JP7508354B2 - Paper treatment agent and paper using the same - Google Patents

Description

The present invention relates to a paper treatment agent and paper using the same.

Conventionally, there are known products that treat paper with paper treatment agents whose main component is a moisturizing agent, thereby giving the paper a moisturizing feel and softness compared to ordinary dry tissues, toilet paper, etc. A representative product is lotion tissue, which is a moisturizing tissue made by applying a lotion as a paper treatment agent to tissue base paper. Since it has a moist and soft texture and greatly improves the feeling of use, it has become popular as a seasonal product in winter to prevent hay fever and influenza, and in recent years, its use has expanded from being used mainly for blowing noses to everyday use, and it is becoming a year-round product. As a result, the texture changes between summer and winter, which have different humidity environments, and the quality cannot be maintained at a constant level, and there has been a demand for a product that can maintain its texture even in low humidity environments.

Moisturizing tissues often use polyhydric alcohols such as glycerin or polyethylene glycol (PEG), especially glycerin, which is an inexpensive, safe and excellent moisturizing agent. This humectant enhances the moisture absorption and moisture retention of paper, giving the paper a moist and soft texture. The texture of the material and the feel that people get when they touch it have a major impact on the feel of moisturizing tissues when used, and is the most important quality that adds value to the product.

Lotion tissues become soft by the moisture absorption of the moisturizer glycerin and by incorporating softening ingredients, and the softness of moisturizing tissues is achieved by the reduction in hydrogen bonds between the pulp due to the increased moisture content of the coated paper. The amount of moisture absorbed by the moisturizer depends on the humidity of the external environment, and in low-humidity environments moisture is lost from the tissue and the hydrogen bonds between the pulp are reconstructed, making the paper harder than in high-humidity environments. This causes deterioration of the texture in low-humidity environments, which has been an issue.

In addition to the moisturizer, moisturizing tissues contain various bases such as surfactants, oily components such as hydrocarbons and esters, and thickeners to improve texture, such as softness and surface feel (smoothness). Surfactants are the components that mainly determine the characteristics of the texture and can impart softness. Oily components are the components that mainly determine changes in texture and can impart smoothness. However, it has been difficult to impart such texture while preventing deterioration of the texture in low humidity environments.

Furthermore, emulsification is required to uniformly mix the main moisturizing agent with these bases and maintain a stable state from production to transportation and application, while preventing unevenness during application. However, preparing an emulsion system based on a moisturizing agent is extremely difficult, and it is also extremely difficult to achieve both a base balance for adjusting the emulsion and a base balance for improving texture. On the other hand, low-viscosity paper treatment agents are easy to transport and handle, and the amount of treatment agent attached to the treated paper is easy to manage, resulting in good operability. Therefore, there is a need to avoid the deterioration of operability caused by increased viscosity.

As such, there was a demand for technology that could prevent deterioration of texture in low humidity environments, while also providing good stability over time and maintaining appropriate viscosity of the treatment agent.

Various measures have been taken to address these issues. For example, a technology that uses a drug in a gel composition (Patent Document 1), a technology that uses the water-absorbing properties of water-soluble polymers to improve moisturizing (Patent Document 2), a technology that uses oily substances and water-soluble waxes to reduce softness and friction (Patent Document 3), and a technology that incorporates ingredients such as sucrose fatty acid esters, branched alcohols, linear higher fatty acids, and higher alcohols to improve softness and texture in low humidity environments (Patent Documents 4 to 8).

Patent No. 3950400 Japanese Patent No. 4570669 Japanese Patent Application Laid-Open No. 10-226986 JP 2014-208921 A JP 2007-107173 A JP 2016-74999 A JP 2019-99938 A Japanese Patent No. 3824656

However, in Patent Document 1, uniform application of the gel composition to paper involves complicated processes. In addition, the gel composition is difficult to transport, which is a problem. In Patent Document 2, the water-soluble polymer requires time and effort to be uniformly dispersed, complicating the drug manufacturing process. In addition, the water-soluble polymer causes significant thickening, so the amount of the water-soluble polymer must be limited. In Patent Document 3, the water-soluble wax has a high viscosity, which impairs the fluidity and uniform application of the drug, and deteriorates operability. In Patent Documents 4 to 7, the above-mentioned components have the advantage of being easily incorporated into the moisturizing agent, and can contribute to maintaining softness in a low-humidity environment, but the effect is not sufficient. Patent Document 8 uses oily components rather than polyhydric alcohols as the main components, and the texture is not flexible or moist, and the moisture retention is insufficient.

