The alkaline oxygen bleaching is preferably performed up to 3 times.

  The pulp that has been subjected to alkaline oxygen bleaching is then washed and then sent to a multi-stage bleaching process. In the multi-stage bleaching process, it is preferable to use an ozone bleaching stage (Z). By using the ozone bleaching stage, hexeneuronic acid contained in a large amount in pulp from acacia wood or eucalyptus wood can be decomposed, and the color return of the pulp due to hexeneuronic acid can be suppressed. The treatment conditions of the ozone bleaching stage are not particularly limited, but when ozone is excessively reacted, the pulp strength is impaired. Therefore, the ozone addition rate is preferably 0.1 per mass of the dry pulp. It is -1.0%, More preferably, it is 0.3-0.7%. The treatment temperature is 10 to 100 ° C., preferably 20 to 70 ° C., the treatment time is 1 second to 60 minutes, preferably 10 seconds to 5 minutes, and the treatment pH is 1.5 to 7, preferably 2 to 4. The pulp concentration in the ozone bleaching stage may be medium or high and is not limited. If desired, chlorine dioxide or other bleaching chemicals can be used in combination.

  The bleaching stage that can be used in the multistage bleaching process is not particularly limited, and a known bleaching stage can be used. Known bleaching stages include chlorine dioxide bleaching stage (D), alkali extraction stage (E), oxygen bleaching stage (O), hydrogen peroxide bleaching stage (P), peracid bleaching stage (PA), acid washing stage (a ) Or acid treatment stage (A). Examples of the multi-stage bleaching process include ZEPD, ZEDP, ZEPP, AZPEPD, and AZED. -P, A-Z-E-P-AP, a-Z-E-P-D, a-Z-E-D-P, a-Z-E-P-AP, Z / D-E-P -D, Z / D-E-D-P, Z / D-E-P-AP, A-ZD-E-P-D, A-Z / D-E-D-PA-Z / DE -P-AP, a-Z / D-E-P-D, a-Z / D-E-D-P, a-Z / D-E-P-AP, Z-EO-P-D, Z -EO-DP, Z-EO-P-AP, AZ-EO-PD, AZ-EO-DP, AZ-EO-P-AP, a-Z-EO -P-D, a-Z-EO-DP, a-Z-EO-P-AP, Z / D-EO-PD, Z / D-EO-DP, Z / D-EO -PA A-ZD-EO-PD, AZ / D-EO-DP, AZ / D-EO-P-AP, aZ / D-EO-PD, a-Z / D-EO-DP, a-Z / D-EO-P-AP, D-E-P-D, D-E-D-P, D-E-P-AP, A-D-E -P-D, A-D-E-D-P, A-D-E-P-AP, a-D-E-P-D, a-D-E-D-P, a-D-E -P-AP, D-EO-PD, D-EO-DP, D-EO-P-AP, AD-EO-PD, AD-EO-DP, A -D-EO-P-AP, a-D-EO-P-D, a-D-EO-DP, or a-D-EO-P-AP, and the like. It can also be provided. Further, a bleaching stage can be further added, or another bleaching stage can be incorporated in the bleaching stage and used together, and is not particularly limited.

(Paper making process)
The bleached pulp obtained by the bleaching process as described above is sent to the papermaking process through a known beating process if desired.
Here, the bleached pulp sent to the papermaking process preferably has a total content of linear alcohol (A) and linear fatty acid (B) of 300 ppm or more based on the total mass of the bleached pulp sent to the beating process. More preferably, it is 600 ppm or more, and more preferably 1,000 ppm or more. If it is such a bleached pulp, the uncoated paper whose total content of linear alcohol (A) and linear fatty acid (B) is 100-2000 ppm with respect to the mass of the whole paper or the whole base paper, and Easy to obtain coated paper. On the other hand, when bleached pulp having a total content of less than 300 ppm relative to the total mass of bleached pulp sent to the beating process is subjected to the papermaking process, the linear alcohol (A ) And the straight chain fatty acid (B) in the paper or base paper, the total content tends to be less than 100 ppm relative to the weight of the whole paper or the whole base paper.
The range of the total content of the linear alcohol (A) and the linear fatty acid (B) in the bleached pulp sent to the papermaking process is preferably 300 to 3500 ppm with respect to the mass of the whole paper or the whole base paper, 600 -3500 ppm is more preferable, and 1000-3500 ppm is more preferable.

As the papermaking method, an acid papermaking method or a neutral or alkaline papermaking method can be arbitrarily adopted. Can be used.
At this time, controlling the yield of fine fibers is important in adjusting the total content of linear alcohol (A) and linear fatty acid (B) in the base paper of the non-coated paper and coated paper. . That is, since the fine fiber has a high content of the straight chain alcohol (A) and the straight chain fatty acid (B), the yield of the fine fiber in the paper making process can be obtained directly from the obtained non-coated paper and the base paper of the coated paper. The total content of the chain alcohol (A) and the straight chain fatty acid (B) is affected.

  Specifically, the yield of fine fibers can be reduced by increasing the paper making speed, the mesh size of the wire mesh, or the foil angle, respectively, or by reducing the amount of the added yield agent or coagulant. The total content of the linear alcohol (A) and the linear fatty acid (B) in the base paper of the non-coated paper and coated paper obtained can be greatly reduced. Moreover, the yield of fine fibers can also be reduced by changing the ratio of white water (circulated reuse water including pulp fibers) / fresh water used for papermaking to increase the ratio of fresh water.

  In the paper making process in the method for producing the base paper of the non-coated paper and the coated paper of the present invention, at least one selected from the group consisting of calcium carbonate, colloidal silica, and calcined kaolin with respect to the paper stock to be made. As a result, the linear alcohol (A) and the linear fatty acid (B) are adsorbed on these, and as a result, the linear alcohol (A) on the surface of the non-coated paper measured by TOF-SIMS. ) And the linear fatty acid (B) can be reduced to 15 or less, more preferably 0.5 to 10.

Each addition amount and total addition amount of calcium carbonate, colloidal silica, and calcined kaolin is such that the total abundance of linear alcohol (A) and linear fatty acid (B) on the surface of the non-coated paper falls within the above range. However, the ash content measured by the ash content test method (525 ° C. combustion method) described in JIS P 8251: 2003 in the base paper of the uncoated paper or coated paper finally obtained is 35% by mass. It is preferable to add in the following range. If the addition exceeds 35% by mass, problems such as a decrease in paper strength due to these additions may occur, and inconveniences such as poor operability during papermaking may occur.
The range of the ash content is preferably 0.5 to 35% by mass, and more preferably 1 to 20% by mass.

  When adding calcium carbonate alone, adding so that the content of calcium carbonate in uncoated paper or base paper of coated paper is 3 to 20% by mass, and adding colloidal silica alone Is added so that the content of colloidal silica in the non-coated paper or the base paper of the coated paper is 0.01 to 2.0% by mass, preferably 0.1 to 2.0% by mass, When adding the calcined kaolin alone, it is preferable to add so that the content of the calcined kaolin in the non-coated paper or the base paper of the coated paper is 1 to 15% by mass. If the amount added is less than the lower limit, the total abundance of the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper may not be within the above range. On the other hand, when the upper limit is exceeded, problems such as reduction in paper strength due to the addition of these may occur, and inconveniences such as poor operability during papermaking may occur.

When two types of calcium carbonate and colloidal silica are added, the content of calcium carbonate in the non-coated paper or the base paper of the coated paper is based on the total mass of the non-coated paper or the base paper of the coated paper. It is preferably added so that the content of the colloidal silica is 0.01 to 2.0% by mass with respect to the mass of the whole base paper of the non-coated paper or the coated paper. .
When two types of colloidal silica and calcined kaolin are added, the content of colloidal silica in the non-coated paper or the base paper of the coated paper is based on the total mass of the non-coated paper or the base paper of the coated paper. 0.01 to 2.0% by mass, preferably added so that the content of calcined kaolin is 0.5 to 10.0% by mass with respect to the total mass of the uncoated paper or the base paper of the coated paper. .
When two types of calcium carbonate and calcined kaolin are added, the content of calcium carbonate in the non-coated paper or the base paper of the coated paper is based on the total mass of the non-coated paper or the base paper of the coated paper. 1.0 to 15.0% by mass, preferably added so that the content of calcined kaolin is 0.5 to 10.0% by mass with respect to the total mass of the uncoated paper or the base paper of the coated paper. .
When three types of calcium carbonate, colloidal silica, and calcined kaolin are added, the content of calcium carbonate in the non-coated paper or the base paper of the coated paper is the mass of the whole base paper of the non-coated paper or coated paper. 1.0 to 15.0% by mass with respect to the total mass of the colloidal silica with respect to the total mass of the uncoated paper or the base paper of the coated paper, and the content of calcined kaolin. Is preferably added so as to be 0.5 to 10.0% by mass relative to the mass of the whole base paper of non-coated paper or coated paper.

The total abundance of the linear alcohol (A) and the linear fatty acid (B) on the surface of the non-coated paper is thus selected from the group consisting of calcium carbonate, colloidal silica, and calcined kaolin in the stock. It can be adjusted by adding at least one substance.
As calcium carbonate, those having an average particle diameter of 1.0 to 10.0 μm by a laser diffraction scattering method are preferable. Either heavy calcium carbonate or light calcium carbonate can be used, but light calcium carbonate is preferred. The colloidal silica preferably has an average particle diameter of 1 to 200 nm by a dynamic light scattering method, more preferably 2 to 100 nm, still more preferably 2 to 50 nm, and particularly preferably 2 to 9 nm. The calcined kaolin preferably has an average particle size of 0.5 to 10.0 μm by a laser diffraction scattering method.

In the production of the non-coated paper and the base paper of the coated paper of the present invention, the paper stock is made of at least one substance selected from the group consisting of bleached pulp, calcium carbonate, colloidal silica, and calcined kaolin. Other commonly used fillers; internal sizing agents; anionic, nonionic, cationic or amphoteric retention improvers; drainage improvers; or paper additive aids such as paper strength enhancers Can be added.
Examples of the filler added in the production of the uncoated paper and the base paper of the coated paper of the present invention include calcium sulfite, gypsum, talc, kaolin, delaminated kaolin, hydrated silicate, diatomaceous earth, magnesium carbonate, Examples include inorganic pigments such as barium carbonate, zinc oxide, silicon oxide, titanium dioxide, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, or zinc hydroxide, and organic pigments such as urea / formalin resin fine particles or fine hollow particles. it can. Moreover, when used paper, waste paper, etc. are used as a pulp raw material, the filler contained in these can also be contained. Two or more fillers can be used in combination.

  Specific examples of the internally added sizing agent in the production of the non-coated paper and the base paper of the coated paper of the present invention include, for example, alkyl ketene dimer type, alkenyl ketene dimer type, alkenyl succinic anhydride type, styrene-acrylic type, high grade Examples include sizing agents such as fatty acid-based, petroleum resin-based, and rosin-based. Specific examples of yield improvers, drainage improvers, and paper strength enhancers include, for example, polyvalent metal compounds such as aluminum (specifically, sulfate bands, aluminum chloride, sodium aluminate, or bases). Examples thereof include various types of starch, polyacrylamide, urea resin, polyamide polyamine resin, polyethyleneimine, polyamide polyamine epichlorohydrin resin, polyvinyl alcohol, and polyethylene oxide.

  In addition, in the production of the non-coated paper and the base paper of the coated paper of the present invention, a bulking agent having a function of inhibiting the binding between pulp fibers and a softening agent are used as long as the desired effects of the present invention are not hindered. It is also possible. Specific examples of the bulking agent and the softener include, for example, an ester compound of a polyhydric alcohol and a fatty acid, a polyoxyalkylene compound of a polyhydric alcohol and a fatty acid ester compound, a fatty acid polyamidoamine, a polyhydric alcohol surfactant, or an oil and fat. Examples thereof include nonionic surfactants. Generally the addition amount of this bulking agent and a softening agent is about 0.05-2.0 mass% with respect to a pulp. These internally added chemicals are preferably added before a fan pump that requires a large share.

  In addition, the base material of the non-coated paper and coated paper of the present invention includes sodium chloride, potassium chloride, calcium chloride, sodium sulfate, zinc oxide, titanium dioxide, and tin oxide for the purpose of adjusting the electrical resistance value. Inorganic materials such as aluminum oxide or magnesium oxide, and organic materials such as alkyl phosphate ester salts, alkyl sulfate ester salts, sodium sulfonate salts, or quaternary ammonium salts may be used alone or in combination. it can. In consideration of environmental conservation, those not containing chlorine molecules are preferable.

  In addition, non-coated paper and coated paper of the present invention, non-coated paper and base paper made by using various paper machines, using a size press machine, such as synthetic adhesive such as polyacrylamide, starch, etc. By applying a surface treatment to the non-coated paper and base paper obtained above with a size press liquid containing a natural adhesive as a main component, the surface strength of the paper and the paper interlayer strength can be enhanced.

  Further, the non-coated paper and the coated paper base paper may be subjected to a smoothing finishing process using a soft calendar or the like.

