JPH11293124A - Waste paper material for compounding in resin, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a waste paper material with excellent dispersibility and molding processability, and useful as e.g. a filler by treating a mixture comprising waste paper and a thermoplastic resin in specific proportions under specified conditions to convert the waste paper fiber into short fiber at a low treatment cost so that the bulk specific gravity of the final material fall within a specified range. SOLUTION: This waste paper material for compounding in resins is obtained by heat treatment of a mixture comprising 100 pts.wt. of waste paper and 15-70 pts.wt. of a thermoplastic resin such as polyethylene using a high-speed mixer at the circumferential speed of the mixer blade tip of 5-35 m/s and a kneading temperature of 215-280 deg.C so as to thermally decompose the waste paper so that the bulk specific gravity of the final material comes to 0.15-0.60. Besides, it is preferable that the material obtained above is granulated using a non-screw type compressive granulator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an existing extrusion molding method, in which when waste paper is compounded in a thermoplastic resin as a filler, the waste paper fiber exhibits good dispersibility in the thermoplastic resin. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a used paper material for resin blending having excellent moldability such as injection molding and inflation molding and a method for producing the same.

[0002]

2. Description of the Related Art It is generally known to combine waste paper with a thermoplastic resin for the purpose of modifying and increasing the amount of waste paper. Many of the prior arts involve kneading waste paper pulverized into fine powder or small pieces into a thermoplastic resin which is melted by heat.

[0003]

SUMMARY OF THE INVENTION Cutter mill crushing [5
-10 mm square] or using waste paper defibrated or crushed by a turbo mill, and kneaded in a thermoplastic resin by a kneader such as an existing extruder or kneader. Power load is also large. In particular, a sufficient kneading action cannot be given due to a heat generation problem due to a power overload, and the used paper is easily maintained in the shape at the time of preparation, and exists in the thermoplastic resin in a state of poor dispersion of the used paper or in a long fiber state.
Especially, even if you try high blending of waste paper in such a state,
The poor dispersion of the waste paper causes poor flow during thermal melting. If a high amount of used paper is forcibly mixed, the productivity will decrease due to an increase in mechanical load and heat generation in the cylinder in the product processing stages such as extrusion molding and injection molding. For example, injection molding causes defects in molded products such as short shots, burns, sink marks, weld line strength, and flow marks.

[0004] In order to solve these problems, there is a method in which a screen of about 100 mesh is passed by a crusher to obtain crushed waste paper. However, waste paper is limited, and at present it is economically difficult to reuse it in papermaking equipment, so waste paper that has been incinerated with a thermoplastic resin film or waste paper impregnated with thermoplastic resin generates heat due to pulverization. Therefore, the resin is fused to the screen and causes clogging, which is not applicable. Also, even if the used paper other than these passes 100 mesh, the used paper fiber has an average length of 0.2 to 0.35 m.
m, a mixture of L material and N material having a width of 10 to 60 μm. This shape is a common filler such as calcium carbonate,
It is considerably larger than talc. In fact, 10
The kneading composition in which the used paper with a mesh ratio of 50% by weight is obtained by using a kneader or a high-speed mixer with the used paper of a 0 mesh pass using a kneader or a high-speed mixer is inferior in the heat-melt fluidity and causes the above-mentioned molding trouble.

[0005] Further, even if an attempt is made to perform fine pulverization using a pulverizer to pass a screen of 100 mesh or more, production efficiency is remarkably reduced due to overload of equipment power and breakage of the screen, and it is not economical. For this reason, in order to further obtain finely pulverized waste paper, there is also a means of classifying a pulverized material of 100 mesh pass waste paper into 200 to 400 mesh after the pulverization step. But,
This is also inefficient and results in very expensive finely ground waste paper. As described above, the fine pulverization of the used paper has a problem that it is difficult to obtain a pulverized product having a desired particle size at a low cost because the used paper is limited and the cellulose fiber is flexible.