The present invention was made in consideration of the above circumstances, and aims to provide a paper treatment agent that imparts flexibility and a moist feel to paper, reduces deterioration in texture due to a decrease in moisture content caused by a humid environment of the treated paper, and further has good stability over time and can maintain an appropriate viscosity, as well as paper using the same.

In order to solve the above problems, the inventors conducted extensive research and discovered that by incorporating a polyhydric alcohol as the main component, it is possible to impart a moist feel and flexibility to paper, and by incorporating an oil-based component with water-holding properties, it is possible to maintain moisture and maintain the moist feel and flexibility even in low humidity environments, and further, by combining this with a nonionic surfactant with an HLB in a specific range, it is possible to incorporate the water-holding oil-based component with good stability into the paper treatment agent and maintain the appropriate viscosity, which led to the completion of the present invention.

That is, the paper treating agent of the present invention is a paper treating agent containing (A) a polyhydric alcohol as a main component,
The treatment agent is characterized by containing (B) at least one water-containing oil component selected from petrolatum, lanolin, an ester compound of a fatty acid including a dimer acid and a polyhydric alcohol, lanolin alcohol, and lanolin fatty acid, in an amount of 0.40 to 25% by mass based on the total amount of the components other than water in the treatment agent, and (C) a nonionic surfactant having an HLB of 12 or more.
The paper of the present invention is characterized by being treated with the paper treating agent.

The present invention can impart flexibility and a moist feel to paper and reduce deterioration in texture due to a decrease in moisture content caused by the humid environment of the treated paper. Furthermore, the paper treatment agent has good stability over time and can maintain an appropriate viscosity.

The present invention is described in detail below.

The paper treatment agent of the present invention is a paper treatment agent containing (A) a polyhydric alcohol as the main component, and (B) a water-holding oil component and (C) a nonionic surfactant are essential. Hereinafter, these will be referred to as component (A), component (B), and component (C), respectively.

By blending component (A), a polyhydric alcohol, as the main component, the paper is given a moist feel and flexibility. By blending component (B), an oil-based component with water-holding properties, the paper can retain moisture even in low humidity environments, and maintain a moist feel and flexibility. By blending component (C), a nonionic surfactant with an HLB of 12 or more, the water-holding oil-based component (B) can be blended stably into the paper treatment agent, and the viscosity can also be maintained appropriately.

In the paper treatment agent of the present invention, the polyhydric alcohol of component (A) is a moisturizing agent that enhances the hygroscopicity and moisture retention of paper and gives the paper a moist feel and flexibility, and is the main component of the paper treatment agent.

Here, the main component means that, among the various additive components that are the raw materials of the paper treatment agent, component (A) is blended in the largest amount by mass. Among them, the content of component (A) is preferably 50% by mass or more, more preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more, based on the total amount of the paper treatment agent excluding water. Note that the blended components of the paper treatment agent indicate the values of the active ingredients excluding water.

Examples of the polyhydric alcohol of component (A) used in the present invention include glycerin, diglycerin, triglycerin, polyglycerin, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, polypropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,2-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polyoxyethylene glycerin ether, isoprene glycol, pentaerythritol, trimethylolpropane, etc. Also, sugar alcohols and sugars may be used, and examples of sugar alcohols include sorbitol, inositol, glucosyl trehalose, xylitol, erythritol, mannitol, lactitol, fructose, oligosaccharide alcohol, maltitol, reduced palatinose, reduced starch syrup, reduced starch hydrolysate, etc. Examples of sugars include fructose, glucose, lactose, xylose, psicose, maltose, starch syrup, oligosaccharides, maltose, trehalose, lactose, palatinite, sucrose, isomerized sugar, isomaltooligosaccharides, fructooligosaccharides, galactooligosaccharides, xylooligosaccharides, lactofructose oligosaccharides, soybean oligosaccharides, raffinose, stevia, licorice, saccharin, aspartame, acesulfame K, sucralose, etc. These may be used alone or in combination of two or more.

