JPH106335A - Recovery of waste synthetic paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To individually separate and recover a synthetic resin being a main raw material of synthetic paper and printing ink by peeling a printing ink coating film from the used synthetic paper. SOLUTION: Synthetic paper 81 is crushed to form a large number of small pieces 82 to be treated and impact grinding force is applied to these crushed individual small pieces 82 to be treated and the films 84 of printing ink on the surfaces of the small pieces 82 to be treated are destructed by this impact grinding force, mainly, impact force and the coating films 84 finely ground by the bending action repeatedly applied to the small pieces 82 to be treated are peeled from the surfaces of the small pieces 82 to be treated and classified to obtain a recovered resin material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recovering waste synthetic paper, and more particularly, to a method for printing posters, calendars, ballot papers, pamphlets, maps, etc., packaging films for various articles, and various other uses. The present invention relates to a method for collecting waste synthetic paper, in which a coating film of printing ink is peeled from used synthetic paper, and a resin material base material of a synthetic resin as a raw material of the synthetic paper is collected as a collected resin material.

[0002]

2. Description of the Related Art Synthetic paper has been processed to give paper-like properties, especially appearance (whiteness, opacity, etc.) and a wide range of printability, to a film or sheet-like base material made of a synthetic resin material as a main raw material. It is used for paper-like purposes, and has higher whiteness, better smoothness, better water resistance, and better dimensional stability against humidity than high-grade printing paper (art paper, coated paper). For good reasons, this synthetic paper is subjected to printing, such as color printing, and is used in a large amount in various applications.

In the field of synthetic paper market applications, posters, calendars, and the like can be used as substitutes for conventional paper in the fields of high-quality printing paper (art paper, coated paper), tracing film, packaging, and paperboard. , Ballot paper, packaging materials, and various other uses.

[0004] A more specific example of the field of use of synthetic paper is its use as an election poster. Since election posters are posted outdoors, they are used by paying attention to the water resistance, moisture resistance, and the like of synthetic paper.

[0005] By the way, the election poster is removed from the bulletin board by the election administration committee after the elapse of the election period and collected. The amount of election posters collected is enormous.
Therefore, even if only waste synthetic paper used as an election poster is taken, an effective recycling method is expected.

[0006] As a method of reusing a synthetic paper printed on a synthetic paper, such as a poster, a calendar, a ballot, and a waste synthetic paper used for other purposes, the recovered synthetic paper is melted and molded. To produce processed products, and the heat generated by incineration in incinerators
A method of reusing as heat energy for district cooling / heating, a heated water pool, and the like has been proposed.

[0007]

Most of the above-mentioned waste synthetic paper is printed on the entire surface, and the printing is performed with a printing ink containing an organic solvent such as xylene or toluene. The ink coating is strongly welded to the surface of the waste synthetic paper, and it is difficult to remove the printing ink coating from the synthetic paper.

[0008] For this reason, printing ink is inevitably mixed into the reworked product formed by using the collected waste synthetic paper as a raw material resin, and the reworked product is unspecified by the mixing of the printing ink. It is colored. Since the reprocessed product produced by recycling synthetic paper in this way becomes colored, reprocessed products produced by regenerating synthetic paper include hangers, flowerpots, nursery boxes, and piles in parks. For example, it is limited to a material in which coloring due to mixing of printing ink is not a problem, and cannot be used for other wide-ranging uses.

The present invention has been developed to solve the above-mentioned problems, and a coating film of a printing ink is peeled, crushed, and classified from used synthetic paper by a relatively simple and easy method. It is an object of the present invention to provide a method for recovering waste synthetic paper that enables a synthetic resin material, which is a main raw material of synthetic paper, to be used as a recovered resin material and to provide the recovered resin material with a wide range of reuse. .

[0010]

In order to achieve the above object, a method for recovering waste synthetic paper according to the present invention comprises separating a coating film of printing ink from a resin material base material of waste synthetic paper and recovering the resin material. A crushing step of crushing the waste synthetic paper into a plurality of small pieces to form small pieces to be treated, and applying an impact grinding force to each of the crushed small pieces to be treated to form a printing ink. And removing the coating film and pulverizing and classifying the coating film, and collecting waste synthetic paper using the resin material base material constituting the synthetic paper as a recovery resin material.

