JP2003286680A - Sticking prevention agent and offset printing paper sheet applied with surface-treating agent containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a sticking prevention agent suppressing a sticking trouble on offset printing even by applying it on an offset printing paper sheet which has to be applied with a large applying amount of a surface treating agent containing a water soluble polymer such as starch for imparting a surface strength (e.g. a newspaper paper for the offset printing) and not inhibiting the effect of the surface-treating agent, and the offset printing paper sheet applied with the surface-treating agent containing the same. <P>SOLUTION: A method for preventing the sticking is to apply the surface- treating agent containing the sticking prevention agent consisting mainly of a resin acid and/or a resin acid derivative and the water soluble polymer such as starch on the stock paper sheet for the offset printing. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an anti-nappari agent which is effective for preventing troubles in the offset printing of a paper coated with a surface treating agent such as starch, and a surface containing the anti-nappari agent. The present invention relates to an offset printing paper coated with a treatment agent and free from troubles during offset printing.

[0002]

2. Description of the Related Art In recent years, as awareness of environmental problems has increased, efforts have been made in the paper manufacturing industry to increase the utilization rate of waste paper as a raw material for papermaking from the viewpoint of resource saving. However, newsprint produced from waste paper pulp containing a large amount of fine fibers as a raw material has a problem that paper dust is generated during printing.

Newspapers have a conventional basis weight of 43 g /
Since the transition from ultra-lightweight paper of m ² to ultra-lightweight paper of basis weight 40 g / m ² , opacity, which is an important paper quality such as newsprint, tends to decrease. Therefore, a treatment for maintaining the opacity is performed by increasing the blending ratio of the filler. However, this blended filler also causes the generation of paper dust.

In order to suppress such paper dust, in newsprint paper or the like, a surface treatment agent such as starches such as oxidized starch is applied to the paper surface by a gate roll coater or the like to improve the strength, thereby The amount of paper dust generated is reduced.

For printing paper such as high-quality paper and medium-quality paper, a surface treatment agent such as oxidized starch is generally applied to the surface of the paper in order to improve printability.

Appropriate amounts of these surface treatment agents applied to various printing papers differ depending on the type of the paper, but it is generally known that increasing the amount of the surface treatment improves the surface strength of the paper. Has been. However, printing paper coated with a high amount of surface treatment agent dissolves the surface treatment agent with dampening water during printing when offset printing is performed, resulting in adhesiveness on the paper. However, there is a concern that printing paper sticks to the blanket and that paper sticks to each other, so-called nepparing trouble, which hinders printing work. In addition, even after printing, if the paper is stored under high humidity conditions, there is a problem of blocking due to adhesion of papers.

[0007] As a means for preventing such troubles in paper, introduction of a reactive functional group such as a methylol group, an aldehyde group or an epoxy group into a surface treatment agent, or a melamine, formaldehyde or glyoxal having such a functional group. There is a method of making the surface treatment agent water resistant by using glycerin diglycidyl ether or the like together with the surface treatment agent. These functional groups increase the insolubility of the surface treatment agent in water and improve the water resistance of the paper surface. However, on the other hand, the molecular weight of the surface-treating agent increases due to the cross-linking reaction of the functional group, and the tackiness when kept in a wet state is rather high. Therefore, the problem of nepparing trouble has not been solved. Therefore, it is the current situation that printing is performed using a printing paper coated with a surface treatment agent in a range of low coating amount that does not cause problems with Nepperi trouble,
With such a low coating amount, sufficient surface strength cannot be imparted, and it is not always satisfactory as a measure for preventing the generation of paper dust.

Japanese Unexamined Patent Publication (Kokai) No. 6-199295 discloses a method in which a substituted succinic acid is mixed with a surface treatment agent and applied.
Substituted succinic acid anti-nappari agents are known to inhibit the effect of surface sizing agents and reduce the water absorption resistance of newsprint, and they are able to impart low neppar strength and high water absorption resistance at the same time. Has been long awaited.

