JP4929778B2 - Bulky paper manufacturing method - Google Patents

Description

  The present invention relates to a bulky paper containing a bulking agent for paper and a method for producing the same.

  Comic books and paper books have rapidly spread, reflecting the recent separation of type. Along with this, paper is also required to be lighter. Here, the weight reduction of paper refers to weight reduction while maintaining the thickness of the paper, that is, increase in bulk (lower density). Now that environmental problems are being sought, paper weight reduction is an unavoidable problem in making effective use of paper pulp made from forest resources.

  Various techniques for making paper bulky have been conventionally studied in terms of raw materials to be blended in paper and equipment in paper machines and coating machines. The study of raw materials includes the study of raw material pulp and filler to be blended into paper, and further the blending of expandable particles. The study of equipment includes the study of technology for processing calendars at low linear pressure. Can be mentioned. As a recent new technique for making paper bulky, there is a technique for making a paper bulky by containing a so-called paper bulking agent in the paper. However, the technology related to these paper bulking agents is that paper bulking agent is added and mixed in the paper stock as a raw material for paper making before paper machine inlet, and this paper is ejected from the inlet onto the wire to make paper. This is a technique for making paper bulky by containing a paper bulking agent therein, and is a bulky technique based on what is called internal addition.

  However, when a paper bulking agent is used internally, problems similar to those conventionally known for other internal additives occur. That is, the fixing of the paper bulking agent to the pulp fiber is mainly based on the adsorption action to the pulp fiber and the filtration action by the wet paper layer formed on the wire, so the fixing is not strong, and the shear force and With dehydration on the wire due to suction force, the paper bulking agent easily falls off the pulp fiber and passes through the wire, and the one-pass yield of the paper bulking agent is low. Further, the bulking agent for paper that has passed through the wire gradually accumulates in white water circulating in the papermaking system, and problems such as generation of dirt and foaming occur in the white water system. Furthermore, since the one-pass yield of the paper bulking agent is low, the target paper bulking agent content in the paper cannot be obtained immediately after the start of papermaking, and a non-standard product whose paper density does not reach the target value occurs. There is a problem.

  The technique disclosed in Patent Document 2 can be cited as a technique for incorporating a paper bulking agent into paper by a method that does not depend on the internal addition method. Patent Document 2 has a problem of providing a printing paper that has sufficient bulkiness and printability and is excellent in suppleness and touch, and a filler having a pore volume of 1.5 to 4.0 mL / g is 3 per mass of paper. ~ 10% by mass, 2 ~ 6g / m2 of surface treatment agent containing softening chemical, water-soluble polymer and surface sizing agent is applied, density is 0.50 ~ 0.65g / cm3, Clark stiffness in cross direction is Printing paper that is 30-55 cm3 / 100 is disclosed. In this technology, softening chemicals included in the category of bulking agents for paper include gate roll coaters, 2-roll size presses, blade metering size presses, rod metering size presses, blade coaters, bar coaters, rod blade coaters, air knives. Apply to the surface of base paper with on-machine coating equipment such as coater. This base paper is a dried paper that is compressed and squeezed in the press process and then dried in the pre-dryer process, and the moisture content of the pulp is already several percent. It is a formed paper with high density. Therefore, even if a softening chemical is applied to such a base paper and contained in the paper, there is a big problem that the effect of making the paper bulky is low.

  As described above, it has been demanded to establish a method for using a paper bulking agent or a method for producing a bulky paper, which can solve various problems in the conventional internal addition method and surface coating method of the paper bulking agent.

Japanese Patent No. 3128248 JP 2005-256205 A

  The problem to be solved by the present invention is that in the production of bulky paper containing a paper bulking agent, the one-pass yield on the wire of the paper bulking agent is high, there are few problems of white water-based stains and foaming, and The object of the present invention is to provide a method for producing a bulky paper that has a short time from the start of adding a bulking agent to obtaining a bulky paper product and has a small operation loss, and to provide a bulky paper excellent in bulkiness obtained by this production method.

  On a long net wire of a paper machine having a long net portion, a bulking agent for paper is sprayed by a spray device onto a wet paper layer in the formation process on the wire and contained in the paper.