The crushed individual pieces to be treated are subjected to an impact milling force to peel off the coating film of the printing ink, and the coating film is crushed and classified, and the synthetic paper is crushed. The step of using the constituent resin material base as the recovered resin material can be repeated a plurality of times.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for collecting waste synthetic paper according to the present invention will be described with reference to the drawings.

[Synthetic Paper to be Treated] The synthetic paper to be treated according to the present invention is applicable to synthetic paper made from various synthetic resins such as polystyrene, polyvinyl chloride, polypropylene and polyester. Synthetic papers manufactured by various methods such as an internal paper forming method, a surface coating method, a surface treatment method, and a fiber method can be treated individually or in a mixed state.

However, the synthetic paper manufactured by each of the manufacturing methods described above may be peeled, crushed,
Since the processing time by the classification means is slightly different, it is preferable that each of them be processed separately.

The synthetic paper produced by the above-mentioned internal papermaking method is mixed with a synthetic resin by adding a filler (stabilizer, dispersant, etc.), melt-kneading with an extruder, and extruding through a die slit. Synthetic paper formed to obtain writability, printability, opacity, etc. when forming a film by means of a film. Similar to paper, a synthetic paper with mineral white paint mixed with glue such as casein or gelatin to form a white coating layer, giving whiteness, writing properties, and absorption of printing ink. Synthetic paper manufactured by the processing method is a synthetic paper in which the surface of the synthetic resin film is chemically or physically treated to improve writability, printability, opacity, etc., and further manufactured by the fiber method. Synthetic paper is a synthetic paper Rami with combined impart whiteness by diffused reflection of the fiber itself, by a gap caused by entanglement between fibers, a synthetic paper gave writability, printability.

[Synthesis Paper Crushing Step] After the above-mentioned synthetic paper is collected, it is crushed in a crushing step to form small pieces to be treated having an appropriate size.

In FIG. 1, a synthetic paper 81 is cut into a band having a width of about 5 mm by a known cutting machine such as a slitter or the like, and then the band-shaped synthetic paper 81 is cut by a known crushing means (for example, this embodiment). Then, for convenience, it is thrown into a "cutter mill") and crushed into rectangular or square or other irregular shaped pieces having a long side or major axis of about 3 to 5 mm, or triangular, trapezoidal or rhombic.

FIG. 2 shows a cutter mill 1 as an example of the crushing means.
20 is shown. Reference numeral 121 denotes a cutter mill main body, which is a cylindrical casing having an input port 123 on the upper surface, and a cutter support 124 which is rotatably supported by the cutter mill main body 121 and vertically rotated by rotation driving means (not shown). Are provided on the outer periphery of the cutter support 124 so as to provide four horizontally long rotary blades 125 so as to form an equal angle of 90 degrees in the rotation direction of the cutter support 124, and the cutting edges of these four rotary blades 125 are provided. They are located on the same rotation locus. Further, the two fixed blades 126 are fixed to the cutter mill main body 121 at a position substantially symmetrical with the rotation locus of the cutting edge of the rotary blade 125 via a slight gap with respect to the rotation locus of the cutting edge of the four rotary blades 125. The inside of the cutter mill main body 121 is divided by the fixed blade 126, the cutter support member 124, and the rotary blade 125 to form a charging chamber 127 and a crushing chamber 128. The charging port 123 communicates with the charging chamber 127. The clearance between the second solid blade 126 and the rotary blade 125 can be freely adjusted so that the object to be crushed can be cut into a desired size, or crushed in a broad sense. The clearance of this embodiment is 0.2
0.3 mm. The crushing chamber 128 is partitioned by the mesh screen 129 so as to surround the rotation locus of the rotary blade 125 between the two fixed blades 126. In addition,
In this embodiment, the screen 129 is made of a punching metal in which holes having a diameter of 8 mm are formed innumerably. Further, an outlet 131 for discharging the small piece to be processed 82 is provided below the crushing chamber 128.

In the above-mentioned cutter mill 120, the above-mentioned band-shaped synthetic paper 81 having a width of 5 mm is inserted from the input port 123, and the cutter support 124 is rotated at 800 rpm by a rotation driving means (power 5.5 KW) not shown. Synthetic paper 81
Is formed through a screen 129 between the rotary blade 125 and the fixed blade 126 of the cutter support 124, the shape and the area are undefined, but the long side or the long diameter is a rectangle such as a rectangle or a square having a size of about 5 × 5 mm or less; Or triangles, trapezoids,
It is crushed into irregular shaped small pieces 82 such as diamonds and discharged from the outlet 131.

