JP2001081687A - Paper quality improving agent for paper making - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner addition type paper quality-improving agent that can make paper sheets having increased standard bulkiness, whiteness, opacity by selecting the compounds that have the paper quality-improving effect higher than specific values in the syneresis, bulkiness and optical properties. SOLUTION: A compound that has two or more of the paper quality- improving effects that satisfies the following requires: a syneresis degree of >=4%, according to the formula: the syneresis degree in %=(α0-α) (α is a water content in % of the wet paper after 5 pts.wt. of a compound as a paper quality-improving agent is added to 100 pts.wt. of pulp; and α0 is the water content in %, when the compound is not added); the increase in the standard bulkiness is >=0.02 g/cm3; the increase in the standard whiteness is >=0.5 point; and the increase in the standard opacity is >=0.5 point are selected from compounds, for example, organosiloxane, glycerol ether, amide, amine (and acid salt, thereof), quaternary ammonium salt, imidazole and esters from polyhydric alcohol and fatty acid (alkylene oxide adducts) to produce the objective paper quality-improving agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a papermaking quality improving agent which can improve optical properties such as bulk, whiteness and opacity of a sheet obtained by making a pulp raw material.

[0002]

2. Description of the Related Art From the viewpoint of protection of the global environment, it is required to reduce the amount of pulp used. As a result, it is required to reduce the weight of paper and increase the amount of recycled pulp. However, the paper obtained by simply reducing the amount of pulp in the paper has a low opacity due to the thinning of the paper, resulting in poor quality. Also,
In the case of weight reduction in which the amount of pulp in paper is reduced, paper having a rigidity proportional to the cube of the thickness, such as paperboard, has an undesirable decrease in rigidity. On the other hand, when the mixing ratio of the used paper pulp is increased, the whiteness decreases due to the residual ink in the used paper pulp, and the pulp itself becomes thin in the recycling process, so that the paper thickness decreases and the opacity decreases. Therefore, when the amount of pulp in the paper is reduced and the mixing ratio of the waste paper pulp is increased, the opacity and whiteness of the obtained paper are further reduced. In addition, when the whiteness of waste paper pulp that causes a decrease in whiteness is increased by deinking or bleaching, the opacity of the obtained paper is further reduced, which is not preferable.

[0003] For the purpose of preventing a reduction in thickness due to weight reduction, various methods for improving bulk have been attempted in the past. For example, a manufacturing method in which the press pressure is reduced has a problem that smoothness is reduced and printability is deteriorated. In addition, a crosslinked pulp is used (for example, JP-A-4-185792), mixed with synthetic fibers (for example, JP-A-3-269199), and a filler such as an inorganic substance is filled between pulp fibers (for example, JP-A-3-24895). ), And a method of providing voids (Japanese Patent Application Laid-Open No. 5-230798), but the pulp cannot be recycled or the smoothness of the paper is impaired. As a paper bulking agent, a specific alcohol and / or a polyoxyalkylene adduct thereof (W098 / 03730) is known. Furthermore, the performance of the fatty acid polyamide polyamine type commercially available as a bulking agent is not sufficient.

On the other hand, in order to improve opacity and whiteness, a method of adding a large amount (for example, 5 to 20% by weight) of an inorganic filler such as calcium carbonate, kaolin or white carbon has been practiced in the art. . However, simply adding a large amount of an inorganic filler significantly increases the weight of the paper. Even if the amount of pulp is reduced and an inorganic filler is added, the weight of the paper cannot be reduced. Particularly, when an inorganic filler is added to waste paper pulp, a large amount is required, and it is increasingly difficult to reduce the weight of paper.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems associated with the reduction in weight of paper and the increase in the amount of waste paper pulp. Specifically, by modifying the pulp surface, An object of the present invention is to provide a papermaking paper quality improver that achieves at least two of improvement in bulk, whiteness and opacity.