  On the long net wire of a paper machine having a long net portion, the paper bulk agent is sprayed onto the wet paper layer in the formation process on the wire by a spray device and contained in the paper, thereby the paper bulk agent on the wire. Yields a high one-pass yield, reduces white water stains and foaming problems, and stabilizes paper machine operations. In addition, since the time from the start of adding the bulking agent for paper to the production of a bulky paper product is short, the amount of paper with a density outside the standard can be reduced, and the bulky paper can be produced efficiently. Moreover, compared with the method of apply | coating the bulking agent for paper with an on-machine coating equipment and manufacturing a bulky paper, it is excellent in the bulkiness effect of paper with the same content rate of the bulking agent for paper.

  In the present invention, the bulking agent for paper is sprayed onto the wet paper layer in the formation process on the wire by the spray device on the long-mesh wire of the long-mesh paper machine or the paper machine having the long-mesh part, and is contained in the paper. This is an essential requirement. Specific examples of the paper machine having a long net portion include an on-top twin-wire paper machine in which a top wire is arranged on a long net, and a multilayer paper machine in which a long net is arranged after at least one circular net. It is done. The stock sprayed from the slice lip of the stock inlet onto the long-mesh wire is gradually dehydrated by a dewatering element such as a forming board, table roll, foil blade or suction box placed under the wire, and a wet paper layer is formed on the wire. After forming the film, it enters the next pressing process at a moisture content of about 80 to 85%. The wet paper layer in the process of formation is a wet paper layer in a state where pulp fibers are stacked on the long net by dehydration from after the slice lip of the stock inlet to the end of the long net to form a layer. It points to that.

  The spray device for spraying the paper bulking agent is not particularly limited, and a known spray device can be used. For example, 1 fluid nozzle spray, 2 fluid nozzle spray, etc. are mentioned.

  The spray equipment needs to be installed at a position where the bulking agent for paper can be sprayed uniformly in the entire width direction of the wet paper layer in the process of forming on the long net. Depending on the paper making speed of the paper machine, the basis weight of the paper to be made, the amount of paper bulking agent added, etc., the amount of spraying of the paper bulking agent varies. Can be installed. Further, the vertical positional relationship between the long mesh and the spray device is that the spray device is installed at a position above the long mesh. That is, the bulking agent for paper is sprayed on the felt surface side of the paper.

The spray device is placed immediately after a slice liter flop exit the stock inlet drainage line (D ry L ine, solid concentration of about 7%) between. The water drainage line occurs at a position where free water on the surface of the wet paper layer is depleted and the free water on the wet paper layer surface disappears. This is the boundary line that appears dull on the side with little water and little water. If the paper bulking agent is sprayed after the water break line with the spray equipment, the dehydration proceeds considerably and the solid content density of the wet paper layer is higher than when spraying before the water break line. The one-pass yield of the bulking agent for paper is improved, but the tendency for the bulking agent for paper to be unevenly distributed in the Z direction of the wet paper layer is increased, and there is more presence on the felt side of the paper. The bulking effect of the bulking agent tends to decrease. In addition, even if it is between the slicing lip outlet immediately after the slicing lip exit, if it is close to the slicing lip exit, the amount of water to be dehydrated increases, and the paper bulking agent sprayed with dehydration tends to pass through the wire. Therefore, it is more preferable that it is close to the drain line.

  The solid content concentration of the paper bulking agent sprayed by the spray device is not particularly limited, but it is preferably 20% or less in order to spray the wet paper layer on the long web as uniformly as possible. .

  Specific examples of the bulking agent for paper include oil-based nonionic surfactants, sugar alcohol-based nonionic surfactants, sugar-based nonionic surfactants, polyhydric alcohol-type nonionic surfactants, polyhydric alcohols. And fatty acid ester compound, higher alcohol or polyoxyalkylene adduct of higher fatty acid, polyoxyalkylene adduct of higher fatty acid ester, polyoxyalkylene adduct of polyhydric alcohol and fatty acid ester compound, fatty acid polyamidoamine, linear Examples include fatty acid monoamides and unsaturated fatty acid diamidoamines.