[0009]

DISCLOSURE OF THE INVENTION The present invention provides offset printing even when a desired paper surface strength is obtained and a surface treatment agent is applied in an amount sufficient to prevent paper dust generation. An anti-nepperizing agent that imparts sufficient water absorption resistance without hindering the neppery trouble at the time, and that does not inhibit the effect of the surface sizing agent, and an offset by applying a surface treatment agent containing the anti-nipparing agent. An object of the present invention is to provide an offset printing paper which has both water-absorption resistance and reduction of neppery strength even at the time of printing, and has no nepparing trouble.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to solve the above-mentioned problems of the prior art, and as a result,
It was found that the above object can be achieved by using a resin acid and / or a resin acid derivative in combination with a surface treating agent such as starch, and completed the present invention.

That is, the present invention provides (1) resin acid and / or
Or an anti-nappari agent composed of a resin acid derivative, (2)
The present invention relates to an offset printing paper obtained by applying and drying a surface treatment agent containing an anti-nipparing agent composed of a resin acid and / or a resin acid derivative.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The anti-nappari agent of the present invention comprises a resin acid and / or a resin acid derivative.

As the resin acid, tall oil rosin obtained by fractional distillation of tall oil recovered as a by-product in a kraft pulp mill, or wood rosin obtained as a distillation residue when producing wood turpentine from the extraction of pine stumps. The main component is the resin acidic component belonging to tricyclic diterpenes such as. Examples of the tricyclic diterpenes include abietic acid-type abietic acid, neoabietic acid, palustric acid, levopimaric acid, dehydroabietic acid and pimaric acid-type pimaric acid, isopimaric acid, and sandaracopimaric acid. further,
Examples thereof include so-called reinforced rosin obtained by adding maleic anhydride or fumaric acid to the above tricyclic diterpene.

Examples of the resin acid derivative include resin acids such as ammonia, methylamine, ethylamine, dimethylamine, triethylamine, morpholine, ethanolamine, diethanolamine and triethanolamine, or amines such as sodium hydroxide and potassium hydroxide. The resin acid salt with an alkali metal salt is mentioned. Also, alcohols having 24 or less carbon atoms, for example, methanol, ethanol, propanol, butanol, pentanol, hexanol, cyclohexanol, octanol, 2-ethylhexanol, octanol, lauryl alcohol,
Resin acid monoesters with aliphatic monohydric alcohols such as stearyl alcohol, aromatic monohydric alcohols such as benzyl alcohol, polyhydric alcohols such as ethylene glycol, propanediol and glycerin, and unsaturated alcohols such as allyl alcohol and oleyl alcohol. , Resin acid monoester salts, resin acid diesters and the like. Furthermore, monodocosylamine, didicosylamine, monoeicosylamine, dieicosylamine, monostearylamine, distearylamine, monopalmitylamine, dipalmitylamine, monomyristylamine, dimyristylamine, monododecylamine, didodecyl. Amine, monodecylamine, didecylamine, monohexylamine, dihexylamine, monodococenylamine, didocenylamine, monoeicosenylamine, dieicosenylamine, monooleylamine, dioleylamine, monohexedecenylamine, dihexe Decenylamine, monotetradecenylamine, ditetradecenylamine, monododecenylamine, didodecenylamine, monodecenylamine, didecenylamine, monooctenylamine,
Amidated or imidized products with primary or secondary amines having an alkylamine group or alkenylamine group having 6 to 12 carbon atoms such as dioctenylamine, monohexenylamine, dihexenylamine, etc., and further reaction products with epiclohydrin, etc. Is mentioned.

The resin acid and the resin acid derivative which are the main components of the anti-nappari agent of the present invention can be used alone or in combination of two or more kinds. Among the resin acids and resin acid derivatives, those having low hydrophilicity are
If necessary, it can be used by emulsifying with a suitable emulsifier.