  Examples of the size press device include a transfer type size press device such as a conventional general-purpose two-roll type size press device, a gate roll size press, or an application head metering size press such as a shim sizer.

In the production of the non-coated paper and the base paper of the coated paper of the present invention, the size press apparatus attached to the high-speed paper machine is used from the viewpoint of operability and excellent quality, such as an application head metering size press. A transfer type size press is preferred.
The coating amount of the size press solution is preferably about 0.5 to 13 g / m ² (in terms of solid content).

  In the production of the non-coated paper and the base paper of the coated paper of the present invention, when the high-speed paper machine and the transfer type size press device are operated on-machine specifications, the adhesive in the size press liquid supplied to the size press device The solid content concentration is usually 2 to 12% by mass, preferably 4 to 10% by mass. If the solid content concentration exceeds 12% by mass, the penetration of the size press liquid into the base paper is not sufficiently performed, and the effect of improving the interlaminar strength is small. However, the amount of the size press liquid that can be permeated is naturally limited, and as a result, the amount of adhesive in the paper layer becomes insufficient, and the effect of improving the strength between the paper layers cannot be expected. In addition, if the concentration of the size press solution is lowered more than necessary, the drying load of the base paper after the size press treatment increases, which is not a desirable embodiment in high-speed papermaking.

  The adhesive used in the size press process in the production of the uncoated paper and the base paper of the coated paper of the present invention includes starch purified from natural plants, hydroxyethylated starch, oxidized starch, etherified starch, phosphate ester Modified starch, enzyme-modified starch and cold water soluble starch obtained by flash drying them; or natural polysaccharides such as dextrin, mannan, chitosan, arabinogalactan, glycogen, inulin, pectin, hyaluronic acid, carboxymethylcellulose, or hydroxyethylcellulose And oligomers thereof, and modified products thereof. Furthermore, natural proteins such as casein, gelatin, soybean protein, or collagen and modified products thereof; or synthetic polymers and oligomers such as polylactic acid or peptides can be used. In addition, each (co) polymer latex such as styrene-butadiene, acrylic, polyvinyl acetate, or ethylene-vinyl acetate; or polyvinyl alcohol, modified polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, polyacrylamide, urea, or And water-soluble polymers such as melamine / formalin resin, polyethyleneimine, or polyamide polyamine epichlorohydrin resin. One or more of these can be used. In addition, the use of known natural or synthetic organic compounds is not particularly limited.

Moreover, you may add a pigment to the size press liquid of the base paper of uncoated paper and coated paper if desired. Examples of the pigment include pigments for ordinary coated paper such as kaolin, barium sulfate, light calcium carbonate, heavy calcium carbonate, aluminum hydroxide, satin white, titanium dioxide, calcium sulfite, zinc sulfate, or plastic pigment. Can be mentioned. Of these, use of heavy calcium carbonate is preferable because the air permeability of the base paper can be lowered and blister trouble can be suppressed when printed on an offset rotary printing press. When a pigment is blended in the size press liquid of the base paper of non-coated paper and coated paper, the blending ratio is preferably 5 to 200 parts by weight of the adhesive with respect to 100 parts by weight of the pigment, more preferably 10 to 100 parts by weight. preferable. Moreover, it is preferable that the coating amount of the size press liquid is about 0.5 to 13 g / m ² .
When calcium carbonate is used in the size press solution for the base paper of non-coated paper and coated paper, it is preferable to adjust the amount of calcium carbonate added, including the amount thereof, within the above range.

  Each component added to the non-coated paper exemplified above has an ash content of the obtained non-coated paper (according to the ash content test method (525 ° C. combustion method) described in JIS P 8251: 2003) of 35% by mass or less. It is preferable to add in the range. The ash content here includes the ash content originally contained in the pulp and the ash content contained in the old paper when used as a raw material. Therefore, each component is added in consideration of the amount of ash derived from these raw materials.

The basis weight of the non-coated paper is paper in these papermaking conditions, preferably ^{30~150g / m 2, 64~110g / m} 2 is more preferable. When the basis weight exceeds 150 g / m ² , the heat capacity becomes too large during heat fixing when used in a copying machine, so that the toner cannot be melted uniformly and unevenly, resulting in uneven melting. There is a possibility that uneven gloss or density in the density portion, fixing failure may occur, or the paper becomes too large, resulting in poor running. On the other hand, if it is less than 30 g / m ² , the toner is excessively melted at the time of fixing, so that uneven toner permeation cannot be avoided, the graininess is deteriorated, and the image gloss may become too high.

The base paper of the non-coated paper and the coated paper thus produced has a total content of linear alcohol (A) and linear fatty acid (B) of 100 to 2000 ppm, and non-coated paper. Since the total abundance of the linear alcohol (A) and the linear fatty acid (B) on the surface of the coated paper is controlled to 15 or less, the coefficient of static friction is controlled and the dimensional stability is good. In addition, the occurrence of running defects and wrinkles when used in copying machines and printers is reduced.
Moreover, the static friction coefficient (ISO15359: 1999) of the non-coated paper obtained in this way is in the range of 0.40 to 0.70. The static friction coefficient is preferably 0.50 to 0.65, and more preferably 0.55 to 0.61.

  The non-coated paper of the present invention has a freeness measured in accordance with JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998, JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method specified in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30 to 1.90. It is preferable that Such non-coated paper is suppressed from heat shrinkage wrinkles and the like. For example, a non-coated paper obtained using acacia wood as a pulp raw material tends to have a narrow fiber length distribution coefficient.

When the freeness of the disaggregated pulp of the non-coated paper of the present invention is less than 380 ml, curling is likely to occur on the non-coated paper due to environmental changes, and double feeding is likely to occur. Also, when the freeness exceeds 550 ml, the pulp fibers in the non-coated paper are not uniformly dispersed, the formation is poor, and the shrinkage unevenness at the time of heat fixing occurs, so wrinkles occur. It becomes easy.
When the weight-weighted average fiber length of the disaggregated pulp of the non-coated paper of the present invention is less than 0.6 mm, the bonding area between the fibers is small and the strength is insufficient. It becomes easy.
Conversely, when the weight-weighted average fiber length of the disaggregated pulp exceeds 0.9 mm, the texture becomes poor. Wrinkles are likely to occur in the paper.
When the fiber length distribution coefficient of the disaggregated pulp of the non-coated paper of the present invention is less than 1.30, there are few fibers with different fiber lengths that strengthen the paper interlayer bond, and the bond area between fibers becomes small, resulting in insufficient strength. The obtained non-coated paper is easily peeled from the paper.
In addition, when the fiber length distribution coefficient of the disaggregated pulp exceeds 1.60, the number of long fibers and fine fibers increases and the texture deteriorates. Therefore, when printing is performed with a non-impact printer of a type that heat fixes toner, Shrinkage stress tends to cause wrinkles on the uncoated paper.

Here, the fiber length distribution coefficient is a numerical value obtained by dividing the weight weighted average fiber length (W) by the number average fiber length (M), and is a value obtained by the following equation.
Fiber length distribution coefficient = weight-weighted average fiber length (W) / number average fiber length (M)
The larger the fiber length distribution coefficient, the wider the fiber length distribution, and the smaller the fiber length distribution coefficient, the narrower the fiber length distribution. The weight-weighted average fiber length and the number average fiber length are those of JAPAN TAPPI No. It is a value measured by an optical automatic measurement method defined in 52: 2000.

  The weight-weighted average fiber length, fiber length distribution coefficient, and freeness of the disaggregated pulp from the produced non-coated paper are the weight-weighted average fiber length, fiber length distribution coefficient of pulp used during papermaking, And the freeness does not necessarily match. This is because when making paper, some of the fine fibers come out of the wire mesh or net, and the aggregation state of the pulp fibers changes depending on the conditions in the wire part, press part, and dryer part (drying process), In the preparation process until it is sent to the wire part, the beating method, the dehydration method in the wire part and / or various internal additives are used to improve the strength between the paper layers or to improve the yield or formation. This is for adjusting the size and / or shape of flocs formed between pulp fibers.

  More preferable uncoated paper has a freeness of disaggregated pulp of 350 to 550 ml, a weight-weighted average fiber length of 0.60 to 0.80 mm, and a fiber length distribution coefficient of 1.30 to 1.60. .

  That is, another aspect of the present invention was obtained by adding a cooking solution to pulp raw material in a divided manner, bleaching unbleached pulp obtained by the cooking, and bleaching. A method for producing a non-coated paper, comprising making bleached pulp, and adding the cooking liquor to the pulp raw material for cooking and / or bleaching the unbleached pulp in the washing water Adjusting the amount of linear alcohol (A) and linear fatty acid (B) removed during washing by changing the ratio of filtered water and fresh water contained, and bleaching the unbleached pulp Including the delignification by the alkaline oxygen bleaching method and the multi-stage bleaching step, and the paper making is performed by selectively using the direct feed pulp or the pulp that has been once made for the paper stock to be made. When using pulp, change the ratio of filtered water and fresh water contained in the washing water in the valveless filter, change the paper making speed, change the yield agent amount, or white water that collects the water used as dilution water in the paper making process. According to JIS P 8251: 2003, the non-coated paper is obtained by changing at least one substance selected from the group consisting of calcium carbonate, colloidal silica, and calcined kaolin, by changing the ratio of fresh water that is industrial water. Including bleaching pulp obtained by bleaching, including addition in a range where ash content measured by an ash content test method (525 ° C. combustion method) is 35% by mass or less, and straight chain alcohol (A) and straight chain It is related with the said manufacturing method whose total content with a fatty acid (B) is 300 ppm with respect to the total mass of a bleached pulp.

The basis weight of the base paper of the coated paper of the present invention is not particularly limited, is preferably about 25 to 150 g / ^{m 2,} more preferably about 40 to 100 g / ^{m 2.}

The base paper of the coated paper of the present invention made as described above is JAPAN TAPPI Paper Pulp Test Method No. 5-2: The air permeability measured according to 2000 is 10 seconds or less. JAPAN TAPPI Paper Pulp Test Method No. It is preferable that the internal bond strength measured according to 18-2: 2000 is 150 to 800 J / m ² . A more preferable air permeability is 8 seconds or less. Further, a more preferable internal bond strength is 300 to 600 J / m ² .
If the air permeability exceeds 10 seconds, it is difficult for water vapor in the paper layer to escape during the ink drying process during off-ring printing, and blisters may be generated on the coated paper. On the other hand, if the internal bond strength is less than 150 J / m ² , the hydrogen bond between the pulp fibers is excessively inhibited, and there is a possibility that the paper strength that can withstand the off-wheel printing cannot be secured. If the internal bond strength exceeds 800 J / m ² , the effect of suppressing the occurrence of off-ring wrinkles is saturated, and the economy may be poor.

  In the coated paper of this invention, it is preferable that the fiber orientation ratio measured based on the ultrasonic propagation velocity measuring device of a base paper is 1.20 or less. Incidentally, when the fiber orientation ratio exceeds 1.20, it is insufficient to randomize the direction of the fibers constituting the base paper of the coated paper, and the effect of suppressing the lateral propagation of the drying shrinkage force during off-ring printing is effective. Become scarce.

  Here, the fiber orientation of the base paper refers to a tendency that the pulp fibers flow out onto the wire of the paper machine and are aligned in the outflow (longitudinal) direction in the process of dewatering and forming a paper layer. In other words, since the paper stock flows out on the wire and dehydrates at the time of paper making, the number of fibers oriented in the machine direction (the flow direction of the raw material on the paper machine) increases, and the tensile strength and rigidity in the machine direction are transverse. It is considerably stronger or higher than the direction (width direction). Probably, the difference between the vertical and horizontal directions (non-uniformity) of the base paper becomes the drying shrinkage distortion of the pulp fiber at the time of off-wheel printing, which is considered to be a cause of wrinkles.

In general, as a method for measuring the fiber orientation of paper or the like, for example, an ultrasonic method, a thermal expansion method, a mechanical breaking strength method, an X-ray diffraction method, a microwave method, an NMR method, a polarized fluorescence method, or a dielectric measurement method is used. Can be mentioned. In the present invention, the ultrasonic propagation velocity (V _md ) and the transverse ultrasonic propagation velocity (V _cd ) are measured by an ultrasonic method using, for example, “SONIC SHEEET TESTER” manufactured by Nomura Corporation. The ratio (V _md / V _cd ) is used as the fiber orientation ratio to evaluate the fiber orientation randomness. When the fiber orientation ratio is 1.0, the fiber orientation is completely random, but the actual machine paper has some fiber orientation.

