JP4357585B2 - Separating and collecting plastic and paper from plastic wallpaper - Google Patents

Description

  The present invention relates to a method for separating and collecting plastic and paper from a plastic wallpaper. More specifically, the present invention relates to a plastic wallpaper in which a resin layer is formed on a substrate made of paper, a plastic derived from the resin layer, and a substrate. The present invention relates to a method for separating and collecting paper derived from the paper.

Plastic wallpaper in which a resin layer is formed on a paper substrate is manufactured and used in large quantities as an interior material.
In the manufacturing process and use (at the time of new construction or replacement) of these plastic wallpaper, a large amount of scrap or waste material of the plastic wallpaper is discarded as industrial waste.

  Such plastic wallpaper has a base material and a resin layer that are firmly adhered to each other and cannot be easily peeled off. Paper and plastic are separately collected and recycled from the above scraps or waste materials (resource reuse). It was virtually impossible to do.

  Here, the resin layer of the plastic wallpaper is composed of soft polyvinyl chloride resin (PVC), ethylene-vinyl acetate copolymer resin (EVA), ethylene-methyl methacrylate resin (EMMA), ethylene-ethyl acrylate resin (EEA), It is composed of ethylene-methyl acrylate resin (EMA) or the like, and among these, soft polyvinyl chloride accounts for about 90%.

  Also, foam (foamed resin) is frequently used for the resin layer of plastic wallpaper. A plastic wallpaper having a resin layer made of a foam is lightweight, has a good texture, and is excellent in soundproofing. Here, in order to form a resin layer made of a foam, an organic pyrolytic foaming agent such as azodicarbonamide (ADCA) or 4,4'-oxybisbenzenesulfonyl hydrazide (OBSH) is used.

  At present, these products are hardly recycled (resource reuse), and most of them are incinerated or disposed as landfills as industrial waste.

  In the case of incinerating plastic wallpaper with a resin layer made of vinyl chloride resin, the problem of dioxin that has been attributed to vinyl chloride resin is becoming less of a problem due to recent improvements in incinerator technology. There is concern about the effect of acidic components (hydrochloric acid) on the incinerator caused by hydrogen chloride generated in

In addition, when the scrap or waste material of a plastic wallpaper having a resin layer made of foam is disposed of in landfill, the bulk specific gravity is small and the landfill efficiency is extremely poor.
And among the scraps or scraps of plastic wallpaper to be disposed of in landfill, the paper that made up the base material is decomposed over time with enzymes contained in the soil, but the plastic that made up the resin layer It is preserved in the soil for many years.

  The disposal of plastic wallpaper described above is not an appropriate disposal method from the viewpoint of the global environment. Furthermore, the amount of these wallpaper to be discarded in the future is increasing, and an appropriate response is desired.

(1) Conventionally, a method has been attempted in which a scrap or waste material of plastic wallpaper is pulverized by mechanical means and the plastic and paper are separated by a difference in specific gravity.

  However, according to such a method, it is impossible to completely separate and collect plastic and paper. Paper remains in the collected plastic, and plastic remains in the collected paper.

When the plastic recovered by such a method is reused (for example, mixed with a commercially available plastic raw material), it is long to completely and uniformly disperse the paper inevitably remaining in the recovered plastic. Various troubles occur, such as kneading over time and the need for additional additives. Depending on the mixing ratio of these recovered plastics in which the paper remains, the texture of the finally obtained recycled product (for example, soft vinyl chloride product) and the physical properties of the product become inferior.
On the other hand, paper collected by such a method cannot be recycled as recycled paper because of the remaining plastic.

(2) A method of dissolving and separating a resin layer of a plastic wallpaper with an organic solvent is performed. Furthermore, after the resin layer is swollen with an organic solvent, a method of mechanically scraping the resin layer from the substrate has been introduced (see Patent Document 1).

However, even with such a method, the paper derived from the base material is mixed in the plastic derived from the scraped resin layer, and the plastic derived from the resin layer remains on the base material ( It cannot be completely scraped off) and cannot be completely recycled (effective resource reuse).
Moreover, in such a method, the recovery cost of the used organic solvent is high, and it is necessary to clear the regulation of VOC (volatile organic compound).

(3) Further, as a method for reusing plastic wallpaper, it is pulverized and mixed with sand, and further, a deodorizing agent or the like is added to produce cat sand.

Although such a method is reuse of plastic wallpaper, it is ultimately disposed of as household waste and is not completely recycled (effective resource reuse).
Japanese Patent Laid-Open No. 9-59423

The present invention has been made based on the above situation.
An object of the present invention is to provide a method capable of reliably collecting and collecting plastic and paper from a plastic wallpaper.