[0006]

The present invention provides a compound having a water separation of 4% or more as defined below.
The present invention provides a papermaking paper quality improver which comprises any two or more of the compounds (i) to (iii) and has a paper quality improving effect and is internally added before the papermaking process. (i) Standard bulk improvement of 0.02 g / cm ³ or more (ii) Standard whiteness improvement of 0.5 point or more (iii) Standard opacity improvement of 0.5 point or more Water separation (%) = (α ₀ −α) / Α ₀ × 100 α: Moisture content of a wet sheet obtained by adding 5 parts by weight of a compound serving as a papermaking paper quality improver to 100 parts by weight of pulp α ₀ : A compound serving as a papermaking paper quality improver Moisture content of wet sheet obtained by making paper without adding to pulp

The method for measuring the degree of water separation, the degree of improvement in standard bulk, the degree of improvement in standard whiteness and the degree of improvement in standard opacity in the present invention will be described in detail.

[Measurement Method of Water Separation Degree] (A) Pulp used Hunter whiteness of handmade pulp sheet prepared by the method for preparing handsheet paper for pulp test of JIS P 8209 (JIS P 812)
Use bleached bleached pulp derived from beech (hereinafter referred to as LBKP) whose 3) is 80 ± 5%. (B) Measurement of degree of water separation LBKP was disintegrated in a beater at 25 ± 3 ° C. with a beater and beaten to 460 ± 10 ml with Canadian standard freeness (JIS P 8121) to give an LBKP slurry with a pulp concentration of 1.0% by weight. Get. The pulp slurry was weighed so that the basis weight of the LBKP of the sheet after papermaking was 80 ± 2 g / m ² , and the pH was adjusted to 4.5 with aluminum sulfate. Of ethanol solution was added to 5 parts by weight (pure content) with respect to 100 parts by weight of pulp, and the mixture was added to a round tappi paper machine.
Paper is made with a 150 mesh wire (area 200 cm ² ) to obtain a wet sheet. ^Two filter papers (diameter 185 mm) having a basis weight of 320 ± 20 g / m ² are superimposed on the wet sheet, and a coach plate is further superimposed thereon for coaching, and then the wet sheet is taken out. Next, the wet sheet is sandwiched between the two filter papers,
Press at 340 ± 10 kPa for 5 minutes. After pressing, the weight w (g) of the wet sheet is immediately weighed. Next, 105 ± 3 ℃, 6
After drying for 0 minutes, the weight W _d (g) of the obtained dried sheet is weighed. W obtained above, the W _d, moisture content α by (1)
(%). α (%) = (W−W _d ) / W × 100 (1) Also, a sheet was prepared in the same manner without adding a compound to be used as a papermaking paper quality improver, and the water content determined in the same manner was α ₀ . I do. From the water content α and α ₀ obtained above, the degree of water separation is obtained from the following equation (2). Degree of water separation (%) = (α ₀ −α) / α ₀ × 100 (2)