The present invention overcomes the drawbacks of the prior art and reduces the waste paper fiber at low processing cost, thereby improving the dispersibility and molding processability of the recycled paper material for resin blending, and a method for producing the same. The purpose is to provide.

[0007]

SUMMARY OF THE INVENTION In the present invention, an attempt was made to solve the above-mentioned prior art by pulverizing used paper under appropriate conditions. The present inventors have conducted various studies on inexpensive and efficient pulverization of waste paper, and as a result,
It has been found that the above-mentioned object can be achieved by giving a thermomechanical effect to waste paper, and the present invention has been completed based on this finding.

The waste paper material for resin blending according to the present invention is a mixture containing 100 parts by weight of waste paper and 15 to 70 parts by weight of a thermoplastic resin, and the waste paper in the mixture is thermally decomposed to form a fine powder. , And the overall bulk specific gravity is 0.15 to 0.60. Further, the waste paper material for resin blending according to the present invention is formed in a granular shape.

The method for producing a used paper material for resin blending according to the present invention is characterized in that a mixture containing 100 parts by weight of used paper and 15 to 70 parts by weight of a thermoplastic resin is subjected to a heat treatment for thermally decomposing the used paper by a high-speed mixer. The specific gravity was 0.15 to 0.60.

In the method for producing a waste paper material for compounding a resin according to the present invention, the heat treatment can be easily carried out by using the following conditions and methods. That is, using a high-speed mixer, the peripheral speed at the tip of the mixer blade is 5 to 35 m.
/ S, a heat treatment at which the used paper is thermally decomposed at a kneading temperature of 215 to 280 ° C.

Further, in the method for producing a waste paper material for resin blending according to the present invention, the waste paper material for resin blending is granulated by a non-screw type compression granulator.

The waste paper used in the present invention is a surface or middle layer of scraps, office automation waste paper (OA waste paper), newspaper waste paper, magazines, cardboard, and thermoplastic resin, which are generated when the dimensions of the formed paper are adjusted. There are laminated paper, resin-impregnated paper and the like. Of these, waste polyethylene laminated kraft paper that is currently incinerated is preferred. These waste paper forms need to be crushed or defibrated or pulverized without being entangled, and may be small pieces or punched scraps of several mm square as long as they are not entangled with each other. Also, used paper obtained by drying or dewatering the paper material extracted in the paper making process can be used.

The thermoplastic resin is not particularly limited as long as it can improve the effect of dispersing and reducing the volume of waste paper. General olefinic thermoplastic resins are particularly advantageous in terms of price.
The above-mentioned waste paper is bulky and has a low specific gravity, so that a resin having a large effect of reducing the waste paper volume by hot melting is more advantageous. Examples of such a resin are polyethylene, polypropylene, ethylene-based copolymer, and propylene-based copolymer. ,polystyrene,
Examples include acrylonitrile-styrene, acrylonitrile-butadiene-styrene copolymer, polyethylene-terephthalate, and various biodegradable resins having thermoplasticity. Further, those having a reactive group or a polar group having a high affinity for cellulose fibers are also effective. For example, a high-flow polyolefin resin, polyvinyl alcohol, ethylene-
Examples include a vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, polyvinyl butyral, and various modified polyolefins. One of these resins may be used,
Two or more kinds may be used.

Next, the thermoplastic resin ratio is 15 to 70 parts by weight of the thermoplastic resin with respect to 100 parts by weight of the waste paper.
As for the mixing ratio of the thermoplastic resin, the effect of reducing the volume of waste paper fibers by melting the resin, the load on the equipment and the accompanying heat generation, and the effect of increasing the temperature when using equipment that raises the temperature by frictional heat must be obtained efficiently. Is desirable. For example, when a high-speed mixer is used, if the blending ratio of the thermoplastic resin is too small, it is not possible to efficiently raise the temperature by frictional heat, which is not preferable in terms of production. If the blending ratio is out of this range, the gelled and molten resin completely covers the surface of the waste paper raw material, and the fusion of the mixture becomes severe, so that the heat treatment of the waste paper cannot be continued due to an overload of equipment power. As an example, FIG. 1 shows the relationship between the ratio of the thermoplastic resin to the waste paper and the mixer kneading time indicating the productivity.