  As a result of earnestly examining the recycling (resource reuse) method of plastic wallpaper, which has been considered extremely difficult, the present inventor has focused on the fact that the main component of the paper constituting the wallpaper substrate is cellulose fiber, Cellulose enzyme or cytolytic enzyme is an enzyme capable of degrading cellulose. By decomposing the substrate (paper) into fibers, the substrate is completely separated from the resin layer. As a result, plastic As a result, the present inventors have found that paper can be reliably separated and collected, and the present invention has been completed based on such knowledge.

(1) That is, the separation and recovery method of the present invention is a method for separating and recovering paper and plastic from a plastic wallpaper in which a resin layer is formed on a paper substrate, and is an enzyme capable of decomposing cellulose. (Hereinafter, abbreviated as “cellulose-degrading enzyme”), which comprises contacting the plastic wallpaper with an aqueous solution to separate the substrate from the resin layer in the plastic wallpaper.

(2) The separation and recovery method of the present invention is a method for separating and recovering paper and plastic from a plastic wallpaper in which a resin layer is formed on a paper substrate, wherein the plastic wallpaper is cut into pieces. Is dispersed in an aqueous solution of cellulose-degrading enzyme, and the system is agitated to separate the substrate from the resin layer in the cut pieces.

(3) In the separation and recovery method of the present invention, the step of cutting the plastic wallpaper (hereinafter referred to as “cutting step”) and the obtained cut pieces are dispersed in an aqueous solution of cellulose-degrading enzyme. A step of separating the base material from the resin layer in the cut piece (hereinafter referred to as “layer separation step”) by stirring, and a step of separating and recovering the plastic derived from the resin layer of the cut piece (hereinafter referred to as “the layer separation step”). It is preferable to include a “plastic recovery step”) and a step of collecting and collecting the paper from the paper dispersion after the plastic is separated (hereinafter referred to as “paper recovery step”).

(4) In the fractional collection method of the present invention, the aqueous solution contains 0.005 to 10% by mass of at least one enzyme selected from cellulase, pectinase, hemicellulase, β-glucanase, xylanase, mannase and amylase. It is preferable that it is dissolved in a proportion.

(5) Moreover, it is preferable that the said aqueous solution contains an organic weak acid and the pH of the said aqueous solution is adjusted to acidity.

(6) Moreover, it is preferable that the said aqueous solution contains an alkali and the pH of the said aqueous solution is adjusted to alkalinity.

(7) In the separation and recovery method of the present invention, a new cutting piece is dispersed in an aqueous solution (an aqueous solution after the paper is recovered by filtration) through the layer separation step, the plastic recovery step and the paper recovery step. A layer separation step of separating the base material from the resin layer in the cut piece by agitation processing, a plastic recovery step of separating and collecting plastic derived from the resin layer of the cut piece, and after the plastic is separated It is also possible to repeat the paper collection step of collecting the paper by filtration from the paper dispersion.

(8) In this case, after completion of the paper recovery process, it is preferable to add a weak organic acid or alkali and readjust the pH of the aqueous solution, and then disperse new cut pieces.

(9) In the cutting step of the separation and recovery method of the present invention, it is preferable to cut the plastic wallpaper with a cross-cut large shredder.

(10) The separation and recovery method of the present invention is a method for separating and recovering paper and plastic from a product in which a resin layer is formed on a base material made of paper, wherein the product is added to an aqueous solution of cellulolytic enzyme. It is characterized by including a step of separating the substrate from the resin layer in the product by contacting.

According to the separation and collection method of the present invention, since the base material (paper) can be completely separated from the resin layer constituting the plastic wallpaper, the plastic and paper can be reliably separated and collected.
The separation and recovery method of the present invention is easy, environmentally friendly, and economically advantageous as a recycling method (resource recycling method) of scrap material or waste material of plastic wallpaper.

  According to the fractional recovery method of (5) above, it can be brought into a suitable state for cellulolytic enzymes that maintain activity and stability in acidity, and it is used as a food additive or the like as a pH adjuster. It is further advantageous from the viewpoint of the environment because the organic weak acid is used.

  According to the fractional collection method of (6) above, it is possible to achieve a suitable state for the cellulolytic enzyme that maintains activity and stability in alkalinity.