    This paper bulking agent is exemplified in the patent literature as follows. Paper bulking agent described in Japanese Patent No. 3128248, paper bulking agent described in Japanese Patent No. 3453505, paper bulking agent described in Japanese Patent No. 3482336, paper bulking agent described in Japanese Patent No. 3576962, Patent No. No. 3482337, a paper bulking agent described in Japanese Patent No. 2971447, a paper making paper quality improving agent described in Japanese Patent No. 3283248, a drying efficiency improving agent described in Japanese Patent No. 3338333, and a Japanese Patent No. 3387036. Smoothness and air permeability improver described in Japanese Patent No. 3517200, additive for papermaking described in Japanese Patent No. 3517200, paper quality improver described in Japanese Patent Laid-Open No. 2001-248100, and paper quality improvement described in Japanese Patent Laid-Open No. 2003-336196 Paper quality improver described in JP 2004-052216 A, paper quality improver described in JP 2005-187989, paper quality improver described in JP 2004-107865, JP 2004-091950 A The paper quality improver described in JP-A-2005-299010, the paper quality improver described in JP-A-2005-299011, JP-A-20 Paper quality improver described in Japanese Patent Application Laid-Open No. 05-299012, paper bulking agent described in Japanese Patent Application Laid-Open No. 2005-089953, paper opacifying agent described in Japanese Patent Application Laid-Open No. 2000-273792, waste paper described in Japanese Patent Application Laid-Open No. 2002-129497 Recycling additive, waste paper recycling additive described in JP-A-2002-275786, waste paper recycling additive described in JP-A-2002-294586, bulking agent described in JP-A-2002-294594, JP-A 2003 -96692 paper bulking agent, JP 2003-96693 bulking agent, JP 2003-96694 JP waste paper recycling additive, JP 2003-96695 JP waste paper recycling additive Agent, paper thickness improver described in JP2003-171897, paper bulking agent described in JP2003-247197, paper bulking agent described in JP2003-253588, JP2003-253589 Paper bulking agent described in the publication, paper bulking agent disclosed in JP2003-253590, paper density reducing agent described in JP2003-328297, paper low density described in JP2003-313799A Agent, Japanese Patent Application Laid-Open No. 2004-11058 Paper making additives described in Japanese Laid-Open Patent Publication No. 2004-27401, paper density reducing agents described in Japanese Patent Application Laid-Open No. 2004-27401, paper density reducing agents described in Japanese Patent Application Laid-Open No. 2004-115935, paper described in Japanese Patent Application Laid-Open No. 2004-76244 Bulking agent for paper, paper modifier described in JP-A-2004-176213, paper softening agent described in Japanese Patent No. 3521422, bulky softening agent described in JP-A-2002-275792, JP-A 2002- A paper bulking sizing agent described in Japanese Patent No. 285494, a paper bulking agent described in Japanese Patent Laid-Open No. 2003-286692, a paper bulking agent composition described in Japanese Patent Laid-Open No. 2004-270074, Bulkiness agent for papermaking, opacity improver described in JP-A-2003-221799, additive for paper described in JP-A-2004-308095, bulking agent described in JP-A-2005-042278, JP-A-2005-042279 Bulking agent described in Japanese Patent Publication No. 2005-060891, a paper bulking agent described in Japanese Patent Publication No. 2005-060891, a paper density reducing agent described in Japanese Patent Publication No. 2005-082943, and paper reforming described in Japanese Patent Publication No. 2005-082949. Agent.

  The bulking agent for paper referred to in the present invention is a general term for compounds having both a hydrophobic group and a hydrophilic group in a molecule, which can reduce the density of paper when paper is added internally to the stock. . In addition to the bulking agent as described in the above-mentioned patent document, the papermaking paper quality improver, drying efficiency improver, smoothness and air permeability improver, papermaking additive, paper quality improver, paper opacifier, waste paper recycling Additives, paper thickness improvers, paper densifying agents, paper modifiers, paper softening agents, bulky softening agents, papermaking bulky sizing agents, and the like.

  Since the bulking agent for paper becomes a factor that inhibits binding between pulp fibers, generally, the higher the content of the bulking agent for paper in the paper, the lower the strength of the paper. Moreover, even if the amount of addition is increased beyond a certain level, the effect is often seen to reach its peak. For this reason, it is preferable to contain the bulking agent for paper in the range of 0.1 to 20% by weight of the solid pulp solid weight, and the bulky effect is sufficient without changing the paper quality other than bulk. It is more preferable to make it contain in 0.2 to 5.0 solid content weight% in order to make it express.

