JP2005297424A - Paper base recovery method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper base recovery method requiring no organic solvent to hold a work environment and avoiding the occurrence of a finely ground resin to recover a paper base material suitable for recycling. <P>SOLUTION: Resin-coated paper formed by coating both sides of the paper base material with resin films is cleaved into two parts at the part of the paper base material or at the interface between one of the resin films and the paper base material and the cleaved resin material with the paper base material is immersed in a liquid to peel the paper material of the resin material with the paper base material to recover the same. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paper base material recovery method for separating and recovering a paper base material from a resin-coated paper whose both surfaces are coated with a resin material (especially a thermoplastic resin).

  Generally, resin-coated paper coated with a thermoplastic resin for the purpose of waterproofing is used for milk, fruit juice, sake packs, etc. or photographic printing paper. This coated paper is produced by melting and extruding a thermoplastic resin on both sides of the paper substrate to provide a resin film. However, it is used for pack molding and developing photographic paper. Is required to have good adhesion between the resin film and the paper substrate in terms of waterproofness. Therefore, activation treatment such as corona treatment and flame treatment has been applied to the paper base material to improve the adhesive strength with the thermoplastic resin.

  However, if the adhesive strength between the paper substrate and the resin film is strong, when you attempt to collect and reuse used resin-coated paper or resin-coated paper that cannot be produced in the production process, Since it is difficult to separate the material and the resin film, it has been customary to dispose of and incinerate. Therefore, it was extremely uneconomical. In recent years, in view of the ease of handling of resin-coated paper, effective utilization of the paper substrate and the resin film by reusing the paper substrate and separating the paper substrate from the resin-coated paper is desired in recent years. As a result, a technique for separating the paper base material and the resin film and adopting the paper base material again has been put into practical use.

As a technique as described above, for example, a resin-coated paper is directly put into a pulper device, immersed in a high-temperature alkaline solution, disintegrated and recovered as pulp (for example, see Patent Document 1), or resin-coated paper is perforated. And the method (for example, refer patent document 2) which peels by making it contact with the vapor | steam of an organic solvent is proposed. However, in the former, it is recovered in the pulp state, not as a paper base material, but the finely pulverized resin remains in the pulp and becomes a foreign substance when reused, and the latter uses an organic solvent. In addition to the danger of explosion, there is a problem that it is necessary to work in an organic solvent atmosphere.
Japanese Patent Laid-Open No. 62-156378 JP-A-7-148737

As described above, resin-coated paper is widely used in various fields, but a technology that can be reused without causing inconvenience to resin-coated paper that has not been positioned as a product has been established. There is no current situation.
The present invention has been made in view of the above, and is a paper base that does not require an organic solvent, maintains a working environment, avoids the generation of finely pulverized resin, and can recover a paper base material suitable for reuse. It aims at providing the collection | recovery method of material, and makes it a subject to achieve this objective.

Specific means for solving the above problems are as follows.
<1> A resin-coated paper having both sides of a paper base coated with a resin film is split into two in the paper base, and the two resin materials with paper material obtained by splitting are immersed in a liquid. A paper base material recovery method, wherein the paper material of the resin material with paper material is peeled and recovered.
<2> Paper obtained by cleaving a resin-coated paper in which both sides of a paper substrate are coated with a resin film into two at the interface between one of the resin films and the paper substrate, and excluding one of the resin films It is a paper substrate recovery method characterized in that a resin material with a material is immersed in a liquid and the paper material of the resin material with a paper material is peeled and recovered.
<3> The method for recovering a paper substrate according to <1> or <2>, wherein at least one of high-pressure liquid jetting and rubbing treatment is applied to the paper surface of the immersed resinous material with paper, and then peeled off.
<4> The paper substrate recovery method according to any one of <1> to <3>, wherein the liquid contains a surfactant.

  ADVANTAGE OF THE INVENTION According to this invention, the organic solvent is unnecessary, the working environment is maintained, the generation | occurrence | production of finely pulverized resin is avoided, and the recovery method of the paper base material suitable for reuse is provided. be able to. At the same time, the resin film can be recovered.

In the paper base material recovery method of the present invention, the resin-coated paper provided with the resin film on both sides is divided into two parts at the paper base paper part forming the base material or at the interface between the resin film and the paper base paper. The paper material is peeled off from the resin film and recovered by being immersed in a liquid after cleaving.
Hereinafter, the paper substrate recovery method of the present invention will be described in detail.