[Measurement Method of Standard Bulk Improvement] LBKP is defibrated with a beater at 25 ± 3 ° C. and beaten to 460 ± 10 ml at a Canadian standard freeness (JIS P 8121) to give a pulp concentration of 1.0. A weight percent LBKP slurry is obtained. After weighing this pulp slurry so that the basis weight of the LBKP of the sheet after papermaking becomes 80 ± 0.5 g / m ² ,
After adjusting the pH to 4.5 with aluminum sulfate, 0.5% by weight (pure amount) of a 1.0% by weight ethanol solution of a papermaking paper quality improver is added to 100% by weight of pulp, and 150 mesh by a round tappi paper machine. Paper is made with a wire (area of 200 cm ² ) to obtain a wet sheet. ^Two filter papers (diameter 185 mm) having a basis weight of 320 ± 20 g / m ² are superimposed on the wet sheet, and a coach plate is further superimposed thereon for coaching, and then the wet sheet is taken out. Next, the wet sheet is sandwiched between the two filter papers, and pressed at a pressure of 340 ± 10 kPa for 5 minutes. After pressing, only the sheet is dried at 105 ± 3 ° C. for 2 minutes using a mirror-surface dryer. The dried sheet is conditioned for 5 hours at 20 ± 1 ° C. and 65 ± 2% humidity. The weight of the conditioned sheet is measured and the following formula (3) is used.
To determine the basis weight (g / m ² ). Basis weight (g / m ² ) = sheet weight / 0.02 (3) Next, the thickness of the conditioned sheet was measured at 10 places using a paper micrometer at a pressure of 54 ± 5 kPa, and the average value obtained was obtained. Is the thickness (mm). Tension d (g / cm ³ ) is determined from the basis weight and thickness obtained above by the following equation (4). d = (basis weight) / (thickness) × 0.001 (4) Also, a sheet is prepared in the same manner without adding a compound to be a papermaking paper quality improver, and the tension obtained in the same manner is defined as d ₀ . From the tensions d and d ₀ determined above, the standard bulk improvement is determined by the following equation (5). Standard bulk improvement (g / cm ³ ) = d ₀ -d (5)

[Measurement Method of Standard Whiteness Improvement] The same as the measurement method of standard bulk improvement. The conditioned sheet is measured for whiteness B according to JIS P 8123, Hunter whiteness. Also, without the addition of compounds to be the paper quality improver for papermaking Similarly the sheet was prepared and whiteness obtained in the same manner and B _0. Whiteness B obtained above, the B _0, obtains the standard whiteness enhancer of the following equation (6). Standard degree of whiteness improvement (points) = BB ₀ (6)

[Measurement Method of Standard Opacity Improvement] The same as the measurement method of standard bulk improvement. The opacity P of the conditioned sheet is measured according to JIS P 8138A. In addition, a sheet is prepared in the same manner without adding a compound serving as a papermaking paper quality improver, and the opacity obtained in the same manner is defined as P ₀ . From the opacity P and P ₀ obtained above, the standard opacity improvement is obtained by the following equation (7). Standard opacity degree of improvement _{(point) = P-P 0 (7} )

As described above, 1.0% by weight is obtained by a predetermined method.
By preparing 5% by weight of pulp with respect to pulp, and measuring the degree of syneresis by adding 5% by weight of pulp, and measuring the degree of improvement of standard bulk, standard whiteness, and standard opacity by adding 0.5% by weight of pulp. The papermaking paper quality improver of the present invention is easily specified.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A compound having a water separation of 4% or more as defined in the present invention, when added to a pulp slurry and fixed to the pulp, renders the pulp surface hydrophobic, so that the interfacial tension between the pulp and the aqueous solution increases. However, it is thought that the pulp sheet having increased whiteness and opacity can be obtained by increasing voids between the pulp during papermaking and obtaining a bulky pulp sheet and increasing optically reflectance. . Further, only a part of the pulp surface is hydrophobized as in the case of adding a small amount of the compound, the voids between the pulp are not increased, and even when the expression of bulkiness is small, the number of hydrogen bonds between the pulp is reduced. It is thought that the pulp surface area increases, the optical reflectance increases, and the whiteness and opacity are improved. Note that the whiteness is calculated from the lightness (L value) and the b value, and the greater the L value, the greater the b value. The whiteness improvement effect according to the present invention is considered to be caused by an increase in the L value. . Heretofore, the relationship between the hydrophobicity of the pulp surface and the bulkiness and optical properties has not been known, but the present inventor has found that there is a correlation between the two. Furthermore, it has been found that when a compound having a water separation of 4% or more, preferably 5% or more as defined above is used, a pulp sheet having improved bulk, whiteness and opacity can be obtained even with a small amount of addition. In addition, pulp sheet is JIS P 00
The paper and paperboard described in 01 are collectively referred to.

