JP2023163955A - Method for separating and recovering laminated film - Google Patents

Abstract

To provide a method for efficiently separating and recovering a resin substrate from a laminated film without preventing exposure of separation layers of shredded surfaces.SOLUTION: A method for separating and recovering a laminated film having at least a resin substrate layer and a separation layer comprises: (1) shredding step for shredding the laminated film while cooling the same with water cooled to liquid temperature of 50°C or lower using cooling means to obtain shredded articles; (2) separation step for immersing the shredded articles into a separation liquid to separate the resin substrate layer; and (3) recovering step for recovering the separated resin substrate layer.SELECTED DRAWING: None

Description

The present invention relates to a method for separating and recovering a laminated film having at least a resin base layer and a release layer in contact with the resin base layer.

In recent years, packages, plastic bottles, and other plastic products made from plastic films have become a problem as a cause of environmental pollution, and regulations on waste plastics have become stricter. For example, when these plastic products are discarded or dumped as marine debris, they decompose in the seawater and become submicron-sized fragments (microplastics) that float in the seawater. If such plastics are ingested by marine organisms such as fish, they may become concentrated within the organisms, and there is concern that this may affect the health of seabirds and humans who consume the marine organisms as food.

Examples of the plastic products include food packaging packages using plastic base materials. The laminated film used for the package is generally made of various plastic base materials such as polyester (PET) base material, nylon (NY) base material, polypropylene (PP) base material, etc., as well as gravure ink, flexo ink, etc. The printing layer is provided with printing ink. The laminated film may be further bonded to a sealant base material via an adhesive or the like, and can be appropriately selected from laminated films with a wide variety of configurations depending on the purpose and contents.

As an attempt to solve environmental problems caused by plastics, for example, Patent Document 1 discloses recovering a sealant base material from a laminated film by using an adhesive having alkali-eliminating properties. However, separation of such a laminated film is greatly influenced by the contact situation between the release layer and the alkaline solution, and how exposed the release layer is from the end face of the laminated film is important.

As a shredding method used in the recycling process of plastic waste materials etc. that does not involve film separation, for example, Patent Document 2 discloses a shredding method that uses a shredding machine with a fixed blade and a rotating blade, and uses A method of dry shredding is described.
Further, for example, Patent Document 3 describes that by crushing waste plastics such as used bottles and washing them with water at the same time, it is possible to efficiently wash dirt on the inner and outer surfaces of the bottles in a short time.

As a method for separating and recovering laminated films, for example, Patent Document 4 describes a recycling system in which the laminated body is separated into single layers while being crushed in water or a cleaning agent.

International Publication No. 2020/111226 Japanese Patent Application Publication No. 10-137615 Japanese Patent Application Publication No. 2002-200433 International Publication No. 2021/230033

However, in a laminated film including a plastic base material, there is a problem that the plastic base material fuses due to the heat during shredding and blocks the cross section, so that the release layer is not exposed. Therefore, in the method described in Patent Document 2, the desorption layer is not exposed and cannot come into contact with the alkaline solution, and the separation efficiency of the laminated film is significantly reduced.
Furthermore, the method described in Patent Document 3 is aimed at cleaning and crushing thick waste plastics such as PET bottles for reuse, and does not describe shredding the laminated film. . Furthermore, Patent Document 3 aims to clean and remove stains such as sugar adhering to the surface of waste plastic, and it is said that the higher the temperature of the cleaning water, the better the cleaning efficiency. Conceivable. Furthermore, since the method of Patent Document 3 does not include the step of desorbing the ink layer, adhesive layer, etc., and the step of recovering the base material after desorption, the obtained recycled plastic has low mechanical properties or has a dark color. Therefore, the scope of recyclable applications is limited.
In addition, the method described in Patent Document 4 performs separation using the shear force of crushing, so in order to achieve separation performance, it is necessary to increase the residence time and stirring force in the stirring section of the crushing device. Under such strong crushing conditions, a large amount of fine pieces of laminated film are generated due to excessive shearing and dispersed in the water, making it difficult to separate them from ink pieces and cleaning fluid and collect them later. There is an issue of becoming. In addition, in the method described in Patent Document 4, ink pieces, adhesive pieces, etc. generated during crushing and separation adhere and accumulate in the crushing device and on the resin base material, and as in Patent Document 3, the resulting recycled plastic is There is a problem that quality deteriorates. Furthermore, Patent Document 4 states that in order to efficiently peel off and remove the ink layer and the like provided on the laminate, it is preferable that the liquid temperature of the water or cleaning agent used be higher.

That is, Patent Document 1 does not describe the details of the method for shredding the laminated film, and the laminated film described in Patent Document 1 is not described in Patent Documents 2 to 4 assuming an actual recycling process. If a large amount of shredded plastic is shredded using the conventional method, a laminated film that cannot be separated without exposing the release layer may be generated, or ink fragments generated during shredding may adhere to and accumulate on the base material, resulting in recycled plastic. There is a problem that the quality of the product deteriorates. Then, by cooling with water whose liquid temperature is adjusted to 50°C or less using a cooling means, fusion of the resin base material layer in the cross section during shredding is suppressed, and it is efficiently peeled from the release layer. A highly practical method for separating and recovering laminated films has not yet been reported.

