WO2003083211A1

WO2003083211A1 - Bulky paper

Info

Publication number: WO2003083211A1
Application number: PCT/JP2003/003720
Authority: WO
Inventors: Tomoyuki Nakano; Yasunori Nanri; Reiji Ohashi; Mitsutoshi Nakamura
Original assignee: Nippon Paper Industries, Co., Ltd.
Priority date: 2002-03-28
Filing date: 2003-03-26
Publication date: 2003-10-09
Also published as: JPWO2003083211A1; US20050178517A1; AU2003227212A1; CA2481210A1

Abstract

A bulky paper which contains a polyacrylamide having a charge amount as measured at pH 2 of 2.0 meq/g or smaller and a charge amount as measured at pH 12 of 2.0 meq/g or smaller. It may optionally further contain amorphous silica or an amorphous silicate each having a bulk specific gravity of 0.3 g/mL or smaller as a filler and contain a bulking agent comprising a fatty acid polyamide compound or an ester of a polyhydric alcohol with a fatty acid. It may further contain a mercerized pulp or crosslinked pulp. The bulky paper containing the polyacrylamide has a relative bond area up to 1.2 times the relative bond area of a bulky paper containing no polyacrylamide. The bulky paper has improved paper strengths, e.g., tensile strength, without increasing the paper density, and is satisfactory in optical properties such as opaqueness and whiteness.

Description

Holding ^ g

The present invention relates to a bulky paper containing a specific polyacrylamide.

In addition, the present invention relates to a bulky paper in which the density of the paper is improved without increasing the tension of the boat (interlayer boat, etc.), and the opacity and whiteness are high. Tall.

In recent years, the amount of pulp has been reduced due to the increase in fiber reinforced M and the reduction of difficulties in paper, and the bulk of paper has been increasing in crane m «yorin.

Means for increasing the bulk of the paper include lowering the pressing pressure in the papermaking press process, not using the force renderer that is used to apply 喊 to the shrimp surface, or using low pressure. . However, there is a problem that the ^ ftt is reduced and the suitability is poor. Also, a method using silica-free or trace-free silicate having a volume of J * M0.3 gZm1 or less as a 麟 Lin (JP-A-10-226982) is specified as Bukuro J, a chemical that reduces the density of paper. (WO98 / 03730- ^ ¾) using the alcohol and / or its polyoxyalkylene binding force (WO98 / 03730- ^ ¾), also using esterification of decorative alcohol and fatty acid ^! As a bulking agent; 200CH34691), a method of using a cross-linked pulp (Japanese Patent Laid-Open No. 4-185792 Bule, Marceli b

(Japanese Unexamined Patent Publication No. Hei 7-189168 ^^ Chrysanthemum and Heio) (Japanese Unexamined Patent Publication No. 3-269199), a method of shaping an object between pulp fibers (Japanese Unexamined Patent Publication No. 3-128895 S), Utilizing foaming particles that produce voids (Japanese Patent Laid-Open No. 5-230798, etc.). 1 · Life is big, which can cause problems.

As a means to improve encouragement, the ability to use each language is considered. Currently, polyacrylamide is widely used as a general recommended enhancer. However, although the movement of using bulky paper with 鹏増翻 is improved, Some have an opacity and white color, and that ¾S ^ is necessary. Therefore, the present invention aims to improve the recommendation and to provide a bulky paper with good luminosity. Disclosure of the invention

The inventors of the present invention have clarified the combination of the bulky paper with each of the 意 ¾ J J 結果重ね鉱 J 結果結果結果結果結果結果結果結果結果結果It was found that «^ -based Yokosuke Masubow Steel, which is used for both amphoteric purposes, was used to increase the density and further reduce the opacity, especially the optical properties. Relative binding, which is a pseudo-tag of the difficult binding of paper, is measured. The relative binding of paper containing »shows a large increase in the value compared to non-combined paper and age. When the relative ages of the bulky paper and the normal density paper, for example, the bulky paper made with fiber, such as the rubble iJ, and the rubble, the rubble J, and the paper, the relative age of It can be seen that the value of the bulky paper is greatly reduced as compared to that of the non-blended paper; It is considered that SiJ is likely to have a bad effect on the age, density and opacity when used. '

On the other hand, polyacrylamide 系 Masuyumi Zeni ij increases the density and impairs bulkiness, while the density increases l¾rf and improves the bulkiness, and it does not obscure light properties. It is understood that there is something Co

The polyacrylamide used as Ususuke Masu U has the following differences depending on the shape, such as ^ ^, the amount and amount of anion found in the carboxyl group, and the amount of the quaternary ammonium cation group.向上量カチオンとに向上向上向上向上向上向上向上向上向上向上向上向上向上向上向上向上向上向上Emits.