The crushing means is not limited to the cutter mill described above. For example, various mono-cutters, shredders, crushers, etc., such as Gainax crusher manufactured by Horai Co., Ltd. or roll crusher manufactured by Nara Machinery Co., Ltd. "Crusher" can be used. `` Crusher '' is, for example, provided in parallel two axes rotating inward each other in a crusher body having an input port of the crushed object in the upper part, while providing a plurality of rotating blades at a predetermined interval on each axis, Provided to cut the object to be crushed into crushed pieces composed of appropriately large pieces by three claw blades which are meshed with each other on the outer periphery of each rotary blade of the shaft and project from the outer peripheral surface of each rotary blade so as to form an equal angle. Have been. The crushed material introduced from the upper inlet is drawn into the inside by the claw blades of the biaxial rotating blades rotating inward to each other, and continuously between the outer peripheral edges of the rotating blades rotating in a meshed state. While being slit by the acting shearing force, the material is crushed and cut by the compressing force acting at the time of retraction while forming a crushed piece. This crushed piece is
It passes through a screen provided below the rotating blade of the shaft and is discharged from a discharge port.

[Peeling / Pulverization / Classification Step] In this [Peeling / Pulverization / Classification Step], an impact grinding force is applied to the small piece 82 to be treated crushed in the above-mentioned [Crushing Step]. The coating film of the printing ink of the small piece to be processed 82 is peeled off mainly by the impact force, and peeled off to the synthetic resin piece 83 and the coating film 84 of the printing ink. This is a step of classifying the coating film 84 and individually collecting the coating film 84. Specifically, by repeatedly applying the bending action by the impact grinding force to the small piece 82 to be treated,
The coating film of the printing ink is finely crushed and peeled off from the surface of the small piece to be processed 82, or the surface of the small piece 82 to be processed is partially cut together with the coating film 84 of the printing ink,
The coating film 84 of the printing ink is peeled and crushed. Further, the centrifugal force acts on each of the small pieces 82 to be processed and the separated coating film of the printing ink, whereby the coating film of the printing ink is applied to the small pieces 8 to be processed.
2 easily separates from the surface. Further, since the temperature of the coating film 84 of the printing ink rises due to the frictional heat with the small pieces 82 to be processed due to the impact force, the coating film is dried and hardened, so that the coating film of the printing ink is more easily crushed. .

FIG. 6 shows an example of the configuration of an entire apparatus including a peeling / classifying means (in this embodiment, referred to as "separator" for convenience) used in the method of the present invention.

Referring to FIG. 6, first, the overall outline of the separator 130 will be described. The separator 130 has a supply inlet 132 into which the small pieces 82 to be treated are introduced. Outlet 1 for taking out a synthetic resin piece 83 formed by peeling off the coating film 84 of the printing ink from the small piece 82 to be processed
53, the coating film 84 of the printing ink separated and crushed from the synthetic resin piece 83 (FIG. 1), and the surface of the small piece 82 to be treated was shaved by the impact-milling force to form dust and fiber. An outlet 152 for discharging a resin material or the like is provided.

The small pieces 82 that have been processed in the previous step are supplied to the supply inlet 132 through a supply pipe 231. The outlet 153 is connected to the supply port 132 by the communication pipe 23.
5, and a pipe 236 from a compressed air supply source (not shown) is connected to the outlet side of the communication pipe 235. A flow straightening plate is provided at a communication portion of the pipe 236 so that compressed air mainly flows to the supply inlet 132 side.
A branch pipe 237 is provided for branching the communication pipe 235 and communicating with the collection tank 240 for the synthetic resin piece 83. At a branch point of the branch pipe 237, for example, a three-way solenoid valve 238 which can be switched at appropriate intervals by a timer circuit, for example, is provided. Is provided. On the other hand, the discharge port 152 communicates with the collection tank 250 via a discharge pipe 239, and the coating film 8 discharged from the discharge port 152.
4 and a discharge pipe 239 through which dust and the like are interposed
And is collected in the collection tank 250.

3 to 5, the internal structure of the separator 130 will be described.
Reference numeral 2 denotes an opening communicating with the center of the fixed disk 131, a fixed end plate 133 is opposed to the fixed disk 131 with a processing space 155 therebetween, and an outer peripheral edge of each fixed end plate 133 is provided on the fixed disk 131 as a peripheral side plate. Fix at 135. In the processing space 155, there is provided a movable disk 141 that is rotationally driven by a rotating horizontal shaft 142.
143. The rotating horizontal shaft 142
Is rotationally driven by a rotational driving means such as a motor 161.