Among these, glycerin is preferred. When glycerin is used as a moisturizer, the ratio of glycerin to the total amount of moisturizer is preferably 80% by mass or more, and more preferably 90% by mass or more. Examples of moisturizers to be used in combination with glycerin include sorbitol.

In the paper treatment agent of the present invention, a component other than the polyhydric alcohol of component (A) may be used in combination with component (A) as a moisturizing agent. Examples of such moisturizing agents include amino acids, hygroscopic alkalis and acids, and their salts. Examples of amino acids include glycine, valine, leucine, isoleucine, serine, threonine, phenylalanine, arginine, lysine, aspartic acid, glutamic acid, cystine, cysteine, methionine, tryptophan, and the like. Examples of hygroscopic alkalis and acids and their salts include pantetheine-S-sulfonate, trimethylglycine, betaine, pyrophosphate, sodium pyrophosphate, chondroitin sulfate, potassium pyrophosphate, hyaluronic acid, sodium hyaluronate, sodium metaphosphate, potassium polyphosphate, sodium pyrrolidone carboxylate, sodium lactate, sodium chloride, calcium chloride, sodium alginate, sodium polyacrylate, and the like. These may be used alone or in combination of two or more.

In the paper treatment agent of the present invention, component (B) is at least one water-holding oil component selected from petrolatum, lanolin, ester compounds of fatty acids including dimer acid and polyhydric alcohols, lanolin alcohol, and lanolin fatty acid. Component (B) has water-holding properties, and by incorporating this component, it is possible to maintain moisture even in low-humidity environments, and to maintain a moist feel and flexibility. Component (B) also improves the texture, such as the feel (smoothness) of the surface of the treated paper.

Examples of petrolatum include those obtained by decolorizing and refining a mixture of hydrocarbons obtained from petroleum. Typical examples include branched-chain paraffin and alicyclic hydrocarbons. Specific examples include white petrolatum described in the Japanese Pharmacopoeia, White Petrolatum S from Kosakai Pharmaceutical Co., Ltd., highly refined petrolatum Sunwhite P-150 and Sunwhite P-200 from Nikko Rica Corporation, Nomcoat W from Nisshin Oillio Group, Ltd., WP-2395, White Protopet 1S, Super White Protopet, Perfecta from Sonneborn LLC, and Chloratum V from Croda Japan Co., Ltd.

Lanolin is a wax secreted from the sebaceous glands of animals covered in wool. Specific examples include Ecolano LN-C, liquid lanolin, Ecolano LN-E, Ecolano LL-E, and refined lanolin, all manufactured by Nippon Fine Chemical Co., Ltd.

Examples of ester compounds of fatty acids containing dimer acid and polyhydric alcohols include ester compounds of fatty acids containing dimer dilinoleic acid and polyhydric alcohols. The ester compounds may be copolymers (copolymers or oligomers). The fatty acids may contain other fatty acids in addition to dimer dilinoleic acid, such as long-chain fatty acids having one carboxy group. Examples of polyhydric alcohols include (poly)glycerin and (poly)alkylene glycol. Specifically, for example, polyglyceryl-2 isostearate/dimer dilinoleic acid copolymer, polyglyceryl dimer dilinoleic acid/stearic acid/hydroxystearic acid, (diethylene glycol/dimer dilinoleic acid) copolymer, etc. can be used. Commercially available products include High Lucent ISDA and NIKKOL GS-WHO from Kokyu Alcohol Kogyo Co., Ltd., and Moisturizing Oligomer Ester D/DC from FANCL Corporation. Among these, ester compounds of fatty acids including dimer dilinoleic acid and polyglycerin, such as polyglyceryl dimer dilinoleate/stearic acid/hydroxystearic acid, are preferred.