Next, the waste paper material for resin blending after the heat treatment must have a bulk specific gravity of 0.15 to 0.60, more preferably 0.30 to improve productivity and workability in the next step. That is all. If the resin-mixed waste paper material after the heat treatment is bulky, the existing screw extruder will drop into the hopper, causing poor penetration into the screw and poor productivity and waste paper kneading properties, so it will be produced using a non-screw type compression granulator. In terms of surface, it is possible to perform the volume reduction process advantageously.

In the waste paper heating process using the high-speed mixer according to the present invention, the peripheral speed at the tip of the mixer blade is 5 to 35.
m / s, but if the purpose is to raise the temperature at the beginning of mixing,
A high peripheral speed of 5 m / s or more is desirable from the viewpoint of production efficiency. These adjust the peripheral speed of the blade according to the temperature of the mixture, the mixing ratio of the thermoplastic resin, and the power load of the high-speed mixer accompanying the gelation.

In the heat treatment using the high-speed mixer according to the present invention, the heat treatment must be performed at a mixing temperature of 215 to 280 ° C. If the temperature is lower than the lower limit of this temperature range, the effect of dispersing the used paper by the high-speed mixer is difficult to obtain, as will be shown in the examples below. Further, it is difficult to obtain the effect of reducing the volume of the mixture, which causes a decrease in productivity in the subsequent steps. The relationship with the bulk specific gravity of each kneaded material under these temperature conditions is as shown in FIG. When the used paper is heated in a high-speed mixer, smoke is generated from a temperature around 215 ° C., and acidic decomposition gas is recognized in PH test paper. Waste paper fiber is 2
If the temperature is higher than 50 ° C., discoloration and fuming become intense, the weight is rapidly lost, and the economic benefit is easily reduced. Therefore, temperature control is the most important. If the temperature is increased, hemicellulose is decomposed in waste paper, the molecular weight of cellulose is reduced, and the thermoplastic resin is oxidized and deteriorated. From this, a more desirable condition is specifically described. The heat treatment temperature is 215 to 250 ° C.

According to the present invention, various additives to be added to the conventional resin composition can be added to the extent that the effects of the present invention are not impaired, depending on the purpose of use. Agents, antioxidants, basic substances, coloring agents,
And antistatic agents. The basic substance has a function of neutralizing the acid gas, and includes inorganic powders such as sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, calcium hydroxide, calcium oxide, zinc oxide and sodium oxide, as well as triethanolamine and monoethanol. Examples thereof include amines such as ethanolamine and aniline.

[0019]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples. The dispersibility of waste paper cellulose fibers in the following Examples and Comparative Examples was evaluated by the following method. Evaluation method of waste paper fiber dispersibility The mixture obtained by kneading in Examples and Comparative Examples was mixed with polypropylene (G701, manufactured by Grand Polymer Co., Ltd., melt flow rate 0.1%) so that the cellulose fiber content was 7% by weight.
5, block copolymer], and using a Labo Plastomill 50MR type single screw extruder D2025 type [Toyo Seiki Seisakusho Co., Ltd. using full flight screw], 180
The mixture was extruded at 50 ° C. and pellets at 50 ° C. Next, 5 g of the pellet was immediately pressed at 180 ° C. and 100 kg /
cm ² for 3 minutes to obtain a thin sheet. This sheet was evaluated by light transmission on a scale of 1 to 4 based on the following criteria, and used as a method for evaluating dispersibility of used paper. ◎: good fiber dispersibility, ：: fibers are almost dispersed, Δ: some of the fibers are undispersed and bound, ×:
Most of the fibers are undispersed and remain bound or paper-like. Melt flow rate Conforms to JIS K6758 (230 ° C-2.16k
g).