That is, an object of the present invention is to provide a method for efficiently separating and recovering a resin base material without preventing the exposure of a thin cross-sectional detachment layer.

A method for separating and recovering a laminated film according to one aspect of the present invention is a method for separating and recovering a laminated film having at least a resin base layer and a release layer, and includes the following steps (1) to (3). It is characterized by
(1) A shredding step in which the laminated film is shredded while being cooled with water at a liquid temperature of 50° C. or lower using a cooling means to obtain shredded products. (2) A shredding step in which the shredded material is immersed in a desorption liquid. , separation step of separating the resin base layer (3) recovery step of recovering the separated resin base layer

A method for separating and recovering a laminated film according to one aspect of the present invention is characterized by having the following step (4) between the step (1) and the step (2).
(4) Washing and filtration step in which the shredded material is washed with water to remove fine pieces.

The method for separating and recovering a laminated film according to one aspect of the present invention is characterized in that the step (4) involves filtering using a filter screen.

A method for separating and recovering a laminated film according to one aspect of the present invention is characterized in that the mass of water used in the shredding step is 2 to 500 times the mass of the laminated film.

A method for separating and recovering a laminated film according to one aspect of the present invention is characterized in that the release layer is a layer containing a compound having an acidic group.

A method for separating and recovering a laminated film according to one aspect of the present invention is characterized in that the release layer is a layer containing a water-soluble resin.

In the method for separating and recovering a laminated film according to one aspect of the present invention, the laminated film has a partial structure including a resin base layer, a primer layer, and an ink layer in this order, and the primer layer is a release layer. It is characterized by

In the method for separating and recovering a laminated film according to one aspect of the present invention, the laminated film has a partial structure in which two resin base layers are laminated with an adhesive layer interposed therebetween, and the adhesive layer is a release layer. It is characterized by

The laminated film separation and recovery method according to one aspect of the present invention is characterized in that the laminated film has a partial structure including a resin base layer and an ink layer in this order, and the ink layer is a release layer. shall be.

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide a method for efficiently separating and recovering a resin base material in a laminated film having at least a resin base material layer and a release layer without preventing exposure of the release layer with a thin cross section. .

The present invention is a method for separating and recovering a laminated film having at least a resin base layer and a release layer, the method comprising: sequentially performing the steps (1) to (3) below. This is a collection method.
(1) A shredding step in which the laminated film is shredded while being cooled with water at a liquid temperature of 50° C. or lower using a cooling means to obtain shredded products. (2) A shredding step in which the shredded material is immersed in a desorption liquid. , Separation step of separating the resin base material layer (3) Recovery step of recovering the separated resin base material layer. It is possible to prevent the cross section of the release layer from being covered by the fusion of the resin base layer. Then, by suitably exposing the release layer in the shredded laminated film, the resin base material and the release layer can be efficiently separated and the resin base material can be recovered.
Also, by performing step (1) and step (2) sequentially, that is, performing them separately rather than simultaneously, impurities such as ink pieces generated in step (1) may be mixed into step (2). can be prevented. Thereby, it is possible to prevent impurities such as ink particles from adhering to and accumulating on the resin base material, and it is possible to obtain recycled plastic of excellent quality. Furthermore, since the resin base material layer can be separated and recovered without making the laminated film excessively fine, the separation and recovery properties of the resin base material can be improved.
The present invention will be described in detail below, but these are just examples of embodiments of the present invention, and the present invention is not limited to these contents unless the gist thereof is exceeded.

<Laminated film>
The laminated film in the present invention has at least a resin base layer and a release layer, and the release layer is disposed in contact with the resin base layer. The resin base material layer represents the base material recovered after the separation process, and the release layer is detached (also referred to as peeling) from the resin base material layer by immersing it in a release liquid, and the separation of the resin base material layer is performed. play a role that contributes to

<Detachment layer>
The release layer in the present invention may be any layer that can be removed from the resin base material using a known release solution, and is preferably a layer containing a water-soluble resin, a compound having an acidic group (however, a layer containing a water-soluble resin), or a layer containing a water-soluble resin. ), a metal vapor deposited layer, or an inorganic oxide (metal oxide) vapor deposited layer. From the viewpoint of base material versatility, the release layer is more preferably a layer containing a compound having an acidic group. Further, from the viewpoint of reducing environmental load, a layer containing a water-soluble resin is more preferable as the release layer.

When the release layer is a metal vapor deposition layer or an inorganic oxide (metal oxide) vapor deposition layer, the vapor deposition layer is preferably formed on a resin base material.
When the release layer is a layer containing a water-soluble resin or a layer containing a compound having an acidic group, the release layer is a layer in contact with the resin base layer, so it is preferably a primer layer, an ink layer, and an adhesive layer. At least one layer selected from the group consisting of agent layers. That is, it is preferable that at least one layer selected from the group consisting of a primer layer, an ink layer, and an adhesive layer is a layer containing a water-soluble resin or a compound having an acidic group.
The acidic group-containing compound may be a resin or a low-molecular compound. These water-soluble resins or compounds having acidic groups may be used alone or in combination of two or more.