  The raw pulp of bulky paper to be made by the production method of the present invention is not particularly limited, and chemical pulp, chemical pulp (conifer bleached kraft pulp (NBKP), hardwood bleached kraft pulp (depending on paper type, brand, quality) LBKP), mechanical pulp (groundwood pulp (GP), refiner mechanical pulp (RGP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), etc.), DIP, etc. be able to.

  The paper making method of the bulky paper of the present invention includes an acid paper making in which the paper making pH is in the acidic region, a pseudo neutral paper making in which the paper making pH is in the pseudo neutral region, and a neutral paper making in which the paper making pH is in the neutral region. Either papermaking paper or alkaline papermaking in which the papermaking pH is made in an alkaline region may be used. It is also possible to apply an alkaline agent to the surface of the acid base paper made by acid paper making to make a neutral paper.

  The bulky paper of the present invention may be blended with or without a filler, but a filler may be blended from the viewpoint of increasing opacity and post-printing opacity, and from the viewpoint of reducing back-through. When blending a filler, the filler generally used in acidic papermaking, neutral papermaking, or alkaline papermaking can be used, and is not particularly limited. For example, for pseudo neutral paper, neutral paper, alkaline paper, clay, calcined kaolin, deramikaolin, heavy calcium carbonate, light calcium carbonate, light calcium carbonate-silica composite, magnesium carbonate, barium carbonate, titanium dioxide, zinc oxide , Silicon oxide, amorphous silica (white carbon, etc.), aluminum hydroxide, calcium hydroxide, magnesium hydroxide, zinc hydroxide and other inorganic fillers, urea-formalin resin, polystyrene resin, phenol resin, micro hollow particles, etc. Organic fillers are used alone or in appropriate combination of two or more. Further, in acidic papermaking, a filler obtained by removing acid-soluble ones from the filler used in the neutral papermaking is used, and these are used alone or in combination of two or more as appropriate.

  In the production of the bulky paper of the present invention, various internally added sizing agents may be blended. Various nonionic, cationic or amphoteric yield improvers, freeness improvers, paper strength improvers, and the like used in the past are appropriately selected and used as required. Is done.

  Further, for example, sulfuric acid bands, aluminum chloride, sodium aluminate, basic aluminum compounds such as basic aluminum chloride and basic polyaluminum hydroxide, water-soluble aluminum compounds such as water-degradable alumina sol, sulfuric acid A polyvalent metal compound such as ferrous sulfate or ferric sulfate, silica sol, or the like may be internally added.

  Other starches for papermaking, various starches, polyacrylamide, urea resin, melamine resin, epoxy resin, polyamide resin, polyamide, polyamine resin, polyamine, polyethyleneimine, vegetable gum, polyvinyl alcohol, latex, polyethylene oxide, hydrophilic cross-linked polymer Various compounds such as particle dispersions and derivatives or modified products thereof can be used.

  Furthermore, paper additives such as dyes, fluorescent brighteners, pH adjusters, antifoaming agents, pitch control agents, slime control agents and the like can be appropriately added depending on the intended use.

  A surface treatment agent may be applied to the bulky paper obtained by the production method of the present invention, if necessary. Examples of the components contained in the surface treatment agent include water-soluble polymer substances used for the purpose of improving the surface strength of paper, and surface sizing agents used for the purpose of improving the surface size of paper. . Examples of water-soluble polymer substances include raw starch, oxidized starch, esterified starch, cationized starch, heat-modified starch, enzyme-modified starch, aldehyde-modified starch, hydroxyethylated starch and other modified starches, carboxymethylcellulose, hydroxyethylcellulose, Cellulose derivatives such as methylcellulose, modified alcohols such as polyvinyl alcohol and carboxyl-modified polyvinyl alcohol, styrene butadiene copolymer, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, polyacrylic acid ester, Polyacrylamide or the like can be used alone or in combination. As the surface sizing agent, known surface sizing agents such as styrene acrylic acid, styrene maleic acid, olefinic compounds, and cationic surface sizing agents can be used alone or in combination.

  The press line pressure is used within the normal operating range. When applying a surface treatment agent, there are no particular limitations on the components of the surface treatment agent, and there is no restriction on the type of size press. A press or the like can be used as appropriate. The calendar is used at a linear pressure within the normal operating range. From the viewpoint of increasing the bulk, a low linear pressure or a bypass is preferable as long as the smoothness of the paper can be maintained, and a soft carrier is used rather than a normal calendar. A render is preferred.