EXAMPLE 1 A used newspaper was used to grind a CNDUX grinder CS cutter (3
using a square screen) to obtain roughly 3 mm square waste newspaper paper. 100 parts by weight of crushed used newspaper and polypropylene [J70 manufactured by Grand Polymer Co., Ltd.]
7, melt flow rate 23 g / 10 minutes, block copolymer] 45 parts by weight of Henschel mixer FM-
2025 type [Mitsui Mining Co., Ltd.] has 1225 waste paper
g at a ratio of up to 230 ° C. and heated and kneaded to 230 ° C. to obtain a used paper material for resin blending. The fiber dispersibility is shown in Table 1.

Example 2 The same waste newspaper and polypropylene as in Example 1 were used, and the mixture was heated and stirred and kneaded at 280 ° C. using a Henschel mixer FM-20B at the same blending ratio as in Example 1. The fiber dispersibility is shown in Table 1.

Example 3 100 parts by weight of used newspaper paper as in Example 1 and 70 parts by weight of polypropylene as in Example 1 were mixed with a Henschel mixer FM.
Using a -20B type, a heating, stirring and kneading treatment was performed up to 230 ° C. The fiber dispersibility is shown in Table 1.

Example 4 100 parts by weight of used newspaper paper as in Example 1 and 25 parts by weight of polypropylene as in Example 1 were mixed with a Henschel mixer FM.
Using a -20B type, a heating, stirring and kneading treatment was performed up to 230 ° C. The fiber dispersibility is shown in Table 1.

Example 5 The used newspaper of Example 1 was pulverized with a CS cutter (using 100 mesh screen) manufactured by CONDUX to obtain a used newspaper of 100 mesh pass. 100 parts by weight of used newspaper passed 100 mesh pass and 45 parts by weight of polypropylene [J107W manufactured by Grand Polymer Co., Ltd., melt flow rate 30, homopolymer] were heated and stirred and kneaded to 240 ° C. using a Henschel mixer. The fiber dispersibility is shown in Table 1.

Example 6 100 parts by weight of ground newspaper paper as in Example 5, 55 parts by weight of polypropylene as in Example 5, and 25 parts by weight of calcium carbonate [Shiraishi Kogyo Homocal-D] were mixed at 240 ° C. using a Henschel mixer. Until then, a heating, stirring and kneading process was performed. The fiber dispersibility is shown in Table 1.

Example 7 As in Example 1, 100 parts by weight of used newspaper and 45 parts by weight of a biodegradable resin [Bionole manufactured by Showa Polymer Co., Ltd.] were heated and stirred and kneaded to 240 ° C. using a Henschel mixer. went. The fiber dispersibility is shown in Table 1.

Example 8 100 parts by weight of used newspaper paper as in Example 1 and 45 parts by weight of polypropylene as in Example 1 were mixed with a Henschel mixer FM.
The mixture was heated and stirred and kneaded at 280 ° C. using a Model -20B, and then granulated with a disk pelletizer Model F-5 [3 mmφ die diameter used by Fuji Paudal Co., Ltd.]. The fiber dispersibility is shown in Table 1.

Example 9 100 parts by weight of used newspaper paper as in Example 1 and 15 parts by weight of polypropylene as in Example 1 were mixed with a Henschel mixer FM.
After heating, stirring and kneading to 215 ° C. in a −20B type, granulation was performed with a disk pelletizer F-5 type. The fiber dispersibility is shown in Table 1.

Example 10 A waste latex-impregnated paper was used for waste paper.
Was crushed into a 3 mm square shape by the crusher CS cutter used in the above. Example 1 100 parts by weight of crushed latex-impregnated paper
50 parts by weight of the same polypropylene was heated and stirred at 240 ° C. using a Henschel mixer, and then granulated as in Example 9. The fiber dispersibility is shown in Table 1.