Lanolin alcohols include mixtures of higher alcohols and sterols obtained by hydrolysis of lanolin. Specific examples include Lanolin Alcohol A and EcolanoAL-E from Nippon Fine Chemical Co., Ltd., and SUPER HARTOLAN from Croda Japan Co., Ltd.

Lanolin fatty acids include fatty acid mixtures obtained by hydrolysis of lanolin. Specific examples include Lanolin Fatty Acid LIV, Lanolin Fatty Acid DO, Lanolin Fatty Acid W, Lanolin Fatty Acid Soft, Ecolano FW-HHL from Nippon Fine Chemical Co., Ltd., and 18MEA from Croda Japan Co., Ltd.

In the paper treatment agent of the present invention, the content of component (B) is 0.40 to 25% by mass based on the total amount of the treatment agent excluding water. Considering the overall expression of each effect, particularly the ability to maintain moisture and moisturizing and flexibility even in a low humidity environment, the content is 0.40% by mass or more based on the total amount of the treatment agent excluding water, preferably 0.50% by mass or more, and more preferably 0.60% by mass or more. Considering the ability to maintain moisture and moisturizing and flexibility even in a low humidity environment, the ability to stably blend water-holding oil components into the paper treatment agent, and the ability to maintain appropriate viscosity, the content is 25% by mass or less based on the total amount of the treatment agent excluding water, and particularly considering the ability to stably blend water-holding oil components into the paper treatment agent, the content is 20% by mass or less based on the total amount of the treatment agent excluding water, more preferably 15% by mass or less, even more preferably 13% by mass or less, and most preferably 10% by mass or less.

In the paper treatment agent of the present invention, component (C) is a nonionic surfactant with an HLB of 12 or more. By incorporating component (C), the water-containing oil component (B) can be incorporated stably into the paper treatment agent, improving the stability of the paper treatment agent over time. In addition, the increase in viscosity can be suppressed and the viscosity can be kept appropriately low, making the agent easy to transport and easy to handle, and the amount of the agent attached to the treated paper can be easily controlled, improving operability.
The HLB of the component (C) is preferably 13 or more and 18 or less, and more preferably 14 or more and 16 or less.

HLB (Hydrophilic-Lipophilic Balance) is a number that indicates the balance between hydrophobicity and hydrophilicity of a surfactant, and for nonionic surfactants, the value obtained by the Griffin method is used. In the Griffin method, it is calculated based on the formula weight and molecular weight of the hydrophilic group, as HLB = 20 x (weight % of hydrophilic group).

Examples of nonionic surfactants include ethylene glycol fatty acid esters, propylene glycol fatty acid esters, monoglycerin fatty acid esters, diglycerin fatty acid esters, polyglycerin fatty acid esters, organic acid monoglycerides, sorbitan fatty acid esters, sucrose fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene glycerin fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene hydrogenated castor oil, polyoxyethylene castor oil, polyoxyethylene alkyl ethers, polyoxyethylene allyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyether modified silicones, polyoxyethylene fatty acid alkanolamides, and fatty acid alkanolamides. These may be used alone or in combination of two or more.

Among these, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene hydrogenated castor oil, sucrose fatty acid esters, polyglycerin fatty acid esters, and polyoxyethylene alkyl ethers are preferred.

In the paper treatment agent of the present invention, the content of component (C) is preferably 0.1 to 40% by mass based on the total amount of the treatment agent excluding water, taking into consideration the overall expression of each effect. In consideration of the ability to stably blend the water-holding oil component into the paper treatment agent and to maintain the viscosity appropriately, the content is preferably 0.1% by mass or more based on the total amount of the treatment agent excluding water, more preferably 0.2% by mass or more, even more preferably 0.4% by mass or more, and particularly preferably 0.5% by mass or more. In consideration of the ability to maintain the viscosity appropriately, the content is preferably 40% by mass or less based on the total amount of the treatment agent excluding water, and in particular, in consideration of the ability to maintain the viscosity appropriately, the content is preferably 20% by mass or less based on the total amount of the treatment agent excluding water, more preferably 18% by mass or less, and even more preferably 15% by mass or less.