At least one layer selected from the group consisting of the primer layer, ink layer, and adhesive layer has a resin component (hereinafter also referred to as binder resin) constituting the layer, which is a water-soluble resin or a resin having an acidic group. It may contain a binder resin and a low molecular compound having an acidic group.
Below, cases in which the release layer is a primer layer, an ink layer, and an adhesive layer will be explained.

[Detachable primer layer]
When the release layer is a primer layer, the primer layer is placed in contact with the resin base material and plays the role of releasing the resin base material by dissolving and peeling with a release liquid. The primer layer preferably contains a water-soluble resin or a compound having an acidic group.

(Water-soluble resin)
The water-soluble resin may be any resin that can swell or dissolve in water and be detached from the resin base material. The water may be heated to a temperature of about 25 to 100°C. Thereby, the primer layer can be removed with water (including hot water).
Such resins can be selected from known resins as long as they do not impair water solubility, such as water-soluble polyester resins, water-soluble polyamide resins, water-soluble polyimide resins, water-soluble acrylic resins, water-soluble polyurethane resins, and water-soluble polyurethane resins. Examples include water-soluble polyallylamine resin, water-soluble phenol resin, water-soluble epoxy resin, water-soluble phenoxy resin, water-soluble urea resin, water-soluble melamine resin, polyvinyl alcohol resin, and modified products of these resins. These can be used alone or in combination of two or more. Among them, polyvinyl alcohol (PVA) resin is preferably used from the viewpoint of easy availability and removability.
When the water-soluble resin has film-forming properties, the water-soluble resin may be used as the binder resin constituting the primer layer.

In addition to unmodified polyvinyl alcohol, polyvinyl alcohol resins include modified polyvinyl alcohol obtained by copolymerizing various monomers during the production of vinyl ester resins and saponifying this, and various types of polyvinyl alcohol obtained by post-modification of unmodified polyvinyl alcohol. Various post-modified polyvinyl alcohols into which functional groups have been introduced may also be used. Further, modified polyvinyl alcohol may be further modified after modification. These modifications can be carried out within a range that does not impair the water solubility of the polyvinyl alcohol resin.
These resins may be used alone or in combination of two or more.

Preferred examples of the polyvinyl alcohol resin include resins containing a structural unit having a primary hydroxyl group in the side chain, and ethylene-modified polyvinyl alcohol resins. Among these, polyvinyl alcohol resins containing a structural unit having a primary hydroxyl group in the side chain are preferred because they have excellent water solubility. The number of primary hydroxyl groups in these structural units is usually 1 to 5, preferably 1 to 2, and more preferably 1. Moreover, it is preferable to have a secondary hydroxyl group in addition to the primary hydroxyl group.

The saponification degree (measured according to JIS K 6726) of the polyvinyl alcohol resin used in the present invention is usually 60 to 100 mol%. Further, the preferable range of the degree of saponification varies depending on the modified species; for example, in the case of unmodified polyvinyl alcohol resin, it is usually 60 to 99.9 mol%, preferably 70 to 99.0 mol%, more preferably 75 to 98 mol%. .5%. The degree of saponification of the modified polyvinyl alcohol resin containing a side chain 1,2-diol structural unit is usually 60 to 99.9 mol%, preferably 65 to 99.8 mol%, more preferably 70 to 99.5 mol%. be. If the degree of saponification is too low, water solubility tends to decrease. The degree of saponification of the ethylene-modified polyvinyl alcohol resin modified with a small amount of ethylene is usually 60 mol% or more, preferably 70 to 99.5 mol%, particularly preferably 75 to 99.0 mol%.
It is preferable that the degree of saponification is within the above range because it provides excellent water solubility and good desorption properties. It is also preferable because it has excellent coating properties when forming a primer layer.

The average degree of polymerization of the polyvinyl alcohol resin (measured according to JIS K 6726) is usually 100 to 3,000, preferably 150 to 2,000, more preferably 180 to 1,000, particularly preferably 200 to 800.

(Compound with acidic group)
As the compound having an acidic group, a resin having an acidic group or a low molecular weight compound having an acidic group may be used. Thereby, the primer layer can be removed with the above-mentioned basic aqueous solution.

Examples of the resin having an acidic group include cellulose resin, urethane resin, polyamide resin, vinyl chloride/vinyl acetate copolymer, ketone resin, polyester resin, and (meth)acrylic resin. Examples of the acidic group include a carboxy group, a phosphoric acid group, a sulfo group, a sulfino group, and esters or salts thereof.
Further, as the resin having an acidic group, a rosin modified resin having an acid value such as a maleated rosin or a fumarated rosin can be used.
In addition, as resins having acidic groups, polymerizable monomers having a carboxy group such as itaconic acid, maleic acid, fumaric acid, and cinnamic acid; polymerizable monomers that are acid anhydrides such as itaconic anhydride and maleic anhydride; sulfone Styrene-(meth)acrylic copolymerized with a polymerizable monomer having an acidic group such as a polymerizable monomer having a sulfonic acid group such as styrene; a polymerizable monomer having a sulfonamide group such as vinylbenzenesulfonamide; A radical copolymer such as a resin, a styrene-(anhydrous) maleic acid resin, a terpene-(anhydrous) maleic acid resin, or an acid-modified polyolefin resin can be used.
These may be used alone or in combination of two or more.

