JP2864108B2 - Recycled paper manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing recycled paper using a paper product on which a resin film is bonded, such as a paper pack or a paper cup.

[0002]

2. Description of the Related Art In the case of recycling a paper product in which a resin film is bonded to paper, the resin film and the pulp fiber constituting the paper are conventionally separated, and only the pulp fiber component is used for the recycled paper. Was discarded or incinerated. However, when the resin film is discarded, it is hard to corrode and exists forever in the sea or underground, and there is a problem that fish and seabirds accidentally swallow it with seaweed and small animals or float as garbage. . In addition, when the resin film is incinerated, the amount of heat is high, so that the life of the incinerator is shortened.

[0003] Therefore, in paper products to which a resin film is bonded, it is considered that the resin film is contained in recycled paper. However , the resin film has a strong hydrophobicity, and thus simply forms a crushed resin film piece. Therefore, even if it is put into water, if it is left standing, it will rise and it will be difficult to disperse it easily in water, making paper making difficult. In addition, in the case of containing a resin film, the fine powder of the resin film contained in the wet sheet after paper making falls off, and in the drying step, the fine powder of the resin film is heat-fused to the surface of the dryer, and is regenerated after drying. The paper is perforated. If the paper is perforated in this way, the commercial value of the paper will be reduced. Further, even if a paper containing a resin film could be made, the resin film portion was hydrophobic, so that the receptivity of the water-soluble ink was inferior and a repelling phenomenon occurred, so that the paper could not be used as writing paper.

As a method for compensating for these disadvantages, Japanese Patent Laid-Open Publication No. Hei.
No. 269200 has been proposed. In this method, the heat-fusible resin to which the resin film adheres is finely pulverized without separation and removal to obtain a papermaking raw material, and a chemical fiber base is added to the papermaking raw material, and the resultant is aggregated and laminated with a cationic polymer flocculant. , Further adding auxiliary fiber material, pulp fiber,
This is a method of making paper by covering with a flocculant, a hydrophobizing agent or the like (hereinafter referred to as a resin film encapsulation method).

[0005]

However, the resin film encapsulation method requires a long and complicated manufacturing process,
Manufacturing management was difficult. According to the present invention, although a resin film is included, no perforation occurs during production, and not only the acceptability of the water-soluble ink is improved, but also the resin film is appropriately scattered and has an excellent appearance. Another object of the present invention is to provide a method for producing recycled paper that is excellent in terms of quality.

[0006]

Means for Solving the Problems The inventors of the present application have:
The present invention was completed by focusing on the fact that if the resin film becomes hydrophilic, all the drawbacks of the recycled paper containing the conventional resin film can be eliminated.

That is, according to the method for producing recycled paper of the present invention, a paper product to which a resin film is bonded is separated into a paper and a resin film, and the separated resin film is separated by 0.1%.
The cut resin film is subjected to a hydrophilic treatment with a hydrophilic treating agent, and the separated paper is beaten into paper pulp fibers, and auxiliary fibers are added to the hydrophilic treated resin film and paper pulp fibers. Paper making.

In the method for producing recycled paper according to the present invention, a paperwork product having a resin film bonded thereto is put into a pulp disintegrator, immersed in hot water or warm water and stirred, and the resin film and the fiber content of the paper are separated. To separate. The separated resin film is taken out, dried, collected, cut, and given hydrophilicity with a hydrophilic treating agent (hereinafter, simply referred to as a treating agent) to be used as one papermaking raw material. Is used together with other auxiliary fibers as the other papermaking raw material.

[0009] In addition to the separated resin film,
On a large amount to another resin film Lum waste also cut to exist on the market
It can be used as described above . These resin films are cut into pieces of about 0.1 to 10 mm, preferably about 5 mm without pulverization, and are subjected to hydrophilic treatment with a treating agent. ) To (E).

(A) 0.3 to 8% by weight of a divalent to tetravalent metal salt (B) Aromatic or aliphatic isocyanate terminated with a polyalkylene oxide polyol having 2 to 6 functional groups. 1 to 8% by weight (C) 0.3 to 35% by weight of a surfactant (D) 0.1 to 60% by weight of a water-soluble polyurethane or a water-dispersible polyurethane (E) The remainder has 2 to 6 functional groups. Having polyalkylene oxide polyol

The divalent to tetravalent metal salt of the component (A) is a salt of a metal and an inorganic or organic acid. Examples of such metal salts include salts of divalent metals such as zinc salts, calcium salts and magnesium salts, salts of trivalent metals such as aluminum salts, chromium salts and cerium salts, and salts of zirconium salts and silicon salts.
Salts of a valent metal can be mentioned. Among them, aluminum salts and zirconium salts are preferred.