In consideration of the overall manifestation of each effect, it is particularly preferred that the content of component (A) is 80% by mass or more based on the total amount of the treatment agent excluding water, the content of component (B) is 0.5 to 20% by mass based on the total amount of the treatment agent excluding water, and the content of component (C) is 0.2 to 20% by mass based on the total amount of the treatment agent excluding water.

In consideration of the overall expression of each effect, the paper treatment agent of the present invention preferably contains (C') a nonionic surfactant with an HLB of less than 12, and the mass ratio of the (C') component to the (C) component ((C')/(C)) is 0.01 to 10. The lower limit is more preferably 0.03 or more in terms of maintaining an appropriate viscosity. The upper limit is more preferably 3.0 or less in terms of balancing the entire system and increasing the stability of the emulsion.

The HLB of component (C') can be determined by the method described above for component (C). Examples of component (C') include sorbitan fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene hydrogenated castor oil, polyoxyethylene castor oil, and monoglycerin fatty acid esters.

In the paper treatment agent of the present invention, the mass ratio of component (B) to component (C) ((B)/(C)) is preferably 0.005 to 99, taking into consideration the overall expression of each effect. The lower limit is more preferably 0.03 or more in terms of maintaining an appropriate viscosity. The upper limit is more preferably 10 or less, even more preferably 4.0 or less, and most preferably 2.0 or less in terms of increasing the stability of the emulsion.

In the present invention, other components than those mentioned above can be added as raw materials to the paper treatment agent within the range that does not impair the effects of the present invention. Such other components are not particularly limited, but examples include water, nonionic surfactants, cationic surfactants, anionic surfactants, zwitterionic surfactants, oily components, thickeners, antifungal agents, preservatives, defoamers, fragrances, dyes, pH adjusters, extracts, antioxidants, anti-inflammatory agents, inorganic minerals, inorganic salts, water-soluble polymers, etc.

Examples of oily components include hydrocarbons such as solid paraffin and liquid paraffin, oils and fats, esters, silicone oils, waxes, steroids, etc. These may be used alone or in combination of two or more.

Water may or may not be added, but if water is added, it is preferably added so that the moisture content in the paper treatment agent is 1-30% by mass, more preferably 3-25% by mass, and even more preferably 5-20% by mass.

The paper treatment agent of the present invention can be produced by uniformly mixing the raw materials according to conventional methods, for example by stirring and mixing at a temperature at which the raw materials dissolve.

The paper treatment agent of the present invention is sufficient if component (B) is uniformly mixed in component (A) via component (C), and components (B) and (C) may be in a molten state, a solubilized state, an emulsified state, or a dispersed state in component (A), which is the main component.

The paper of the present invention is treated with the paper treatment agent described above. Treating paper with the paper treatment agent of the present invention imparts flexibility and a moist feel to the paper, and reduces deterioration of the texture of the treated paper due to a decrease in moisture content caused by the humid environment. Furthermore, the paper treatment agent has good stability over time and can maintain an appropriate viscosity.

Examples of paper products include tissue paper, toilet paper, facial tissue, pocket tissue, paper handkerchiefs, paper towels, etc.

The basis weight of the paper is preferably 1 to 50 g/m ² , and more preferably 5 to 20 g/m ^2. The number of plies (the number of layers of base paper) is preferably 1 to 5, and more preferably 2 to 3.

Methods for treating paper with paper treatment agents include, for example, coating the paper. Examples of methods for coating paper include transfer and spraying. Examples of methods for coating paper using these methods include flexographic printing, gravure printing, spraying, and rotor dampening. In the flexographic printing method, a flexographic printing machine, which is a type of letterpress printing machine, is used to transfer the paper treatment agent to the paper with a roller equipped with a printing plate made of rubber or synthetic resin with an engraved surface. In the gravure printing method, a gravure printing machine, which is a type of intaglio printing machine, is used to transfer the paper treatment agent to the paper with a roller equipped with a metal cylinder with a plate made on its surface. In the spray method, the paper treatment agent is sprayed in a mist form from a nozzle using compressed air. In the rotor dampening method, the paper treatment agent is sprayed in a mist form onto the paper with a disk rotating at high speed.