The compound of the present invention having a water separation of 4% or more has a (i) standard bulk improvement of 0.02 g / cm ³ or more, preferably 0.025 g / cm ³ or more, more preferably 0.03 g / cm ³ or more, as defined in the present invention.
g / cm ³ or more, (ii) standard whiteness improvement of 0.5 point or more, preferably 0.7 point or more, more preferably 0.9 point or more, and (iii) standard opacity improvement of 0.5 point or more, preferably 0.7 point Above, more preferably
Compounds satisfying at least two of (i) to (iii) of 0.9 points or more, and more preferably satisfying three.

In the present invention, the compound having a water separation of 4% or more is preferably an organic compound having a hydrophilic group for adsorbing on the pulp surface and a hydrophobic group for hydrophobizing the pulp surface. , (B) glyceryl ether, (C) amide, (D) amine, (E) amine salt, (F) quaternary ammonium salt, (G) imidazole, (H) ester of polyhydric alcohol and fatty acid, and ( I) An ester of a polyhydric alcohol and a fatty acid, the average of which is 0 per mole of the ester.
It can be selected from the group consisting of alkylene oxide addition esters having an alkylene oxide group having 2 to 4 carbon atoms of more than 12 moles.

(A) The organosiloxane has a viscosity of 1 at 25 ° C.
0 to 1,000,000 mPa · s methylpolysiloxane, polyoxyethylene methylpolysiloxane copolymer having an HLB of 1 to 14 by the Griffin method, poly (oxyethyleneoxypropylene) methylpolysiloxane copolymer having an HLB of 1 to 14 And the like.

The glyceryl ether (B) includes a compound represented by the following general formula (a).

[0018]

Embedded image

Wherein R ₁ is an alkyl group having 8 to 35 carbon atoms;
It is an alkenyl group or a β-hydroxyalkyl group. Examples of the (C) amide, (D) amine, (E) amine salt, (F) quaternary ammonium salt, and (G) imidazole include compounds represented by the following general formulas (b) to (j). The amine salt includes both ionized and non-ionized ones.

[0020]

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[Wherein, Y ₁ and Y ₂ are the same or different and each represent a hydrogen atom, R ₄ or R ₆ C
O-,-(AO) _n -COR ₃ or-(AO) _n -H AO: alkylene oxide having 2 to 4 carbon atoms Y ₃ : hydrogen atom or -COR ₆

[0022]

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R ₁ : same as the above formula (a) R ₂ , R ₃ , R ₆ , R ₉ : alkyl group, alkenyl group or β-hydroxyalkyl group having 7 to 35 carbon atoms R ₄ , R ₅ : hydrogen Atom or alkyl group having 1 to 3 carbon atoms R ₇ , R ₈ : alkyl group having 1 to 3 carbon atoms R ₁₀ : hydrogen atom or R ₉ n: average number of moles 1 to 20 X ⁻ : anion]

The polyhydric alcohols constituting the compounds (H) and (I) have a total carbon number of 2 which may contain an ether group.
-24 to 2-14 alcohols are preferred, 2 to 8 alcohols are more preferred, and 3 to 6 alcohols are particularly preferred. As the dihydric alcohol, those having a total carbon number of 2 to 10 which may contain an ether group, for example, propylene glycol, dipropylene glycol, butylene glycol,
Examples thereof include dibutylene glycol, ethylene glycol, diethylene glycol, and polyethylene glycol. Examples of the trivalent or higher alcohol include alcohols having a total carbon number of 3 to 24 which may have an ether group and having a total number of hydroxyl groups / total carbon number in one molecule of 0.4 to 1, for example, glycerin, polyglycol, and the like. Glycerin (average degree of condensation 2 to 5), pentaerythritol, dipentaerythritol, arabitol, sorbitol, stachyose, erythritol,
Arabic, mannitol, glucose, sucrose and the like. More preferably, ethylene glycol, diethylene glycol, propylene glycol, or an alcohol having a total carbon number of 3 to 12 which may have an ether group is a trivalent or higher valent compound in which the number of hydroxyl groups in one molecule / the total number of carbon atoms is 0.5 to 1. Alcohol. Particularly preferred are glycerin, polyglycerin (average degree of condensation of 2 to 4) and pentaerythritol.