On the other hand, since the fiber orientation ratio is determined by the papermaking conditions in the machine, it is necessary to make the operation on the machine appropriate. Possible means include optimization of machine speed, ratio of fiber suspension jet inflow speed to wire speed (J / W ratio), wire shake, homing board and weir board arrangement, or dandy roll. In particular, when making paper while sliding the wire horizontally and perpendicularly to the flow direction using a wire shaking device that can freely change the frequency and amplitude in the wire part, the direction of the pulp fibers is randomly oriented. Therefore, it is preferable. Furthermore, in machine operation, the speed of the rear part is generally faster, and paper is made while pulling the paper toward the reel. When this speed difference is increased, the pulp fibers are oriented in the flow direction. Therefore, in the production of the coated paper of the present invention, the ratio V between the reel rotation speed (V _r ) and the wire rotation speed (V _w ). _r / _{V w} is preferably from 1.01 to 1.07. It is possible to make the fiber orientation ratio 1.20 or less by combining one or more of these means, but it is necessary to achieve harmony with other physical properties such as paper texture.

(Manufacture of coated paper)
The method for forming a coating layer of the coated paper of the present invention comprises applying at least one coating layer comprising a pigment and an adhesive as a main component on at least one side of the base paper, and drying to form at least one coating layer. It is a method which has the process of forming, and the process of giving a pressure finishing process to a base paper and a coating layer.

  In the present invention, the pigment that can be used when a coating layer is provided on the base paper is not particularly limited, for example, various natural kaolin, talc, or purified natural mineral pigments such as heavy calcium carbonate, light carbonate Composite synthetic pigments of calcium or calcium carbonate and other hydrophilic organic compounds, satin white, lithopone, titanium dioxide, silica, alumina, aluminum hydroxide, zinc oxide, magnesium carbonate, calcined kaolin, hollow organic pigment, dense organic Examples include, but are not limited to, pigments, plastic pigments, binder pigments, plastic beads, or microcapsules.

  In the present invention, as an adhesive used in the coating layer, starch purified from natural plants, hydroxyethylated starch, oxidized starch, etherified starch, phosphate esterified starch, enzyme-modified starch and flash-dried them. Examples include cold water-soluble starch obtained; or natural polysaccharides such as dextrin, mannan, chitosan, arabinogalactan, glycogen, inulin, pectin, hyaluronic acid, carboxymethylcellulose, hydroxyethylcellulose, oligomers thereof, and modified products thereof. Further examples include natural proteins such as casein, gelatin, soybean protein, and collagen, and modified products thereof, or synthetic polymers and oligomers such as polylactic acid or peptides. In addition, each (co) polymer latex such as styrene-butadiene, acrylic, polyvinyl acetate, or ethylene-vinyl acetate, or polyvinyl alcohol, modified polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, polyacrylamide, urea, or And water-soluble polymers such as melamine / formalin resin, polyethyleneimine, or polyamide polyamine epichlorohydrin resin. One or more of these can be used. In addition, the use of known natural and synthetic organic compounds is not particularly limited.

  Further, in the formation of the coating layer of the coated paper of the present invention, as a thickener used in the coating solution, carboxymethyl cellulose, sodium alginate, methyl cellulose, hydroxymethyl cellulose, casein, sodium polyacrylate, or styrene-anhydrous Examples thereof include water-soluble polymers such as maleic acid copolymers, and inorganic polymers such as silicates.

  Furthermore, if necessary, various commonly used auxiliaries such as a dispersant, an antifoaming agent, a water-proofing agent, or a colorant, and those obtained by cationizing these various auxiliaries are suitably used.

  In the present invention, the method for applying the coating liquid is not particularly limited, and various blade coaters such as trailing, flexible, roll application, fountain application, or short dwell; size press, gate roll, or Various transfer coaters such as Simsizer; or each method such as air knife coater, bar coater, rod coater, rod blade coater, Champlex coater, gravure coater, curtain coater, die coater, direct fountain coater, spray coater or cast coater It can be used as appropriate. These devices may be on-machine or off-machine.

The coating amount of the coating layer is not particularly limited. For example, in the case of two-layer coating, both the undercoat coating layer and the topcoat coating layer have a dry mass of about 1.5 to 15 g / m ² per side and can be obtained. In consideration of the white paper quality, print quality and printability of the coated paper, as well as the drying capacity at the time of producing the coated paper, about 5 to 30 g / m ² per side including the undercoat coating layer and the top coating layer. It is desirable to be in the range. As a method for drying the wet coating layer, for example, various methods such as steam drying, gas heater drying, electric heater drying, and infrared heater drying can be adopted.

In the coated paper of the present invention, a third coating layer that is in contact with the undercoat layer may be formed between the base paper and the three or more layers. The composition and the coating amount of the third coating layer are not particularly limited, and a coating liquid containing an arbitrary pigment and / or adhesive as a main component is 0.5 to 10 g per side in terms of dry mass. / M ² may be applied with a transfer type size press device or the like and dried.
In the coated paper of the present invention, it is preferable to provide 1-4 coating layers per side, more preferably 1-3 layers, and even more preferably 1-2 layers.

  In the production of the coated paper of the present invention, after the formation of the coating layer, a smoothing process is performed by various calendar devices. Examples of such a calendar device include a super calender, a soft calender, and a gloss calender. Commonly used calendar devices such as a render, a compact calendar, a mat super calendar, or a mat calendar can be used as appropriate. As the calender finishing conditions, the temperature of the rigid roll, the calender pressure, the number of nips, the roll speed, the paper moisture before the calender, and the like are appropriately selected according to the required quality. Furthermore, the calendar device includes an off-type that is different from the coater and an on-type that is integrated with the coater, both of which can be used. The material of the calendar device to be used is a roll which is mirror-finished with a metal or a hard chrome plating on the surface of the rigid roll. As the elastic roll, a resin roll such as urethane resin, epoxy resin, polyamide resin, phenol resin, or polyacrylate resin, or a roll formed from cotton, nylon, asbestos, aramid fiber, or the like is appropriately used. It is also possible to use an appropriate combination of a water coating device, an electrostatic humidifying device, a steam humidifying device, or the like for conditioning or humidifying the coated paper after finishing with a calendar.

The basis weight of the thus coated paper that is manufactured is not particularly limited, but is preferably ^{30~150g / m 2, 64~110g / m} 2 is more preferable.

  In the coated paper of the present invention, since the total content of the linear alcohol (A) and the linear fatty acid (B) in the base paper is controlled to 100 to 2000 ppm with respect to the mass of the base paper, the dimensional stability Therefore, curling is suppressed, drying shrinkage is suppressed during heat drying in offset rotary printing, and generation of off-roll wrinkles is reduced.

  In the coated paper of the present invention, the freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 380 to 550 ml, JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method specified in 52: 2000 is 0.60 to 0.90 mm, and the fiber length distribution coefficient is 1.30 to 1.90. It is preferable that Such coated paper is suppressed from heat shrinkage and wrinkles. For example, a paper obtained using acacia wood as a pulp raw material tends to have such a narrow fiber length distribution coefficient.

When the freeness of the disaggregated pulp of the coated paper of the present invention is less than 380 ml, curling is likely to occur due to environmental changes, dimensional stability is deteriorated, and off-wrinkles are likely to occur. On the other hand, if the freeness exceeds 550 ml, the pulp fibers in the paper are not uniformly dispersed, the formation is poor, and the paper is easily peeled.
When the weight-weighted average fiber length of the disaggregated pulp of the coated paper of the present invention is less than 0.60 mm, the interfiber bonding area is small and the strength is insufficient, so that the paper is easily delaminated.
Conversely, if the weight-weighted average fiber length of the disaggregated pulp exceeds 0.90 mm, the interfiber bonding area increases, the dimensional stability deteriorates, and off-roll wrinkles are likely to occur.
When the fiber length distribution coefficient of the disaggregated pulp of the coated paper of the present invention is less than 1.30, there are few fibers of different fiber lengths that strengthen the paper interlayer bond, and the bond area between fibers becomes small and the strength becomes insufficient. Paper delamination becomes easy.
On the other hand, when the fiber length distribution coefficient of the disaggregated pulp exceeds 1.90, the number of long fibers and fine fibers increases, the interfiber bonding area increases, the dimensional stability deteriorates, and off-roll wrinkles tend to occur.

  Here, the fiber length distribution coefficient is synonymous with the fiber length distribution coefficient of the non-coated paper described above.

  The weight-weighted average fiber length, fiber length distribution coefficient, and freeness of the disaggregated pulp from the manufactured coated paper are the weight-weighted average fiber length, fiber length distribution coefficient, and pulp used in papermaking. It does not necessarily match the freeness. This is because part of the fine fibers come off from the wire mesh or net when making paper, and the aggregation state of pulp fibers changes depending on the conditions in the wire part, press part, or dryer part (drying process), In the preparation process until it is sent to the wire part, in order to improve the strength between the paper layers, or to improve the yield and formation, the beating method, the dehydration method in the wire part and / or various internal chemicals This is for adjusting the size and / or shape of flocs formed between pulp fibers.

  In the coated paper of the present invention, the freeness of the disaggregated pulp is more preferably 400 to 500 ml, the weight-weighted average fiber length is 0.60 to 0.80 mm, and the fiber length distribution coefficient is 1.30 to 1.60. It is.

  The coated paper of the present invention uses, as printing conditions, an offset sheet-fed printing machine (SM102, manufactured by Heidelberg), and is printed in four colors (printing order: black, indigo, red, yellow) (ink: Fusion G EZ N type) , Manufactured by DIC Corporation), printed at a printing speed of 12000 copies / hour, and after 10 hours, a stack of 10 chrysanthemum size (636 mm x 939 mm) was suspended from the top, resulting in MD curl of less than 30 mm, resulting in curling Can be suppressed. In addition, since the equilibrium moisture of the paper is low, curling due to environmental changes is less likely to occur.

  That is, another aspect of the present invention is that the cooking liquid is dividedly added to the pulp raw material and cooked, the unbleached pulp obtained by the cooking is bleached, and the bleaching obtained by the bleaching. A method for producing a coated paper, comprising forming a pulp, and forming a coating layer on the base paper obtained in the paper making, wherein the pulp raw material is divided and added to digest the cooking liquid And / or bleaching the unbleached pulp by changing the ratio of filtered water and fresh water contained in the washing water, thereby removing the linear alcohol (A) and the linear fatty acid (B) removed during washing Adjusting the amount, bleaching the unbleached pulp includes delignification by an alkaline oxygen bleaching method and a multi-stage bleaching step, and the papermaking includes the direct pulp or once Select and use the finished pulp, and when using direct feed pulp, change the ratio of filtered water and fresh water contained in the wash water in the valveless filter, change the speed, change the yield, or dilute in the paper making process. Changing the ratio of white water recovered from water used as water and fresh water as industrial water, and forming the coating layer is a coating mainly comprising a pigment and an adhesive on at least one side of the base paper. It is obtained by bleaching, which includes forming a coating liquid and drying to form at least one coating layer, and subjecting the base paper and the coating layer to a pressure finishing treatment. The total content of the straight-chain alcohol (A) and the straight-chain fatty acid (B) of the bleached pulp is 300 ppm relative to the mass of the entire bleached pulp.

  The present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples. The part and% in an Example show a mass part and the mass%.

(Production of calcium carbonate slurry (A))
A calcium carbonate slurry (A) was produced by the method described in JP-A-5-163018 “Method for producing calcium carbonate”. The reaction tank was charged with 600 liters of 9.0 mass% aqueous calcium hydroxide suspension, and the dilution gas (carbon dioxide concentration: 20% by volume) was diluted with air and the flow rate was 1500 liters / minute ( (15 ° C.).
As a means for forming fine bubbles of carbon dioxide, fine bubbles were bubbled from small holes (round shape, diameter 20 mm, opening rate 5%) formed in a conical gas reservoir (vertical angle 90 °) at the bottom of the reaction tank.
The reaction start temperature was 42 ° C., and the reaction time was 80 minutes. According to the average particle diameter of the obtained calcium carbonate (laser diffraction scattering method (the particle diameter at a point corresponding to a cumulative mass of 50% was defined as the average particle diameter). Apparatus: “Microtrack HRA” manufactured by Nikkiso Co., Ltd.) The molar extinction coefficient and apparent specific gravity were 6.2 μm, 17.9, and 0.25, respectively. This calcium carbonate is light calcium carbonate.

(Production of DIP (A))
Waste paper raw materials, mixed with the same amount of waste newspaper and magazine waste paper, were loaded into a high-concentration pulper and disintegrated.
The raw material after disaggregation was diluted to 1%, and as a dust removal process, it was sequentially processed with a screen having a hole basket and a slit basket. Furthermore, after processing in a deinking process using a floatator (trade name: OK Floatator, manufactured by Oji Engineering Co., Ltd.) and a cleaning process using an extractor, and then concentrating to 25% using a valveless thickener and a concentration process using a screw press. Add 3% hydrogen peroxide, 2% caustic soda and 2% sodium silicate, raise the temperature to 70 ° C, and use a disperser (manufactured by Aikawa Tekko Co., Ltd.) as a shaft type disperser for the first time. Went. The treated pulp was bleached for 3 hours while maintaining the temperature, and then a second dispersion treatment was performed using a disperser (manufactured by Aikawa Tekko Co., Ltd.) as a shaft type disperser.