  The method for producing bulky paper of the present invention is a method for spraying a paper bulking agent onto a wet paper layer using a spray device. Therefore, compared with the conventional production method in which a paper bulking agent is internally added, The one-pass yield on the wire of the bulking agent is high. As this effect, the problem of white water-based dirt and foaming is reduced, and the operation of the paper machine is stabilized. In addition, since the time from the start of adding the bulking agent for paper to the production of a bulky paper product is short, the amount of paper with a density outside the standard can be reduced, and the bulky paper can be produced efficiently.

  The use of the bulky paper produced by the present invention is not particularly limited, but it is suitable as, for example, offset printing paper and writing paper. In addition, it can also be used as a base paper for information recording paper such as letterpress printing paper, electrophotographic paper, ink jet recording paper, thermal recording paper, pressure sensitive recording paper, PPC paper, form paper and the like. It can also be used as a base paper for coating, newsprint, paperboard, and white paperboard.

  Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto. In addition, all% in an example shows solid content weight%. The addition rate of the bulking agent for paper is the solid content weight% of the bulking agent with respect to the solid pulp solids weight.

The following items were measured and evaluated for the bulky paper produced in the examples and comparative examples.
(1) Basis weight: Based on JIS P 8124.
(2) Thickness / density: Conforms to JIS P 8118.
(3) Content of paper bulking agent in paper: The bulky paper obtained was analyzed by pyrolysis gas chromatography, and the content of bulking agent in the paper (weight% solid content) was determined from a calibration curve of bulking agent prepared in advance. ) Was calculated.
(4) Bulking agent one-pass yield: Calculated from the following formula.
Bulking agent one-pass yield = 100 × (bulk agent content in paper%) / (bulking agent addition ratio%)

[Example 1]
LBKP (freeness CSF = 400 ml) was used as the pulp content. Sulfate band is 2.0% by weight (50% by weight sulfate band product), 1.2% by weight of cationized starch and 0.1% by weight of alkyl ketene dimer (AKD) sizing agent per pulp solids weight. Paper was added to the paper and mixed using a paper web tester with a wire width of 50 cm at a paper making speed of 20 m / min and a basis weight of 70 g / m ² . At this time, two fluid nozzle sprays are arranged at equal intervals in the width direction immediately before the water break line on the wire of the long paper machine, and the spray amount is adjusted so that the addition rate of the bulking agent becomes 0.3 solid weight%. Then, a bulking agent for paper (trade name: KB115, manufactured by Kao Corporation) was sprayed at a solid content concentration of 0.45%. It was processed in the press part following the wire part of the long paper machine, and dried in the dry part to obtain a bulky paper. The basis weight, thickness, density, and bulking agent content of the bulky paper were measured. The results are shown in Table 1.

[Example 2]
Bulky paper was obtained in the same manner as in Example 1 except that the two-fluid nozzle spray was arranged at the midpoint between the water break line on the wire and the slice lip, and the spray amount was adjusted so that the bulking agent addition rate was 0.6%. .

[Example 3]
Bulky paper was obtained in the same manner as in Example 1 except that the two-fluid nozzle spray was arranged immediately after the slice lip on the wire and the spray amount was adjusted so that the addition rate of the bulking agent was 0.9%.

[Comparative Example 1]
LBKP (freeness CSF = 400 ml) was used as the pulp content. Per weight of pulp solids, bulking agent for paper (trade name: KB115, manufactured by Kao Corporation) is 0.3% solids by weight, sulfuric acid band is 2.0% by weight (sulfuric acid band product with 50 solids weight), cationized starch 1.2% solids by weight, alkyl ketene dimer (AKD) sizing agent was added at 0.1% solids by weight, and the paper stock was mixed to make a paper speed of 20m / and papermaking min grammage of 70 g / m ² to a target. It was processed in the press part following the wire part of the long paper machine, and dried in the dry part to obtain a bulky paper. Table 1 shows the results obtained by measuring the basis weight, thickness, density and bulk content of the bulky paper in the paper.

[Comparative Example 2]
Bulky paper was obtained in the same manner as in Comparative Example 1 except that the bulking agent addition rate was 0.6% by solid weight.

[Comparative Example 3]
Bulky paper was obtained in the same manner as in Comparative Example 1 except that the bulking agent was added at 0.9 solid weight%.