  According to a first aspect of the paper substrate recovery method of the present invention, two papers are obtained by cleaving a resin-coated paper, in which both sides of the paper substrate are coated with a resin film, into two on the paper substrate. The resin material with paper material is immersed in a liquid, and the paper material of the resin material with paper material is peeled off and collected. In this case, the paper base material sandwiched between the resin films is torn into two parts, and each of the two resin materials with paper material after the cleavage is exposed to the paper material of the exposed paper base material. The paper material is impregnated, and the paper material is peeled from the resin film by applying an external action to the paper material portion (that is, the paper material surface), and the paper material that has been peeled off and floated in the liquid is recovered.

  According to a second aspect of the paper substrate recovery method of the present invention, a resin-coated paper in which both sides of the paper substrate are coated with a resin film is split into two at the interface between one of the resin films and the paper substrate. The resin material with paper material except for one of the resin films is immersed in a liquid, and the paper material of the resin material with paper material is peeled off and collected. In this case, instead of splitting into two at the paper base portion as in the first embodiment, two at the interface between one of the resin films provided on both sides of the paper base and the paper base paper. The paper base is not left on one side of the resin film. Then, the paper material of the paper base material exposed to the resin material with paper material composed of the other resin film and the paper base material is impregnated with a liquid, and the paper material portion (that is, the paper material surface) is externally applied. By applying the action, the paper material is peeled off from the resin film, and the paper material that is peeled off and floats in the liquid is collected.

  The resin of the resin-coated paper may be any one of a thermoplastic resin and a thermosetting resin. For example, when the resin is coated with a thermoplastic resin, when the resin is coated with another resin such as a thermosetting resin other than a thermoplastic resin, such as a resin-coated paper obtained by melt extrusion coating on the surface of a paper substrate The present invention can be applied to any resin-coated paper in which a resin is bonded to the surface of a paper substrate. The thermoplastic resin is preferably a polyolefin resin, and includes low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene such as LLDPE, polypropylene, and the like.

  There are no particular restrictions on the paper substrate, and wood pulp is the main raw material, and if necessary, paper made using synthetic pulp such as polypropylene or synthetic fibers such as nylon or polyester in addition to wood pulp. Is appropriate. The wood pulp may be any of LBKP, LBSP, NBKP, NBSP, LDP, NDP, LUKP, NUKP, and preferably uses more LBKP, NBSP, LBSP, NDP, and LDP with a short fiber content. is there.

  The method of splitting the resin-coated paper in two can be suitably performed by pulling and tearing one and the other of the resin films provided on both sides of the paper substrate in different directions. As a specific example, a configuration in which each of the resin films (for example, an end portion) is gripped or is provided with a plurality of conveying rollers for determining an angle in the tearing direction when the film is elongated, and is torn at the same time as the conveyance. Is mentioned.

  It is desirable to use a liquid that does not contain an organic solvent as the liquid for immersing the two resin materials with paper material that is torn apart from the viewpoint of explosibility and work environment. Or it is an aqueous solution. As an aqueous solution, what contains other components and water miscible organic solvents, such as alcohol, in water can be used. As an aqueous solution containing other components, an aqueous solution containing a surfactant is preferably used. In addition, it is desirable that the content in the case of including the organic solvent is 0.5 to 20% by mass with respect to the mass of the aqueous solution in consideration of explosion prevention.

  When the surfactant is contained, peeling can be easily performed. The surfactant is not particularly limited, and any of nonionic, anionic, cationic, amphoteric, etc. can be used. For example, saponins, sodium sulfonates, polyoxyethylene derivatives, etc. are preferred, Oxyethylene derivatives (for example, Emulgen manufactured by Kao Corporation) are preferred.

  Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, Examples thereof include oxyethylene-oxypropylene block polymers. Examples of the anionic surfactant include fatty acid salts such as sodium oleate and castor oil potash, alkyl sulfate salts such as sodium lauryl sulfate and ammonium lauryl sulfate, alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, and alkylnaphthalenesulfonic acid. Examples thereof include salts, alkane sulfonates, dialkyl sulfosuccinates, alkyl phosphate esters, naphthalene sulfonate formalin condensates, polyoxyethylene alkyl phenyl ether sulfates, polyoxyethylene alkyl sulfates. Examples of the cationic surfactant include alkylamine salts such as laurylamine acetate and stearylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride. Examples of the amphoteric surfactant include lauryl dimethylamine oxide.

  When the surfactant is contained, the content of the surfactant in the aqueous solution depends on the adhesive strength of the paper material to the resin film and the like. -5 mass% is preferable, and 0.2-0.3 mass% is more preferable.