In the present invention, a polyvalent metal salt and / or a polyvalent metal complex salt may be used in combination with the resin acid and / or the resin acid derivative as the anti-nappariness agent.

Examples of the polyvalent metal salts include inorganic acid salts of polyvalent metals such as zinc, cadmium, cobalt, nickel, copper, zirconium, aluminum (eg, carbonates, phosphates, sulfates, ammonium salts, etc.). , Organic acid salts (eg,
Acetate, oxycarboxylate, etc.), oxide, hydroxide,
Examples thereof include chloride. Among these, zinc, zirconium, inorganic acid salts, organic acid salts, oxides of aluminum,
Hydroxides are preferred, especially carbonates. Specific examples of the salts of these polyvalent metals include zinc chloride, zinc nitrate, zinc sulfate, zinc ammonium chloride, basic zinc carbonate, cadmium chloride, cadmium nitrate, cadmium sulfate, cobalt chloride, cobalt nitrate, cobalt sulfate, and cobalt carbonate. Nickel chloride, nickel nitrate, nickel sulfate, nickel carbonate, nickel sulfamate, cupric chloride, copper nitrate, copper sulfate, copper pyrophosphate, zirconium acetate, zirconium nitrate, zirconium hydroxide, zirconium carbonate, aluminum chloride, aluminum nitrate, Aluminum sulfate etc. are mentioned. In addition, specific examples of polyvalent metal complex salts include
Examples thereof include zirconyl ammonium carbonate, potassium zirconium carbonate, zinc fluorosilicate, potassium aluminate, sodium aluminate, ammonium alum, and potassium alum.

The amount of the polyvalent metal salt and / or the polyvalent metal complex salt added is such that the resin acid and / or the resin acid derivative 100 is added.
5 to 100 parts by weight, preferably 10 to 50 parts by weight,
Parts by weight. Even if added in an amount of more than 100 parts by weight, the effect of preventing Nappari will not be further improved.

The polyvalent metal complex salts exemplified above can be added to the resin acid and / or the resin acid derivative as they are prepared in advance, or in addition to the polyvalent metal salt and the volatile complexing agent. It is also possible to prepare a complex salt of a valent metal and add it to the resin acid and / or the resin acid derivative. Further, the polyvalent metal complex salt can also be prepared by sequentially or simultaneously adding the polyvalent metal complex salt and the volatile complexing agent to the resin acid and / or the resin acid derivative.

Examples of the volatile complexing agent include volatile amines such as ammonia, methylamine, ethylamine, dimethylamine, triethylamine, morpholine, ethanolamine, diethanolamine and triethanolamine. Of these, ammonia is particularly preferable.

The addition ratio of the volatile complexing agent to the polyvalent metal salt is usually about 0.5 to 2 equivalents of the coordination number of the polyvalent metal. If it is less than 0.5 equivalents, undissolved substances are generated when preparing a polyvalent metal complex salt, and even if it is used in excess of 2 equivalents, it is unnecessary for forming a polyvalent metal complex salt, leading to a decrease in the active ingredient. Only. The amount of the prepared polyvalent metal complex salt added is usually 100 parts by weight or less based on 100 parts by weight of the resin acid and / or the resin acid derivative.

The anti-nepparizing agent containing the resin acid and / or the resin acid derivative thus obtained and a salt of a polyvalent metal and / or a complex salt of a polyvalent metal as active ingredients is a resin acid and / or
Alternatively, a resin acid derivative and a salt of a polyvalent metal and / or a complex salt of a polyvalent metal are independently present, and when a resin acid and / or a resin acid derivative has a carboxyl group, In some cases, the complex salt of the resin acid derivative and the polyvalent metal (or the polyvalent metal compound and the volatile complexing agent) forms a metal complex of the resin acid and / or the resin acid derivative. In the present invention, any of these cases can be used as an anti-nappari agent, and each of them can also be used in an appropriate combination.