The present inventors have found that the density of bulky paper is improved, and that the light intensity is smaller than that of polyacrylamide. Polyacrylamide, which has a small amount of anion and a small amount of cations, is relatively It is presumed that the amount of amide groups that develop bow plating with hydrogen increases, and the plating increases, so that the paper strength can be improved efficiently and the light generation can be improved in density. Also, unlike OH, it gives to the relative bond of polyatarylamide ®! ^ Is small but has high density and high bulk, improves the quality of light, and improves the light ["Polyacrylamide which does not degrade life" is not blended with the relative binding fiber of the bulky paper containing it. It is known that the polyacrylamide is at least 1.2 times or less the bulk of the bulky paper, and Co is the best mode for carrying out the invention.

Hereinafter, the invention will be described in detail.

The polyacrylamide used in the present invention has, in the same molecule, an anion formed on the carboxyl group and a cation formed on the cation group of the quaternary ammonium or tertiary ammonium in the same molecule. Sf * is 2.0 m / g or less, and «» at pH 12 is 2.0 m / g or less; ^ T polyacrylamide. At each pH, the difference between the amount of cation '14S active at that pH and the amount of anion' 14S is shown.At pH 2, the activity of force cation is established. It shows a positive potential and a negative potential at pH12 because the anion's awakening is balanced.

The polyacrylamide used in the present invention is obtained by copolymerizing at least an acrylamide monomer, a cationic monomer or an anionic monomer.

As the acrylamide monomer I as a raw material of the polyacrylamide of the present invention, acrylamide or methacrylamide is the most preferred. Other examples include N-ethyl acryloleamide, N-N-dimethinorea linoleamide, N-isopropylacrylamide, diacetone acrylamide, etc. 1¾Χ can be used together with 2¾¾.

Examples of the cationic monomer include Ν, Ν-dimethylaminoethyl (meth) acrylate, Ν, Ν-getylaminoethyl (meth) acrylate, Ν, Ν-dimethylaminopropyl (meth) acrylate, Ν, Ν —Jetylaminopropyl (meth) acrylate, Ν, Ν-dimethylaminopropyl (meth) acrylamide, Ν, Ν—Jetylaminop Mouth pill (meth) acrylamide, arylamine, diarylamine ^ tertiary amine monomer or their «,«,, or, or tertiary amine monomer, can be converted to methyl chloride, chlorobenzene, dimethylene / resulfate And quaternary ammonium monomers quaternized with SiS with epiclo / rehydrin. These cationic monomers can be used together by the warrior ^ ffl.

Examples of the anionic monomer include monomers having a carboxyl group such as acrylic acid, methacrylo! ^, Monocarboxylic acid of crotone ^^, maleic acid, fumano, and itaconic acid.

The citracon ^ is a dicarboxylic acid of mucon ^^. These anionic monomers can be used in combination of two or more of ^ X.

In addition, as nonionic monomers, alkyl esters of f-anionic monomers (1 to 8 carbon atoms in the alkyl group), acrylonitrile, styrene chains, vinylinole, and methyl vinyl ether are used in combination of two or more. Let's do it.

Further, as cross-linking 14 monomers, di (meth) atalylates such as ethylene glycol di (meth) acrylate, jeti-lendly alcohol di (meth) acrylate, and triethylene glycol di (meth) acrylate, methylene bis (meth) acrylamide, Ethylene bis

Bis (meth) acrylamides such as (meth) acrylamide, hexamethylenebis (meth) acrylamide, etc., dibutyl ester such as dibiel adipate and vinyl sebacate, arylmethacrylate, diarylamine, diaryldimethylammonium , Diarylphthalein, etc., divinyl binno! ^ Nomers, 1,3,5-triatalyloylhexahydro-1S-triazine or triallylisocyanurate, etc. 3 ^ t. ^ Nomer. These raw monomers can be used in combination of two or more kinds of WlX.