  The liquid temperature of the liquid to be used is preferably set to, for example, about 70 to 100 ° C. as the temperature is high in terms of the releasability of the paper material. However, from the viewpoint of maintaining the peeling efficiency in consideration of handling and energy saving. C. ± .10.degree. C. is preferred.

"
The longer the immersion time in the liquid, the more effective, but from the viewpoint of energy saving, 0.1 to 20 seconds is preferable although it depends on the liquid temperature and the like.

As a method of exfoliating the paper material by applying an external action in the liquid, (1) a method of injecting a liquid or gas at a high pressure on the paper material surface of the immersed resinous material, or (2) A method of rubbing is preferred.
In the case of the method (1), an injection device including an injection nozzle capable of jetting liquid or gas is used, and at least the injection nozzle is disposed in the liquid so that a predetermined pressure is applied to the paper surface. This can be done by spraying.

In this case, the nozzle shape can be arbitrarily configured, such as a nozzle having a circular or rectangular nozzle cross section or a slit nozzle, but a slit nozzle is desirable. In addition, the injection angle depends on the adhesive strength of the paper material on the paper surface of the resin material with paper material, the processing liquid temperature, etc., and an optimum processing condition may be selected depending on the case. It is desirable that the angle be vertical (90 °) or an acute angle. The distance between the nozzle tip of the spray nozzle and the paper surface is preferably as short as possible, and is preferably 1 mm or less. Furthermore, the jet pressure on the paper surface is preferably 0.01 to 0.1 Pa · s / cm ^{2 in} terms of gauge pressure.

  The method (2) can be carried out by arranging a brush or the like at a position that can come into contact with the paper material surface in the liquid so that the paper material surface can be rubbed. As a brush suitable for this case, a brush made of a material such as hair of a animal such as a seal or a pig or a metal wire is effective. In addition to the fixed arrangement of the brush, it is more effective to use a rotatable rotating brush or the like and rotate in the same direction as the transport direction of the resin-coated paper or as a different speed.

  In the process of peeling the paper material as described above, ultrasonic waves may be applied so that the peeling can be performed more quickly and effectively. By applying ultrasonic waves, the adhesion (adhesion strength) of the paper material to the resin film can be reduced and can be easily peeled off. The application of ultrasonic waves may be performed by appropriately selecting conditions, and details will be described later.

  The paper material that has been peeled off as described above will float and exist in the liquid, but this liquid is sent to a waste paper recovery pulper that performs the papermaking process outside, and then re-appears through the papermaking process. Used.

The paper base material recovery method of the present invention can be suitably performed using, for example, a recovery device shown in FIG. The collection method in this case will be described below.
The recovery device 100 shown in FIG. 1 includes a feed roll 10 that feeds untreated resin-coated paper, a front resin film winding roll 11 that winds up one (front side) of the resin film from which the paper material has been peeled, and the other resin. A back resin film take-up roll 12 for taking up the film (back side), and in the transport path between the feed roll 10 and the two take-up rolls 11, 12, a processing liquid 21 is accommodated to store paper material. A treatment tank 20 for separating in liquid is disposed, and the resin-coated paper 1 can be continuously conveyed to perform separation and recovery processing.

  On the upstream side in the transport direction of the processing tank 20 in the transport path from the feed roll 10 to the two winding rolls 11 and 12, the resin-coated paper 1 is cleaved 2 from the support roll 13 and the support roll 13 as a starting point. Tear rolls 14 and 15 for determining the direction are provided so that the transported resin-coated paper can be split at a predetermined angle θ with respect to the two resin articles 2 and 3 with a paper material on the paper base. It has become. The angle θ can be appropriately selected according to circumstances, and is preferably configured to be 90 to 180 °. Further, a roll 9 is provided between the support roll 13 and the delivery roll 10.

  The treatment tank 20 installed on the downstream side in the transport direction of the tearing rolls 14 and 15 stores the treatment liquid 21 and has a plurality of openings through which the resin-coated paper 1 can be inserted on the upper wall. It can be loaded and unloaded. In the processing tank 20, U-turn rolls 16 and 17 are arranged at positions in the processing liquid 21, and spray nozzles 22 and 23 are arranged at positions facing the U-turn rolls 16 and 17, respectively. The treatment liquid can be ejected at high pressure onto the paper material surfaces of the conveyed resin materials 2 and 3 with paper material. The paper material surface is the surface on the side to which the paper material of the resin material with paper material adheres.