  According to the fractionated collection method of (7) to (8) above, even if a cellulose-degrading enzyme is not newly added to the aqueous solution for layer separation in the freshly processed cut pieces, Since plastic and paper can be collected separately, repeated treatment is possible, which is further advantageous economically.

  According to the fraction recovery method of (9) above, the fraction recovery in the plastic recovery step and the paper recovery step can be performed more easily.

  The plastic recovered by the separation and recovery method of the present invention has physical properties required for a reusable plastic by washing and drying, and therefore, it is recycled as a recyclable (resource reusable) material. can do.

The paper recovered by the separation and recovery method of the present invention is pure pulp containing no plastic, and can be reused as a recycled paper or wallpaper base material.
In addition, the fibrous paper separated from the resin layer in the layer separation step is decomposed by cellulose-degrading enzyme and decomposed to sugar (C _n H _2n O _n ) by using saccharifying enzyme, and then It is also possible to convert to an organic compound having a high added value (for example, ethyl alcohol, glycerin, acetone, butanol, isobutanol, and further isobutylene, diisobutylene, isooctane) using fermentation by fermentation yeast.

  In addition, since the original fiber of the paper recovered by the separation and recovery method of the present invention is refined by cellulolytic enzyme, the remaining cellulolytic enzyme is steamed at a high temperature, and further mechanically Nanofibers can also be formed by defibrating treatment.

Hereinafter, the fraction collection method of the present invention will be described in detail.
The separation and recovery method of the present invention requires a layer separation step described in detail below, and preferably includes a cutting step as a pre-process, and includes a plastic recovery step and a paper recovery step as post-steps.

<Cutting process>
The cutting step in the separation and recovery method of the present invention is a step of cutting the plastic wallpaper to be recycled into an appropriate size.
The shape of the cut piece obtained through the cutting step is not particularly limited, but a quadrangle, particularly a square is preferable.

A suitable size of the cut piece obtained through the cutting process is, for example, 1 cm from the viewpoint of facilitating the collection of plastic and paper and maintaining the quality of the collected paper, although it depends on the scale of the processing equipment and the stirring method. ² (for example, 1 cm × 1 cm) or more is preferable, more preferably 1 to 2,500 cm ² , and particularly preferably 1 to 1,000 cm ² .

  When the size of the cut pieces is too small (for example, when pulverized by a pulverizer), it becomes difficult to separate and collect these in the plastic recovery process and the paper recovery process, and the collected paper is mixed with plastic. Therefore, the quality is reduced.

The cutting method is not particularly limited, but it is preferable to cut with a large cross-cut type shredder, which improves the drying efficiency of the collected plastic (cut pieces), and thus the entire process. Increases efficiency.
In addition, a cutting process can be skipped when the plastic wallpaper is already cut into a suitable size as a scrap or waste material.

<Layer separation process>
The layer separation step in the separation and recovery method of the present invention includes, for example, dispersing the cut pieces obtained in the cutting step in an aqueous solution of cellulose-degrading enzyme, and stirring the system, whereby the resin layer in the cut pieces is obtained. Is a step of separating the base material from (decomposing the paper constituting the base material and separating it from the resin layer).

The cellulolytic enzyme used in the layer separation step is not particularly limited as long as it is an enzyme having an activity of degrading natural cellulose, which is an insoluble substrate, and cell wall (membrane) lytic enzyme agent, cytolytic enzyme agent, etc. What is called can be used suitably.
Examples of the cellulolytic enzyme include cellulase, pectinase, hemicellulase, β-glucanase, xylanase, mannase and amylase.

  These cellulose-degrading enzymes (cellulases) are commercially available as fiber modifiers and fiber treatment agents. Commercially available cellulolytic enzymes include “Cellulase GODO TCL” (manufactured by Godo Seisei Co., Ltd.), “Cellulase“ Onozuka ”3S” (manufactured by Yakult Yakuhin Kogyo Co., Ltd.), “Entilon CM-40L” (Nakto Kasei Kogyo Co., Ltd.) Company-made), “Entilon GK-200” (manufactured by Nitto Kasei Kogyo Co., Ltd.), “Dolylase 20” (manufactured by Kyowa Hakko Co., Ltd.), “Cellulase A“ Amano ”3” (Amano Enzyme Co., Ltd.), etc. be able to.

  The concentration of the cellulolytic enzyme in the aqueous solution is usually 0.005 to 10% by mass, preferably 0.05 to 5% by mass.

  The hydrogen ion concentration of the aqueous solution varies depending on the type of cellulose-degrading enzyme in the aqueous solution (specifications of commercially available products), but the hydrogen ion concentration index (pH) is 3 to 10 from the viewpoint of maintaining the activity and stability of cellulose degradation. It is preferable that it is the range of these. The pH value can be appropriately adjusted by adding an acid or an alkali.