The fatty acids constituting these esters include fatty acids having 1 to 24 carbon atoms, preferably 10 to 22 carbon atoms, and may be any of saturated, unsaturated, straight chain and branched chain, and particularly straight chain. Chain fatty acids are preferred. More preferably, lauric acid, myristic acid, palmitic acid, stearic acid,
Behenic acid and oleic acid. Particularly, stearic acid is preferred.

These esters can be obtained by performing a known esterification reaction and alkylene oxide addition reaction. For example, an esterification catalyst may be added to a mixture of a fatty acid and a polyhydric alcohol if necessary, and the mixture may be reacted at 150 to 250 ° C. to obtain an ester. In addition, an alkylene oxide having 2 to 4 carbon atoms in the presence of an alkali catalyst or the like. Is added to obtain an alkylene oxide addition ester. Further, after adding an alkylene oxide to a fatty acid or a polyhydric alcohol, esterification may be performed. Furthermore, it may be obtained by only adding an alkylene oxide to a fatty acid.

The average degree of ester substitution of this ester is preferably such that 10 to 95 equivalent% of OH in the alcohol is substituted per mol of polyhydric alcohol, and particularly preferably 1 to 1 per mol of polyhydric alcohol. It has about 2 mol of ester groups.

When an alkylene oxide addition ester is used, the number of moles of AO added per mole of the ester is more than 0 mol and less than 12 mol on average, preferably 0.1 to 6 mol. In the case where a polyhydric alcohol that can be an AO group such as ethylene glycol is used,
Take into account the number of AO groups. The alkylene oxide is preferably ethylene oxide (hereinafter referred to as EO) or propylene oxide (hereinafter referred to as PO). These may be either EO or PO alone or a mixture of EO and PO. In the present invention, AO
It is particularly preferred to use esters of polyhydric alcohols and fatty acids that do not contain groups.

The papermaking paper quality improver of the present invention may be added as it is for a liquid product, but may be added for a solid product after pulverization or melting by heating or after dilution with water or the like. Also,
If necessary, a nonionic, anionic, cationic or amphoteric surfactant may be used as an emulsifier or dispersant for a papermaking paper quality improver. Preferably an anionic surfactant or a cationic surfactant surfactant,
More preferably, they are as follows. -Higher fatty acid salts such as sodium, potassium and ammonium salts of stearic acid, oleic acid, palmitic acid, myristic acid, lauric acid, rosin acid and tall oil fatty acids. -Higher alcohol sulfates such as sodium, potassium and ammonium salts of lauryl sulfate, myristyl sulfate, palmityl sulfate, stearyl sulfate and oleyl sulfate. Alkyl benzene sulfonates such as sodium straight chain dodecyl benzene sulfonate and sodium branched chain dodecyl benzene sulfonate; Sulfosuccinic acid diester salts, for example, di-2-ethylhexyl sulfosuccinate sodium salt, diisotridecyl sulfosuccinate sodium salt, dicyclohexyl sulfosuccinate sulfosuccinic acid, and the like. Naphthalene sulfonate-formaldehyde condensatePolycarboxylates For example, sodium, potassium, calcium and ammonium salts of polyacrylic acid, polymethacrylic acid and polymaleic acid, or acrylic acid, methacrylic acid,
Sodium salt, potassium salt, calcium salt, ammonium salt and the like of a copolymer comprising two or more selected from the group consisting of maleic acid and styrene. -Quaternary ammonium salts Hydrochlorides of lauryl trimethyl ammonium, cetyl trimethyl ammonium, stearyl trimethyl ammonium and distearyl dimethyl ammonium.