  The injection nozzle can be configured in an arbitrary shape, but is preferably a slit nozzle. Further, a nozzle having a circular or rectangular nozzle cross section may be used. In this case, it is particularly effective to arrange a plurality of nozzles with a close interval. Further, the injection angle of the injection nozzle depends on the adhesive strength of the paper material on the paper surface of the resin material with paper material, the processing liquid temperature, and the like, and optimal processing conditions can be selected as appropriate. In particular, the resin-coated paper 1 It is desirable to make an acute angle with the transport surface substantially perpendicularly (90 °) to the transport surface, or toward the direction opposite to the transport direction. The distance between the nozzle tip of the spray nozzle and the resin-coated paper 1 is preferably as short as possible, and is effectively about 1 mm.

  In addition, an ultrasonic generator 24 that generates ultrasonic waves in an aqueous solution is provided at the bottom of the treatment tank 20 so that the paper material can be easily peeled from the resin film. A commercially available ultrasonic generator (for example, UH-600S (manufactured by SMT Co., Ltd.)) can be selected as appropriate, and the output wattage, frequency, maximum amplitude, etc. of the equipment used are the properties of the resin-coated paper. The optimum conditions can be appropriately selected according to the conditions. Further, auxiliary rolls 18 and 19 are also provided between the U-turn roll 16 and the front resin film winding roll 11 and between the U-turn roll 17 and the back resin film winding roll 12, respectively.

  The untreated resin-coated paper 1 is mounted on the feed roll 10 of the recovery device 100, the processing liquid 21 is stored in the processing tank 20, and the temperature is adjusted by a heater (not shown). Then, the resin-coated paper 1 is conveyed at a constant speed, and when it reaches the support roll 13, it is split into two resin materials 2 and 3 with paper material so as to tear in two directions at the paper base portion. The resin materials 2 and 3 with paper material produced by the tearing are further conveyed and immersed in the processing liquid 21, reaching the U-turn rolls 16 and 17 while being absorbed by the paper material surface, and passing there. In the meantime, the treatment liquid 21 is ejected from the ejection nozzles 22 and 23 onto the paper material surfaces of the resin materials 2 and 3 with the paper material, and the paper material is peeled off. After the paper material is peeled off, the resin films of the resin articles 2 and 3 with the paper material are wound around the front resin film winding roll 11 and the back resin film winding roll 12 via the auxiliary rolls 18 and 19, respectively. The paper material that is scraped off and floats in the processing liquid is sent to a waste paper collection pulper (paper making process) installed outside.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof. Unless otherwise specified, “%” is based on mass.

(Example 1)
As the resin-coated paper that is the object to be treated, a long PE-coated paper in which both sides of ^high- quality paper 160 g / m ² (paper base material) are coated with a polyethylene (PE; thermosetting resin) film is wound into a roll. Prepared what was taken.

Next, a recovery apparatus 100 configured as shown in FIG. 1 was constructed.
The recovery device 100 is configured to send out unprocessed PE-coated paper, a feed roll 10, a front PE film winding roll 11 that winds up one (front side) of the PE film from which the paper material has been peeled off, and the other PE film (back side). A water tank that contains an aqueous solution 21 in the transport path between the feed roll 10 and the two take-up rolls 11 and 12 and separates the paper material in the liquid. 20 is arranged so that it can be continuously conveyed to perform separation and recovery processing.
On the upstream side of the transport direction of the water tank 20 in the transport path from the feed roll 10 to the two winding rolls 11 and 12, there are a support roll 13 and two directions for tearing the PE-coated paper from the support roll 13. The tearing rolls 14 and 15 are provided, and the conveyed PE-coated paper 1 is cleaved at a predetermined angle (θ) 120 ° between the two PE films 2 and 3 with paper material on the paper substrate. It has become. Further, a roll 9 is disposed between the support roll 13 and the delivery roll 10.
In the water tank 20, U-turn rolls 16 and 17 are disposed at positions where the aqueous solution 21 is located, and spray nozzles 22 and 23 are disposed at positions facing the U-turn rolls 16 and 17, respectively. The aqueous solution can be sprayed at high pressure onto the paper surface of the PE films 2 and 3 with material. The injection nozzle is adjusted to a direction capable of injection at 90 ° with respect to the paper surface, the distance between the paper surface and the nozzle tip is 1 mm, and the injection pressure on the paper surface is 0.05 Pa · s / g in terms of gauge pressure. cm ² . Further, an ultrasonic generator 24 is provided at the bottom of the water tank 20 so that the paper material can be easily peeled off. Further, auxiliary rolls 18 and 19 are disposed between the U-turn roll 16 and the front resin film winding roll 11 and between the U-turn roll 17 and the back resin film winding roll 12, respectively.