Examples of the aluminum salt include aluminum sulfate, aluminum acetate, aluminum chloride, and aluminum lactate. Examples of the zirconium salt include zirconium sulfate. Of these metal salts, a trivalent metal salt is preferably used. Is done. Two or more of these divalent to tetravalent metal salts can be used in combination.

The component (A) is from 0.3 to 8% by weight based on the total amount of the treating agent.
Adhesion to the resin film becomes inferior, and when it exceeds 8% by weight, it is too much and the stability of the treating agent becomes inferior.

As the aromatic or aliphatic isocyanate terminal-treated with the polyalkylene oxide polyol having 2 to 6 functional groups of the component (B), a large excess of aromatic or aliphatic isocyanate is used. By reacting with a polyalkylene oxide polyol having a plurality of functional groups, and protecting the terminal isocyanate group with a polyol.

Examples of the aromatic or aliphatic isocyanate include tolylene diisocyanate, 4-4'-diphenylmethane diisocyanate, phenylene diisocyanate, naphthalene 1.5 diisocyanate, polymethylene polyphenyl polyisocyanate, xylene diisocyanate, and trimethylolpropane. Tolylene diisocyanate, hydrogenated xylene diisocyanate, isophorone diisocyanate, and poly-hexamethylene diisocyanate.

Of these, polymethylene polyphenyl polyisocyanate and polyhexamethylene diisocyanate (including biuret type and isocyanurate type) are preferred. On the other hand, polyalkylene oxide polyols having 2 to 4 functional groups include (E)
Polyalkylene oxide polyols having 2 to 6 functional groups as components are used. Each of these may be used in combination of two or more.

As the surfactant of the component (C), a nonionic surfactant, an anionic surfactant and a double-sided surfactant are used, and two or more of these may be used in combination. Among these, nonionic surfactants include (a) polyoxyethylene alkyl phenyl ether, polyoxypropylene alkyl ether, which has an alkyl group having 6 to 12 carbon atoms and to which 1 to 20 mol of ethylene oxide is added. Oxyethylene polyoxypropylene alkyl ether, higher fatty acid alkanolamide,
Or an ethylene oxide adduct thereof, a sucrose fatty acid ester, an alkyl saccharide, a fatty acid glycerin monoester, (b) a linear or branched alkyl or alkenyl group having an average of 10 to 20 carbon atoms, and 1 to 20 mol And polyoxyethylene alkyl or alkenyl ether to which ethylene oxide is added.

Examples of the anionic surfactant include: (a) an alkali metal salt of a higher fatty acid (soap); and (b) a linear or branched alkyl or alkenyl group having an average of 10 to 20 carbon atoms. Within 0.
(C) an alkylbenzene sulfonate having an alkyl group having an average carbon number of 10 to 16; and (d) an alkyl group or an alkenyl group having an average carbon number of 10 to 20. (E) Olefin sulfonic acid having an average of 10 to 20 carbon atoms in one molecule (f) Alkane sulfonate having an average of 10 to 20 carbon atoms in the molecule (g) Sulfosuccinate Sodium salt (h) ether carboxylic acid (i) monoalkyl phosphate and the like.

Examples of the double-sided surfactant include (a) an alkyl betaine type and (b) an amido betaine type.

As such a surfactant, a nonionic surfactant is suitable, and in particular, an ethylene oxide adduct to an alkylphenol is preferable. The number of carbon atoms of the alkyl group of the alkylphenol is preferably 7 to 10, and the number of moles of ethylene oxide added is 4 to 11, preferably 6 to 9.

The amount of the component (C) is from 0.3 to 35.
However, if the amount is less than 0.3% by weight, the dispersibility of the treating agent in water will be poor. Also, 35
If the amount is more than the weight%, the effect of adhering to the resin film decreases.