On the fixed disk 131, each fixed pin 134 is sequentially planted on a plurality of concentric rotation trajectories a _{1 to} a ₆ (relative to the movable disk 141) (FIG. 5). and, on the other hand, on the movable disc 141 is sequentially the movable pin 144 enters alternately between the rotation locus of the respective fixing pins 134 on a plurality of different rotational locus b ₁ ~b ₆ and each fixed pin 134 The fixed and movable pins 134 and 144 are arranged so that the coating of the printing ink on the surface of the processing target piece 82 can be separated or separated by the impact attrition force between the fixed and movable pins 134 and 144. .

More specifically, the number of the fixed pins 134 is 16 on the rotation locus a ₁ near the center of the fixed disk 131.
This rotation locus a positioned on the outer peripheral side of the rotation locus a ₁
24 is a top _2, 32 is on the rotary locus a ₃ sequentially positioned toward the more outer peripheral side, 36 present in the upper rotation locus a _4, 40 present in the upper rotation locus a _5, 42 present in the upper rotation locus a ₆ Are planted respectively. On the other hand, the number of the movable pins 144 is four on the rotation trajectory b ₁ near the center of the movable disk 141, four on the rotation trajectory b ₂ located on the outer periphery side of the rotation trajectory b ₁ , and more on the outer periphery. Four on the rotation trajectory b ₃ , _four on the rotation trajectory b _{4, four} on the rotation trajectory b ₅ , and _six on the rotation trajectory b ₆ , which are sequentially located toward the trajectory b ₃ .

Actually, each of the fixed and movable pins 134, 1
The grinding force applied to the small piece to be processed 82 is reduced by increasing the clearance between the pieces 44, and the grinding force is increased by decreasing the clearance.

Further, in FIG. 3, a discharge space 15 is provided on the outer peripheral side of the movable disk 141 and on the inner peripheral side of the peripheral side plate 135.
A screen 151 of a predetermined mesh in which pores having a desired diameter are formed by punching is provided around the screen 6, and a discharge port 152 is provided below the discharge space 156. In this embodiment, the screen 151 is a mesh having a diameter of 1 mm, but is usually a mesh having a diameter of 1 mm or less, preferably a mesh having a diameter of 0.7 mm.

The screen 151 of the processing space 155
An outlet 153 is provided in the lower part of the
Reference numeral 3 denotes a collection tank 240 for communicating with the supply inlet 132 via the communication pipe 235 as described above, and for collecting the resin material collected via the branch pipe 237 which branches off the supply inlet side of the communication pipe 235. In communication with As another example, a plug valve for opening and closing control is provided in the outlet 153, and the outlet 153 is supplied and supplied through a blower 158 that sucks air in the separator 130 as shown in FIG. It can also communicate with the mouth 132.

Therefore, in the separator 130, when the rotating horizontal shaft 142 is rotated by the rotation driving means of the motor 161 to rotate the movable disk 141 and the small pieces 82 to be processed are supplied to the supply inlet 132, The small piece 82 is located at the center of the processing space 155 and has fixed and movable pins 13.
4,144 by the impact attrition force
2 is beaten by the impact of the fixed and movable pins 134 and 144, and the coating film 84 on the surface is finely crushed. Since the bending action is repeatedly applied to the small pieces 82 to be processed, the coating film 84 finely crushed is coated. It peels off from the surface of the processing piece 82.
The surface of the small piece 82 to be processed is shaved and peeled off together with the coating film by the application of the impact grinding force.

Each of the small pieces 82 to be processed by the impact grinding force
The frictional heat increases the temperature of the coating 84 on the surface of the small piece 82 to be treated, and further increases the coating 84 from the surface of the small piece 82 to be treated.
Is easily peeled off. In other words, the temperature of the coating film 84 rises due to frictional heat, so that the coating film 84 is dried and hardened. In this state, the coating film 84 is repeatedly beaten and bent by the impact of the impact crushing force. It is broken and peeled.

Although the shape of the recovered synthetic resin piece 83 is hardly changed as compared with the small piece 82 to be processed, the fibrous material scraped off from the surface of the peeled coating film 84 and the small piece 82 to be processed. The powdery resin material and the white coating layer have a diameter of about 0.5 to 2 mm .