The low molecular weight compound having an acidic group refers to a compound having no molecular weight distribution and having a molecular weight of 1,000 or less. Examples of such compounds include saturated fatty acids such as lauric acid, myristic acid, palmitic acid, margaric acid, and stearic acid; oleic acid, linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, sorbic acid, etc. unsaturated fatty acids; hydroxy acids such as lactic acid, malic acid, and citric acid; aromatic carboxylic acids such as benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid, mellitic acid, and cinnamic acid; oxalic acid, Dicarboxylic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, and maleic acid; Tricarboxylic acids such as aconitic acid; Oxocarboxylic acids such as pyruvic acid and oxaloacetic acid; Carboxylic acid derivatives such as amino acids and nitrocarboxylic acids ; Examples include acid anhydrides such as trimellitic anhydride and pyromellitic anhydride.
A low molecular weight compound having an acidic group can form a primer layer by using it in combination with the above-mentioned resin having an acidic group or a known binder resin constituting a known primer layer.

The primer layer preferably contains a compound having an acidic group from the viewpoint of suitability for recoating. Further, from the viewpoint of printability, it is preferable to include a urethane resin having an acidic group, an acrylic resin having an acidic group, and a rosin-modified resin.

[Urethane resin with acidic group]
The urethane resin having an acidic group is not particularly limited, and examples thereof include a urethane resin obtained by reacting a polyol and a polyisocyanate having an acidic group, and a urethane resin obtained by reacting a polyol and a polyisocyanate with an acid-modified hydroxyl group. and resins obtained by acid-modifying the amino groups in a urethane urea resin obtained by reacting a polyamine with an isocyanate group in a urethane resin obtained by reacting a polyol with a polyisocyanate.
Further, as the urethane resin having an acidic group, a resin obtained by reacting a polyol containing a hydroxy acid and a polyisocyanate may be used. By using a hydroxy acid as a polyol, an acid value derived from a carboxy group can be imparted to the urethane resin, and the removability can be improved. Further, when the urethane resin having an acidic group has an isocyanate group, a portion of the isocyanate group may be reacted with a polyamine to introduce a urea bond to form a urethane urea.

《Polyol》
Polyol is a general term for compounds having at least two hydroxyl groups in one molecule. The number average molecular weight of the polyol is preferably 500 to 10,000, more preferably 1,000 to 5,000. The above-mentioned number average molecular weight is calculated from the hydroxyl value of the polyol, and the hydroxyl value refers to a value measured according to JIS K0070. When the number average molecular weight of the polyol is 500 or more, the primer layer has excellent flexibility and improves adhesion to the polyolefin base material. When the number average molecular weight is 10,000 or less, blocking resistance against a polyolefin base material is excellent.

The polyol is not particularly limited, and at least one polyol selected from the group consisting of polyester polyols, polyether polyols, and polycarbonate polyols is more preferably used. Furthermore, the polyol may also contain other dimer diols, hydrogenated dimer diols, castor oil-modified polyols, and the like.
That is, the urethane resin preferably contains a structural unit derived from at least one polyol selected from the group consisting of polyester polyols, polyether polyols, and polycarbonate polyols. More preferably, the polyester polyol contains a structural unit derived from the polyester polyol, since the removability is improved by alkaline hydrolysis of the ester bond site of the polyester polyol.
The content of the structural unit derived from the polyol is preferably 10 to 75% by mass, more preferably 15 to 70% by mass, and even more preferably 20 to 65% by mass, based on the total amount of the urethane resin. The content of the structural units derived from the polyester polyol is preferably 5% by mass or more, more preferably 30% by mass or more, even more preferably 60% by mass or more, particularly preferably 80% by mass, based on the total amount of the polyester polyol-derived structural units. That's all.

《Hydroxy acid》
The polyol may also contain a hydroxy acid. The above-mentioned hydroxy acid refers to a compound having both a hydroxyl group, which is an active hydrogen group, and an acidic functional group in one molecule. The acidic functional group refers to a functional group that can be neutralized with potassium hydroxide when measuring an acid value, and specifically includes a carboxy group and a sulfonic acid group, with a carboxy group being preferred. As such a hydroxy acid, for example, dimethylolalkanoic acids such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, and 2,2-dimethylolvaleric acid are preferably used.

《Polyisocyanate》
The above polyisocyanate is not particularly limited and can be selected from conventionally known polyisocyanates. Preferably, the diisocyanate or triisocyanate is included, and more preferably an aromatic, aliphatic or alicyclic diisocyanate is included. These may be used alone or in combination of two or more.

《Polyamine》
The polyamine used to form the urethane urea is not particularly limited, and is preferably a diamine compound. Further, a diamine having a hydroxyl group may be used since it can introduce a hydroxyl group into the urethane resin.