The water-soluble polyurethane or the water-dispersible polyurethane of the component (D) is as follows: (a) As a non-reactive water-soluble polyurethane, a polyurethane resin obtained by reacting a diisocyanate with a polyol containing a large amount of ethylene oxide. Water dispersion type (emulsion) non-reactive, forced emulsification type polyurethane resin (c) Water dispersion type (emulsion) non-reaction type, self-emulsification type polyurethane resin (d) Reaction type water-soluble or water dispersible (emulsion) forced emulsification type Or a self-emulsifying polyurethane resin or the like, and these may be used alone or in combination of two or more. If the amount is less than 0.1% by weight, adhesion to a resin film is reduced, and If it exceeds 60% by weight, the hydrophilicity decreases.

Component (E), a polyalkylene oxide polyol having 2 to 6 functional groups, is a main raw material of the treating agent, and is preferably a polyalkylene oxide polyol having 2 to 3 functional groups. It contains. The molecular weight of such a polyalkylene oxide polyol is 6
00 to 10,000, preferably 2,000 to 6,000
0.

As the starting alkylene oxide, ethylene oxide, propylene oxide, 1-2 or 2.3
-Butylene oxide and the like, and combinations of two or more thereof.

Specific examples of the polyalkylene oxide polyol include polypropylene oxide-trithymethylolpropanetriol, polypropylene oxide-
Hexanetriol, polypropylene oxide-glycerin triol, random or block copolymerized propylene oxide / ethylene oxide-glycerin triol, random or block copolymerized propylene oxide / ethylene oxide-ethylenediaminetetraol, polypropylene oxide-sorbitol hexanetriol and the like can be mentioned.

These polyalkylene oxide polyols may be used in combination of two or more. The most preferred polyalkylene oxide polyol is a random copolymerized polyethylene oxide / propylene oxide polyol (preferably about 70% by weight ethylene oxide).

This treating agent may contain, in addition to the components (A) to (E), other additives as needed, as long as the performance of the treating agent is not reduced. Such additives include binder resins, dyeing aids, colorants, PH
And the like.

The method for producing this treating agent is described in the above (A) to (E).
May be added and mixed in an appropriate order, but preferably performed as follows. Large excess of component (E) 2-6
An aromatic or aliphatic isocyanate is added to and mixed with a polyalkylene oxide polyol having two functional groups. Then, the component (B) is generated when the component (E) is mixed with an isocyanate or the like that has been terminally treated with a polyalkylene oxide. Next, an aqueous solution of a divalent to tetravalent metal salt as the component (A) is added, and then a surfactant as the component (C) is added and stirred. Finally, a water-soluble polyurethane or a water-dispersible polyurethane as the component (D) is added to generate a treating agent.

The above-mentioned treating agent contains each of the components (A) to (E) as essential components. The water-soluble polyurethane or the water-dispersible polyurethane as the component (D) and the components 2 to 4 of the component (A) are used. For compounding a valent metal salt in the form of an aqueous solution,
Water may be appropriately contained. This moisture is (A) ~
It is preferably at least 10 parts by weight per 100 parts by weight of each component of (E), and the pH in this case is suitably from 5 to 8, preferably from 6 to 7.5.

When the resin film is treated with the above treating agent, the treating agent is used in an amount of 1 to 10% by weight, preferably 2 to 5% by weight, based on the dry weight of the resin film. About 10 to facilitate processing
It is preferable to appropriately dilute with up to 300 times the amount of water before use.

When the amount of the water-soluble polyurethane or the water-dispersible polyurethane resin as the component (D) is increased, the resin adheres well to the resin film to be treated.

If the resin film is not treated with the above-mentioned treating agent, the resin film falls off from the wet sheet when the wet sheet after the paper making is passed through a dryer so that the resin film is finely pulverized, and the resin film falls on the surface of the dryer. Heat fusion,
After drying, the paper is perforated and its commercial value is reduced.

When the amount of the resin film treated with this treating agent is less than 0.5% by weight in the production of recycled paper, the obtained dispersed paper has a reduced color scattered amount and an aesthetic effect appears. Absent. On the other hand, if the content exceeds 15% by weight, the color density becomes high, and when printed on recycled paper, there arises a problem that the printed ink becomes difficult to see clearly.

The auxiliary fibers used in conjunction with paper after separation of the resin film from the Paper converting products, chemical fiber, those plant fibers, of more than one selected from the leather fibers, the chemical fibers, synthetic fibers, inorganic Fiber, cellulose fiber, etc.
Vegetable fibers are wood pulp and bast fiber, and these chemical fibers, vegetable fibers, and leather fibers are 0.5 to 10 mm in length.
Used to be crushed. In this case, the auxiliary fibers which could not be used as a papermaking raw material because they simply floated without being dispersed in water by merely pulverizing may be given a hydrophilicity with the same treating agent as described above and used as a papermaking raw material. it can.