The polyacrylamide of the present invention has a pH at pH 2 of not more than 2.Om equivalent g and a pH at pH 12 of not more than 2.Om equivalent / g. m / ft g or less, and βί¾ at pH12 is 1.8 m / 4 / g or less. S Desirable In addition, the relative age of the bulky paper containing polyatarylamide should not be used. It is less than 1.2 times the relative age S¾ of bulky paper.

The average molecular weight of the polyacrylnoleamide of the present invention is preferably 2,000,000 to 4,000,000. In addition, power ranged from ¾2.5 million to 3.5 million.

In order to incorporate the polyacrylamide of the present invention into paper, it is preferable to exfoliate the pulp in a range of 0.0 1-3. 0≤ *% per pal: 7%, preferably 0.05%. -1. 5≤ *% strength Especially preferred Leo Akiramoto's polyacrylamide-blended paper is used to reduce the press pressure in the paper-making process! Pressing the temple gives ⁵ pmt raw to his surface For example, a bulky paper which is not subjected to the force rendering performed or performed at a low temperature may be used.

In addition, it can be obtained by adding silicon dioxide and thorium to sulfuric acid, and it can be obtained by adding silica and sodium silicate to other sodium chloride at the same time as other sodium chloride, such as ^ τΚ Luminous aluminum silicate, sodium calcium silicate, calcium silicate or calcium silicate-free silicates having a bulk specific gravity of 0.3 gZm 1 or less are used.

Furthermore, fatty acid polyamide polyamine ィ ¾ ¾ ^ Ethylene oxide adduct of stearyl alcohol, propylene oxide adduct of stearyl alcohol, ethylene oxide adduct of decyl alcohol, fine alcohols such as pentaerythritol / restearate or stearin ^ glyceride. Esterification of fatty acid and fatty acid A chemical that lowers the density of the material.

In addition, dimethyl pulp is used for dimethyl pulp which is used for dimethylol ethylene urine, dimethylol dihydroxy ethylene urea, ethylene glycol / regisglycidyl ether, and dihydroxy ethylene urine, which has ¾ ^ する which is related to the hydroxyl group of cellulose. It is bulky paper using Marcelui / Reb, which is processed by treating the pulp with strong water at night. In addition, if β »| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^) With 発泡 I ^^^^^^^^^^^^^^^^^^^^^^^^^ + + + ^ ^ ^ ^ ^ + ^ ^ + + I + I + I + I + I + I + I + I + I + I + I + I ~ I ~ I ~ I ~ I ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ $ $

The bulky paper of the present invention is fine printing paper, medium quality printing paper such as fiber printing paper such as printing paper, art paper, and cast coat is high quality coated paper, PPC paper, ink-jet linguistic paper, laser printer paper, It can be used in the form of paper such as foam paper, paper, and IKXttffi paper. ' Difficult side

Examples of H are shown below, and this effort will be explained more fully. However, they are not limited to these.

Note that ⁰ / in the example. Indicates s *% in all cases.

For rilamide, pH at pH2 and pH12 was measured by the following method

Show the results; ^ 1 ".

®®f * at pH2

Add deionized water to polyacrylamide to make iSO.5 g / 1, and then add H2 to the H2 at night; charge it for 5 minutes. After CS for 5 minutes, stand up and measure [Model PCD03]

(Polyvinyl potassium (PVSK) is titrated with Mutek

The voltage 3 * at pH 2 was determined from the following equation.

¾t * (m equivalent ft / g) = VXC / W

(V in the formula is the titer of PVSK (ml), C is (mo 1/1) of PVSK, and W is sample / V * (g))

• Electricity at pH12

Deionized water was added to the polyacrylic § bromide and 5 g / 1, was纖Yuzuru Mr ^ 5 min _P H12 added hydroxide Natoriumu water赚,趨置D ^ ode 1 PCD03 measuring particle surface] (Mu The titration was carried out using Teknettsu using polydiaryldimethylammonium chloride (p DADMAC).

¾f における 4 at pH 12 was determined from the following equation.