The acid value of the urethane resin having acidic groups is preferably 15 mgKOH/g or more, more preferably 15 to 70 mgKOH/g, and still more preferably 20 to 50 mgKOH/g. It is preferable that the content is 15 mgKOH/g or more because the releasability with the desorption liquid becomes good, and it is preferable that the content is 70 mgKOH/g or less because the adhesion to the substrate and the retort resistance are good. The hydroxyl value of the urethane resin is preferably 1 to 35 mgKOH/g, more preferably 10 to 30 mgKOH/g. If it is 1 mgKOH/g or more, the releasability by the desorbing liquid will be good, so it is preferable, and if it is 35 mgKOH/g or less, the adhesion to the substrate will be good, so it is preferable.

The weight average molecular weight of the urethane resin having acidic groups is preferably 10,000 to 100,000, more preferably 15,000 to 70,000, even more preferably 15,000 to 50,000. The molecular weight distribution (Mw/Mn) of the urethane resin is preferably 6 or less. Mw represents weight average molecular weight, and Mn represents number average molecular weight. When the molecular weight distribution is 6 or less, the releasability, drying properties of the primer composition, and retort resistance are excellent. Further, the smaller the molecular weight distribution, that is, the sharper the molecular weight distribution, the more uniformly the dissolution and peeling action by the desorbing liquid occurs, and the releasability of the resin base material improves. The molecular weight distribution is more preferably 5 or less, still more preferably 4 or less. Further, the molecular weight distribution is preferably 1.5 or more, more preferably 1.2 or more.
In this specification, Mw, Mn, and molecular weight distribution (Mw/Mn) are polystyrene equivalent values determined by gel permeation chromatography (GPC).

The urethane resin having an acidic group may have an amine value. When the urethane resin has an amine value, the amine value is preferably 0.1 to 20 mgKOH/g, more preferably 1 to 10 mgKOH/g. Within the above range, the adhesion to the substrate is excellent.

The number of urethane bonds in the polyurethane resin having acidic groups is preferably 1 to 3 mmol/g, more preferably 1.5 to 2 mmol/g. Further, the number of urea bonds is preferably 0 to 3 mmol/g, more preferably 0.2 to 1 mmol/g. Further, the total number of urethane bonds and the number of urea bonds is preferably 1 to 6 mmol/g, more preferably 1.7 to 3 mmol/g.
By setting the number of urethane bonds and the number of urea bonds within the appropriate ranges, the releasability and substrate adhesion are improved.

[Acrylic resin with acidic group]
Examples of acrylic resins having acidic groups include polymers obtained by polymerizing monomers containing (meth)acrylic monomers having acidic groups such as (meth)acrylic acid and maleic acid; (meth)acrylic monomers having hydroxyl groups and glycidyl groups; After polymerizing a monomer containing a monomer, the functional group is modified to introduce a carboxy group (for example, a maleic anhydride-modified resin).
The acid value of the acrylic resin having an acidic group is preferably 50 mgKOH/g or more, more preferably 100 mgKOH/g or more.

[Rosin modified resin]
Rosin modified resin is a resin prepared using rosin as one of the raw materials. Rosin contains a mixture of resin acids such as abietic acid, palustric acid, isopimaric acid, and levopimaric acid, and these resin acids contain hydrophilic and chemically active carboxy groups, and some contain conjugated double bonds. There are things to prepare for. Therefore, polyhydric alcohols and polybasic acids are combined to perform condensation polymerization, resol, which is a condensate of phenol, is added to the benzene ring contained in the rosin skeleton, and dienophilic maleic anhydride or maleic acid is reacted with Diels-Alder reaction. Various rosin-modified resins have been prepared by adding a maleic acid or maleic anhydride skeleton to the rosin. Various kinds of such rosin modified resins are commercially available, and it is also possible to obtain and use them.

Examples of the rosin-modified resin include maleated rosin, fumarized rosin, rosin-modified maleic acid resin, rosin-modified fumaric acid resin, rosin-modified phenol resin, rosin-modified alkyd resin, and rosin-modified polyester resin. In the present invention, any rosin-modified resin may be used, but among these, at least one selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, and fumaric anhydride is derived from the structure thereof. It is preferable to use a compound containing a portion as follows. A resin that “contains in its structure at least one moiety selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, and fumaric anhydride” refers to a resin that contains maleic acid, maleic anhydride, It is prepared using at least one selected from the group consisting of acid, fumaric acid, and fumaric anhydride, such as rosin-modified maleic acid obtained by condensation polymerization of maleic acid or fumaric acid as part of a polybasic acid. Acid resins, rosin-modified fumaric acid resins, maleated rosins and fumarated rosins with structures in which maleic acid, maleic anhydride, fumaric acid, and fumaric anhydride are added as dienophiles through Diels-Alder reactions, and the functionalities contained in these. It means a resin etc. in which other chemical species are polymerized using the group.

The acid value of the rosin modified resin is preferably 10 to 400 mgKOH/g, more preferably 100 to 300 mgKOH/g.