The pulp after dispersion treatment is diluted to 1%, and further processed in a deinking process using a floatator (trade name: OK Flotator, manufactured by Oji Engineering Co., Ltd.), a washing process using an extractor, and a dust removing process using a slit basket screen. In a concentration step using a valveless thickener and screw press, the solution was concentrated to 35%. Add 1% thiourea dioxide (FAS) and 0.5% caustic soda to the concentrated pulp, raise the temperature to 110 ° C, and use the hot disperser (manufactured by KRIMA) as the disk type disperser for the third time. Was distributed. Further, it was concentrated to 10% by a washing process using an extractor and a concentration process using a valveless thickener to obtain a used paper pulp raw material (DIP) having a whiteness of 81%, CSF of 270 ml, and impurities of 110 pieces / m ² .

<Example 1>
(Manufacture of unbleached pulp (digestion process))
Using a Lo-solids digester (manufactured by Andritz), kraft cooking of hardwood chips consisting of Acacia Auricariformis: Eucalyptus maldrensis: Eucalyptus globulas = 40:40:20 (mass ratio) by Lo-solids cooking method did. Here, using white liquor having a sulfidity of 28 (distilled liquor), the white liquor addition rate is 10% per chip dry mass with respect to the chip supply system, 8% in the cooking zone and 8% in the washing zone, as the active alkali. 2% portion was added and the cooking temperature was 146 ° C. After the digestion of the chips after cooking, the washing process (filtered water / fresh water (100/0)), the screen process, and the washing process (filtered water / fresh water (100/0)) again, Bleached pulp) was obtained.

(Bleaching process)
To the unbleached pulp, 1.7% of caustic soda and 1.8% of oxygen per mass of dry pulp were added, and two-stage alkaline oxygen bleaching was performed under the conditions of a pulp concentration of 10%, 98 ° C. for 50 minutes.
Here, caustic soda was added all at once in the first stage, and oxygen gas was added in 1.0% in the first stage and 0.8% in the second stage. The pulp after alkaline oxygen bleaching was washed in the washing step.

After 1.2% sulfuric acid was added to the pulp after the alkali oxygen bleaching, and the pulp was retained under the conditions of 10% pulp concentration, 60 ° C. and 60 minutes, it was washed in the washing step.
Next, 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp were added, and after intermediate concentration ozone / chlorine dioxide bleaching was performed at a pulp concentration of 10%, 58 ° C. for 60 minutes, washing was performed. It was washed in the process. Next, 1.0% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp are added, and after alkali extraction under conditions of pulp concentration 10%, 60 ° C, 90 minutes, washing treatment is performed in the washing step. did. Subsequently, 0.2% of chlorine dioxide was added per mass of dry pulp, and chlorine dioxide was bleached under conditions of 10% pulp density, 70 ° C. and 120 minutes, and then washed in the washing step to obtain bleached pulp. The ISO whiteness of the obtained bleached pulp was 90.1%. Subsequently, it was washed with filtered water / fresh water (100/0) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 566 ppm.

(Beating process)
Double disk refiner (blade material) in which bleached pulp (concentration: 4.2% by mass) washed with filtered water / fresh water (100/0) is connected in parallel with three machines (the same blade is used) : Ni-Hard, blade width: 4.0 mm, groove width: 4.0 mm) and beaten to 440 ml of CSF to obtain a beaten pulp slurry.

(Paper making process)
To the beaten pulp slurry, 0.04% alkenyl succinic anhydride sizing agent (Fibrane 81K / Arakawa Chemical Industries), 0.5% aluminum sulfate (vs. pulp, solid content conversion), cationized starch (product) Name: Oji Ace K (manufactured by Oji Cornstarch Co., Ltd.) 1.1% (vs. pulp, solid content conversion) was sequentially added to the machine chest. (A) was added before the fan pump so that the content in the non-coated paper obtained was 3.5%. Furthermore, 0.016% of a cationic acrylic resin (trade name: DR-3015, manufactured by Hymo Co., Ltd.) was added as a retention agent in front of the screen to prepare a paper stock (concentration: 1.01%).
This paper stock was formed with an on-top former at a J / W ratio of 0.995 and a papermaking speed of 1,010 m / min, squeezed with three roll presses, dried with a single-stage dryer, and then on-machine Surface sizing was performed with a specified two-roll size press. That is, a size press solution consisting of 2% oxidized starch, styrene-methacrylic acid copolymer-based surface sizing agent (Polymaron NP-25 / Arakawa Chemical Co., Ltd.) 0.10%, and sodium sulfate 0.3% in solid content 1 The uncoated paper having a moisture content of 4.5% and a basis weight of 64 g / m ² was obtained by applying the mixture so as to be 0.0 g / m ² and calendering. At the time of papermaking, the collected white water was not discharged. That is, in the paper making process, white water / fresh water (100/0) was used for paper making.

<Example 2>
As a hardwood chip, a chip comprising acacia mangum: eucalyptus maldrensis = 50: 50 is used, and the content of calcium carbonate slurry (A) in the non-coated paper is 5.3%. An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except for the amount. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm.

<Example 3>
Use hardwood chips: Acacia mangum: Acacia hybrid: Eucalyptus grounds = 60:30:10 Chips, beating up to 410ml CSF, addition amount of calcium carbonate slurry (A) uncoated paper The basis weight is 64 g / m ^{2 in} the same manner as in Example 1 except that the content is 7.5% and the addition amount of the cationic acrylic resin is 0.021%. Coated paper was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Example 4>
As a hardwood chip, a chip made of acacia mangum: eucalyptus maldrensis: eucalyptus globula = 80:10:10 was used. (50/50), beating up to 430 ml of CSF, and adding calcium carbonate slurry (A) before the fan pump so that the content in non-coated paper is 7.5%, and colloidal Silica (trade name: NP882, manufactured by Eka Chemicals, average particle size (according to dynamic light scattering method, device: manufactured by Nikkiso Co., Ltd., particle size / zeta potential measuring device “Nanotrack UPA-UZ152”): 3 nm) is not applied The addition to the machine chest so that the content in the paper is 0.05%, the addition amount of the cationic acrylic resin is 0.028. And the point, except that the machine speed and 925M / min, thereby obtaining the non-coated paper having a basis weight of 64 g / m ² in the same manner as in Example 1. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm.

<Example 5>
A hardwood chip consisting of acacia mangum: eucalyptus maldrensis = 80: 20 was used, and 2.5% of caustic soda per mass of dry pulp and 1.8% of oxygen were added to unbleached pulp. Next, two-stage alkaline oxygen bleaching was performed under the conditions of a pulp concentration of 10%, 98 ° C., and 50 minutes. The pulp after alkaline oxygen bleaching was added with 1.2% sulfuric acid per mass of dry pulp, and was retained under conditions of 10% pulp concentration, 60 ° C. for 60 minutes, and then washed in the washing step. Next, after adding 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp, medium concentration ozone / chlorine dioxide bleaching was performed at a pulp concentration of 10%, 58 ° C. for 60 minutes, followed by washing. It was washed in the process. Next, 1.4% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp were added, followed by alkali extraction under conditions of pulp concentration 10%, 60 ° C, 90 minutes, followed by washing treatment in the washing step. did. Calcium carbonate slurry (A) as a filler is added before the fan pump so that the content in non-coated paper is 7.0%, and colloidal silica (trade name: NP882, manufactured by Eka Chemicals) is not coated. An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the content in the paper was 0.20%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 3200 ppm.

<Example 6>
Use hardwood chips made of acacia mangum, beat with a double disc refiner to 370 ml CSF, and add a calcium carbonate slurry (A) as a filler so that the content in non-coated paper is 14.0% A basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that 0.021% of a cationic acrylic resin (trade name: DR-3015, manufactured by Hymo Co., Ltd.) was added in front of the screen. An uncoated paper was obtained. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating step was 2900 ppm.

<Example 7>
As a hardwood chip, a chip made of acacia mangum is used, and without adding calcium carbonate, colloidal silica (trade name: NP882, manufactured by Eka Chemicals Co., Ltd.) has a non-coated paper content of 0.30%. The basis weight in the same manner as in Example 1 except that the machine chest was added to the machine chest, the addition amount of the cationic acrylic resin was 0.021%, and the paper making speed was 915 m / min. An uncoated paper of 64 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2700 ppm.

<Example 8>
Non-coated colloidal silica (trade name: NP882, manufactured by Eka Chemicals Co., Ltd.) without adding calcium carbonate, using a chip made of acacia mangum: Eucalyptus maldrensis = 50: 50 as a hardwood chip An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the content in the paper was 0.08%. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm.

<Example 9>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis = 50: 50 was used. Example 1 except that it was added before the pump and colloidal silica (trade name: NP882, manufactured by Eka Chemicals Co., Ltd.) was added to the machine chest so that the content in the non-coated paper was 0.08%. Similarly, an uncoated paper having a basis weight of 64 g / m ² was obtained. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm.

<Example 10>
A cooking process similar to that of Example 1 was performed except that a hardwood chip made of acacia mangeum was used.
Subsequently, the bleaching process was performed like Example 1 and the bleached pulp was obtained. The ISO whiteness of the obtained bleached pulp was 90.1%. Subsequently, a pulp with a solid content of 50% was obtained. Subsequently, it was dispersed with a pulper and washed with filtered water / fresh water (50/50) in a valveless filter. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm. Beating was performed up to 450 ml of CSF.
Thereafter, a papermaking process was performed in the same manner as in Example 1 to obtain a non-coated paper having a moisture content of 4.5% and a basis weight of 64 g / m ² .

<Example 11>
As a hardwood chip, a chip composed of acacia mangum: acacia hybrid: eucalyptus globulus = 60: 30: 10, and the amount of calcium carbonate slurry (A) added was 7 in the non-coated paper. An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the amount was 0.5%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2000 ppm.

<Example 12>
A hardwood chip: acacia mangum: acacia hybrid: eucalyptus maldrensis: eucalyptus globula = 60: 30: 5: 5, and the amount of calcium carbonate (A) added in non-coated paper An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the content of A was 7.5%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2000 ppm.

<Example 13>
As a hardwood chip, a chip composed of acacia mangum: Eucalyptus maldrensis = 30: 70 was used, and the washing water used in the valveless filter in the previous stage of the bleaching pulp beating process was filtered water / fresh water (50/50). The point where the beating was performed up to 415 ml of CSF, the addition amount of the calcium carbonate slurry (A) was the amount that the content in the non-coated paper was 5.0%, the addition amount of the cationic acrylic resin A non-coated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that 0.024% was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 650 ppm.

<Example 14>
As a hardwood chip, a chip made of acacia aurikariformis: eucalyptus maldrensis = 85: 15 was used, and the amount of calcium carbonate slurry (A) added was 8.5% in the non-coated paper. An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the amount was adjusted and white water / clear water (85/15) was used for paper making in the paper making process. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1280 ppm.

<Example 15>
A hardwood chip made of acacia aurikariformis is used as a hardwood chip, 100 parts by weight of DIP (A) is mixed with 100 parts by weight of pulp obtained from the hardwood in the blending box at the front stage of the machine chest, and up to 410 ml of CSF is beaten. What was done, 5.5% calcium carbonate slurry (A) was added before the fan pump, and combined with the ash content (filler; calcium carbonate included) contained in DIP (A), resulting in uncoated paper Example 1 except that the ash content was 8.2% before the fan pump was added, the addition amount of the cationic acrylic resin was 0.024%, and the papermaking speed was 915 m / min. In the same manner as above, an uncoated paper having a basis weight of 64 g / m ² was obtained. It was 1300 ppm when the total content of the straight chain alcohol (A) and the straight chain fatty acid (B) in the mixed pulp was measured by sampling from a blending box in which pulp obtained from hardwood chips and DIP (A) were mixed. .

<Example 16>
A chip made of acacia mangum: acacia hybrid: eucalyptus grandis = 60:30:10 as a hardwood chip, a point where beating was performed up to 355 ml of CSF, and an added amount of calcium carbonate slurry (A) were uncoated paper The basis weight is 64 g / m ^{2 in} the same manner as in Example 1 except that the content is 7.5% and the addition amount of the cationic acrylic resin is 0.021%. An uncoated paper was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Example 17>
A hardwood chip: Acacia mangum: Acacia hybrid: Eucalyptus grounds = 60:30:10 Chip, beating up to 587 ml of CSF, addition amount of calcium carbonate slurry (A) uncoated paper The basis weight is 64 g / m ^{2 in} the same manner as in Example 1 except that the content is 7.5% and the addition amount of the cationic acrylic resin is 0.021%. An uncoated paper was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Example 18>
A hardwood chip: Acacia mangum: Acacia hybrid: Eucalyptus grounds = 60:30:10 Chip used, beating up to 405 ml CSF, calcium carbonate slurry (A) added amount of uncoated paper The basis weight is 64 g / m ^{2 in} the same manner as in Example 1 except that the content is 19.0% and the addition amount of the cationic acrylic resin is 0.021%. An uncoated paper was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Example 19>
In the same manner as in Example 2, except that calcined kaolin (trade name: Ansilex, manufactured by EMC) was added in place of calcium carbonate so that the content in non-coated paper was 5.3%. An uncoated paper having an amount of 64 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Comparative Example 1>
As the hardwood chip, a chip made of acacia aurikariformis: eucalyptus maldolensis = 10: 90 was used, and the amount of calcium carbonate slurry (A) added was 4.0% in the non-coated paper. An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the amount was determined as follows. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 240 ppm.