Example 11 100 parts by weight of used newspaper used in Example 1 and an ethylene-based low molecular weight polyolefin [High Wax 2 manufactured by Mitsui Chemicals, Inc.]
203A] The same treatment as in Example 10 was carried out at a mixing ratio of 20 parts by weight and 6 parts by weight of calcium carbonate as in Example 6. The fiber dispersibility is shown in Table 1.

Example 12 The recovered recycled polypropylene laminated paper [laminated polypropylene ratio: 20.9% by weight] was roughly crushed into a 3 mm square shape using the same crusher CS cutter as in Example 1. 100 parts by weight of the crushed polypropylene laminated waste paper and 20 parts by weight of the same polypropylene as in Example 1 were blended, and the same treatment as in Example 10 was performed. Table 1 shows the fiber dispersibility results.
Shown in

Example 13 The collected waste polyethylene laminated kraft paper for packaging [laminated polyethylene ratio: 16.5% by weight, hereinafter polyramid kraft paper] was coarsely crushed by a crusher CS cutter [3 mm screen] to obtain a roughly 3 mm square polystyrene. Lami Kraft paper was obtained. This crushed poly kraft paper 10
0 parts by weight and 45 parts by weight of the same polypropylene as in Example 1 were heated and kneaded with a Henschel mixer type FM-20B up to 240 ° C., and then granulated with a disk pelletizer type F-5. The fiber dispersibility is shown in Table 1.

Example 14 Example 13 was carried out in the same manner as in Example 13, except that low-density polyethylene [403P melt flow rate, 7 g / 10 minutes, manufactured by Mitsui Chemicals, Inc.] was used instead of polypropylene. The fiber dispersibility is shown in Table 1.

[0034]

[Table 1]

Comparative Example 1 The procedure of Example 1 was repeated, except that the heating, stirring and kneading of the Henschel mixer was performed up to 200 ° C. The fiber dispersibility is shown in Table 2.

Comparative Example 2 The procedure of Example 1 was repeated, except that the heating, stirring, and kneading of the Henschel mixer was performed up to 210 ° C. The fiber dispersibility is shown in Table 2.

Comparative Example 3 100 parts by weight of used newspaper paper and 100 parts by weight of the polypropylene used in Example 1 were heated and stirred and kneaded at 170 ° C. using a Henschel mixer FM-20B type. Table 2 shows the results.

COMPARATIVE EXAMPLE 4 100 parts by weight of used newspaper paper as in Example 1 and 10 parts by weight of the polypropylene used in Example 1 were mixed with Henschel mixer F
The mixture was heated and stirred and kneaded to 199 ° C. using an M-20B type. Table 2 shows the results.

Comparative Example 5 100 parts by weight of used newspaper paper (without mixing a thermoplastic resin) as in Example 1 were mixed with a Henschel mixer FM-20B type for 18 parts.
Heating and stirring treatment was performed up to 2 ° C. Table 2 shows the results.

Comparative Example 6 The procedure of Example 3 was repeated, except that the heating, stirring, and kneading of the Henschel mixer was performed up to 210 ° C. The fiber dispersibility is shown in Table 2.

COMPARATIVE EXAMPLE 7 The procedure of Example 4 was repeated, except that the heating, stirring and kneading of the Henschel mixer was performed up to 210 ° C. The fiber dispersibility is shown in Table 2.

Comparative Example 8 In Example 5, the blending ratio of polypropylene to waste paper was 100 parts by weight, and a Henschel mixer FM-20B was used.
The mixture was heated and kneaded to 170 ° C. in a mold. The fiber dispersibility is shown in Table 2.