In this case, the ratio of the papermaking paper quality improving agent of the present invention to the surfactant is preferably 99.9 / 0.1 to 70/30 (weight ratio), preferably 99.9 / 0.1 to 70/30. 99.8
/0.2 to 80/20.

The papermaking paper quality improver of the present invention can be widely applied to pulp raw materials such as mechanical pulp such as thermomechanical pulp (TMP), virgin pulp such as chemical pulp such as LBKP, and waste paper pulp. When used paper pulp is blended, its blending amount is preferably at least 10% by weight, more preferably at least 30% by weight in the raw pulp.

The papermaking paper quality improver of the present invention is added before or during the papermaking process (internal addition). As the place of addition, before the papermaking process in which the diluted liquid of the pulp raw material is drained while traveling on the wire mesh to form a paper layer, a disintegrator or a beater such as a pulper or a refiner, a machine chest, a head box, or white water It may be added to a tank such as a tank, or a pipe connected to these facilities, but a place where it can be uniformly blended with the pulp raw material, such as a refiner, a machine chest, or a head box, is desirable. It is preferable that the papermaking paper quality improver of the present invention is added to the pulp raw material, then made as it is, and most of it remains in the pulp sheet.

At the time of paper making, a sizing agent, a filler, a retention improver, a drainage improver, a paper strength improver and the like may be added. In particular, in order for the papermaking paper quality improving agent of the present invention to exhibit its function, it is important to fix the pulp to the pulp, and for this purpose, it is preferable to add an agent that promotes fixing.
Examples of the agent for promoting fixing include aluminum sulfate, cationized starch, a compound having an acrylamide group, and polyethyleneimine. The addition amount of the fixing promoting agent is preferably 0.01 to 5 parts by weight based on 100 parts by weight of the pulp raw material.

[0034] The papermaking paper quality improver of the present invention is a pulp raw material.
0.01 to 5 parts by weight per 100 parts by weight, especially 0.1 to 2 parts
Addition of a small amount of parts by weight improves at least two of the optical properties such as bulkiness, whiteness and opacity.

The compound for improving the quality of papermaking paper of the present invention can be used as a bulkiness improver for papermaking, a whiteness improver for papermaking, and an opacity improver for papermaking.

The pulp sheet obtained by using the papermaking paper quality improver of the present invention has a bulkiness index of 0.02 g / cm ³ or more, preferably 0.03 g / c, as compared with the non-added sheet.
m ³ or more lower is preferable, whiteness 0.5 points or more, it is preferably preferably greater than 0.7 points,
The opacity is preferably higher than 0.5 point, more preferably higher than 0.7 point.

Further, the pulp sheet obtained by using the papermaking paper quality improver of the present invention is classified according to the item classification described in the Handbook of Paper and Pulp Technology (published by Japan Society of Paper and Pulp Technology, pp. 455-460, 1992). It is suitably used for paper such as newspaper winding paper, printing / information paper, packaging paper, etc., or paperboard.

[0038]

EXAMPLES In the examples, "parts" are parts by weight and "%" are% by weight unless otherwise specified.

[Papermaking paper quality improvers] Tables 1 to 6 show the compounds used as the papermaking paper quality improvers and their water separation, standard bulk improvement, standard whiteness improvement and standard opacity improvement. When measuring the degree of syneresis, filter paper No. 26 for production of Advantech Toyo Co., Ltd. (diameter 185 mm, basis weight 320 g / m ² )
Was used.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

[Table 4]

[0044]

[Table 5]

[0045]

[Table 6]

F-1: 4.5 g of pentaerythritol stearate (average degree of ester substitution: 45 equivalent%) and 0.5 g of sodium dodecyl sulfate were added to 95 g of hot water at 70 ° C.
After stirring and homogenizing, a dispersion of 5% of an effective component was prepared by being left at 25 ° C. for 1 hour.