The coating film 84 separated from the small piece 82 to be processed
And the resin material and the white coating layer scraped off from the surface of the synthetic paper, the centrifugal action of each movable pin 144 causes the screen 15
After passing through 1 and being classified into the discharge space 156, it is sucked and discharged from the discharge port 152 to the outside through the blower 157 (FIG. 6).

In this embodiment, the blower 157 is 37 horsepower, 5 kg / cm ² / pressure, 2
m ³ / min, 18.5 hp for small aircraft, 5 kg / cm ² /
At a pressure of 1 to 1.5 m < ³ > / min, the coating material 84 separated from the small pieces to be treated and the resin material or white coating layer scraped off from the surface of the synthetic paper are sucked together with the air in the separator 130.

On the other hand, the synthetic resin piece 83 having a size that does not pass through the screen 151 remains in the screen 151. Into the synthetic resin piece 83, a small piece to be treated 82 whose surface is coated with a coating film 84 is mixed. However, since the outlet 153 and the supply inlet 132 communicate with each other through the communication pipe 235, the small piece 82 to be processed and the synthetic resin piece 83 taken out from the outlet 153 are returned to the supply inlet 132 to be separated by the separator 132. In the area 130, the material is again hit by impact grinding force and repeatedly subjected to a bending action, and the coating film 84 remaining on the surface of the small piece to be treated 82 is removed.
The flakes of the synthetic resin piece 83 are separated from the synthetic resin piece 83, and the coated film 84 separated from the synthetic resin piece 83 is pulverized, passes through the screen 151, and is discharged by the blower 157 to the discharge port 152. Is discharged to the outside. Although the synthetic resin pieces 83 are refluxed, most of them remain in the screen 151 without being pulverized as finely as they pass through the screen 151. The above-described peeling / classifying process can be repeated a plurality of times as necessary until the coating film 84 of the small pieces 82 to be treated in one batch is almost separated and removed through the discharge port.

The above-mentioned separator 130 is rotated by the rotation driving means 1
61, the downstream side of the communication pipe 235 is opened by a three-way solenoid valve 238 and the branch pipe 237 side is closed,
By supplying the compressed air from the pipe 236 to the communication pipe 235, the compressed air generates an airflow that circulates from the communication pipe 235 to the supply inlet 132, the processing space 155, the outlet 153, and again to the communication pipe 235. When each piece 82 to be processed of one batch is supplied to the supply inlet 132 through the supply pipe 231, the piece 8 to be processed is processed in the separator 130 and is processed.
2 is discharged to the collection tank 250 through the screen 151 by the blower 157 through the screen 151, while the synthetic resin pieces 8 remaining in the screen 151 are removed.
3 is sucked into the communication pipe 235 by the circulating airflow, fed again to the processing space 155 and processed in the separator 130,
This series of steps may be repeated as many times as necessary until most of the coating 84 in one batch is separated and removed. Next, after the above processing is completed, the downstream side of the communication pipe 235 is closed with a three-way solenoid valve 238 and the branch pipe side is opened, so that the synthetic resin piece 83 left in the screen 151 is removed from the communication pipe 235. It is collected in the collection tank 240 through the branch pipe 237.

Note that, instead of the three-way solenoid valve 238, a solenoid valve for opening and closing the branch pipe 237 and the communication pipe 2
It is also possible to provide an electromagnetic valve that opens and closes the downstream side of 35, and to open and close these two electromagnetic valves alternately.

[0039]

EXAMPLES The results of recovering a resin material from synthetic paper printed with offset printing ink by using the above-described method of the present invention are described below.

As the offset printing ink, a non-paper printing ink was used. Table 1 shows the composition of the non-paper offset printing ink.

[0041]

[Table 1]

The results of recovering the resin material by the method of the present invention using the synthetic paper manufactured by the method of forming an internal paper formed by printing with the printing ink, the surface coating method, and the surface treatment method according to the present invention are described below. Examples are shown in Example 1, Example 2 and Example 3, respectively.