  As acids used to adjust the hydrogen ion concentration index (pH) of aqueous solutions to acidity (<7), inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid can be used, but as food additives, etc. Use of the weak organic acid used is preferable from the viewpoint of the environment.

Examples of the weak organic acid include citric acid, tartaric acid, malic acid, acetic acid, oxalic acid, succinic acid, and gluconic acid.
The density | concentration of the organic weak acid used in order to adjust pH of aqueous solution, for example in the range of 4-5 shall be 0.0005-5 mass% normally.

  As the alkali used to adjust the hydrogen ion concentration index (pH) of the aqueous solution to alkalinity (7 <), it is possible to use a base such as sodium hydroxide or potassium hydroxide. It is preferable to use a weak alkali that can be added to food.

Examples of the weak alkali include salts such as sodium bicarbonate, ammonium bicarbonate, sodium tartrate, potassium sodium tartrate, sodium phosphate, sodium citrate, sodium acetate and the like.
The concentration of the alkali used to adjust the pH of the aqueous solution to a range of, for example, 8 to 10 is usually 0.001 to 10% by mass, preferably 0.01 to 5% by weight.

The amount (preparation amount) of the cut pieces to be dispersed in the aqueous solution can be appropriately adjusted depending on the expansion ratio of the resin layer.
Here, the charging amount of the cut pieces of the wallpaper (non-foamed product) having the non-foamed resin layer is 12 to 18 parts by mass with respect to 100 parts by mass of the aqueous solution.
Moreover, the preparation amount of the cut piece of the wallpaper (low foaming product) which has a low foaming resin layer (foaming ratio = 2-4 times) shall be 10-15 mass parts with respect to 100 mass parts of aqueous solution.
Moreover, the preparation amount of the cut piece of the wallpaper (high foaming product) which has a highly foamed resin layer (foaming ratio = 5-8 times) shall be 8-12 mass parts with respect to 100 mass parts of aqueous solution.

By stirring the aqueous solution in which the cut pieces of plastic wallpaper are dispersed (the dispersion of the cut pieces), the paper constituting the base material is decomposed, and the base material (paper decomposed into fibrous forms) is separated from the resin layer. Is done.
Examples of the agitation treatment method include a method of mechanically agitating the dispersion of the cut pieces accommodated in the treatment tank with a stirring blade, a method of agitating the water with a water pump, and the like.

  The temperature at the time of stirring (treatment temperature) varies depending on the type of cellulose-degrading enzyme in the aqueous solution (specifications of commercially available products), but is preferably 20 to 70 ° C. from the viewpoint of maintaining the activity of the cellulose-degrading enzyme.

  The agitation time (treatment time) includes the type of plastic composing the cut resin layer, the degree of polymerization, the type and amount of plasticizer used, foamability and expansion ratio, the degree of embossing, the type and amount of cellulolytic enzyme Although it depends on the treatment temperature and the like, the separation of the base material from the resin layer of the cut pieces can be completed usually in 2 to 4 hours.

  In the layer separation step, it is preferable to perform mechanical stirring while applying ultrasonic vibration to the dispersion of the cut pieces. Here, the frequency of the ultrasonic vibration is preferably 28 to 100 kHz. By combining mechanical agitation and application of ultrasonic vibration, the cavitation action can increase the processing amount of cut pieces and shorten the processing time, and improve the separation efficiency between the resin layer and the base material layer. Can be improved.

By the layer separation process, the base material (paper decomposed into a fibrous form) is completely separated from the resin layer.
The resin layer in the cut piece becomes a plastic piece in which the shape of the cut piece before processing is maintained, and the trace of the base material (paper) is not recognized in this plastic piece (contact surface with the base material).
On the other hand, the base material in the cut piece is dispersed in an aqueous solution in a state of being decomposed into a fibrous form to constitute a suspension.

<Plastic recovery process>
The plastic recovery step in the separation and recovery method of the present invention is a step of separating and recovering the plastic (piece) derived from the resin layer, which remains after the base material (paper) is separated from the cut pieces.
Specifically, using a mesh-sized net capable of collecting only plastic (pieces), plastic can be collected separately according to a conventional method.
The mesh size of the net can be selected as appropriate according to the size of the cut pieces that have been loaded.
Further, when the size of the cut piece is large, it can be collected (taken out of the paper dispersion) without using a net or the like.