F-2: 4.0 g of pentaerythritol stearate (average degree of ester substitution: 45 equivalent%) and 1.0 g of cetyltrimethylammonium hydrochloride were added to 95 g of 70 ° C. hot water.
A dispersion containing 5% of an effective component, which was added to the mixture, stirred and homogenized, and left standing at 25 ° C. for 1 hour.

[Pulp Raw Materials] As the pulp raw materials, used paper pulp and virgin pulp shown below were used. <Recovered paper pulp> Recovered paper pulp is 100 parts of raw paper recovered from the market (newspaper / flyer = 70/30%), 60 parts of hot water and 1 part of sodium hydroxide, 3 parts of sodium silicate, 30% hydrogen peroxide 3 parts of water, tallow / glycerin (1
/ 1 weight ratio) EOPO block adduct (average number of moles added = EO)
(70 mol, 10 mol of PO) was added, and a 1% deinked pulp slurry obtained by defibration, flotation treatment, washing with water and concentration adjustment was used. Canadian standard freeness (JIS P 8
121) was 220 mL.

<Virgin Pulp> Chemical pulp: LBKP (hardwood bleached pulp) was disintegrated and beaten at 25 ° C. with a beater to form a 1% LBKP slurry. Canadian standard freeness (JIS P 8
121) was 420 mL.・ Mechanical pulp: TMP (thermomechanical pulp) 90
A 1% TMP slurry obtained by disintegrating with warm water at ℃ was used. It has a Canadian standard freeness (JIS P 8121) of 10
It was 0 mL.

[Papermaking Method-1] Waste paper pulp slurry and LBKP pulp slurry were each weighed so that the basis weight of the pulp of the sheet after papermaking became 60 g / m ² , and the pH was adjusted to 4.5 with aluminum sulfate. Then, Tables 1-6
0.5 to 100 parts of pulp
Was added and the paper was made with an 80-mesh wire (area: 200 cm ² ) using a square tapping paper machine to obtain a sheet. The sheet after papermaking was pressed with a press at 3.5 kg / cm ² for 2 minutes, and dried at 105 ° C. for 1 minute using a mirror-surface dryer. The dried sheet was conditioned at 20 ° C. and a humidity of 65% for one day, and the tightness, whiteness and opacity of the paper were measured by the following methods. The measured values are the average of 10 measurements. The results are shown in Tables 7 and 8.

<Evaluation Items and Methods> Tension The grammage (g / m ² ) and the thickness (mm) of the conditioned sheet were measured, and the tension (g / cm ³ ) was determined by the following formula. . Tension = (basis weight) / (thickness) × 0.001 The smaller the tension, the higher the bulk, and the difference of 0.02 in the tension is sufficiently recognized as a significant difference.・ Whiteness According to JIS P 8123 Hunter whiteness. A 0.5 point difference in whiteness is well recognized as a significant difference.・ Opacity According to JIS P 8138A method. A difference of 0.5 points in opacity is well recognized as a significant difference.

[0052]

[Table 7]

[0053]

[Table 8]

[Papermaking method-2] Waste paper pulp slurry and LBKP pulp slurry were weighed so that the basis weight of the sheet after papermaking became 60 g / m ² , and then the above A-5 and F-
1, F-2 or E-1 papermaking paper quality improver per 100 parts of pulp
0.5 part was added, and the sheet was formed with an 80-mesh wire (area: 200 cm ² ) using a square tapping paper machine to obtain a sheet. The sheet after papermaking was pressed with a press at 3.5 kg / cm ² for 2 minutes, and dried at 105 ° C. for 1 minute using a mirror-surface dryer. The dried sheet was conditioned at 20 ° C. and a humidity of 65% for one day, and then the tightness, whiteness and opacity of the paper were measured by the above-described methods.
The measured values are the average of 10 measurements. The results are shown in Table 9.

[0055]

[Table 9]

[Papermaking method-3] Using a pulp slurry obtained by mixing a used paper pulp slurry and a TMP pulp slurry in a weight ratio of 50/50, 0.3 to 0.8 parts of a papermaking paper quality improver was added per 100 parts of pulp. The sheet preparation and each item were evaluated according to Method-1. Table 10 shows the results.