(m equivalent A / g) = VXC / W

(V in the formula is the titer of p DADMAC (ml), C is S of p DADMAC (mo \ / 1), and Sampno (g).) table 1

The relative ^ of polyacrylamide is calculated from the following (Equation 1) (Reference: Philip Luner et. Al, TAPPI, 44 (6) 409 (1961)): ^

Table 2 shows the results; ^ ~ ₀

Relative binding fiber = (S ₀ -Sx) ZS. (Equation 1)

(The specific scattering coefficient of the composite sheet 1 mm from the S 0 angle / reb in the equation, S X indicates the specific extinction coefficient of the sample)

〇 Measurement of S ₀

Not叩角Army LBKP (¾ik degree CS F660m 1) to the pulse of aluminum sulfate: l6 | road amount per 0.9%, 0.1% per Parufu color ¾M the polyacrylamide (However, Fuji of age Parufu ¹ «S amount per 0 3%), weigh this pulp slurry so that the sheet basis weight after ¾ ^ is 70 g / m ² , and use a round TAPPI with a 150 mesh wire (にて 200 cm ² ). Abstract Next, press J¾foK at 1.25 kgf / cm ² for 5 minutes using a press machine, and make a paper with a small amount of paper under the conditions of 110 ° C and 60 seconds. the 1.25 kgf / cm ² for 5 minutes, further 4.18kg f / cm ² between the family Sukunaki sheet 2 minutes,-out rarely were 2 min at 4.18kg f / cm ² for 5 minutes further 4.18kg f / cm ² ! ft, 20. Ok g ί Zcm ² for 5 minutes, further 20.0Kgf ZCM ² in hospital and two minutes Sukunaki paper, SeiTsuge also handsheets changing the press cake like and c

After applying these papers at 23 ° C for 1 day with 50% key rice cake, the specific scattering coefficient and S¾f length were measured.

Create an approximation curve by plotting the values of 比 and ¾ length on a graph, then ^? ¾ (The ratio at which the f length becomes zero ¾The value of the SL coefficient is

〇Sx measurement

叩角LBKP (¾ft «CS F435m 1) to pulse the sulfuric acid band:» ¾ amount per 0.9 ^0'm polyacrylamide Pal: ft¾¾ amount per 0.1% (however, 0.3% the age of Fuji Pal 7% flame amount per) work The pulp slurry is weighed so that the sheet basis weight after 氏 ^ becomes 70 g / m ^2, and the pulp slurry is wrapped with a 150 mesh wire (®¾200cm ² ) with round TAP PI.

Next, press ¾ 418 kgf Z cm ² for 5 minutes and press 4.18 kg f / cm ² minutes with a press machine. Create paper †

After the obtained paper was conditioned for 1 day at 23 ° C and 50% boat speed, the J m disturbance coefficient was measured and this was designated as Sx.

Paper strength bow steel Relative binding S to Blank ratio phase ¾fg composite ® 合

PAM— 01 0.189 1.07

PAM— 02 0.191 1.09

PAM— 03 0.183 1.04

PAM— 04 0.185 1.05

PAM— 05 0.183 1.04

PAM— 06 0.190 1.08

PAM— 07 0.198 1.13

PAM— 08 0221 1.26

PAM— 09 0219 124

PAM— 10 0228 1.30

PAM-11 0231 1.31

Wisteria—01 0255 1.46

Oh-02 0271 1.54

None 0.176

Hidden example 1 7 J: t »i | l ~ 4]

LBKP (age CS F385m 1) with sulfuric acid band in parf color 0.9 0.9% per M4, polyacrylamide shown in Table 3 as pal:% 0.3% per S4, ± thixorex 17 as Rin (10 weight per unit weight in lary column) % Co

Weighed as the basis weight of the sheet after one to pulp slurry is 60 gZm ^2, FREE缺a 150-mesh wire at TAP P 1¾1 opening machine (®¾200cm ²⁾ Next, with 418k g fZcm ² 5 minutes And press for 2 minutes at 4.18 kg f / cm ² for 5 minutes.