In the present invention, by including the anti-nepperizing agent in the surface treating agent, even when the coating amount of the surface treating agent is large, the nepparing strength is low and the water absorption resistance is high, and the offset printing is performed. It is possible to manufacture an offset printing paper excellent in the effect of preventing the nappari.

The surface treatment agent used in the present invention preferably contains a water-soluble polymer in order to improve the surface strength of offset printing paper. As water-soluble polymer,
For example, starch, enzyme-modified starch, oxidized starch, esterified starch, etherified starch (hydroxyethylated starch, etc.),
Starch such as dialdehyde starch, phosphate esterified starch, cationized starch, polyvinyl alcohol such as fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, carboxymethyl cellulose, anionic polyacrylamide, cationic polyacrylamide, Examples include various natural or synthetic polymer substances such as amphoteric polyacrylamide, which are used alone or
Two or more kinds can be used in combination.

The water-soluble polymer used in the surface treating agent of the present invention plays a main role in improving surface strength (in other words, suppressing paper dust). However, the water-soluble polymer also causes nepparing trouble. Surface strength improvement effect,
Considering the balance with Neppari, as the water-soluble polymer, starches can be preferably used among the above-mentioned examples, and among them, oxidized starch, etherified starch and esterified starch are most preferable.

In the present invention, a surface sizing agent may be contained in the surface treatment agent for the purpose of imparting sizing properties to the printing paper. As surface sizing agent, styrene / (meth)
Acrylic acid copolymer (Note that (meth) acrylic acid is
It means "acrylic acid and / or methacrylic acid". ), Styrene / (meth) acrylic acid ester copolymer, styrene / (meth) acrylic acid / (meth) acrylic acid ester copolymer, styrene / maleic acid copolymer,
Styrene / maleic acid half ester copolymer, styrene /
Maleic acid ester copolymer, ethylene / (meth) acrylic acid copolymer, isobutylene / (meth) acrylic acid copolymer, n-butylene / (meth) acrylic acid / (meth)
Examples thereof include acrylic acid ester copolymers, propylene / maleic acid copolymers, ethylene / maleic acid copolymers, and the like. These copolymers may be used as sodium salt, potassium salt, or ammonium salt.

Further, as long as it does not affect the present invention, a preservative, an antifoaming agent, a UV inhibitor, an anti-fading agent, an optical brightener,
Auxiliaries and fillers such as viscosity stabilizers, lubricants and anti-slip agents may be included.

The amount of the anti-nappari agent of the present invention to be used is usually 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, based on 100 parts by weight of the water-soluble polymer such as starch. . If the amount is less than 0.1 part by weight, there is no sufficient effect of preventing nepparity, and if the amount is more than 50 parts by weight, the effect is not further improved. However, it is necessary to increase the coating amount on the paper in order to obtain the desired effect of suppressing the Nepperi, which leads to an increase in cost, which is not preferable.

The method for applying the anti-nappari agent of the present invention is not particularly limited, but (1) when applying the aqueous solution of the surface treating agent containing the anti-neppar agent to the paper surface, A method in which the stopping agent as it is, emulsified, or appropriately diluted is mixed and added, and the mixed solution is applied to paper, (2) an aqueous solution of a surface-treating agent containing no nepparizing agent (1) It is also possible to adopt a method of applying the anti-nappari agent to the paper previously coated by the same method as above. The method (1) is preferable in terms of industrial convenience. The coating equipment is a size press coater, tab size, calendar size, wire bar coater, air knife coater, roll coater (gate roll coater), blade coater (bill blade coater), spray, etc., among these, surface treatment It is preferable to use a blade coater or a roll coater because the agent can be applied at a high speed and a high concentration, the yield on the surface of the paper layer is high, and the heat of drying is small. Further, among the roll coaters, the gate roll coater can be simultaneously coated on both sides using different kinds of surface treatment agents, and can be improved in printability such as smoothness, whiteness, gloss, and ink acceptability. Furthermore, since high-concentration coating is possible, water migration into the paper layer is small and paper breakage and wrinkling during coating are less likely to occur, which is preferable.