[0057]

[Table 10]

From Tables 7 to 10, according to the papermaking paper quality improver of the present invention, waste paper pulp and virgin pulp (LBK)
It can be seen that a pulp sheet having improved bulk, whiteness and opacity can be obtained in both P) and mixed pulp of waste paper pulp and virgin pulp (TMP). In addition, Example 31 (an example using a compound satisfying the standard degree of improvement in whiteness and standard opacity), Example 37 and Example 40 (Example in which the amount of the paper quality improving agent added is 0.3% vs. pulp) In the above, a pulp sheet having improved whiteness and opacity was obtained.

[0059]

According to the present invention, even if a small amount is added, the paper quality can be improved to achieve at least two of the improvement of bulk, the improvement of whiteness and the improvement of opacity, etc., which are required by reducing the weight of paper and increasing the use of waste paper pulp. An agent is provided. According to the papermaking paper quality improver of the present invention, a pulp sheet having improved bulk, whiteness and opacity can be obtained.

[Procedure amendment]

[Submission date] April 28, 2000 (200.4.2
8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 4

[Correction method] Change

[Correction contents]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiyuki Nishimori 1334 Minato, Wakayama-shi, Wakayama Prefecture Inside Kao Corporation Research Laboratory (72) Inventor ▲ Taka ▼ Bridge Hirotoshi 1334 Minato, Wakayama-shi, Wakayama Prefecture Kao Corporation F Laboratory Term (reference) 4L055 AG34 AG35 AG39 AG72 AG86 BD10 EA08 EA11 EA29 EA30 EA32 EA40 FA12 FA16

Claims (9)

[Claims] 1. A compound having a water separation degree of 4% or more as defined below, and a compound having two or more of the following (i) to (iii) to improve the paper quality, and before the paper making step: Papermaking paper quality improver internally added in (i) Standard bulk improvement of 0.02 g / cm ³ or more (ii) Standard whiteness improvement of 0.5 point or more (iii) Standard opacity improvement of 0.5 point or more Water separation (%) = (α ₀ −α) / Α ₀ × 100 α: Moisture content of a wet sheet obtained by adding 5 parts by weight of a compound serving as a papermaking paper quality improver to 100 parts by weight of pulp α ₀ : A compound serving as a papermaking paper quality improver Moisture content of wet sheet obtained by making paper without adding to pulp 2. The method according to claim 1, wherein the compound is (A) an organosiloxane, (B)
Glyceryl ether, (C) amide, (D) amine, (E) amine salt, (F) quaternary ammonium salt, (G) imidazole,
(H) an ester of a polyhydric alcohol and a fatty acid, and (I) an ester of a polyhydric alcohol and a fatty acid, wherein the ester 1
The papermaking paper quality improver according to claim 1, which is selected from the group consisting of alkylene oxide addition esters having an alkylene oxide group having 2 to 4 carbon atoms having an average of more than 0 mol and less than 12 mol per mol. 3. The papermaking quality improving agent according to claim 1, which comprises one or more compounds selected from (a) anionic surfactant and (b) cationic surfactant. 4. A bulk improver for papermaking comprising the compound according to claim 1. 5. A papermaking whiteness improver comprising the compound according to claim 1 or 2. 6. An opacity improver for papermaking comprising the compound according to claim 1. 7. A method for producing a pulp sheet, comprising adding the papermaking paper quality improver according to any one of claims 1 to 3 before the papermaking step. 8. A pulp to which the papermaking paper quality improving agent according to any one of claims 1 to 3 and an agent for promoting the fixing of the papermaking paper quality improving agent to a pulp sheet are added before any of the papermaking steps. Sheet manufacturing method. 9. A pulp sheet produced by adding the paper quality improving agent according to any one of claims 1 to 3 before the paper making step.