<Comparative example 2>
A chip made of acacia mangum was used as the hardwood chip, and the cooking process to the papermaking process were performed in the same manner as in Example 1.
However, in the bleaching step, the amount of caustic soda per mass of dry pulp added to unbleached pulp was 1.9%, and the amount of caustic soda per mass of dry pulp in alkali extraction was 1.5%. This point was changed from Example 1. The ISO whiteness of the obtained bleached pulp was 90.1%. Further, it was made into a pulp with a solid content of 50%, then dispersed with a pulper, and washed with filtered water / fresh water (100/0) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 4200 ppm.
In the beating process, beating was performed up to 450 ml of CSF.
In the paper making process, the amount of calcium carbonate slurry (A) added is changed to an amount that causes the content in the non-coated paper to be 7.0%, and colloidal silica (trade name: NP882, manufactured by Eka Chemicals) is not applied. It was added to the machine chest so that the content in the paper was 0.20%. Moreover, the addition amount of the cationic acrylic resin was changed to 0.022%. The stock concentration was 1.09%.
Then, a paper layer was formed in the same manner as in Example 1 except that the paper making speed was changed to 900 m / min. An uncoated paper having a basis weight of 64 g / m ² was obtained.

<Comparative Example 3>
A chip composed of acacia mangum: acacia hybrid: eucalyptus grandis = 60: 30: 10 was used as the hardwood chip, and the cooking process and the papermaking process were performed in the same manner as in Example 1. However, the point that the amount of caustic soda per mass of completely dried pulp added to the unbleached pulp was 1.9% and the addition amount of the calcium carbonate slurry (A) in the uncoated paper was 4. The point that the amount was 0% was changed from Example 1. An uncoated paper having a basis weight of 64 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2000 ppm.

<Comparative example 4>
A hardwood chip composed of acacia mangum: eucalyptus maldrensis = 50: 50 was used as the hardwood chip, and the cooking process and the papermaking process were performed in the same manner as in Example 1. However, the amount of caustic soda per mass of absolutely dry pulp added to unbleached pulp is 2.0%, and the wash water in the valveless filter when washing bleached pulp is filtered water / fresh water ( 50/50), the amount of the cationic acrylic resin added is 0.009%, and the amount of the calcium carbonate slurry (A) is 7.0% in the non-coated paper. And the point which used white water / shimizu (85/15) for papermaking in the papermaking process was changed from Example 1. An uncoated paper having a basis weight of 64 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 900 ppm.

<Comparative Example 5>
As a hardwood chip, a chip made of acacia aurikariformis: eucalyptus maldrensis: eucalyptus grandis = 10: 70: 20, a point of beating up to CSF 455 ml, and a non-addition amount of calcium carbonate slurry (A) An uncoated paper having a basis weight of 64 g / m ² was obtained in the same manner as in Example 1 except that the content in the coated paper was 7.0%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 240 ppm.

<Comparative Example 6>
Example except that talc (trade name: talc 80, manufactured by Fuji Talc Kogyo Co., Ltd.) was added in place of calcium carbonate slurry (A) so that the content in non-coated paper was 7.5%. In the same manner as in Example 3, an uncoated paper having a basis weight of 64 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating step was 1600 ppm.

<Comparative Example 7>
As the comparative example 7, the example according to the Example of patent document 1 was implemented.
Use 40% eucalyptus, 20% oak, and 40% acacia as wood chips, and add cooking white liquor so that the liquid ratio is 4, the sulfidity is 28%, and the effective alkali is 17% (as Na ₂ O) in the autoclave. Then, kraft cooking was performed at a cooking temperature of 160 ° C. The black liquor was separated after kraft cooking. The obtained chip was defibrated by a high-concentration disaggregator, and then centrifugal dehydration and water washing were repeated three times with a filter cloth. Next, the uncooked material is removed with a screen, centrifuged and dehydrated, kappa number 19.7, and the total amount of fatty acid and aliphatic alcohol in the dichloromethane extract is 0.16% by mass with respect to the total pulp mass. Pulp was obtained.

  To the pulp obtained by kraft cooking, 1.0% of NaOH is added, and 1% of an anionic surfactant (trade name: Gran Up CS-90, manufactured by Sanyo Chemical Co., Ltd.) is added. After the replacement water was added and the pulp concentration was adjusted to 10%, the surfactant was treated in a stirring autoclave at 90 ° C. for 90 minutes.

Next, after washing with ion-exchanged water and dehydration, unbleached pulp is obtained. To the pulp, 2.0% of NaOH is added, oxygen gas is injected, and treatment is performed at 100 ° C. and oxygen pressure of 5 kg / cm ² for 60 minutes. Went. The kappa number of the oxygen delignified pulp after washing and dehydration was 9.7.

  The pulp obtained above was subjected to a four-stage bleaching process of D-E-P-D as shown below. The first chlorine dioxide treatment (D) was prepared such that the pulp concentration was 10%, 0.4% of chlorine dioxide was added, and the treatment was performed at 70 ° C. for 40 minutes. Next, after washing with ion-exchanged water and dehydration, the pulp concentration was adjusted to 10%, 1% caustic soda was added, and alkali extraction treatment (E) was performed at 70 ° C. for 90 minutes. Next, after washing with deionized water and dehydration, the pulp concentration was adjusted to 10%, 0.5% hydrogen peroxide and 0.5% caustic soda were added successively, and the hydrogen peroxide treatment was performed at 70 ° C for 120 minutes ( P) was performed. Next, after washing with ion-exchanged water and dehydration, the pulp concentration was adjusted to 10%, 0.25% chlorine dioxide was added, and chlorine dioxide treatment (D) was performed at 70 ° C. for 180 minutes. Finally, bleached pulp having a whiteness of 85.3% was obtained after washing with deionized water and dehydration. Here, the total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp was 725 ppm.

The pulp slurry having a pulp concentration of 4% obtained above was beaten using a refiner so that the freeness was 450 ml (CSF). To the pulp slurry after beating, light calcium carbonate as a filler is added to 3.5% as paper ash, and rosin sizing agent as an internal sizing agent (trade name: Size Pine E, manufactured by Arakawa Chemical Industries) 0.7% and 2% aluminum sulfate were added to the pulp dry weight to prepare the stock. Using the paper stock prepared as described above, paper was made with a long net paper machine at a paper making speed of 500 m / min. Furthermore, with a two-roll size press apparatus, a 6% concentration oxidized starch (trade name: Ace C, manufactured by Oji Corn Starch Co., Ltd.) solution was applied and dried so that the total amount on both sides was 2 g / m ² (solid content). An uncoated paper having a weight of 64 g / m ² was obtained.

<Comparative Example 8>
As the comparative example 8, the example according to the Example of patent document 2 was implemented.
Autoclave using 40% eucalyptus, 20% oak, 30% acacia as wood chips, and 10% domestic wood (specifically, construction waste such as cypress or lawan, or thinned wood such as cedar or pine) After adding the cooking white liquor so that the liquid ratio was 4, the sulfidity was 28%, and the effective alkali was 17% (as Na ₂ O), kraft cooking was performed at a cooking temperature of 160 ° C. After completion of the kraft cooking, the black liquor was separated, and the obtained chips were defibrated with a high-concentration disintegrator, and then centrifugal dehydration and water washing were repeated three times with a filter cloth. Next, undistilled material was removed by a screen, and centrifugal dehydration was performed to obtain a cooked unbleached pulp having a copper number of 19.9.

After adding 2.0% NaOH to the pulp obtained by kraft cooking and adding ion-exchanged water so that the pulp concentration becomes 10%, oxygen gas is injected and 100 ° C is added. The treatment was performed at a gauge pressure of 5 kg / cm ² (0.49 MPa) for 60 minutes. The copper delignified pulp after washing and dehydration had a kappa number of 10.5.

The pulp obtained above was subjected to a four-stage bleaching process of ZEPD as shown below. The ozone treatment (Z) was prepared such that the pulp concentration was 40%, 0.5% ozone was added, and the treatment was performed at 40 ° C. Next, after washing with ion-exchanged water and dehydration, the pulp concentration was adjusted to 10%, 1% caustic soda was added, and alkali extraction treatment (E) was performed at 70 ° C. for 90 minutes.
Next, after washing with deionized water and dehydration, the pulp concentration is adjusted to 10%, 0.5% hydrogen peroxide and 0.5% caustic soda are sequentially added, and hydrogen peroxide treatment is performed at 70 ° C. for 120 minutes. (P) was performed. Next, after washing with ion-exchanged water and dehydration, the pulp concentration was adjusted to 10%, 0.25% chlorine dioxide was added, and chlorine dioxide treatment (D) was performed at 70 ° C. for 180 minutes. Finally, after washing and dehydration with ion-exchanged water, a bleached pulp having a whiteness of 85.1% was obtained. Here, the total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp was 703 ppm.

The pulp slurry having a pulp concentration of 4% obtained above was beaten with a refiner so that the freeness was 450 ml of Canadian Standard Freeness (CSF). Light calcium carbonate as a filler was added to the pulp slurry after beating so that the paper ash content was 3.5%. Further, rosin sizing agent (trade name: Size Pine E, manufactured by Arakawa Chemical Industry Co., Ltd.) 0.7% and aluminum sulfate 2% as an internal sizing agent were added to the absolute dry mass of the pulp to prepare a paper stock. Using the stock prepared as described above, paper was made with a long net paper machine at a paper making speed of 500 m / min. Furthermore, with a two-roll size press apparatus, a 6% concentration oxidized starch (trade name: Ace C, manufactured by Oji Corn Starch Co., Ltd.) solution was applied and dried so that the total amount on both sides was 2 g / m ² (solid content). An uncoated paper having a weight of 64 g / m ² was obtained.

  Various measurements and evaluations were performed as follows.

<Measurement of total content of linear alcohol (A) and linear fatty acid (B) of non-coated paper>
A dry sample 50 × 100 mm of the uncoated paper thus made was precisely weighed, 0.1 ml of concentrated hydrochloric acid (12 N) and 2 ml of chloroform were added, and sonication was performed for 10 minutes. The obtained extract was filtered through a membrane filter (pore diameter 0.2 μm). The above filtrate was used for analysis by high performance liquid chromatography. As an eluent, acetone = 50: 50 containing 0.1% of methanol: trifluoroacetic acid was used, and the flow rate was 1 ml / min. The column used was X Bridge C18, 250 mm × 4.6 mm manufactured by Waters. At D, the temperature was 30 ° C. and 2 μl of the filtrate was injected. Detector using a charged particles detector, linear alcohols (A) (higher alcohol _{C 24 H 49 OH, C 26} H 53 OH, C 28 H 57 OH) and linear fatty acids (B) (higher fatty acid C ₂₃ H ₄₇ COOH, C ₂₅ H ₅₁ COOH, and C ₂₇ H ₅₅ COOH) were detected, and the concentration in the sample was determined for each of them by the following formula, and the total was calculated. The peak area value of each component is a portion surrounded by the baze line and each peak, and the partially overlapping peak was obtained by peak separation by the perpendicular method of JIS K 0124.
Formula: Sample concentration (ppm) = Standard concentration (100 ppm) / Standard peak area value x Sample peak area value x 2 (ml) / (Sample mass (mg) / 1000)

<Measurement of total content of linear alcohol (A) and linear fatty acid (B) of pulp>
The pulp sent to the beating process was sampled and dried, and about 200 mg of dried pulp was precisely weighed, 0.1 ml of concentrated hydrochloric acid (12 N) and 2 ml of chloroform were added, and sonication was performed for 10 minutes. The obtained extract was filtered through a membrane filter (pore diameter 0.2 μm). The above filtrate was used for analysis by high performance liquid chromatography. The analysis method and the calculation method of the concentration in the sample were performed in the same manner as in the case of the measurement on the non-coated paper described above.

<Measurement of total abundance of linear alcohol (A) and linear fatty acid (B) on the surface of non-coated paper>
The measurement was performed by negative measurement (-ion detection) using TOF-SIMS (model: TRIFT4 manufactured by ULVAC-PHI). Measurement conditions were such that gold (Au ⁺ ) was used for the primary ion source, the measurement depth was about 1 nm, and the measurement area was 100 μm square.
The molecular ion peaks of the detected linear fatty acid (B), that is, higher fatty acids C ₂₃ H ₄₇ COOH, C ₂₅ H ₅₁ COOH, and C ₂₇ H ₅₅ COOH are mass numbers (m / z) 367, 395, respectively. The total value of these peak intensities (secondary ion counts) is divided by the total ion amount (total secondary ion count number of all peaks), and the divided value is multiplied by 10,000. The value was defined as the amount of the linear fatty acid (B) on the surface (calculation formula 1).
Further, the molecular ion peaks of the detected linear alcohol (A), that is, higher alcohols C ₂₄ H ₄₉ OH, C ₂₆ H ₅₃ OH, and C ₂₈ H ₅₇ OH, respectively, have a mass number (m / z) 351, The total value of these peak intensities (secondary ion counts) is divided by the total ion amount (the total value of secondary ion counts of all peaks), and the divided value is 10,000. The value obtained by multiplying by the amount was defined as the abundance of the linear alcohol (A) on the surface (calculation formula 2).
And each abundance of a linear alcohol (A) and a linear fatty acid (B) was added together, and it was set as these total abundance.
Formula 1: Surface linear fatty acid (B) content = {(I _{m / z 367} + I _{m / z 395} + I _{m / z 423} ) / I _total } × 10000
Formula 2: Surface linear alcohol (A) amount = {(I _{m / z 351} + I _{m / z 379} + I _{m / z 407} ) / I _total } × 10000

<Ash content of uncoated paper>
It was measured based on the ash content test method (525 ° C. combustion method) described in JIS P 8251: 2003.