The amount of the paper treatment agent applied to the paper is preferably 1 to 7 g/m ² , more preferably 1.5 to 6 g/m ² , in terms of the effective amount excluding moisture.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.
(1) Preparation of Paper Treatment Agent A paper treatment agent was prepared according to the following procedure.
The raw materials were charged in the amounts shown in Tables 1 and 2 into a beaker and mixed under stirring at a temperature at which each raw material dissolved to prepare a paper treatment agent. The amount of each component shown in Table 1 indicates the effective amount excluding water when the actual amount contains water.

(2) Preparation of Coated Paper The paper treatment agents obtained above were dissolved in water to prepare treatment solutions with an active content of 25% by mass. Each treatment solution was sprayed evenly onto both sides of a dry tissue (ply count 2, basis weight 12-13 g/ ^m2 ) so that the active content of the treatment agent was 25% by mass ±3%, and then the tissue was air-dried for 3 hours.

(3) Evaluation The coated papers of the Examples and Comparative Examples prepared above were evaluated as follows.
[40% RH, 25°C equilibrium moisture content (%), 25% by weight coated paper]
As a standard low humidity environment for winter, an environment of 40% RH and 25°C was created. The masses of 10 sheets (5 sets) of coated paper prepared at regular intervals were measured, and when there was no more change in mass, it was determined that the moisture content had reached equilibrium. The bone dry masses of the coated paper and base paper were taken as the masses after drying at 80°C for 90 minutes.
Moisture content at equilibrium (%)=(mass at equilibrium (g)−bone dry mass of coated paper (g))/bone dry mass of base paper (g)

[Flexibility and moist feeling at low humidity (B value)]
The coated papers were prepared by the same procedure as above, after conditioning at a humidity of 40% RH and 25°C. A pure bending tester KES-FB2-S (Kato Tech Co., Ltd.) was used as the testing equipment to determine the B value, which indicates the bending softness of two sheets of the coated papers (one set).
Evaluation criteria: ⊚: B value is less than 0.06; ◯+: B value is 0.06 or more and less than 0.065; ◯: B value is 0.065 or more and less than 0.07; ×: B value is 0.07 or more

[Softness and moist feeling at low humidity (sensory evaluation)]
For the sensory evaluation, coated papers prepared by the same procedure as above, after conditioning at a humidity of 40% RH and 25°C, were evaluated by 10 experienced panelists on a scale of 1 to 3 based on the following evaluation points, and the average value was used to evaluate the papers according to the following criteria.
Evaluation score: 3 points: Feels soft and moist.
2 points: Feels somewhat flexible and moist.
1 point: Neither felt.
Evaluation criteria: ◎: The average score of the 10 panelists is 2.5 points or more. ◯+: The average score of the 10 panelists is 2.0 points or more and less than 2.5 points. ○: The average score of the 10 panelists is 1.5 points or more and less than 2.0 points. ×: The average score of the 10 panelists is less than 1.5 points.

[Stability of treatment agent]
The condition of the treatment agents prepared in each of the Examples and Comparative Examples in (1) was checked immediately after preparation and after being left to stand at room temperature for one month, and evaluated according to the following criteria, taking into consideration suitability for practical use.
Evaluation criteria: ◎: Maintains a uniform state immediately after preparation and one month later. 〇+: Maintains a uniform state one month later, although there is a slight change in state (viscosity and appearance). 〇: Maintains a uniform state one month later, although there is a slight change in state. ×: Not uniform immediately after preparation, or does not maintain a uniform state for one month.

[Viscosity of treatment agent]
The viscosity of the treatment agents prepared in each of the Examples and Comparative Examples in (1) was measured at 60 rpm and 40° C. using a Brookfield viscometer, and the viscosity was evaluated according to the following criteria, taking into account the operability.
Evaluation criteria: ◎: Viscosity of the treatment agent is less than 800 mPa·s; ◯+: Viscosity of the treatment agent is 800 mPa·s or more and less than 1500 mPa·s; ○: Viscosity of the treatment agent is 1500 mPa·s or more and less than 2000 mPa·s; ×: Viscosity of the treatment agent is 2000 mPa·s or more or cannot be measured (unable to maintain a uniform state)

The formulations of the examples and comparative examples and the evaluation results of each item are shown in Tables 1 and 2. In Tables 1 and 2, the formulation amount of each component is shown in parts by mass.
In the evaluation items in Tables 1 and 2, ◎, ○+, and ○ are in a desirable range in terms of solving the problem, and there is a significant difference in the effect between them. × means that if even one of the items is included, it is judged that it is impossible to solve the problem.
In Tables 1 and 2, the HLB values of components (C) and (C') are shown in the same tables.