[Comparative Example 4]
LBKP (freeness CSF = 400 ml) was used as the pulp content. Sulfate band is 2.0% by weight (50% solid weight sulfate band product), cationized starch is 1.2% solids by weight, and alkylketene dimer (AKD) sizing agent is 0.1% solids by weight per pulp solids weight. Using a paper stock added and mixed in this way, using a test screen paper machine with a wire width of 50 cm, paper making is performed with a target of paper making speed of 20 m / min basis weight of 70 g / m ² , drying with a predryer, and then 2-roll size press Was used to apply a dilute solution of a bulking agent (trade name: KB115, manufactured by Kao Corporation) and dried with an after dryer to obtain a bulky paper. In addition, the amount of liquid absorption with a size press was measured in advance, and the concentration of the bulking agent diluent was adjusted so that the coating amount of the paper bulking agent was 0.3 solids weight% per pulp solids weight.

[Comparative Example 5]
Bulky paper was obtained in the same manner as in Comparative Example 1 except that the coating amount of the bulking agent was adjusted to 0.6% by weight per pulp solids weight.

[Comparative Example 6]
Bulky paper was obtained in the same manner as in Comparative Example 1 except that the coating amount of the bulking agent was adjusted to 0.9% by weight per pulp solids weight.

  The following can be understood from the results shown in Table 1. When compared with Example 1 and Comparative Example 1, Example 2 and Comparative Example 2, and Example 3 and Comparative Example 3 with the same bulking agent addition rate, the spray device was placed on the long net wire of the paper machine having the long net part. The bulky paper obtained by spraying the bulking agent for paper onto the wet paper layer has a higher one-pass yield of the bulking agent than the bulky paper obtained by adding the bulking agent by internal addition. The bulking agent content in the paper is high, and a low density bulky paper can be obtained. When compared with Example 1 and Comparative Example 4, Example 2 and Comparative Example 5, Example 3 and Comparative Example 6 with the same bulking agent addition rate, the spray device was placed on the long mesh wire of the paper machine having the long mesh portion. Compared to the bulk paper obtained by spraying the paper bulk agent onto the wet paper layer, the bulk paper obtained by applying the paper bulk agent using 2-roll size fres The one-pass yield is naturally very high, and the bulking agent content in the paper is high, but the density does not decrease much.

  Table 2 shows spray spraying examples 1 to 3 ("1" in FIG. 1), internal addition comparative examples 1 to 3 ("2" in FIG. 1), and surface coating comparative examples 4 to 6 ( [3] in FIG. 1 is a diagram showing the relationship between the content of the bulking agent for paper in the paper and the density of the bulky paper. What applied the bulking agent becomes another curve, and a density becomes a high position. Therefore, the distribution in the paper layer of the paper bulking agent contained in the paper by spraying is considered to be close to the internal addition method. In the case of size press coating, if the bulking agent liquid is applied to the surface of the paper once dried with a pre-dryer to form a bond between pulp fibers to form a paper layer, the paper will swell slightly even if the bulking agent penetrates inside the paper. This is considered to be because the action of cleaving the bond between the pulp fibers and interposing a bulking agent between the pulp fibers to lower the density is small. Moreover, even in an experiment on a test paper machine with a low paper speed, these results are the same, so in an actual paper machine with a very high paper speed, the swelling time of the paper is extremely short, and a bulk paper is produced by applying a bulking agent. However, the bulkiness effect is small, and it is considered that there is almost no practical value.

It is a figure which shows the relationship between the density | concentration in the paper and the density of bulky paper in Examples 1-3 of spraying, Comparative Examples 1-3 of the internal addition method, and Comparative Examples 4-6 of surface coating.

Explanation of symbols

1: Bulk paper obtained by spraying a paper bulk agent 2: Bulk paper obtained by internally adding a paper bulk agent 3: Bulk paper obtained by applying the paper bulk agent with a size press

Claims (2)

  A paper bulking agent is sprayed between the slice lip of the stock inlet by the spray device to the wet paper layer in the forming process on the wire on the long net wire of the paper machine having the long net part, and until the water break line is reached. A method for producing a bulky paper, characterized in that it is contained therein.   2. The method for producing a bulky paper according to claim 1, wherein a bulking agent for paper is sprayed immediately before the water break line and contained in the paper.

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