(Other ingredients)
The primer layer may contain a resin other than a water-soluble resin or a compound having an acidic group.
Examples of such resins include cellulose resins, polyamide resins, vinyl chloride resins such as vinyl chloride-vinyl acetate copolymer resins and vinyl chloride-acrylic copolymer resins, ethylene-vinyl acetate copolymer resins, and vinyl acetate resins. , acrylic resin, styrene resin, dammar resin, styrene-acrylic copolymer resin, polyester resin, alkyd resin, terpene resin, phenol-modified terpene resin, ketone resin, cyclized rubber, chloride rubber, butyral, polyacetal resin, petroleum resin, and These modified resins can be mentioned. These resins may be used alone or in combination of two or more.
Among these, the primer layer preferably contains at least one resin selected from the group consisting of cellulose resin, vinyl chloride resin, rosin resin, and acrylic resin. More preferably, vinyl chloride resin or acrylic resin is included.
The mass ratio of the urethane resin having acidic groups to other resins (urethane resin having acidic groups: other resins) is preferably 95:5 to 50:50. If it is within the above range, when the ink layer is peeled off together with the primer layer in a basic aqueous solution, the ink layer will be peeled off in a thin film state, making it easy to recover.

The primer layer may contain an extender pigment. Examples of extender pigments include metal oxides such as silica, barium sulfate, kaolin, clay, calcium carbonate, magnesium carbonate, zinc oxide, and zirconium oxide. Among these, silica is preferred, and hydrophilic silica is more preferred.
The average particle diameter of the extender pigment is preferably 0.5 to 10 μm, more preferably 1 to 8 μm. The content of the extender pigment in the primer layer is preferably 0.5 to 10% by mass, more preferably 1 to 5% by mass. When the average particle diameter and the content of the extender pigment are within the above ranges, the wettability of the ink layer is improved and the image quality is improved.

The primer layer may be a layer in which the above-mentioned urethane resin having acidic groups is crosslinked with a curing agent. By introducing a crosslinked structure into the primer layer, penetration and bleeding of the ink layer formed on the primer layer are suppressed, and excellent image quality can be exhibited.
Examples of the curing agent include polyisocyanate. The polyisocyanate is not particularly limited and can be selected from conventionally known polyisocyanates, such as aliphatic polyisocyanates and araliphatic polyisocyanates. These may be used alone or in combination of two or more.

The primer layer may further contain known additives. Known additives include, for example, dispersants, wetting agents, adhesion aids, leveling agents, antifoaming agents, antistatic agents, viscosity modifiers, metal chelates, trapping agents, antiblocking agents, wax components other than those listed above, Examples include silane coupling agents.

The thickness of the primer layer is preferably in the range of 0.5 to 3.0 μm, more preferably 0.6 to 2.0 μm, even more preferably 0.8 to 1.5 μm, and is formed using a known method. be able to.

[Removable ink layer]
The ink layer is a layer that forms an arbitrary printed pattern for the purpose of decoration, imparting beauty, displaying contents, expiration date, manufacturer or seller, etc., and includes a solid printing layer.
When the release layer is an ink layer, the ink layer is placed in contact with the resin base material and plays the role of releasing the resin base material by dissolving and peeling with a release liquid. The ink layer preferably contains a water-soluble resin or a compound having an acidic group, and a colorant. Further, the method of forming the ink layer is not limited, and it can be formed using a known method.
From the viewpoint of recoating suitability, the ink layer preferably contains a compound containing an acidic group. Further, from the viewpoint of printability, it is preferable to include a urethane resin having an acidic group, an acrylic resin having an acidic group, and a rosin-modified resin.
The water-soluble resin and the compound having an acidic group, the urethane resin having an acidic group, the acrylic resin having an acidic group, and the rosin-modified resin are the (water-soluble resin) and ( The descriptions of compounds having acidic groups), urethane resins having acidic groups, acrylic resins having acidic groups, and rosin-modified resins can be cited.

(colorant)
The ink layer may be colored or colorless and contains known colorants used in printing inks and paints. Such coloring agents are not particularly limited, and in addition to inorganic pigments, organic pigments, and dyes, metal powders that provide metallic luster, near-infrared absorbing materials, and ultraviolet absorbing materials may be used.
Examples of inorganic pigments include colored pigments such as titanium oxide, red iron oxide, navy blue, ultramarine blue, carbon black, and graphite; extender pigments such as calcium carbonate, kaolin, clay, barium sulfate, aluminum hydroxide, and talc.
As the organic pigment, soluble azo pigments, insoluble azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, condensed polycyclic pigments, etc. are preferably used.
Note that the pigments are not limited to these, and those described by the generic names of Color Index can be used as appropriate. Among these, when the desorbing liquid is a basic aqueous solution, a pigment that does not dissolve in the basic aqueous solution and has alkali resistance is preferable. By preventing pigment elution, the base aqueous solution can be easily reused.
The alkali resistance of a pigment is generally estimated based on the skeleton or structure of the pigment, and examples of pigments with alkali resistance include inorganic pigments, C.I. I. Pigment Blue 15, C. I. Pigment Yellow 83 is mentioned.
When the pigment is titanium oxide, the content of titanium oxide in the ink layer is preferably 20 to 80% by mass, more preferably 30 to 75% by mass. Further, when the pigment is an inorganic pigment other than titanium oxide, an extender pigment, or an organic pigment, the content of each of these pigments in the ink layer is preferably 0.5 to 60% by mass, more preferably 10 to 50% by mass. Mass%.