<Paper collection process>
The paper recovery step in the separation and recovery method of the present invention is a step of recovering the paper from the paper dispersion after the plastic is separated.
Specifically, a fiber separator is collected by centrifuging an aqueous solution (paper dispersion) in which fiber paper is dispersed using a centrifuge capable of scraping. Here, a non-woven fabric or glass fiber can be suitably used as the filter cloth.

  As described above, the cellulose-degrading enzyme is contained in the aqueous solution after the paper is collected. Therefore, new cut pieces can be charged into this aqueous solution, and the separation and recovery method (layer separation step, plastic recovery step, and paper recovery step) of the present invention can be performed again.

Further, the pH of the aqueous solution may be readjusted when a new cut piece is charged.
In this way, plastics and paper can be separated and recovered from the cut pieces without newly adding a cellulolytic enzyme to the aqueous solution for layer separation in the newly processed cut pieces. The process can be repeated, which is more advantageous economically.
Needless to say, when the separation / recovery (layer separation step / plastic recovery step / paper recovery step) is performed again, cellulose degrading enzyme and water which are inevitably lost may be replenished.

  As described above, the separation and recovery method of the present invention is not a landfill process or an incineration process that is currently mainly performed as a recycling (resource reuse) process for discarded wallpaper, but is easy and environmentally friendly. This is an economically advantageous separation treatment method.

  The plastic separated and collected by the separation and collection method of the present invention can be used without any trouble at a free ratio to the corresponding plastic.

  Furthermore, when the plastic separated and collected by the separation and collection method of the present invention is EVA, EMMA, EEA, EMA, etc., it is necessary when manufacturing the product by calendering or extrusion (T-die method). Accordingly, a part of them can be reused by adding foaming agents and other additives.

  Since the paper separated and collected by the separation and collection method of the present invention does not contain plastic derived from the resin layer, it can be used as recycled paper for various applications and reused as a base material for plastic wallpaper. It is also possible.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In the following, “parts” and “%” mean “parts by mass” and “% by mass”.

<Example 1>
(1) Cutting process:
A plastic wallpaper (manufactured by Takeno Co., Ltd.) having a resin layer made of polyvinyl chloride was cut with a large cross-cut type shredder to obtain a 0.4 cm × 4 cm cut piece.

(2) Layer separation step:
By dissolving 10 g of cellulase commercial product “Entilon CM-40L” (manufactured by Nitto Kasei Kogyo Co., Ltd.) and 0.01 g of citric acid in 1 L of water, an aqueous solution of pH 4.3 (cellulase concentration = 1%) was obtained. Prepared.
The obtained aqueous solution was heated to 50 ° C. in a treatment tank, and 100 g of the cut pieces obtained in the cutting step were dispersed therein and mechanically stirred at 50 ° C. for 2 hours.
As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.

(3) Plastic recovery process:
From the plastic (piece) and paper dispersion obtained through the layer separation step, the plastic (plastic piece in which the shape of the cut piece was maintained) was separated and collected by a 5-mesh net. This was simply washed with water and sufficiently dried to obtain 80.5 g of plastic (soft polyvinyl chloride) derived from the resin layer.

  In 80 parts of the plastic (soft polyvinyl chloride) thus obtained, 0.5 part of barium stearate is uniformly dispersed, and this is kneaded with a 6-inch test roll (surface temperature 160 ° C.) for 5 minutes. By doing so, a soft polyvinyl chloride sheet having a thickness of 3 mm and containing no fibrous substance (paper) could be obtained.

  In addition, a mixture of 100 parts of a vinyl chloride resin having a degree of polymerization of 1100, 50 parts of diisononyl phthalate (DINP), and 2 parts of a barium-zinc liquid stabilizer was added to the plastic (soft polychlorinated product) obtained by the plastic recovery process. (Vinyl) 30 parts are mixed, and this mixture is kneaded with a 6-inch test roll (surface temperature 170 ° C.) for 5 minutes to obtain a uniform poly (0.5 mm thick) containing no fibrous substance (paper). A vinyl chloride sheet could be obtained.

(4) Paper collection process:
The paper dispersion (suspension) obtained through the plastic recovery process was filtered through a 24 cm Buchner filter, and the paper was filtered and recovered through a synthetic fiber filter cloth. By sufficiently drying this, 18.5 g of fiber paper derived from the substrate was obtained. The pH of the aqueous solution after separating the paper was 5.0.