  The unrolled PE-coated paper 1 wound in a roll shape is attached to the delivery roll 10 of the recovery device 100 described above, and Emulgen A60 (manufactured by Kao Corporation; surfactant) is 0.2 in the water tank 20. % Aqueous solution 21 was stored, and the aqueous solution 21 was adjusted to 65 ° C. with a heater (not shown). Then, the PE-coated paper 1 was transported at a transport speed of 10 m / sec, and was split into two PE films 2 and 3 with a paper material so as to be torn in two directions by the support roll 13 at the paper base portion. When the PE films 2 and 3 with paper material that have been cleaved are further conveyed and immersed in the aqueous solution 21, the aqueous solution is absorbed and swelled on the paper material surface, and reaches the U-turn rolls 16 and 17. The aqueous solution 21 was sprayed from the spray nozzles 22 and 23 onto the paper material surfaces of the attached PE films 2 and 3, and the paper material was scraped off. Thereafter, the PE film of the PE film 2 with paper material is wound on the front PE film winding roll 11 via the auxiliary roll 18, and the PE film of the PE film 3 with paper material is wound on the back PE film via the auxiliary roll 19. The paper material wound up on the take-up roll 12 and scraped off and suspended in the aqueous solution 21 is subjected to a certain amount of processing, and then passed through the discharge pipe 25 and is disposed outside as a waste paper collecting pulper (paper making process). ).

(Example 2)
In Example 1, the spray nozzles 22 and 23 are replaced with the rotating brushes 31 and 32 (see FIG. 2), and the paper material peeled off by spraying the aqueous solution is brought into contact with the paper surface of the PE-coated paper. The PE film was wound up and the paper base material was collected in the same manner as in Example 1 except that the paper material was peeled off by scraping. In this example, a stainless steel brush was used as the brush, and the brushes 31 and 32 were rotated (200 rpm) so as to be in the opposite direction to the conveying direction of the PE films 2 and 3 with paper material. FIG. 2 is a diagram showing an example of an apparatus configured similarly except that the spray nozzles 22 and 23 of FIG.

(Example 3)
In Example 1, the operation of tearing the PE-coated paper 1 at the paper base portion is performed by tearing the PE-coated paper 1 in two directions with the support roll 13 at the interface between one PE film and the paper base paper. Example 1 except that the PE film 2 ′ without a paper base material and one PE film 3 with paper material are torn apart and are not ejected from the ejection nozzle 22 in the transport path of the PE film 2 ′. In the same manner as above, the PE film was wound up and the paper substrate was recovered. .

  In any of the above embodiments, the paper base material and PE film constituting the PE-coated paper are recovered as a paper base material and PE material suitable for reuse without generating finely pulverized resin. It was also possible to work in a good working environment without the possibility of explosion or adverse effects on the human body.

It is the schematic which shows an example of the collection | recovery apparatus which collect | recovers a paper base material with the collection | recovery method of the paper base body of this invention which performs high pressure injection. It is the schematic which shows an example of the collection | recovery apparatus which collect | recovers a paper base material with the collection | recovery method of the paper base | substrate of this invention which performs a rubbing process.

Explanation of symbols

1 ... PE coated paper (resin coated paper)
2, 3 ... PE film with paper (resin with paper)
21. Surfactant-containing aqueous solution (treatment solution)
22, 23 ... Spray nozzles 31, 32 ... Stainless steel brush 100 ... Recovery device

Claims (4)

  The paper material is obtained by cleaving a resin-coated paper having both sides of a paper base material coated with a resin film in the paper base material, and immersing the two resin materials with paper material into the liquid. A method for recovering a paper base material, comprising peeling and recovering the paper material of the attached resin.   Resin-coated paper in which both sides of a paper substrate are coated with a resin film, split into two at the interface between one of the resin films and the paper substrate, and one of the resin films is removed A method for recovering a paper base material, comprising: immersing an object in a liquid to separate and recover the paper material of the resin material with paper material.   The method for recovering a paper substrate according to claim 1 or 2, wherein at least one of a high-pressure liquid jetting and a rubbing treatment is applied to the paper material surface of the immersed resin material with paper material, and then peeled off.   The method for recovering a paper substrate according to any one of claims 1 to 3, wherein the liquid contains a surfactant.

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