(Other ingredients)
The ink layer may contain a pigment derivative or a resin-type dispersant as a colorant dispersant.
The pigment derivative is a compound having a substituent introduced into the skeleton of the pigment, and the content of the pigment derivative is preferably 0.01 to 10% by mass, more preferably 0.05 to 6% by mass, based on the mass of the colorant. The amount is % by mass, more preferably 0.1 to 4% by mass. When it is 0.01% by mass or more, the resin base material has excellent detachability, and when it is 10% by mass or less, redeposition of the ink layer can be suppressed.
The resin-type dispersant acts to stabilize the dispersion in printing ink etc. by adsorbing on the colorant, and can be appropriately selected from known resin-type dispersants. The content of the resin type dispersant is preferably 0.01 to 30% by mass, more preferably 0.05 to 20% by mass, and even more preferably 0.1 to 10% by mass, based on the mass of the colorant. . When it is 0.01% by mass or more, the resin base material has excellent releasability, and when it is 30% by mass or less, the ink layer has excellent water resistance.

The ink layer may contain a resin other than a water-soluble resin or a compound containing an acidic group.
Such resins include, for example, nitrocellulose, fiber materials such as cellulose acetate/propionate, chlorinated polypropylene, vinyl chloride-vinyl acetate copolymer, polyester, acrylic, urethane resin, and acrylic urethane. Examples include polyamide-based, polybutyral-based, cyclized rubber-based, and chlorinated rubber-based resins. These resins may be used alone or in combination of two or more.

The thickness of the ink layer is preferably 0.1 μm or more and 100 μm or less, more preferably 0.1 μm or more and 10 μm or less, and still more preferably 1 μm or more and 5 μm or less.

[Removable adhesive layer]
When the release layer is an adhesive layer, the adhesive layer is placed in contact with the resin base material and plays the role of releasing the resin base material by dissolving and peeling with a release liquid. The adhesive layer preferably contains a compound having an acidic group. When the adhesive layer contains a resin having an acidic group or a low molecular weight compound having an acidic group, the adhesive layer can be removed using the above-mentioned basic aqueous solution.
For the above-mentioned compound having an acidic group, resin having an acidic group, and low molecular weight compound having an acidic group, the description of (compound having an acidic group) in the above-mentioned [Detachable Primer Layer] section can be referred to.
Further, the method of forming the adhesive layer is not limited, and it can be formed using a known method.

From the viewpoint of removability, the adhesive layer is a cured adhesive containing a polyester polyol having an acidic group and at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates and araliphatic polyisocyanates. It may be. The cured product corresponds to a resin having an acidic group.
Further, the adhesive layer is a cured product of an adhesive containing a polyester polyol, at least one polyisocyanate selected from the group consisting of aliphatic polyisocyanates and araliphatic polyisocyanates, and a low molecular compound having an acidic group. It may be.

(Polyester polyol)
The polyester polyol only needs to have an acidic group, and can be appropriately selected from known polyester polyols. By including such a polyester polyol, when a basic aqueous solution is used as a desorption liquid, it is preferable because the desorption property is improved by having an ester bond that has a high affinity with a basic compound. One type of polyester polyol may be used alone, or two or more types may be used in combination.

Polyester polyols include, but are not particularly limited to, polyester polyols obtained by reacting carboxy group components (also referred to as polycarboxylic acids) and hydroxyl group components (also referred to as polyhydric alcohols); polycaprolactone, polyvalerolactone, poly(β Polyester polyols obtained by ring-opening polymerization of lactones such as -methyl-γ-valerolactone) are preferably used.
Examples of the carboxy group components include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic anhydride, adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and anhydrous Examples include dibasic acids such as maleic acid and itaconic anhydride, dialkyl esters thereof, and mixtures thereof.
Examples of the hydroxyl group component include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, butylene glycol, neopentyl glycol, trimethylolpropane, glycerin, 1,6-hexanediol, 1,4-butanediol , 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptane, 1,9-nonanediol, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether Examples include diols such as glycol, polyether polyol, polycarbonate polyol, polyolefin polyol, acrylic polyol, and polyurethane polyol, or mixtures thereof.
Two or more of the above carboxy group components and hydroxyl group components may be used in combination.

The polyester polyol may be a polyester urethane polyol obtained by reacting a polyisocyanate with a hydroxyl group in a polyol. Because polyester polyol has urethane bonds, it exhibits excellent heat resistance and adhesive properties.
Examples of the polyisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 1,5-naphthalene diisocyanate, hexamethylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. can be mentioned.

Further, the polyester polyol may be an acid anhydride-modified product obtained by reacting an acid anhydride with a hydroxyl group in the polyol. Thereby, a carboxy group, which is an acidic group, can be introduced into the polyester polyol.
Examples of the acid anhydride include pyromellitic anhydride, mellitic anhydride, trimellitic anhydride, and trimellitic acid ester anhydride. Examples of the trimellitic acid ester anhydride include ethylene glycol bisanhydrotrimellitate and propylene glycol bisanhydrotrimellitate.