Comparative Example 9 In Example 6, the mixing ratio of polypropylene to waste paper was 125 parts by weight, and a Henschel mixer FM-20B was used.
The mixture was heated and kneaded to 170 ° C. in a mold. The fiber dispersibility is shown in Table 2.

Comparative Example 10 Commercially available 400 mesh pass fine powdered cellulose KC floc instead of waste paper fiber [Nippon Paper Industries Co., Ltd.]
W-400], 100 parts by weight of this and 100 parts by weight of the same polypropylene as in Example 5 were heated and stirred at 170 ° C. using a Henschel mixer to obtain a comparative example with the ground paper fibers of the present invention. . Table 2 shows the fiber dispersibility.
Shown in

Comparative Example 11 The same operation as in Example 8 was carried out except that the heating, stirring and kneading treatment in the Henschel mixer was changed to 210 ° C. The fiber dispersibility is shown in Table 2.

Comparative Example 12 The procedure of Example 13 was repeated, except that the heating, stirring and kneading of the Henschel mixer was performed up to 210 ° C. The fiber dispersibility is shown in Table 2.

Comparative Example 13 100 parts by weight of waste newspaper paper crushed into a 3 mm square of Example 1 and 45 parts by weight of polypropylene as in Example 1 were combined with Labo Plastomill 50MR type (manufactured by Toyo Seiki Seisakusho Co., Ltd.), Bamba. 57.1 Remixer [Toyo Seiki Seisakusho Co., Ltd.]
g, and heated and kneaded at 240 ° C. Table 2 shows the fiber dispersibility results.

Comparative Example 14 100 parts by weight of waste newspaper paper crushed into a 3 mm square of Example 1 and 100 parts by weight of polypropylene similar to Example 1 were combined with Labo Plastomill 50MR type (manufactured by Toyo Seiki Seisaku-sho, Ltd.)
80 g for Banbury mixer [manufactured by Toyo Seiki Seisakusho Co., Ltd.]
Then, the mixture was heated and stirred and kneaded at 180 ° C. Table 2 shows the fiber dispersibility results.

Comparative Example 15 The procedure of Comparative Example 14 was repeated except that the heating, stirring and kneading treatment was performed at 240 ° C. Table 2 shows the fiber dispersibility results.

Comparative Example 16 The procedure of Comparative Example 14 was repeated except that the heating, stirring and kneading treatment was performed at 270 ° C. Table 2 shows the fiber dispersibility results.

[0051]

[Table 2]

Example 5, Example 6, Example 8, Example 13 and Comparative Example 3, Comparative Example 8, Comparative Example 9, Comparative Example 1
0, Comparative Example 11, Comparative Example 12, Comparative Example 13, Comparative Example 1
4. After kneading in Comparative Examples 15 and 16, the mixture was mixed with a Henschel mixer (roller mixer for Comparative Examples 13 to 16) so that the used paper mixing ratio was 50% by weight, and the melt flow was performed. The late was measured. Table 3 shows the results. From Table 3, it can be seen that the waste paper material for resin blending according to the present invention has MFR which is a measure of fiber dispersibility and molding fluidity.
Is excellent. Comparative Examples 8 and 9 have good fiber dispersibility, but MF
R is unmeasurable, and Comparative Example 10 shows fiber dispersibility and MF
R is good but has the disadvantage of being expensive.

[0053]

[Table 3]

FIG. 3 is a photograph showing the state in which the waste paper fiber length of the example is dispersed in the sheet, and FIG.
(B) is for comparison-commercially available KC floc-100 [100 mesh pass ratio 90% manufactured by Nippon Paper Co., Ltd.-catalog value] and W-400 [400 mesh pass ratio 90% manufactured by Nippon Paper Co., Ltd.-catalog value] It is each organization chart photograph.

[0055]

The used paper material for resin blending according to the present invention is obtained by finely pulverizing used paper, so that the used paper composite resin composition can exhibit good fluidity and dispersibility during hot melting. In particular, when incinerated polyethylene laminate kraft waste paper is used, it can be effectively used as a thermoplastic resin filler at low cost.