From Tables 1 and 2, in Examples 1 to 17, a paper treatment agent was used that contains (A) a polyhydric alcohol as the main component, (B) a water-containing oil component in a specific range of amounts, and (C) a nonionic surfactant with an HLB of 12 or more. These give the paper flexibility and a moist feel, and can reduce the deterioration of the texture of the treated paper due to a decrease in moisture caused by the humidity environment. Furthermore, the paper treatment agent has good stability over time and can maintain an appropriate viscosity. In the evaluation of the Examples and Comparative Examples, the sensory evaluation was rated as ◎ when the moisture content was 4.5% or more as an objective index, 〇+ when it was 4.4%, 〇 when it was 4.2%, and × when it was 4.1% or less, confirming that there is a high correlation between the moisture content of the coated paper and the sensory evaluation. Regarding the texture, it was also confirmed that there is a high correlation between the B value as an objective index using a test device and the sensory evaluation in the evaluation of the Examples and Comparative Examples. It was confirmed that the effect tends to be more pronounced when the content of the (C) component is within a specific range, when the mass ratio ((B)/(C)) of the (B) component to the (C) component is within a specific range, or when a nonionic surfactant (C') with an HLB of less than 12 is contained and the mass ratio ((C')/(C)) of the (C') component to the (C) component is within a specific range. Comparative Examples 1 and 4 contained a small amount of the (B) component, and Comparative Example 7 did not contain the (B) component, but even when paraffin, an oily component that does not have water-holding capacity, was added as in Comparative Examples 4 and 7, the desired effects such as flexibility at low humidity and moist feeling were not obtained. Comparative Example 8 contained a large amount of the (B) component, and the emulsion could not be stably emulsified and the viscosity was high. Comparative Examples 6 and 9 used other surfactants instead of the (C) component, but the emulsion could not be stably emulsified and the viscosity was high. Comparative Examples 2, 3, and 5 were formulations that did not primarily contain component (A), such as those that contained a large amount of oily components, and formulations that used components such as nonionic surfactants with an HLB of less than 12, higher fatty acids, higher alcohols, and organic acids, but did not achieve the desired effect.

Claims (6)

(A) A paper treatment agent containing a polyhydric alcohol as a main component,
A paper treatment agent comprising (B) at least one water-containing oil component selected from petrolatum, lanolin, an ester compound of a fatty acid including a dimer acid and a polyhydric alcohol, lanolin alcohol, and lanolin fatty acid, in an amount of 0.40 to 25 mass% based on the total amount of the treatment agent excluding water, and (C) a nonionic surfactant having an HLB of 12 or more. The paper treatment agent according to claim 1, wherein the content of the component (C) is 0.1 to 40% by mass based on the total amount of the treatment agent excluding water. The paper treatment agent according to claim 1 or 2, wherein the content of the (A) component is 80% by mass or more based on the total amount of the treatment agent excluding water, the content of the (B) component is 0.5 to 20% by mass based on the total amount of the treatment agent excluding water, and the content of the (C) component is 0.2 to 20% by mass based on the total amount of the treatment agent excluding water. The paper treatment agent according to any one of claims 1 to 3, wherein the mass ratio ((B)/(C)) of the (B) component to the (C) component is 0.005 to 99. The paper treatment agent according to any one of claims 1 to 4, which contains (C') a nonionic surfactant with an HLB of less than 12, and the mass ratio ((C')/(C)) of the (C') component to the (C) component is 0.01 to 10. Paper treated with the paper treatment agent according to any one of claims 1 to 5.