The concentration and viscosity of the surface-treating agent coating liquid containing the anti-nappariness agent of the present invention applied to the surface of paper are not particularly limited, but usually the concentration is about 0.5 to 20% by weight, Preferably 1 to 15% by weight, viscosity about 1000 cps (25
C.) or less, preferably 200 cps (25.degree. C.) or less.

The coating amount of the surface-treating agent of the present invention varies depending on the type of paper, but the solid content of the water-soluble polymer and the anti-nappariness agent applied to the paper is usually 0.005 to 5.0 g /
It is good to adjust to about m ² , preferably 0.01 to 2.0 g / m ² .

The base paper for printing paper coated with the surface treatment agent containing the anti-nepparizing agent of the present invention is not necessarily limited to newsprint base paper, but the effect of the present invention can be obtained in the case of newsprint base paper. Since it is noticeable, the following is mentioned.

The newsprint base paper used in the present invention is ground pulp (GP), thermomechanical pulp (TMP),
30% by weight of mechanical pulp (MP) such as semi-chemical pulp
On the other hand, the remaining part is a chemical pulp (CP) typified by kraft pulp (KP), a deinked pulp (DIP) obtained by deinking waste paper containing these pulps, and spoiled paper from the papermaking process. The recovered pulp obtained by disaggregation is mixed alone or in an arbitrary ratio.
The DIP blending ratio may be within an arbitrary range, but the NEPPAR inhibitor of the present invention has a DIP blending ratio of 50 to 10
A good effect is exhibited even in the range of 0% by weight. Generally D
The higher the blending ratio of IP, the worse the Neppari tends to be. One of the reasons for this is considered to be that the blending ratio of virgin mechanical pulp containing a resin acid analogue decreases.

The basis weight of newsprint base paper is not particularly limited, but is about 34 to 45 g / m ² .

If necessary, generally known publicly known papermaking fillers and papermaking chemicals can be appropriately added to the newsprint base paper. As the filler, white carbon, clay, silica, talc, titanium oxide, calcium carbonate, synthetic resin filler (vinyl chloride resin, polystyrene resin, urea formalin resin, melamine resin, styrene / butadiene copolymer resin, etc.), etc. Can be added. Especially in neutral papermaking, calcium carbonate is effective. Also,
Paper-making chemicals include polyacrylamide polymer, polyvinyl alcohol polymer, cationized starch, urea /
Paper strength agents such as formalin resin and melamine / formalin resin; salts of acrylamide / aminomethyl acrylamide copolymers, cationic starch, polyethyleneimine, polyethylene oxide, acrylamide / sodium acrylate copolymer etc. Improver, rosin sizing agent, emulsion sizing agent, alkyl ketene dimer (AKD), sizing agent such as alkenyl succinic anhydride (ASA), aluminum sulfate (sulfate band), UV inhibitor, anti-fading agent, defoaming agent, etc. You may contain the auxiliary agent etc. of. The physical properties of the base paper need to be printable by an offset printing machine, and may be those having physical properties such as tensile strength, tear strength, elongation and the like of ordinary newspapers.

The newsprint base paper of the present invention may be an acidic papermaking newsprint base paper, or may be a neutral or alkaline papermaking newsprint base paper.