The present invention also provides a bulk specific gravity of 0.15 to 0.6.
By setting it to 0, productivity and workability can be improved when the used paper material for resin blending is used as a filler in the next step. In other words, when the resin-mixed waste paper material after the heat treatment is bulky as in the past, the problems such as dropping of the hopper with the existing screw extruder, poor penetration into the screw, poor productivity, and poor kneading of the waste paper are eliminated. Is done. Further, by granulating the waste paper material for resin blending according to the present invention by using a non-screw type compression granulator, it is possible to advantageously perform a volume reduction treatment in terms of production.

The method for producing a used paper material for resin blending according to the present invention is capable of shortening used paper fibers at low processing cost, and obtaining a used paper material for resin blending excellent in dispersibility and moldability. it can.

In the method for producing a used paper material for blending a resin according to the present invention, the thermoplastic resin ratio is set to 15 to 70 parts by weight of the thermoplastic resin per 100 parts by weight of the used paper.
The effect of reducing the volume of waste paper fibers due to the melting of the resin, the load on the equipment and the accompanying heat generation, and the effect of increasing the temperature can be efficiently obtained when using equipment that raises the temperature by frictional heat. For example, when using a high-speed mixer, if the blending ratio of the thermoplastic resin is too small than the blending ratio of the present invention, it is not possible to efficiently raise the temperature due to frictional heat, which is not preferable in terms of production, and the blending ratio of the present invention is low. If the rate exceeds the ratio, the gelled and molten resin completely covers the surface of the waste paper raw material, and the fusion of the mixture becomes intense. It is solved by the invention.

In the heat treatment of waste paper using the high-speed mixer according to the present invention, the peripheral speed at the tip of the mixer blade is 5 to 35.
By setting m / s, production efficiency is improved.

In the heat treatment using the high-speed mixer according to the present invention, the heat treatment is performed at a mixing temperature in the range of 215 to 280 ° C., so that the dispersing effect of the waste paper by the high-speed mixer is improved. In addition, the effect of reducing the volume of the mixture can be obtained, and the productivity in the next and subsequent steps can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a ratio of a thermoplastic resin to waste paper and a mixer kneading time indicating productivity.

FIG. 2 is a graph showing the relationship between the bulk density of each kneaded material and the temperature conditions of waste paper heating using a high-speed mixer.

FIG. 3 is an organization photograph showing a state in which the used paper fiber length of one embodiment according to the present invention is dispersed in a sheet.

FIGS. 4A and 4B are for comparison—commercially available KC Floc W—
It is each organization chart photograph of 400 and W-100.

Claims (5)

[Claims] 1. 100 parts by weight of waste paper and a thermoplastic resin 15 to
A mixture containing 70 parts by weight, wherein waste paper in the mixture is pyrolyzed to be formed into a fine powder, and has a bulk specific gravity of 0.15 to 0.60 as a whole for compounding resin. Waste paper material. 2. The waste paper material for resin mixing according to claim 1, wherein the waste paper material for resin mixing is formed in a granular shape. 3. 100 parts by weight of waste paper and thermoplastic resin 15 to
The mixture containing 70 parts by weight is subjected to a heat treatment for thermally decomposing waste paper with a high-speed mixer, and has a bulk specific gravity of 0.15 to 0.60.
A method for producing a used paper material for resin blending, characterized in that: 4. Using a high-speed mixer, the peripheral speed at the tip of the mixer blade is 5 to 35 m / s, and the kneading temperature is 215 to 28.
The method for producing a used paper material for resin blending according to claim 3, wherein a heat treatment for thermally decomposing the used paper at 0 ° C is performed. 5. The method for producing a recycled paper material for resin blending according to claim 3, wherein the recycled paper material for blending resin according to claim 3 or 4 is granulated by a non-screw type compression granulator. .