<Example 2>
A plastic provided with a resin layer made of polyvinyl chloride in an aqueous solution obtained by dissolving 10 g of cellulase commercial product “Entilon CM-40L” (manufactured by Toto Kasei Kogyo Co., Ltd.) and 0.01 g of citric acid in 1 L of water. Disperse 120 g of wallpaper (manufactured by Takeno Co., Ltd.) (0.4 cm × 4 cm), and charge this into a 1.2 L ultrasonic generator (Tokyo Glass Instrument Co., Ltd., FU-2H type). While applying ultrasonic vibration (28 kHz, output 55 W), mechanical stirring was performed at 50 ° C. for 1.5 hours.
As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.
Next, the same plastic recovery process as in Example 1 (3) was performed to obtain 95 g of plastic (soft polyvinyl chloride) derived from the resin layer. Thereafter, the same paper recovery process as in Example 1 (4) was performed to obtain 22 g of fiber paper derived from the substrate.
As described above, in the layer separation step, by increasing the mechanical stirring while applying ultrasonic vibration, it is possible to increase the charged amount (processing amount) of the cut pieces and shorten the stirring time (processing time). did it.

<Example 3>
After adding 0.002 g of citric acid to the aqueous solution (pH = 5.0) after completion of the paper recovery process of Example 1 (4), the pH is adjusted to 4.3 again, and then 100 g of new cut pieces are dispersed. Then, the layer separation step was performed in the same manner as in Example 1 (2). As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.
Next, the same plastic recovery process as in Example 1 (3) was performed to obtain 78 g of plastic (soft polyvinyl chloride) derived from the resin layer. Then, the paper recovery process similar to Example 1 (4) was implemented, and the fiber-state paper 21g derived from a base material was obtained.

In addition, water and water slightly lost by evaporation, etc. are replenished. Cellulase is replenished as necessary, and citric acid is added to adjust the pH. When the separation step, the plastic recovery step, and the paper recovery step) were repeated 10 times, as in Example 1, the plastic and paper could be reliably collected separately.
In addition, when the content of the metal in the aqueous solution was measured after completion of the fractional collection three times, barium was 14 ppm, zinc was 50 ppm, and calcium was 634 ppm.
Barium and zinc are derived from the stabilizer contained in the resin layer (vinyl chloride resin), and calcium is derived from the filler (calcium carbonate) contained in the resin layer. It is done.

<Example 4>
A highly foamed wallpaper made of soft polyvinyl chloride (commercially available product without back paste treatment) was cut with a large cross-cut type shredder to obtain a cut piece of 0.4 cm × 4 cm.
On the other hand, 20 g of “Cellulase“ Onozuka ”3S” (manufactured by Yakult Pharmaceutical Co., Ltd.), 30 g of “Entilon CM-40L” (manufactured by Nitto Kasei Kogyo Co., Ltd.), and 0.01 g of tartaric acid are dissolved in 1 L of water. Was used to prepare an aqueous solution having a pH of 5.0 (cellulase concentration = 5%).
The obtained aqueous solution was heated to 50 ° C. in the treatment tank, and 80 g of the above-mentioned cut pieces obtained by cutting the highly foamed wallpaper were dispersed therein and mechanically stirred at 50 ° C. for 3 hours. It was. As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.
Subsequently, the same plastic recovery process as Example 1 (3) was implemented, and the plastic 64g derived from the resin layer was obtained. The obtained plastic did not contain any fibrous material (paper).
Thereafter, the same paper collecting step as that of Example 1 (4) was performed to obtain 16 g of fiber-like paper derived from the base material.

<Example 5>
A plastic wallpaper (made by Toei Co., Ltd.) having a resin layer made of ethylene-vinyl acetate copolymer resin (EVA) was cut with a large cross-cut shredder to obtain a 0.4 cm × 4 cm cut piece. .
On the other hand, 0.5 g of “Enthylon CM-40L” (manufactured by Nitto Kasei Kogyo Co., Ltd.) and 0.005 g of citric acid were dissolved in 1 L of water to give a pH 3.5 aqueous solution (cellulase concentration = 0.05%). ) Was prepared.
The obtained aqueous solution was heated to 50 ° C. in the treatment tank, and 100 g of the above-mentioned cut pieces were dispersed therein, and mechanical stirring was performed at 50 ° C. for 3 hours.
As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.
Next, the same plastic recovery process as in Example 1 (3) was performed to obtain 69 g of plastic derived from the resin layer. The obtained plastic did not contain any fibrous material (paper).
Then, the same paper collection | recovery process as Example 1 (4) was implemented, and the fiber-state paper 19g derived from a base material was obtained.