Example 1 The synthetic paper manufactured by the internal papermaking method used in the present example was prepared by using a polypropylene resin as a main raw material, polymerizing the surface layer on the front and back of a longitudinally stretched base layer, and then performing the polymerization. After stretching the film in the transverse direction,
As shown in FIG. 7A, the surface layer 2 stretched and oriented only in the horizontal direction is provided on the front and back sides of the base layer 260 stretched and aligned in the vertical and horizontal directions.
62 is formed in a three-layer structure.
The holes 264 formed in the inside of the film at the time of this stretching impart printability, writability, and whiteness to the polypropylene resin film so that the film can be used for paper.

The thickness of the synthetic paper to be processed is
210μ (70μ per layer) and the thickness of the coating film of the printing ink is 10μ.

The coating weight of the synthetic paper and the printing ink is 95% by weight and 5% by weight, respectively.

After 200 g of the above synthetic paper was crushed into small pieces of about 5 mm on a side by a cutter mill, the small pieces were put into a separator rotating at 55 Hz and 1,650 rpm, and subjected to impact grinding for about 20 minutes. Added force.

As a result, 100 g of the white synthetic resin piece from which the coating of the printing ink was removed, and 10 g of the coating of the printing ink
0 g was recovered.

The state of the recovered resin material and the coating film of the printing ink is such that, although many wrinkles are observed in the resin material as a whole, the coating film of the printing ink is completely removed, while In the coating of the printing ink recovered by passing through, mixed with the coating of the crushed printing ink,
It was confirmed that some fibrous resin material to which the coating film of the printing ink adhered was contained.

From the above results, not only the coating of the printing ink adhering to the small pieces to be treated is peeled off by the application of the impact milling force, but also the surface part of the surface layer of the synthetic paper is partially stretched in the stretching direction. It is considered that the film was torn in a fibrous form and peeled off together with the coating film of the printing ink.

Since the recovered resin material is one from which the coating film of the printing ink has been completely removed, it can be melted again to be regenerated as synthetic paper, and also to various molded articles. Its recycling uses are extensive, such as being processed.

[Example 2] The synthetic paper manufactured by the surface coating method used in this example has a white color on the surface of a base layer 260 made of polypropylene resin as a main material as shown in FIG. 7 (B). Pigment is a synthetic paper in which a white paint formed by mixing gelatin is applied to form a white coating layer 272, and the polypropylene sheet has printability, writability, and whiteness.

The thickness of the synthetic paper to be processed is
150μ, and the thickness of the coating film of the printing ink is 5μ.

The weight ratio of the synthetic paper and the coating film of the printing ink is 97% by weight and 3% by weight, respectively.

After 200 g of the above synthetic paper was crushed by a cutter mill into small pieces of about 5 mm on a side, the small pieces were put into a separator rotating at 55 Hz and 1,650 rpm, and subjected to impact grinding for about 15 minutes. Added force.

As a result, 120 g of the white synthetic resin piece from which the coating film of the printing ink was removed, and the coating film 80 of the printing ink were removed.
g was recovered.

Regarding the state of the recovered resin material and the coating film of the printing ink, many wrinkles are observed in the resin material as a whole, and the white coating layer 272 is peeled off and the surface gloss is lost. However, it was recovered as a white flake from which the coating film of the printing ink had been completely removed. On the other hand, the coating film of the printing ink recovered through the screen was recovered as a crushed powder.

In the case of ordinary paper, the ink penetrates into the paper and, at the same time, oxidatively polymerizes and solidifies with time, but in the synthetic paper used in this example, the penetration of the ink was formed on the surface of the synthetic paper. Applying an impact grinding force to the white coating layer 272 because it does not permeate into the base layer 260 made of a non-water-absorbing polypropylene film and slightly adheres to the surface of the base layer 260 It is considered that the coating film of the printing ink was completely removed together with the surface coating layer.

The resin material recovered in this embodiment has a high purity as a synthetic resin and is suitable for recycling because the white coating layer is also removed therefrom.

Since the recovered resin material is one from which the coating film of the printing ink has been completely removed, it can be melted again to be regenerated as synthetic paper, and also to various molded articles. It has a wide range of recycling applications, such as being capable of processing.

Example 3 As synthetic paper manufactured by the surface treatment method used in the present example, a paper obtained by oxidizing the surface of a polyethylene film by a flame treatment to improve printability was used.

As shown in FIG. 7 (C), the synthetic paper has a deteriorated layer 282 formed by a chemical change in the vicinity of the surface of the polyethylene film by a flame treatment. The presence of the deteriorated layer 282 allows printing and writing on the polyethylene film. It gives the gender.