Regarding the type of paper to which the anti-nappaly agent of the present invention is applied, it is possible to use various kinds of paper such as offset printing newsprint paper, notebook paper, book paper, foam paper, PPC paper and the like. Among these, the printing of newsprint for offset printing places importance on operability, and a large amount of printing must be performed in a short time. Therefore, by applying the anti-nappariness agent of the present invention to the newsprint for offset printing, it is possible to reduce the nepparing strength and at the same time impart water absorption resistance. Therefore, even when printing using an offset printing machine, it is possible to prevent the Nappari trouble that sticks to the blanket due to the increase in the adhesiveness of the paper surface due to the transfer of dampening water during offset printing of the surface treatment agent, There is a remarkable effect that it is possible to prevent interruption of printing due to paper break.

[0038]

EFFECTS OF THE INVENTION By using the anti-nappari agent of the present invention,
Even when it is applied to various types of paper (for example, newsprint) for which a surface treatment agent such as starch has to be applied in a large amount, it is possible to provide an offset printing paper which does not cause trouble in offset printing. . Furthermore, in the manufacture of offset printing paper, it is possible to prevent interruption of printing due to paper breakage, and it is possible to improve work efficiency.

[0039]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, parts and% in each example are
Represents parts by weight and% by weight, respectively.

[Example 1] <Formation of base paper for foam paper> Hardwood bleached kraft pulp was disaggregated with a refiner to obtain a freeness of 400 ml (CSF).
/ Canadian standard freeness) adjusted pulp slurry, rosin emulsion sizing agent (trade name: SNP-7
73, Arakawa Chemical Industry Co., Ltd.) 0.2 per dry pulp
%, Followed by addition of 0.8% sulfuric acid band, and cationized starch (trade name: Cato-3210, National
l Starch and Chemicals)
0.4% was added, 5% kaolin was added as a filler, and cationic polyacrylamide (trade name: Percol-162, Ciba Specialty) was added as a yield improver.
Chemicals) added 0.014%, bentonite (trade name: Hydrocol-0, Ciba Sp
0.1% (made by ecological Chemicals) is added and papermaking is performed by an on-top paper machine, and the basis weight is 108 g.
A foam paper base paper of / m ² was obtained. <Application of surface treatment agent> Oxidized starch (trade name: SK-20, manufactured by Nippon Corn Starch Co., Ltd.) as a surface treatment agent, rosin emulsion sizing agent (trade name: Hersize NES500-F, Harima Kasei ( stock)
Was added to the starch in an amount of 3%, mixed and diluted to obtain a surface treatment agent coating solution having a solid content concentration of 12%. Using the gate roll coater, the surface treatment agent coating liquid thus obtained was applied on both sides of the above-mentioned foam paper base paper at 800 m / min.
Foam paper was obtained by applying a coating amount of 1.7 g / m ² on both sides and drying at a coating speed of 1 minute.

Example 2 A rosin emulsion sizing agent (trade name: Hersize NES50) as an anti-nappari agent
Foam paper was obtained in the same manner as in Example 1 except that 6% of 0-F, manufactured by Harima Kasei Co., Ltd. was added to the starch for coating.

[Comparative Example 1] A foam paper was obtained in the same manner as in Example 1 except that the anti-nappari agent was not applied.

[Example 3] <Papermaking of newsprint base paper> 12 parts of softwood kraft pulp, 22 parts of thermomechanical pulp, and 66 parts of deinked waste paper pulp were mixed and disintegrated with a refiner to give a freeness of 110 m.
2% white carbon as a filler was added to the pulp slurry adjusted to l (CSF / Canada standard freeness) per absolutely dry pulp, and then papermaking was performed with a twin wire type paper machine, and a basis paper of 42 g / m ² basis weight Got <Coating of surface treatment agent> As the surface treatment agent, oxidized starch (trade name: SK-20, manufactured by Nippon Corn Starch Co., Ltd.), and styrene-based sizing agent (trade name: KN-520, manufactured by Harima Chemicals Co., Ltd.) ) To 20% of starch,
Further, a rosin emulsion sizing agent (trade name: Hersize NES500-F, manufactured by Harima Kasei Co., Ltd.) was added as an anti-nappari agent so as to be 5% with respect to the starch,
It was diluted to obtain a surface treatment agent coating liquid having a solid content concentration of 8.0%.
The surface treating agent coating solution thus obtained was applied to both sides of the above-mentioned newsprint base paper (basis weight 42 g / m ² ) using a gate roll coater at a coating speed of 1200 m / min. The target was 0.50 g / m ² , and the coating was dried to obtain newsprint for offset printing.