  30 parts of plastic (EVA) derived from the resin layer, separated and collected as described above, and sufficiently dried, 70 parts of commercially available EVA resin, and a lubricant for olefin “AX-510” (manufactured by Daikyo Kasei Kogyo Co., Ltd.) ) 0.3 parts thoroughly mixed and kneaded for 5 minutes with a 6-inch test roll (surface temperature 150 ° C.), so that the thickness of a soft sensation containing no fibrous substance (paper) is 0.3 mm. A uniform EVA film could be obtained.

In addition, 30 parts of plastic (EVA) derived from the resin layer, separated and collected as described above, and 1.3 parts of pyrolytic foaming agent “AZ-30501” (manufactured by Otsuka Chemical Co., Ltd.) , 0.1 part of sodium perchlorate (50% aqueous solution) and 0.2 part of sodium dodecylbenzene sulfonate were blended, mixed well, and mixed with a 6 inch test roll (surface temperature 85 ° C.). By kneading for a minute, a uniform EVA film having a thickness of 0.17 mm was obtained. This EVA film was laminated on a flame retardant paper for wallpaper, and subjected to hot pressing under conditions of 120 ° C. and 100 kg / cm ² for 5 minutes to prepare a test sample.

<Reference example>
100 parts of commercially available EVA resin, 60 parts of calcium carbonate “Whiteon H” (manufactured by Shiraishi Kogyo Co., Ltd.), 20 parts of titanium oxide “R-103” (manufactured by DuPont), and pyrolytic foaming agent “AZ-30501” 4 parts (made by Otsuka Chemical Co., Ltd.), 3 parts zinc stearate, 0.3 part sodium perchlorate (50% aqueous solution), and 0.6 part sodium dodecylbenzenesulfonate were blended sufficiently. And kneaded for 5 minutes with a 6-inch test roll (surface temperature 85 ° C.) to obtain a uniform EVA film having a thickness of 0.17 mm. This EVA film was laminated on a flame retardant paper for wallpaper, and subjected to hot pressing under conditions of 120 ° C. and 100 kg / cm ² for 5 minutes to prepare a test standard sample.

  The test sample prepared in Example 5 and the test standard sample prepared in the reference example were each cut into a size of 5 cm × 5 cm, and each was performed for 50 seconds in a gear oven set at 210 ° C. The samples were heated and foamed for 60 seconds, 70 seconds, and 80 seconds, and the respective foaming ratios and states of the foamed cells were visually compared and judged to be identical. Moreover, the value of a color measuring machine was also equivalent, and the difference was not recognized.

<Example 6>
(1) Cutting process:
A plastic wallpaper provided with a resin layer made of polyvinyl chloride was cut to obtain a cut piece of 10 cm × 10 cm.

(2) Layer separation step:
An aqueous solution having a pH of 8 was prepared by dissolving 25 g of a commercially available cellulase product “Entilon GK-200” (manufactured by Toto Kasei Kogyo Co., Ltd.), 2 g of sodium hydroxide, and 15 g of sodium citrate in 5 L of water.
In a treatment tank in which this aqueous solution (cellulase concentration = 0.5%) was stored, 250 g of the cut pieces obtained in the cutting step were charged and mechanically stirred at room temperature for 2 hours.
As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer.

(3) Plastic recovery process:
From the plastic (piece) and paper dispersion obtained through the layer separation step, the plastic (plastic piece in which the shape of the cut piece was maintained) was fractionated and collected. This was simply washed with water and sufficiently dried to obtain 195 g of plastic (soft polyvinyl chloride) derived from the resin layer.

(4) Paper collection process:
The paper dispersion obtained through the plastic recovery step was filtered with a 24 cm Buchner filter, and the paper was filtered off with a synthetic fiber filter cloth and recovered. By sufficiently drying this, 50 g of fiber paper derived from the substrate was obtained.

  As shown in this example, by appropriately selecting a cellulolytic enzyme, plastic and paper can be reliably separated and collected even if a cut piece is charged into a weak alkaline aqueous enzyme solution.

<Example 7>
(1) Cutting process:
A plastic wallpaper (Nihon Vinyl Kogyo Co., Ltd.) provided with a resin layer made of polyvinyl chloride was cut with a hydraulic cutting machine (Marusei Seisakusho Co., Ltd.) to obtain a cut piece of about 20 cm × about 20 cm.