The thickness of the synthetic paper to be processed is
150μ, and the thickness of the coating film of the printing ink is 10μ.

The weight ratio of the synthetic paper and the coating film of the printing ink is 93% by weight and 7% by weight, respectively.

After 200 g of the above-mentioned waste synthetic paper was crushed into small pieces of about 5 mm on a side by a cutter mill, the small pieces were put into a separator rotating at 55 Hz and 1,650 rpm, and subjected to impact grinding for about 15 minutes. Crushing force was applied.

As a result, 120 g of the translucent synthetic resin piece from which the printing ink coating was removed and 80 g of the printing ink coating peeled off from the surface of the synthetic paper were recovered.

Regarding the state of the recovered resin material and the coating film of the printing ink, many wrinkles were observed in the resin material as a whole, and a part of the deteriorated surface layer 282 was scraped off together with the coating film of the printing ink. Although many fine irregularities were formed on the surface, the coating film of the printing ink was completely removed and collected as a translucent flake.

In the synthetic paper used in this example, the deteriorated layer formed by the flame treatment of the surface has a reduced strength as compared with the other parts, so that it is printed by applying a grinding impact force. It is considered that not only the coating film of the ink was removed but also the deteriorated layer was scraped off from the surface of the synthetic paper.

Since the recovered resin material is one from which the coating film of the printing ink has been completely removed, it can be melted again to be regenerated as synthetic paper, and also to various molded articles. Its regenerative uses are extensive, such as being processable.

[0069]

Since the present invention is configured as described above, it has the following effects.

By a relatively simple and easy method, the coating film of the printing ink can be peeled off and removed from the synthetic paper to be treated, and only the synthetic resin of the main material can be efficiently recovered from the synthetic paper. It was made available.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a system explanatory diagram of processing steps schematically and in principle showing an outline when a method of a basic embodiment of a method of collecting waste synthetic paper, which is an example of a processing object of the present invention, is applied.

FIG. 2 is an overall perspective view showing a main part of a cutter mill (crushing means) used in the embodiment of the present invention.

FIG. 3 shows a separator (peeling / separation) used in an embodiment of the present invention.
It is a front view which shows the principal part of a crushing and classifying means.

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a cross-sectional view of a main part taken along line VV in FIG. 3;

FIG. 6 shows a separator (peeling / separation) used in an embodiment of the present invention.
FIG. 2 is an overall perspective view of each of the devices communicating with the separator (crushing / classifying means).

FIGS. 7A and 7B are enlarged schematic views of synthetic paper to be processed in an embodiment of the present invention, wherein FIG. 7A is an example of a synthetic paper by an internal paper method, and FIG. 7B is an example of a synthetic paper by a surface coating method; , (C)
Shows an example of synthetic paper by the surface treatment method.

[Explanation of symbols]

 81 Synthetic paper 82 Small piece to be processed 83 Synthetic resin piece 84 Coating film 120 Cutter mill 121 Cutter mill main body 123 Input port 124 Cutter support 125 Rotary blade 126 Fixed blade 127 Input chamber 128 Crushing chamber 129 Screen 130 Separator 131 Fixed disk 132 Supply port 133 Fixed end plate 134 Fixed pin 135 Peripheral side plate 141 Movable disk 142 Rotating horizontal shaft 143 Bearing 144 Movable pin 151 Screen 152 Outlet 153 Outlet 155 Processing space 156 Drainage space 157 Blower 158 Blower 161 Motor 235 Pipe 236 Pipe 238 Three-way solenoid valve 239 Discharge pipe 240 Recovery tank 250 Collection tank 260 Base layer 262 Surface layer 264 Void 272 White coating layer 282 Altered layer

Claims (2)

[Claims] 1. A method for separating a printing ink coating film from a resin material substrate of waste synthetic paper and recovering the resin material, wherein the waste synthetic paper is crushed into a plurality of small pieces to form small pieces to be treated. A crushing step; applying an impact crushing force to the crushed individual pieces to be processed to peel off the coating film of the printing ink, and crushing and classifying the coating film, and forming a resin for the synthetic paper. Using a material base material as a recovered resin material. 2. A coating film of a printing ink is peeled by applying an impact grinding force to each of the crushed individual pieces to be processed,
2. The method for collecting waste synthetic paper according to claim 1, wherein the step of pulverizing and classifying the coating film and using the resin material base material of the synthetic paper as a recovered resin material is repeated a plurality of times.