<Measurement of coefficient of static friction>
W surface and W of a sample conditioned at 23 ° C. and 50% RH for 24 hours using a horizontal friction coefficient tester (trade name: “Amontons II” manufactured by MU Measurement Inc.) according to ISO 15359: 1999 The surfaces were overlapped and measured in the MD direction.

<Test 1 (running performance)>
This was carried out using a monochrome laser printer LP8600 manufactured by Seiko Epson Corporation in an environment of 23 ° C. and 50% RH. The sample was immediately placed on the manual feed tray of the copying machine after the package was opened, and was run 1000 sheets. The total number of running failures (idle running, paper jam and heavy running) at that time was counted as the number of running troubles.
The number of running defects is determined according to the following criteria and listed in Tables 1 and 2.
A: 0 to 5 sheets B: 6 to 10 sheets C: 11 sheets or more

<Test 2 (皺)>
A monochrome laser printer LP8600 manufactured by Seiko Epson Corporation was used and the test was performed in an environment of 28 ° C. and 85% RH. The sample was immediately placed on the manual feed tray of the copying machine after the package was opened, and was run 1000 sheets, and the number of wrinkles generated at that time was counted.
(Excellent) A → F (inferior)
A: 0 sheets B: 1 to 5 sheets C: 6 to 10 sheets D: 11 to 15 sheets E: 16 to 20 sheets F: 21 sheets or more The number of wrinkles generated is shown in Tables 1 and 2.

<Measurement of weight-weighted average fiber length of disaggregated pulp and fiber length distribution coefficient>
Uncoated paper was disaggregated by the pulp disaggregation method described in JIS P 8220, and the fiber length of the obtained disaggregated pulp was measured by a fiber lab manufactured by Kajaani, and the weight-weighted average fiber length (W) and the number average fiber length. (M) was determined. Then, the weight weighted average fiber length (W) and the number average fiber length (M) are substituted into the weight weighted average fiber length (W) / number average fiber length (M) formula to obtain the fiber length distribution coefficient. Calculated.

<Drainage pulp freeness>
The non-coated paper was disaggregated by the pulp disaggregation method described in JIS P 8220, and the freeness of the disaggregated pulp thus obtained was measured according to JIS P 8121.

<Evaluation of Chile>
The uncoated paper obtained above was visually judged for defects such as dust based on the following criteria.
A: There are no defects such as dust B: There are slight defects such as dust, but there is no problem in practical use C: There are many defects such as dust and is a problem in practical use

<Curl evaluation method>
Using an offset sheet-fed printing press (SM102, Heidelberg), printing four colors (printing order: black, indigo, red, yellow) (Fusion G EZ N type, manufactured by DIC) at a printing speed of 12,000 copies / h One hour after printing, MD curl was measured when 10 layers of chrysanthemum plates (636 mm × 939 mm) were suspended from the top.
A: Almost no curling occurs and the MD curl measurement value is within 10 mm, which is no problem at all.
B: Slight curling occurs, MD curl measurement value is within 11 to 30 mm, and there is no practical problem.
C: Curling occurs, and the MD curl measurement value is within 30 to 40 mm, which is a practical problem.
D: Curling occurs severely, and the MD curl measurement value is 40 mm or more, which is a serious problem.

<Comprehensive evaluation>
(Excellent) A → F (inferior)
A: Very good.
B: Good.
C: Although slightly inferior, it is generally good.
D: Although it is inferior, it is a level which is satisfactory practically.
E: Inferior and not practical.
F: Extremely inferior and not practical.

As is clear from Tables 1 and 2, the uncoated paper of each Example in which the total content of the linear alcohol (A) and the linear fatty acid (B) and the total abundance of the surface are both in a specific range are as follows: The occurrence of poor running and wrinkles was reduced. Further, the occurrence of curling when used for printing applications such as offset printing has been suppressed. Therefore, these non-coated papers have extremely excellent performance for printing applications such as electrophotography or ink-jet applications and offset printing used in copying machines and printers.

<Example 20>
(Manufacture of unbleached pulp (digestion process))
Using a Lo-solids digester (manufactured by Andritz), kraft cooking of hardwood chips consisting of Acacia Auricariformis: Eucalyptus maldrensis: Eucalyptus globulas = 40:40:20 (mass ratio) by Lo-solids cooking method did. Here, using white liquor having a sulfidity of 28 (distilled liquor), the white liquor addition rate is 10% per chip dry mass with respect to the chip supply system, 8% in the cooking zone and 8% in the washing zone, as the active alkali. 2% portion was added and the cooking temperature was 146 ° C. After the digestion of the chips after cooking, the washing process (filtered water / fresh water (100/0)), the screen process, and the washing process (filtered water / fresh water (100/0)) again, Bleached pulp) was obtained.

(Bleaching process)
To the unbleached pulp, 1.7% of caustic soda and 1.8% of oxygen per mass of dry pulp were added, and two-stage alkaline oxygen bleaching was performed under the conditions of a pulp concentration of 10% and 98 ° C. for 50 minutes. Here, caustic soda was added all at once in the first stage, and oxygen gas was added in 1.0% in the first stage and 0.8% in the second stage. The pulp after alkaline oxygen bleaching was washed in the washing step.

  After 1.2% sulfuric acid was added to the pulp after the alkali oxygen bleaching and the pulp concentration was 10% at 60 ° C. for 60 minutes, the pulp was washed in the washing step. Next, after adding 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp, and performing bleaching with medium concentration ozone / chlorine dioxide under conditions of pulp concentration 10%, 58 ° C. for 60 minutes, washing It was washed in the process. Next, 1.0% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp were added, and after alkali extraction under conditions of pulp concentration 10%, 60 ° C for 90 minutes, washing treatment was performed in the washing step. did. Next, 0.2% of chlorine dioxide per mass of absolutely dry pulp was added, and chlorine dioxide was bleached under conditions of a pulp concentration of 10%, 70 ° C. for 120 minutes, and then washed in the washing step to obtain a bleached pulp. The ISO whiteness of the obtained bleached pulp was 90.1%. Subsequently, it was washed with filtered water / fresh water (100/0) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 570 ppm.

(Beating process)
Double disk refiner (blade material) in which bleached pulp (concentration: 4.2% by mass) washed with filtered water / fresh water (100/0) is connected in parallel with three machines (the same blade is used) : Ni-Hard, blade width: 4.0 mm, groove width: 4.0 mm) and beaten to 445 ml of CSF to obtain a beaten pulp slurry.

(Paper making process)
To the beaten pulp slurry, alkenyl succinic anhydride sizing agent 0.04% (Fibran 81K / Arakawa Chemical Industries), aluminum sulfate 0.5% (vs. pulp, solid content conversion), and cationized starch ( Product name: Oji Ace K, manufactured by Oji Cornstarch Co., Ltd.) 1.0% (vs. pulp, solid content conversion) was added to the machine chest sequentially, and then the recovered white water and the above pulp slurry were mixed to produce calcium carbonate previously produced. The slurry (A) was added before the fan pump so that the content in the obtained base paper was 3.5%. Furthermore, 0.010% of a cationic acrylic resin (trade name: DR-3015, manufactured by Hymo Co., Ltd.) was added as a retention agent in front of the screen to prepare a paper stock (concentration: 1.01%).
This paper stock is formed with an on-top former at a J / W ratio of 0.995 and a paper making speed of 1,050 m / min, squeezed with three roll presses, dried with a single-stage dryer, and then on-machine. Surface sizing was performed with a specified two-roll size press. That is, a size press solution composed of 2% oxidized starch was applied to a solid content of 1.0 g / m ² , then dried with a two-stage dryer and passed through a machine calendar that would be on-machine specifications. A base paper having a water content of 4.5% and a basis weight of 47.4 g / m ² was obtained. The fiber orientation ratio was 1.02. At the time of papermaking, the collected white water was not discharged. That is, in the paper making process, white water / fresh water (100/0) was used for paper making.

(Preparation of pigment coating solution for undercoat coating layer)
Starch (trade name: Oji Ace A, manufactured by Oji Cornstarch Co., Ltd.) 4 as an adhesive to 100 parts of pigment in a pigment slurry made of heavy calcium carbonate (trade name: Hydrocurve 60, manufactured by Bihoku Flour Chemical Co., Ltd.) And 5 parts of styrene-butadiene copolymer latex (trade name: OJ-2000, manufactured by JSR) are added, and an antifoaming agent and a dye are sequentially added as auxiliary agents, and finally the solid content concentration is 67%. A pigment coating solution for an undercoat coating layer was prepared.

(Preparation of pigment coating solution for top coat layer)
Kaolin (trade name: Hydra Gloss 90, manufactured by Huber) is added to an aqueous solution in which 0.1 part of polyacrylic acid sodium (trade name: Aron T-50, manufactured by Toagosei Co., Ltd.) is added as a dispersant. 50 parts and 50 parts of heavy calcium carbonate (trade name: Hydrocurve 90, manufactured by Bihoku Powder Chemical Co., Ltd.) were added and dispersed with a Coreless disperser to prepare a pigment slurry. To 100 parts of the pigment slurry, 3 parts of oxidized starch (trade name: Oji Ace A, manufactured by Oji Cornstarch Co.), styrene-butadiene copolymer latex (trade name: OJ-2000, manufactured by JSR) 8 .4 parts, and further, an antifoaming agent and a dye were sequentially added as auxiliary agents to finally prepare a pigment coating solution for a top coating layer having a solid content concentration of 66.5%.

(Manufacture of coated paper)
Using a blade coater that supplies the pigment coating liquid for the undercoat coating layer to the base paper for coated paper (basis weight 47.4 g / m ² ) obtained above by the jet fountain method, Coating and drying were carried out so that the per dry coating amount was 7.5 g / m ² to obtain a double-sided undercoat coated paper. Subsequently, using a blade coater that supplies the pigment coating solution for the top coat layer to the double-sided undercoating paper and the coating solution by a jet fountain method, the dry coating amount per side is 9.5 g. / M ² was applied and dried to obtain a coated paper. The coated paper obtained in this manner was adjusted to the temperature, linear pressure, and paper feeding conditions with a multi-nip calender in which metal rolls and resin rolls were inclined, and the glossiness of white paper was 70%. Thus, a coated paper having a basis weight of 81.4 g / m ² was obtained.

<Example 21>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis = 50: 50 was used, and the amount of calcium carbonate slurry (A) added was determined to be 5.2% in the base paper. The same as Example 20, except that the addition amount of the cationic acrylic resin was 0.015%, the J / W ratio was 1.000, and the fiber orientation ratio was 1.07. Thus, a coated paper having a basis weight of 81.4 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1322 ppm.

<Example 22>
The use of a chip made of acacia mangum: acacia hybrid: eucalyptus grandis = 70:20:10 as a hardwood chip, the point where beating was performed up to 420 ml of CSF, and the content of calcium carbonate (A) in the base paper Coating with a basis weight of 81.4 g / m ^{2 in} the same manner as in Example 20, except that the amount was 7.7%, and the addition amount of the cationic acrylic resin was 0.020%. I got paper. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1935 ppm.

<Example 23>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis: eucalyptus globula = 80:10:10 was used. (70/30), beating up to 441 ml of CSF, calcium carbonate slurry (A) was added before the fan pump so that the content in the base paper was 7.7%, and colloidal silica (product Name: NP882, manufactured by Eka Chemicals Co., Ltd., average particle size (according to dynamic light scattering method, device: Nikkiso Co., Ltd., particle size / zeta potential measuring device “Nanotrack UPA-UZ152”): 3 nm) The amount added to the machine chest to be 0.05% and the addition amount of the cationic acrylic resin was 0.025%. , And except that a 930 m / min and machine speed, to obtain a coated paper having a basis weight of 81.4 g / ^{m 2} in the same manner as in Example 1. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2060 ppm.

<Example 24>
The point which used the chip | tip which consists of acacia mangum: eucalyptus maldrensis = 80: 20 as a hardwood chip | tip, the point which added caustic soda to the unbleached pulp, and made 1.2% per bone dry pulp mass, beating Except that the amount of cationic acrylic resin added was 0.025%, the J / W ratio was 1.005, and the fiber orientation ratio was 1.13. In the same manner as in Example 20, a coated paper having a basis weight of 81.4 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 3800 ppm.