(2) Layer separation step:
A double-structured processing tank (capacity) consisting of an outer tank (tank body) equipped with a hot water heating jacket and a bottom drain and an inner tank (tubular body) made of a perforated plate with a number of through-holes having a diameter of 2 mm. In 600 L), 2.5 kg of cellulase commercially available product “Enthylon CM-40L” (manufactured by Nitto Kasei Kogyo Co., Ltd.) and 0.2 kg of citric acid are dissolved in 400 L of water to obtain an aqueous solution of pH 4.6 ( Cellulase concentration = 0.625%) was prepared.
Next, 15 kg of the cut pieces obtained in the cutting step were charged into this treatment tank, and mechanical stirring was performed for 2 hours while maintaining the temperature of the aqueous solution at 45 ° C.
As a result, the base material (paper) constituting the cut pieces was suspended in a state of being decomposed into fibers and separated from the resin layer. The pH at the end of the separation was 5.0.

(3) Paper collection process:
The dispersion obtained in the layer separation process is placed in the centrifuge (manufactured by Asahi Seisakusho Co., Ltd.) equipped with a synthetic fiber filter cloth installed at the bottom of the processing tank from the bottom drainage port of the processing tank (outer tank). Supplied. At this time, since the plastic piece maintaining the shape of the cut piece could not pass through the perforated plate, it remained in the inner tank. In addition, adhesion of paper was recognized by a part of plastic in an inner side tank.

The paper dispersion supplied to the centrifuge is filtered, the paper is filtered off with a synthetic fiber filter cloth, and the plastic pieces remaining in the inner tank are washed with an aqueous solution that has passed through the filter cloth. The later aqueous solution was introduced into a centrifuge and filtered again, and the paper (paper recovered by washing) was filtered off with a filter cloth.
Here, in the filtration process by the centrifuge, the rotation was performed at a rotation speed of 1,380 rpm for 15 minutes. The time required for the separation was 20 minutes.
The paper recovered in this manner contained about 43% aqueous solution. Next, this was sufficiently dried to obtain about 3 kg of fibrous paper derived from the substrate.

(4) Plastic recovery process:
The plastic piece remaining in the treatment tank (inner tank) was washed with water and then taken out, and sufficiently dried to obtain 11.8 kg of plastic (soft polyvinyl chloride) derived from the resin layer.

Claims (8)

A method of separating and collecting paper and plastic from a plastic wallpaper in which a resin layer is formed on a paper substrate,
Cutting the plastic wallpaper in an aqueous solution of an enzyme in which at least one enzyme selected from cellulase, pectinase, hemicellulase, β-glucanase, xylanase, mannase and amylase is dissolved in a proportion of 0.005 to 10% by mass A method for separating and recovering plastic and paper from a plastic wallpaper, comprising the step of separating the substrate from the resin layer in the cut piece of the plastic wallpaper by contacting the substrate. A method of separating and collecting paper and plastic from a plastic wallpaper in which a resin layer is formed on a paper substrate,
The cut pieces of the plastic wallpaper is dispersed in an aqueous solution of the enzyme, by stirring process this system, in claim 1, characterized in that it comprises a step of separating the substrate from the resin layer in the cut piece The separation collection method as described . Cutting the plastic wallpaper;
The resulting cut piece is dispersed in an aqueous solution of the enzyme, by stirring process this system, and separating the substrate from the resin layer in the cut pieces,
A step of separating and collecting plastics derived from the resin layer of the cut pieces;
The method according to claim 2, further comprising a step of filtering and collecting the paper from the paper dispersion after the plastic is sorted. The aqueous organic weak acid is contained in, fractional recovery method according to any one of claims 1 to 3 pH of the aqueous solution is characterized in that it is adjusted to be acidic. The method according to any one of claims 1 to 3 , wherein the aqueous solution contains an alkali, and the pH of the aqueous solution is adjusted to be alkaline. A step of separating the substrate from the resin layer in the cut pieces by dispersing new cut pieces in the aqueous solution after the paper is collected by filtration and stirring the system; and the resin layer of the cut pieces a step of separately collected plastics derived from, claims 3 to 5 the plastic and performing repeatedly to the steps of filtration recovery of the paper from the dispersion of the paper in after being fractionated The fraction collection method according to any one of the above. 7. The method according to claim 6 , wherein after the step of collecting and collecting the paper by filtration, an organic weak acid or alkali is added and the pH of the aqueous solution is readjusted, and then the new cut pieces are dispersed. . The method of separating and collecting according to any one of claims 3 to 7 , wherein in the step of cutting the plastic wallpaper, the plastic wallpaper is cut with a large cross-cut type shredder.