For example, leather fibers as auxiliary fibers are:
Unless the hydrophilicity-imparting treatment is carried out, the paper cannot be formed without being dispersed in water and cannot be paper-made. Therefore, preferably, when the resin film is treated with the treating agent, the fine powder of the leather fiber is added, and the hydrophilicity is simultaneously increased. By applying, an aspect ratio (ratio of thickness to length) of 1:50 or more is changed to 3
When 0% by weight or more is mixed with the separated paper, the obtained recycled paper has significantly improved bending strength and increased flame retardancy. These auxiliary fibers may be of only one type,
A mixture of more than one kind can be used. If the amount of the auxiliary fiber is less than 0.5% by weight, the strength is low, and if it is more than 60% by weight, there is no particular effect. These auxiliary fibers can be made by changing the type and composition according to the properties (strength, texture, moisture absorption, air permeability, smoothness, elongation, etc.) of the paper after papermaking.

As a method of blending a finely pulverized resin film, a method is disclosed in the above-mentioned JP-A-3-269200, but the production method of the present invention does not require such a multi-step process. 5mm peeling resin film
It is cut around the corner, treated with the treatment agent and mixed. When the resin film is cut into approximately 5 mm squares by a cutting machine such as a shredder and mixed, the resin film is sandwiched between the fibers of the wet sheet, and even if it touches the dryer surface partially, the wet sheet surface And does not adhere to the dryer surface due to heat fusion. Recycled paper obtained by blending the resin film obtained in this way has high smoothness, no perforations and high commercial value.

For papermaking in the production of recycled paper, a conventional papermaking chemical is used. Further, as a binder fiber for fixing a fiber which does not become entangled with each other due to non-fibrillation such as a resin film or a leather fiber to a fiber portion of paper, cellulose binder fiber which has been conventionally used, rayon Papermaking can be performed by adding a system filament, a vinylon binder fiber, an acrylic binder fiber, or the like.

As the papermaking agent, for example, a rosin-based sizing agent, a wax-based sizing agent, a starch-based sizing agent, a synthetic resin-based sizing agent, or the like is used as a sizing agent. Sizing agents are suitable.

Acrylic amides, melamines, and the like are used as paper strength enhancers, and organic, fluorine, silicon, and the like are appropriately used as defoamers. Acrylics such as polyethylene oxide, polyalkylene oxide polyol, and acrylamide are used as the adhesive, and starch, methyl cellulose, carboxymethyl cellulose, polyvinyl alcohol,
Papermaking agents such as vinyl acetate and acrylic paste are appropriately compounded according to the intended use to make paper.

The binder fibers, sizing agent, sizing agent, defoaming agent, and paper strength enhancer were prepared while observing the conditions during papermaking.
Increase or decrease the amount of addition appropriately.

The paper products to which the resin film is attached are:
Put into a pulp disintegrator and stir in hot or warm water,
The resin film and pulp fiber are separated. Resin film separated is taken out dry, paper pulp fiber content was Tsu residue, at beater or a refiner by the addition of normal reproduction wastepaper pulp performs beating beating time 30 to 60 minutes at a concentration 4-5% by weight, The fibers are fibrillated and used as papermaking raw materials.

In consideration of the above-mentioned dried resin film and the color balance of the paper surface after papermaking (variation of the colored color film), the amount of debris colored in an insufficient color for the intended color distribution is considered. A resin film is added, and one piece is cut into 0.1 to 10 mm, preferably around 5 mm by a shredder or a cutting machine.
Warm water at about 0 ° C. and a treating agent for imparting hydrophilicity are added in an amount of 1 to 6% by weight based on the weight of the resin film, and the mixture is stirred to adhere the treating agent components to prepare a papermaking raw material. The amount of the resin film added during papermaking is 0.5 to 15% by weight. If the resin film is smaller than 0.1 mm or larger than 10 mm, the color balance will not be good.

The concentration in the papermaking tank (bat) during papermaking is usually 0.01 to 0.03% by weight, and the wire mesh of the papermaking mesh is 60 to 80 mesh. The surface temperature of the drying dryer is 110 - 140 ° C..

The surface gloss of the recycled paper after papermaking can be imparted to the surface gloss or matte depending on the mixing ratio of the compounding raw materials and the added chemicals. The preferred basis weight of the recycled paper after papermaking is as follows. Usually, it is 10 to 300 g / m ² .