[Example 4] A rosin emulsion sizing agent (trade name: Hersize NES50) as an anti-nappari agent
A newsprint for offset printing was obtained in the same manner as in Example 3 except that 0-F and Harima Kasei Co., Ltd. were added so as to be 10% relative to the starch.

[Comparative Example 2] A newsprint for offset printing was obtained in the same manner as in Example 3 except that the anti-nappari agent was not applied.

Comparative Example 3 A newsprint for offset printing was obtained in the same manner as in Example 3 except that a saponified octenyl succinic anhydride was used as an anti-nepperizing agent.

Comparative Example 4 A newsprint for offset printing was obtained in the same manner as in Example 3 except that a saponified octenyl succinic anhydride was used as an anti-nappari agent.

For the foam sheets of Examples 1 and 2 and Comparative Example 1, the Steckigt sizing degree,
The Nappari strength was measured and the results are shown in Table 1. Example 3
4 and Comparative Examples 2 to 4 were measured for their drip absorption and neppar strength by the methods described below, and the results are shown in Table 2. -Measurement of Steckigt sizing degree: in accordance with JIS P 8122: 1976. -Measurement of drip water absorption: According to Japan TAPPI No. 33 (Testing method for water absorption rate of absorbent paper), the amount of dropped water was 1 μl. -Measurement of Nappari strength: Two sheets of foam paper or newsprint for offset printing were cut into 4 x 6 cm pieces, the coated surfaces were immersed in water at a temperature of 20 ° C for 5 seconds, and then the coated surfaces were brought into close contact with each other. On both outer sides, form paper in the case of foam paper and base paper in the case of newsprint for offset printing are overlaid and passed through a roll at a pressure of 50 kg / m ² at 25 ° C, 60 ° C.
The humidity was adjusted to 24 hours with% RH. After making a sample piece of 3 × 6 cm,
The measurement was carried out with a tensile tester under conditions of a tensile speed of 30 mm / min. The larger the measured value, the harder it is to peel off (in other words, the stronger the adhesiveness). In the present invention, the neppar strength is 590 mN / 3 cm (60 gf / 3 cm)
The following was defined as "excellent peelability".

[0049]

[Table 1]

[0050]

[Table 2] As shown in Table 1, the foam paper coated with the surface-treating agent containing the anti-nepparizing agent of the present invention had a low neppar strength and a Steckigt sizing degree equal to or higher than that. Similarly, as shown in Table 2, the offset printing newsprint coated with the surface treating agent containing the anti-nepparizing agent of the present invention has low neppar strength, and the saponified octenyl succinic anhydrides of Comparative Examples 3 and 4 are used. The drip water absorption was also higher than that of the newsprint for offset printing coated as an anti-nappari agent.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hideki Fujiwara             5-21-1 Oji, Kita-ku, Tokyo Nippon Paper Industries             Technical Research Institute Co., Ltd. F term (reference) 4L055 AA02 AA03 AC03 AC06 AC09                       AG48 AG50 AG63 AH13 AH37                       AJ02 BB03 BE08 FA11 FA14                       GA11 GA15 GA16 GA50

Claims (3)

[Claims] 1. An anti-nepparizing agent containing a resin acid and / or a resin acid derivative as a main component. 2. An offset printing paper obtained by coating a base paper for printing paper with a surface treatment agent containing an anti-nepperizing agent containing a resin acid and / or a resin acid derivative as a main component, and drying. 3. The offset printing paper according to claim 2, which contains starch as a surface treatment agent.