Create tension paper for 1 hour at 0 ° C

[Job 5 6]

LBKP (ί ^ CS F385m 1) with a modified band of Pal: 0.9% per ¾¾fi *, 11% shown in Table 3 as 1.0% per balm mm * ^] So that iom *% per amount. to

Measure this parcel slurry so that the basis weight of the sheet of the worker is 60 g / m ^2, and use a 150 mesh wire (® ²⁰⁰ cm ² ) g ^ in the TAP PI job and then 418 kg f / cm ² 5 minutes, plus 418 _§ £ _ /. 111 ² Press for 2 minutes with a press machine at 50 ° C for 1 hour to make special paper and add polyacrylamide to the paper. Create a rare paper in the same manner as above: ^ Difficult example 1 ~ 7 R ^ i 1 ~ 7 family paper was humidified for 1 day at 23 ° C, boat 50% miscellaneous, then the density, White ^ Measure the transparency by the following method

Table 3 shows the results.

〇 Density: JISP 8118

〇 Length: JISP 8113

〇Hunter Haku 继: Working for JIS P8123

〇Hunter opacity: JISP 8138 was applied.

Table 3

M¾Examples 8-14, 1; 赚 U8 ~ l l]

In LBKP (it * degree CS F435m 1), band was 0.9% per pallet *, alkyl ketene dimer → 0.2% per pallet door, Table 4 %, ¾ ^ KB calcium carbonate as «weight per 30 wt ⁰ do bulk as DOO - 110 was added (Kao Corporation) so as to have a 0.6% per Pal color ^

Weigh this pulp slurry so that the basis weight of the sheet after carrying is 80 gZm ² , apply it with a 150 mesh wire (ffi ^ OOcm ² ) at TAP P Ιί ^ ^ ^ Next, 4.18 kgf / cm ² for 5 minutes, and 4.18 kg f / cm ² for 2 minutes with a press machine, and dry with a cow using a cow at 110 ° C for 60 seconds to make a little paper.

2 to 13] LBKP (degree CSF435ml) 0.9% per sulphate band per pal, 0.2% per pal of alkyl ketene dimer as sizing agent, ^ 11¾ in Table 4, 0.3% per パル, ± 30% per ± calcium carbonate as a static funnel %, Pokaku IJ KB-110 (¾ΞΕ Co., Ltd. m: Pal: «Suggest to be 0.6% per fi4 ^

Measure this parcel slurry so that the basis weight of the sheet after Mr. になる ^ is 80 g / 2Ω ² , and carry it with a TAP Ρ sculpture using a 150 mesh wire (ffi¾200 cm ² ) and then 4.18 kgf / Press with a press machine for 5 minutes at cm ² for 5 minutes at 4.18 kg f / cm ² , and make a paper using a fiber dryer with a cylinder dryer at 110 ° C for 60 seconds at 60 ° C.

D WJ14]

Polyacrylamide ^] tl な »» »» 同様同様例例同様同様同様同様例例例同様同様同様雞雞雞雞雞雞雞雞 8 雞 8 雞 8 8 8 8 8 8 8. C. After tanning with 继 50% rice cake for 1 day, the density, enema, whiteness and opacity were measured as described above.

The results are shown in Table 4ί; ΐ ^ Τ.

Table 4

Ugly example 15 21 1; 赚! Jl 5-18]

LBKP (i K degree C S F385m 1) band was 0.9% per pal color Idt amount, Table 5 polyacrylamide was 0.3% per pal amount, and polished IJ was KB-08W (Kao Corporation

) Add m so that it becomes ι · ο% per amount of par ^ ima ^

This pulp slurry is weighed so that the basis weight of the sheet after the pulp is 60 gZm ^2, and it is wrapped with a 150 mesh wire (^ 200 cm ² ) in a round TAPP job, and then it is weighed at 4.18 kgf / cm ² Press for 5 minutes, then press for 4. minutes at 4.18 kgf Z cm ² for 2 minutes, and dry with a cylinder dryer at 110 ° C for 60 seconds to make handmade paper: ^

[赚 19-20]

LBKP (i ^ K degree CS F385m 1) with band at 0.9% per parf 量 S amount, Table 51 11 »pulp: 1.0% per fe¾S4, KB- 08W (3E, Inc.)

This pulp slurry is weighed so that the basis weight of the sheet after IS is 60 g / m ² ,

And携氏with TAP PI Yoridokoro纖at 150 mesh wire (®¾200cm ²⁾ Next, press fek at .18k gf / cm ² for 5 minutes, further 418kg f / "cm ² in 2 minutes press 1 Handmade paper was prepared by drying with a cylinder drier at 10 ° C for 60 seconds at 60 ° C.