[0045]

In the method for producing recycled paper according to the present invention, a paper product on which a resin film is bonded is separated into a paper and a resin film, and the separated resin film is cut into a size of about 1 to 10 mm and treated with a treating agent. When treated to impart hydrophilicity and paper-making the paper together with the separated paper and auxiliary fibers, the resin film is scattered on the recycled paper to improve the color balance and improve the aesthetic effect. In addition, by imparting hydrophilicity to the resin film, the resin film does not adhere to the dryer at the time of drying and does not form a hole, and the acceptability of the water-soluble ink is improved.

[0046]

EXAMPLES Hereinafter, the method for producing recycled paper of the present invention will be described in more detail with reference to examples. <Example 1> Paper packs such as a milk pack, a sake pack, and a juice pack each having a resin film attached thereto were put into a pulp disintegrator.
After being immersed in warm water of 50 ° C. or higher, steam was blown in and stirred to separate the resin film and the paper pulp fiber component. The resin film was separated by filtration and dried in the sun. In consideration of the color balance of the resin film and the paper surface after papermaking, mix a color film of debris colored with a color that is insufficient for the intended color distribution, and pass through a shredder two or three times. After cutting so that the average of one piece was 2 to 7 mm, 40 kg was weighed.

Next, in order to impart hydrophilicity to the resin film, 1.2 kg of the treating agent was added to 100 liters of 30 ° C. warm water.
Was cut into a liquid in which was dispersed and dispersed. After stirring for about 30 minutes, this was taken out and used as a papermaking raw material.

On the other hand, a recycled waste paper pulp raw material was added to paper fibers having a fiber length of 0.1 to 5 mm separated from the resin film and added to a pulper and a beater. At that time, disintegration and beating were performed at a concentration of 4 to 5% by weight for 45 minutes to obtain a fiber paper raw material.

7500 liters of water was added to a pulper having a capacity of 8 m ³ , 390 kg of the recycled paper pulp fiber raw material (dry amount),
Resin film provided with the above hydrophilicity (in terms of dry weight) 40
kg, vinylon binder 20k with fiber length 1-4mm
g, 2 liters of paper strength agent (acrylamide), 1 liter of sizing agent (rosin), 0.1 kg of defoaming agent (trade name: Alcox), 3 kg of paste (polyethylene glycol), and 8% of aluminum sulfate 4 liters of the aqueous solution was added and stirred for 30 minutes.

Next, this mixed solution was transferred to a stock tank, and water was added to a concentration of 2.5% by weight, and the mixture was stirred at a low speed so as not to precipitate. To this solution was added diluting water in which a paste (polyethylene oxide) was dissolved to a low concentration with circulating water of white water to a concentration of 0.02%, and the mixture was placed in a papermaking tank (bat). After a paper layer was formed using a papermaking cylinder wire mesh of 60 mesh, the paper layer was moved to a blanket, and then water was dehydrated by suction. Thereafter, the paper was further dehydrated through a press roll, transferred to a drying drier (temperature: 120 ° C.), and dried to obtain recycled paper mixed with a resin film. The product basis weight at this time is 70 g / m ² , 85 g / m ² , 130 g / m ²
is a three types of m ^2. Table 1 shows the properties of the obtained recycled paper.

The treating agent was prepared by the following method. [Preparation of Treatment Agent] Polyoxyethylene polyoxypropylene triol (manufactured by Sanyo Chemical Co., Ltd .: Sannics FA103) 86
To 1 g, 25 g of hexamethylene diisocyanate and 300 g of an 8% aqueous solution of aluminum sulfate were added, and a nitrogen-containing polyol (manufactured by Sanyo Chemical Co., Ltd .: Sannics CA-20)
4) After adding 40 g, 50 g of a surfactant polyoxyethylene nonylphenyl ether (manufactured by Sanyo Chemical Co., Ltd .: Nonipol 80) was added and mixed to form a uniform solution.
In addition, water-soluble non-reactive polyurethane (solid content 30%) 1
50 g was added and stirred to obtain a treating agent.

<Example 2> A paper was made in the same manner as in Example 1 except that the treating agent prepared in Example 1 was used and the raw materials for papermaking were changed. 2.3 kg of the resin film provided with hydrophilicity (in terms of dry), 230 kg of fine leather fiber powder provided with hydrophilicity (in terms of dry), and 190 kg of recycled paper pulp fiber raw material (dry amount). Table 1 shows the properties of the obtained recycled paper.