<Example 25>
As a hardwood chip, a chip made of acacia mangum was used, added to unbleached pulp, caustic soda was made 1.4% per mass of dry pulp, beaten up to 379 ml of CSF, calcium carbonate The same procedure as in Example 20 was conducted except that the amount of slurry (A) added was such that the content in the base paper was 7.7% and the amount of cationic acrylic resin added was 0.025%. Thus, a coated paper having a basis weight of 81.4 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 3380 ppm.

<Example 26>
Content of base paper with the use of chips made of acacia mangum as hardwood chips, the point of beating up to 467 ml of CSF, and the addition of colloidal silica (trade name: NP882, manufactured by Eka Chemicals) without adding calcium carbonate The basis weight was 81.4 g / m in the same manner as in Example 20 except that the amount was 0.3% and the addition amount of the cationic acrylic resin was 0.020%. ² coated papers were obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2830 ppm.

<Example 27>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis = 50: 50, a point where beating was performed up to 440 ml of CSF, and without adding calcium carbonate, colloidal silica (trade name: NP882, A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that Eka Chemicals) was added to the machine chest so that the content in the base paper was 0.10%. . The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1313 ppm.

<Example 28>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis = 50: 50, a point where beating was performed up to 440 ml of CSF, and a calcium carbonate slurry (A) with a content of 6% in the base paper Example 20 except that colloidal silica (trade name: NP882, manufactured by Eka Chemicals Co., Ltd.) was added to the machine chest so that the content in the base paper was 0.10%. In the same manner, a coated paper having a basis weight of 81.4 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1313 ppm.

<Example 29>
A cooking process similar to that of Example 20 was performed except that a hardwood chip made of acacia mangeum was used.
Subsequently, the bleaching process was performed like Example 20, and the bleached pulp was obtained. The ISO whiteness of the obtained bleached pulp was 90.1%. Subsequently, a pulp with a solid content of 50% was obtained. Subsequently, it was dispersed with a pulper and washed with filtered water / fresh water (50/50) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1310 ppm. Beating was performed up to 450 ml of CSF.
Thereafter, the paper making process was performed in the same manner as in Example 20 except that the J / W ratio was 1.010 and the fiber orientation ratio was 1.18, and a coated paper having a basis weight of 81.4 g / m ² was obtained. It was.

<Example 30>
As a hardwood chip, a chip composed of acacia mangum: acacia hybrid: eucalyptus globulus = 60: 30: 10 was used, and the amount of calcium carbonate slurry (A) added was 7.7% in the base paper. A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that the amount was as follows. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2100 ppm.

<Example 31>
As a hardwood chip, a chip composed of acacia mangum: acacia hybrid: eucalyptus maldrensis = 60: 30: 10 was used, and the amount of calcium carbonate slurry (A) added was 7.7 in the base paper. A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that the amount became%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2100 ppm.

<Example 32>
As a hardwood chip, a chip composed of acacia mangum: eucalyptus maldrensis = 30: 70 was used, and the washing water used in the valveless filter before the bleaching pulp beating process was filtered water / fresh water (50/50). The point where the beating was performed up to 420 ml of CSF, the addition amount of the calcium carbonate slurry (A) was set to an amount that the content in the base paper was 5.0%, and the addition amount of the cationic acrylic resin was set to 0. A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that the content was changed to 022%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 670 ppm.

<Example 33>
As a hardwood chip, a chip made of acacia aurikariformis: eucalyptus maldolensis = 85: 15 was used, and the amount of calcium carbonate slurry (A) added was determined to be 8.5% in the base paper. A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that white water / fresh water (85/15) was used for paper making in the paper making process. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1300 ppm.

<Example 34>
The use of chips made of acacia mangum: acacia hybrid: eucalyptus grandis = 60:30:10 as hardwood chips, the point where beating was performed up to 350 ml of CSF, and the addition amount of calcium carbonate slurry (A) contained in the base paper Coating with a basis weight of 81.4 g / m ² was carried out in the same manner as in Example 20 except that the amount was 7.7% and that the addition amount of the cationic acrylic resin was 0.020%. Obtained paper. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1650 ppm.

<Example 35>
The use of a chip composed of acacia mangum: acacia hybrid: eucalyptus grandis = 60:30:10 as the hardwood chip, the point where beating was performed up to 590 ml of CSF, and the addition amount of calcium carbonate slurry (A) contained in the base paper Coating with a basis weight of 81.4 g / m ^{2 in} the same manner as in Example 20 except that the amount was 7.7% and that the addition amount of the cationic acrylic resin was 0.020%. I got paper. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 1650 ppm.

<Example 36>
(Preparation of pigment coating solution for coating layer)
Kaolin (trade name: Hydra Gloss 90, manufactured by Huber) is added to an aqueous solution in which 0.1 part of polyacrylic acid sodium (trade name: Aron T-50, manufactured by Toagosei Co., Ltd.) is added as a dispersant. 30 parts and 70 parts of heavy calcium carbonate (trade name: Hydrocurve 90, manufactured by Bihoku Powder Chemical Co., Ltd.) were added and dispersed with a Coreless disperser to prepare a pigment slurry. To 100 parts of the pigment slurry, 4 parts of oxidized starch (trade name: Oji Ace A, manufactured by Oji Cornstarch), styrene-butadiene copolymer latex (trade name: OJ-2000, manufactured by JSR) 6 .5 parts, and further, an antifoaming agent and a dye were sequentially added as auxiliary agents to finally prepare a pigment coating solution for a coating layer having a solid content concentration of 67%.

(Manufacture of coated paper)
Using a blade coater that supplies the coating liquid for the coating layer to the base paper for coated paper obtained in Example 20 (basis weight 47.4 g / m ² ), in a jet fountain system, The coated paper was obtained by coating and drying so that the dry coating amount per side was 8.3 g / m ² . The coated paper obtained in this way is adjusted to the temperature, linear pressure, and paper feeding conditions with a multi-nip calender in which metal rolls and resin rolls are inclined, and the blank paper glossiness is 50%. Thus, a coated paper having a basis weight of 64.0 g / m ² was obtained.

<Example 37>
As a hardwood chip, a chip made of acacia mangum: eucalypterita = 60: 40 was used, and the amount of calcium carbonate slurry (A) added was determined to be 7.7% in the base paper. A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as Example 20 except for the above. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 2100 ppm.

<Comparative Example 9>
The point which used the chip | tip which consists of acacia aurikariformis: eucalyptus maldolensis = 10: 90 as a broad-leaved tree chip | tip, and the point which made the addition amount of calcium carbonate (A) the quantity in which the content in a base paper will be 4.0% Except for the above, a coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 1. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 230 ppm.

<Comparative Example 10>
A chip made of acacia mangum was used as the hardwood chip, and a cooking process to a papermaking process were performed in the same manner as in Example 20.
However, in the bleaching step, the point that the amount of caustic soda added to the unbleached pulp was 1.0% per mass of the dry pulp was changed from Example 20. The ISO whiteness of the obtained bleached pulp was 90.1%. Further, it was made into a pulp with a solid content of 50%, then dispersed with a pulper, and washed with filtered water / fresh water (100/0) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 5200 ppm.
In the beating process, beating was performed up to 450 ml of CSF.
In the papermaking process, the amount of calcium carbonate slurry (A) added is changed to an amount that causes the content of the base paper to be 7.0%, and colloidal silica (trade name: NP882, manufactured by Eka Chemicals Co., Ltd.) is contained in the base paper. Was added to the machine chest so as to be 0.2%. Moreover, the addition amount of the cationic acrylic resin was changed to 0.020%. The stock concentration was 1.09%.
Then, a paper layer was formed in the same manner as in Example 20 except that the paper making speed was changed to 1,010 m / min. A coated paper of .4 g / m ² was obtained.

<Comparative Example 11>
A hardwood chip consisting of acacia mangum: eucalyptus maldrensis = 50: 50 was used as the hardwood chip, and the cooking process to the papermaking process were performed in the same manner as in Example 20. However, in the two-stage alkaline oxygen bleaching to be added to the unbleached pulp, the amount of caustic soda per mass of dry pulp is 2.0%, the point of beating up to 400 ml of CSF, and the valveless filter at the time of washing bleached pulp The point where the washing water is filtered water / fresh water (50/50), the addition amount of the cationic acrylic resin is 0.010%, and the addition amount of the calcium carbonate slurry (A) is 7.0% in the base paper. This point was changed from Example 20 in terms of the amount and the point of using white water / fresh water (85/15) for paper making in the paper making process. A coated paper having a basis weight of 81.4 g / m ² was obtained. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 800 ppm.

<Comparative Example 12>
As a hardwood chip, a chip made of acacia aurikariformis: eucalyptus maldrensis: eucalyptus grandis = 10: 70: 20, a point where beating was performed up to 450 ml of CSF, and an added amount of calcium carbonate slurry (A) A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that the content was 7.0%. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 220 ppm.

<Comparative Example 13>
(Manufacture of hardwood pulp (digestion process))
Using a Lo-solids digester (manufactured by Andritz), hardwood chips composed of Acacia mangum: eucalyptus grandis = 50: 50 (mass ratio) were kraft-cooked by the Lo-solids cooking method. Here, using white liquor having a sulfidity of 28 (distilled liquor), the white liquor addition rate is 10% per chip dry mass with respect to the chip supply system, 8% in the cooking zone and 8% in the washing zone, as the active alkali. 2% portion was added and cooking was performed at a cooking temperature of 146 ° C. After defibrating the chips after cooking, the washing process (filtered water / fresh water (50/50)), the screen process, and the washing process (filtered water / fresh water (50/50)) again, Bleached pulp) was obtained.

(Bleaching process)
To the unbleached pulp, 1.7% of caustic soda and 1.8% of oxygen per mass of dry pulp were added, and two-stage alkaline oxygen bleaching was performed under the conditions of a pulp concentration of 10% and 98 ° C. for 50 minutes. Here, caustic soda was added all at once in the first stage, and oxygen gas was added in 1.0% in the first stage and 0.8% in the second stage. The pulp after alkaline oxygen bleaching was washed in the washing step.

  After 1.2% sulfuric acid was added to the pulp after the alkali oxygen bleaching and the pulp concentration was 10% at 60 ° C. for 60 minutes, the pulp was washed in the washing step. Next, after adding 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp, and performing bleaching with medium concentration ozone / chlorine dioxide under conditions of pulp concentration 10%, 58 ° C. for 60 minutes, washing It was washed in the process. Next, 1.0% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp were added, and after alkali extraction under conditions of pulp concentration 10%, 60 ° C for 90 minutes, washing treatment was performed in the washing step. did. Next, 0.2% of chlorine dioxide per mass of absolutely dry pulp was added, and chlorine dioxide was bleached under conditions of a pulp concentration of 10%, 70 ° C. for 120 minutes, and then washed in the washing step to obtain a bleached pulp. The ISO whiteness of the obtained bleached pulp was 90.1%. Subsequently, it was washed with filtered water / fresh water (50/50) in a valveless filter. The total content of linear alcohol (A) and linear fatty acid (B) in the pulp sent to the beating process was 300 ppm.

(Beating process)
Double disk refiner (blade material: SUS, blade width: 1.0 mm, groove width) in which the above bleached pulp (concentration: 4.6 mass%) is connected in parallel with three machines (the blades are the same). 2.0 mm) and beaten up to 350 ml of CSF to obtain a beaten pulp slurry.

A coated paper having a basis weight of 81.4 g / m ² was obtained in the same manner as in Example 20 except that the pulp slurry obtained above was used.

<Comparative example 14>
(Production of hardwood pulp)
Using a Lo-solids digester (manufactured by Andritz), hardwood chips made of Eucalyptus grandis were kraft-cooked by the Lo-solids cooking method. Here, using white liquor having a sulfidity of 28, the white liquor addition rate is 10% per chip dry system, 8% in the digestion zone, and 2% in the washing zone, as the active alkali. And added at a cooking temperature of 146 ° C. After digesting the chips after cooking, unbleached pulp was obtained through a washing process, a screen process, and a washing process again.

  To the unbleached pulp, 1.7% of caustic soda per mass of dry pulp and 1.8% of oxygen were added, and two-stage alkaline oxygen bleaching was performed under the conditions of pulp concentration 10%, 98 ° C., 50 minutes. . Here, caustic soda was added all at once in the first stage, and oxygen gas was added in 1.0% in the first stage and 0.8% in the second stage. The pulp after alkaline oxygen bleaching was washed in the washing step.

  After 1.2% sulfuric acid was added to the pulp after the alkali oxygen bleaching and the pulp concentration was 10% at 60 ° C. for 60 minutes, the pulp was washed in the washing step. Next, 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp were added, and after carrying out medium concentration ozone / chlorine dioxide bleaching under conditions of pulp concentration 10%, 58 ° C., 60 minutes, washing It was washed in the process. Next, 1.0% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp were added, and after alkaline extraction under conditions of pulp concentration 10%, 60 ° C, 90 minutes, washing treatment in washing step did. Finally, 0.2% chlorine dioxide is added per mass of dry pulp, and chlorine dioxide bleaching is performed under the conditions of 10% pulp concentration, 70 ° C, 120 minutes, and then washed in the washing step. Obtained. The ISO whiteness of the obtained bleached pulp was 90.1%. The total content of the linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process was 120 ppm.