[1: 21]

For polyacrylamide ^!] Sashimi, rare paper was prepared in the same manner as in Example 15, and males 15-21 and 23 for return papers 15-21. C, key 50%, after humidity control for 1 day, measure density, »length, white" transparency as described above; ^

The results are shown in Table 5 ^ Τ.

Table 5

Example 22 28 J;! 122 25]

Needles »The pulp was immersed in a 5% sodium hydroxide descendant at 20 ° C for 30 minutes, and neutralized with sulfuric acid K solution. Dimethylol dihydroxyethylene urea is added to the mixture, and the mixture is heated at 70 ° C for 2 hours. 10 parts by weight of the obtained crosslinked pulp (¾ΙτΚ degree CS F420m 1) and 90 parts of LBK P (it * degree CSF435 ml) 90S * part Pulping a sulfate band into a mixed pulp consisting of:

0.9% per amount In Table 6, ^ T polyacrylanolamide was added at 0.3% per pal.

This pulp slurry was weighed so that the basis weight of the sheet after carrying was 60 g / m ^{2, and} was wrapped with a round TAP P 1 sculpture using a 150 mesh wire (ffi 型²⁰⁰ cm ² ). Then, pressed Agata at 4.18kgf / cm ² for 5 minutes, further 4.18kg ί / cm ² for 2 minutes press, 5 I made tension paper at 0 ° C for 1 hour

[]:,!] 26 ~ 27]

Needle pulp is 脑 5o / ₀ sodium hydroxide water. C, after immersion for 30 minutes, neutralize by adding a solution, add dimethylol dihydroxyethylene urea to this, add water at 70 ° C for 2 hours,

Obtained suitable panorep

S F420m 1) lOfiS part and LBKP (ii * degree CSF435m 1) Male band on mixed pulp consisting of 90S * part: 0.9% per% ¾fi *, Table 6: 1.0% per 7 colors of pulp I'm sorry ^

Weighed basis weight of a sheet of your «after the pulp slurry so that the 60g Zm ^2, and Mr. a 150-mesh wire (¾200cm ²⁾ by mosquitoes邀TAP P 1躪Then, in 4.18kgf / cm ² Press for 5 minutes at 4.18 kg f / cm ² for 2 minutes with a press machine, then strain at 50 ° C for 1 hour »to make paper

0: 赚 [J28]

The polyatarylamide was not added, and ^ was the same as in Example 22 to prepare a small amount of paper. Difficult cases 22-28 and 23 were rare papers in Examples 22-28. C, after humidity control with 50% key mochi for 1 day, density, length, white and opacity were measured as described above

Results in Table 6 ^ 1 ".

Table 6

Availability of

As shown in Tables 3 to 6, at pH 2 is 2.0 m equivalents or less and at pH 12 is 2. Om equivalents / g or less ^ Polyacrylamide was contained. Larger than polyacrylamide or 有し ½ 有し:]: Compared with tUU paper, without increasing the density, the bin length is improved, the opacity and whiteness are high, and the light I "贿

In addition, the results show that polyacrylamide (PAM-01 to PAM-07), which has a small increase in the relative bond content to the non-increased steel (Blank), has an increased relative bond fiber. Large amounts of polyacrylamide (PAM—08 to PAM—011), ί¾, It has also been found that the desired effects of the present invention can be obtained in comparison with powders 0 1 to 0— 0 2).

Claims

The scope of the claims

1. The value at pH 2 is not more than 2.0 mg / g and the value at pH12 2. * is 2. Om / g or less, and the bulk is defined by mixing ^ 1 to polyatarylamide!

2. The bulk of the blend of the polyacrylamide of claim 1 and non-silicone power or non-^^ silicate with a bulk density of 0.3 g / ml or less

3. The combination of the polyacrylamide of claim 1 and a bulking agent composed of a fatty acid polyamide compound or a bulking agent composed of an ester compound of a ^ I alcohol and a fatty acid is used as a town.

4. The bulkiness of claim 1 in which the fiber polyacrylamide is mixed with mercerized pulp or crosslinked pulp.

5. The method according to any one of claims 1 to 4, wherein the relative bonding area of the bulky paper containing polyacrylamide is 1.2 times or less of the relative bonding of the bulky paper without blending polyacrylamide. Fiber bulkiness' low