<Example 3> Papermaking was carried out in the same manner as in Example 1 except that the raw materials for papermaking in Example 1 were changed as follows. 16 kg of resin film (dry equivalent) provided with hydrophilicity, 200 kg of recycled paper pulp fiber raw material (dry amount), 110 kg of wood pulp (dry amount),
100 kg of plant fiber (moon peach fiber). Table 1 shows the properties of the obtained recycled paper.

The treating agent used in Example 3 was prepared as follows. [Preparation of treating agent] Water-dispersible polyurethane resin (manufactured by Toagosei Co., Ltd .: Neotan UE) with respect to 70% by weight of the treating agent of Examples 1 and 2.
1300, 40% solids) was added at 30% by weight and stirred to obtain a treating agent.

Comparative Example 1 Example 1 except that a resin film not subjected to a hydrophilic treatment was used.
The same papermaking was performed using the same raw materials. Table 1 shows the properties of the obtained recycled paper.

[0056]

The test methods described in Table 1 are as follows. Basis weight: JIS-P-8111-1976 Conforms to pretreatment of test paper Thickness: JIS-P-8118-1976 Conforms to test method for thickness and density of paper and paperboard Density: Same Tensile strength: JIS-P -8113-1976 Conforms to tensile strength test method for paper and paperboard Air permeability: conforms to JIS-P-8117-1980 Test method for paper and paperboard Water dispersibility during papermaking: Visual adhesion to dryer: Water-soluble ink acceptance by visual inspection: Visual inspection Perforation of paper surface: Visual inspection

[0058]

According to the method for producing recycled paper of the present invention, a paper product on which a resin film is bonded is separated into paper and a resin film, and the separated resin film is cut into a required size and treated with a treating agent. To impart hydrophilicity, and to make paper together with the separated paper and auxiliary fibers.Since the production process is short, not only is production management easy, but also the treatment agent adheres to the surface of the resin film. Therefore, the resin value does not adhere to the dryer at the time of drying after papermaking, thereby preventing the paper from being perforated, thereby increasing the commercial value of the recycled paper.

The recycled paper obtained by this manufacturing method is excellent in receptivity to water-soluble ink, so that it can be used as writing paper such as stationery and memo paper. Since the film is scattered and the color balance is good, it can be used as wallpaper, fusuma, or wrapping paper or colored paper that can be seen by humans. .

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-97798 (JP, A) JP-A-3-269200 (JP, A) JP-B-58-42319 (JP, B2) JP-B-39-39 23782 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21H 27/02-27/42 D21H 15/00-15/12 D21H 11/00-11/22

Claims (5)

(57) [Claims] 1. A paper product to which a resin film is attached
Separated into paper and a resin film , the separated resin film is cut into 0.1 to 10 mm, and the cut resin film is subjected to a hydrophilic treatment with a hydrophilic treatment agent. A method for producing recycled paper, comprising making a paper by adding auxiliary fibers to a resin film and paper pulp fibers which have been beaten and subjected to a hydrophilic treatment. 2. The method according to claim 1, wherein the hydrophilic treating agent comprises:
The method for producing recycled paper according to claim 1, wherein the method comprises (E). (A) 0.3 to 8% by weight of a divalent to tetravalent metal salt (B) 0.1 to 8 of an aromatic or aliphatic isocyanate terminated with a polyalkylene oxide polyol having 2 to 6 functional groups (C) 0.3 to 35% by weight of a surfactant (D) 0.1 to 60% by weight of a water-soluble polyurethane or a water-dispersible polyurethane (E) Polyalkylene having a balance of 2 to 6 functional groups Oxide polyol 3. The method according to claim 1, wherein the auxiliary fiber is a chemical fiber, a vegetable fiber,
2. The method for producing recycled paper according to claim 1, wherein the method is at least one selected from leather fibers. 4. The papermaking machine according to claim 1, wherein the resin film after the hydrophilic treatment is 0.5 to 15% by weight, the auxiliary fiber is 0.5 to 60% by weight, and the remaining amount is the paper pulp fiber.
The method for producing recycled paper according to the above. 5. The method for producing recycled paper according to claim 1, wherein the auxiliary fibers have been subjected to a hydrophilic treatment with the hydrophilic treating agent.