  Double disk refiner (blade material: Ni-Hard, blade width: 4.0 mm, groove) in which the above bleached pulp (concentration 4.2% by mass) is connected in parallel with three machines (the blades are the same) (Width: 4.0 mm) and beaten up to 550 ml of CSF.

(Production of softwood pulp)
Using a Lo-solids digester (manufactured by Andritz), conifer chips made of Douglas fir: radiata pine: caribbean pine = 1: 1: 1 (mass ratio) were craft-cooked by the Lo-solids cooking method. Here, using white liquor having a sulfidity of 25, the white liquor addition rate was divided into 10% per chip dry mass for the chip supply system, 8% for the digestion zone, and 2% for the cleaning zone as the active alkali. And the cooking temperature was 165 ° C. After digesting the chips after cooking, unbleached pulp was obtained through a washing process, a screen process, and a washing process again.

  To the unbleached pulp, 2.0% caustic soda and 1.8% oxygen per mass of dry pulp were added, and two-stage alkaline oxygen bleaching was performed under the conditions of a pulp concentration of 10%, 98 ° C., and 50 minutes. Here, caustic soda was added all at once in the first stage, and oxygen gas was added in 1.0% in the first stage and 0.8% in the second stage. The pulp after alkaline oxygen bleaching was washed in the washing step.

  After 1.2% sulfuric acid was added to the pulp after the alkali oxygen bleaching and the pulp concentration was 10% at 60 ° C. for 60 minutes, the pulp was washed in the washing step. Next, 0.5% ozone and 0.5% chlorine dioxide per mass of dry pulp were added, and after carrying out medium concentration ozone / chlorine dioxide bleaching under conditions of pulp concentration 10%, 58 ° C., 60 minutes, washing It was washed in the process. Next, 1.0% caustic soda and 0.1% hydrogen peroxide per mass of dry pulp were added, and after alkaline extraction under conditions of pulp concentration 10%, 60 ° C, 90 minutes, washing treatment in washing step did. Finally, 0.2% chlorine dioxide is added per mass of dry pulp, and chlorine dioxide bleaching is performed under the conditions of 10% pulp concentration, 70 ° C, 120 minutes, and then washed in the washing step. Obtained. The ISO whiteness of the obtained bleached pulp was 84.5%. The linear alcohol (A) and the linear fatty acid (B) in the pulp sent to the beating process were not detected.

  The above bleached pulp (concentration of 4.2% by mass) is introduced into one double disc refiner (blade material: 17 chrome, blade width: 4.8 mm, groove width: 4.8 mm) and beaten to 580 ml of CSF did.

(Preparation of base paper)
Light pulp calcium carbonate as a filler is added to a pulp slurry in which the beaten pulp is mixed so that softwood: hardwood = 50: 50 (mass ratio) so that the paper ash content is 6.5%. AKD sizing agent (trade name: Size Pine K-902, manufactured by Arakawa Chemical) 0.1% (vs. pulp, solid content conversion) and pre-gelatinized cationic starch (trade name: Oji Ace K, Oji Cornstarch) Manufactured) 0.5% (vs. pulp, solid content conversion) was added, and then a mixture of a cationic fatty acid amide and a nonionic wetting agent (trade name: Prosoft TQ-230, manufactured by Riken Green Co., Ltd.) with respect to the base paper mass A paper stock obtained by adding so as to have a content of 1% was prepared. Using this stock, a paper layer is formed by an on-top former at a J / W ratio of 0.995 and an operation paper making speed of 1010 m / min. After squeezing with three continuous shoe presses, squeezing with a roll press, The base paper for coated paper having a water content of 5.0% and a basis weight of 40.0 g / m ² was obtained.

(Manufacture of coated paper)
A pigment consisting of 50 parts of light calcium carbonate (trade name: FMT90, manufactured by Phimatech) and 50 parts of fine kaolin (trade name: Milagros OP, average particle size: 0.25 μm, manufactured by Engelhard) was used with a Coreless disperser. Dispersed in water to obtain a pigment slurry. 2. 10 parts (solid content) of styrene-butadiene copolymer latex (trade name: PA-9000, manufactured by Nippon A & L Co., Ltd.), pre-gelatinized oxidized starch (trade name: Oji Ace A, manufactured by Oji Corn Starch Co., Ltd.) 5 parts (solid content), an antifoaming agent, a fluorescent whitening dye, and a printability improver were added to finally prepare a coating liquid for a pigment coating layer having a solid content concentration of 64%. This coating liquid was coated on the base paper obtained above with a blade coater so that the dry coating amount per side was 8 g / m ² and dried to obtain a double-sided coated paper. The coated paper obtained was then smoothed with a 4-stage super calender consisting of a metal roll and a resin roll under the condition of a linear pressure of 100 kg / cm to obtain a coated paper having a basis weight of 56.0 g / m ^2. It was.

  Various measurements and evaluations of Examples 20 to 37 and Comparative Examples 9 to 14 were performed as follows.

<Measurement of total content of linear alcohol (A) and linear fatty acid (B) in base paper of coated paper>
Adhesive tape (Electric insulation tape manufactured by Sumitomo 3M Co., Ltd., trade name: “No. 5”) is applied to both sides of the coated paper of the present invention, and the adhesive tape is immediately peeled off from the coated paper to separate the base paper layer. I let you. And 200 mg of scraped base paper parts were scraped off with a razor, and it used as a sample for measuring content of a linear alcohol and a linear fatty acid.
It measured similarly to the measurement of the total content of the linear alcohol (A) and linear fatty acid (B) of the non-coated paper mentioned above using the said sample.

<Measurement of total content of linear alcohol (A) and linear fatty acid (B) of pulp>
The pulp sent to the beating process was sampled and dried, and about 200 mg of dried pulp was precisely weighed, 0.1 ml of concentrated hydrochloric acid (12 N) and 2 ml of chloroform were added, and sonication was performed for 10 minutes. The obtained extract was filtered through a membrane filter (pore diameter 0.2 μm). The above filtrate was used for analysis by high performance liquid chromatography. The analysis method and the calculation method of the concentration in the sample were performed in the same manner as in the measurement for the coated paper described above.

<Measurement of weight-weighted average fiber length and fiber length distribution coefficient of disaggregated pulp>
The coated paper was disaggregated by the pulp disaggregation method described in JIS P 8220: 1998, and the fiber length of the obtained disaggregated pulp was measured by Fiber Lab manufactured by Kajaani, and the weight-weighted average fiber length (W) and number average fiber were measured. The length (M) was determined. Then, the weight weighted average fiber length (W) and the number average fiber length (M) are substituted into the weight weighted average fiber length (W) / number average fiber length (M) formula to obtain the fiber length distribution coefficient. Calculated.

<Drainage pulp freeness>
The coated paper was disaggregated by the pulp disaggregation method described in JIS P 8220: 1998, and the freeness of the disaggregated pulp thus obtained was measured according to JIS P 8121-1995.

<Dimensional stability: Method for measuring drying shrinkage>
A coated paper sample conditioned according to JIS P-8111: 1998 is cut to a width of 2 mm so as to be orthogonal to the machine flow direction, and a thermomechanical analyzer (TMA-SS6000, Seiko Electronics Co., Ltd.) with a span of 20 mm in length. (Manufactured by Kogyo Co., Ltd.) is set so that a constant load of 5 gf is applied, and P (proportional) = 100, I (integral) = 1, D (differential) = 100 are set as the values of terminal probe PID control in the analyzer. The sample length before starting the temperature rise and starting the temperature rise when the temperature is increased from 23 ° C. to a set temperature of 300 ° C. at a heating rate of 200 ° C./min and held at the set temperature of 300 ° C. for 2 minutes. From the sample length after 5 minutes, the drying shrinkage percentage (%) is determined by the following formula.
Drying shrinkage (%) = {(sample length before temperature increase−sample length 1.5 minutes after start of temperature increase) / sample length before temperature increase} × 100

<Evaluation method for off-waist lines>
Using a rotary offset printing press (Mitsubishi Lithopia L-BT3-1100 / Mitsubishi Heavy Industries, Ltd.), a combination of a 4-color solid pattern on both sides, a 4-color solid pattern on one side and a light pattern on the other side in pink In the design, the printing speed was 330 m / min, the paper surface temperature at the outlet of the dryer was 120 ° C., the cooling roll after passing through the dryer was printed with cooling water at 10 ° C., and then continuously folded. After printing, the degree of off-ring wrinkles was visually evaluated according to the following criteria.
AA: Off-ring wrinkles do not occur.
A: A part of wide off wrinkles is generated, but the wrinkle depth is relatively shallow, and there is no problem at all.
B: Wide off-ring wrinkles occur throughout, but the wrinkle depth is relatively shallow, and there is no problem.
C: A large number of wide off-wrinkle wrinkles appearing throughout, and the wrinkle depth is moderate, which is a problematic level.
D: A level in which a large number of narrow off-wrinkles are generated and the wrinkle depth is deep, so that it becomes a big problem when wavy during bookbinding.

<Curl evaluation method>
Measurement and evaluation were performed in the same manner as the curl evaluation method for uncoated paper described above.

<Evaluation of Chile>
About the coated paper obtained above, defects, such as a dust, were visually judged on the same standard as the evaluation method of the dust of the non-coated paper mentioned above.

  As is apparent from Table 3, the coated paper of each example in which the total content of the linear alcohol (A) and the linear fatty acid (B) is in a specific range is excellent in dimensional stability and curl generation. It can be suppressed, and when it is used in an offset rotary printing press, the occurrence of off-roll wrinkles is reduced. Furthermore, when it is used on an offset sheet-fed press, the occurrence of curling after printing is suppressed, which is extremely excellent. Have good performance.

  According to the present invention, it is possible to provide a non-coated paper having a controlled coefficient of static friction, good dimensional stability, and reduced occurrence of running defects and wrinkles when used in a copying machine or printer. Moreover, according to this invention, the non-coated paper by which the generation | occurrence | production of the curl at the time of using for printing uses, such as offset printing, was suppressed can be provided. Furthermore, according to the present invention, when used in an offset rotary printing press, the occurrence of off-roll wrinkles is reduced, dimensional stability is good, and when used in an offset sheet-fed printing press, It is possible to provide a coated paper that suppresses the occurrence of curling.

Claims (11)

A coated paper comprising at least one coating layer containing a pigment and an adhesive on a base paper,
In the base paper, a monovalent linear alcohol having a carbon number selected from the group consisting of 24, 26, and 28, and a carbon number selected from the group consisting of 24, 26, and 28 carbon atoms. coated papers total content of the linear fatty acid is is 180 ～2000Ppm with respect to the total weight of the base paper. The coated paper according to claim 1, which is for offset printing. The freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 380 to 550 ml,
JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60-0.90 mm, and
The coated paper according to claim 1 or 2 , wherein the fiber length distribution coefficient is 1.30 to 1.90. The freeness measured according to JIS P 8121-1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 400 to 500 ml,
JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and
The coated paper according to any one of claims 1 to 3, which has a fiber length distribution coefficient of 1.30 to 1.60. A monovalent linear alcohol having a carbon number selected from the group consisting of 24, 26, and 28, and a straight chain having a carbon number selected from the group consisting of 24, 26, and 28 The total content of fatty acids is 215 to 2000 ppm based on the weight of the whole paper, and
A non-coated paper having a total abundance of the linear alcohol and the linear fatty acid on the surface measured by a time-of-flight secondary ion mass spectrometer of 15 or less. The non-coated paper according to claim 5, which is used for sheet feeding. The non-coated paper according to claim 5 or 6, which is used for electrophotography or inkjet. At least one selected from the group consisting of calcium carbonate, colloidal silica and calcined kaolin within a range in which the ash content measured by the ash content test method (525 ° C. combustion method) described in JIS P 8251: 2003 is 35% by mass or less. The non-coated paper as described in any one of Claims 5-7 containing these substances. The freeness measured according to JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 380 to 550 ml,
JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60-0.90 mm, and
The uncoated paper according to any one of claims 5 to 8, which has a fiber length distribution coefficient of 1.30 to 1.90. The freeness measured according to JIS P 8121: 1995 of the disaggregated pulp obtained by disaggregation by the pulp disaggregation method described in JIS P 8220: 1998 is 350 to 550 ml,
JAPAN TAPPI No. The weight-weighted average fiber length measured by the pulp fiber length test method in the optical automatic measurement method defined in 52: 2000 is 0.60 to 0.80 mm, and
The uncoated paper according to any one of claims 5 to 8, wherein the fiber length distribution coefficient is 1.30 to 1.60. The non-coated paper according to any one of claims 5 to 10 , wherein a static friction coefficient is 0.40 to 0.70.