The acid value of the polyester polyol is preferably 5.0 mgKOH/g or more, more preferably 10.0 mgKOH/g or more. Further, the acid value of the polyester polyol is preferably 100 mgKOH/g or less, more preferably 80 mgKOH/g or less. When the acid value of the polyester polyol is within the above range, when the polyester polyol is brought into contact with a desorption liquid that is a basic aqueous solution, the basic aqueous solution penetrates and is decomposed, thereby exhibiting better desorption properties.
When the adhesive contains a plurality of polyester polyols, the acid value of the entire polyester polyol can be determined from the acid value of each polyester polyol and its mass ratio.

The number average molecular weight (Mn) of the polyester polyol is preferably 3,000 to 25,000, more preferably 5,000 to 20,000, particularly preferably 7,000 to 15,000. When the number average molecular weight of the polyester polyol is 3,000 or more, it can exhibit not only coating properties but also sufficient retort suitability, and when it is 20,000 or less, not only coating properties but also removability are improved. It is preferable to do so.

The polyester polyol component may contain a plurality of polyester polyol components in combination, for example, a polyester polyol having a number average molecular weight of 5,000 to 20,000, in order to satisfy various physical properties required for packaging materials. Furthermore, in order to improve the adhesion to the base material, a polyester polyol having a number average molecular weight of less than 3,000 may be included.
The content of the polyester polyol having a number average molecular weight of less than 3,000 is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, based on the total mass of the polyester polyol. When the content is 30% by mass or less, retort resistance can be maintained.

(Other polyols)
The adhesive constituting the adhesive layer may contain polyols other than polyester polyol. Polyols that may be contained other than polyester polyols are not particularly limited, and examples include polycarbonate polyols, polycaprolactone polyols, polyether polyols, polyolefin polyols, acrylic polyols, silicone polyols, castor oil polyols, and fluorine polyols. .

(Polyisocyanate)
The polyisocyanate to be combined with the above-mentioned polyester polyol to form the adhesive layer is preferably at least one selected from the group consisting of known aliphatic polyisocyanates and araliphatic polyisocyanates.

Examples of the aliphatic polyisocyanate include acyclic aliphatic diisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, and 1,2-butylene diisocyanate; 1,4-cyclohexane diisocyanate; Alicyclic diisocyanates such as 1,3-cyclohexane diisocyanate and 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (hereinafter referred to as isophorone diisocyanate); allophanate type, nurate type, biuret type derived from the above diisocyanates , adduct-type derivatives, or complexes thereof.
The derivative is preferably a nurate type or an adduct type, and more preferably an adduct type. As the aliphatic polyisocyanate, a polyisocyanate derived from hexamethylene diisocyanate (hereinafter also referred to as HDI) is preferred because it can easily ensure a balance between removability and laminate physical properties.

Examples of the araliphatic polyisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω,ω'-diisocyanate-1,4-diethylbenzene, 1,3- or 1,4-bis( Aroaliphatic diisocyanates such as 1-isocyanate-1-methylethyl)benzene or mixtures thereof; derivatives of allophanate type, nurate type, biuret type, adduct type, or complexes thereof derived from the above araliphatic diisocyanates; Examples include polyisocyanate.

(Other polyisocyanates)
The adhesive may contain polyisocyanates other than aliphatic polyisocyanates and araliphatic polyisocyanates, as long as the effects of the present invention are not impaired. Examples of such polyisocyanates include aromatic diisocyanates such as toluene diisocyanate and diphenylmethane diisocyanate; polyisocyanates such as derivatives of the above diisocyanates, or complexes thereof.

The blending ratio of the polyol and polyisocyanate may be such that the molar ratio of isocyanate groups in the polyisocyanate to hydroxyl groups in the polyol (NCO/OH) is 0.3 to 10.0. It is preferably 0.3 to 7.0, more preferably 0.5 to 5.0.

(Other ingredients)
The adhesive layer contains a silane coupling agent, a phosphorus oxygen acid or its derivative, a leveling agent, an antifoaming agent, a reaction accelerator, and an inorganic filler (for example, silica, alumina, mica, talc, aluminum flakes, glass flakes). ), layered inorganic compounds, stabilizers (e.g. antioxidants, heat stabilizers, ultraviolet absorbers, hydrolysis inhibitors), rust inhibitors, thickeners, plasticizers, antistatic agents, lubricants, antiblocking agents, It may contain a colorant, a filler, a crystal nucleating agent, a catalyst for adjusting the curing reaction, and the like.

The thickness of the adhesive layer is preferably in the range of 1 to 10 μm, more preferably in the range of 1 to 6 μm.

[Metal deposition layer, inorganic oxide deposition layer]
A metal vapor deposited layer such as aluminum and an inorganic oxide vapor deposit layer such as alumina or silica dissolve in a basic aqueous solution and are released, so they function as a release layer and can separate adjacent resin base materials. .
The thickness of the metal deposited layer and the inorganic oxide deposited layer is not particularly limited, but is preferably 0.001 to 5 μm.

<Resin base layer>
The resin base material constituting the resin base layer is not particularly limited, but is preferably a sheet-shaped resin base material, such as a conventionally known plastic film. The resin base material layer may have a single layer structure consisting of one resin base material, or may have a multilayer structure consisting of a plurality of resin base materials. Further, when the resin base material layer has a structure in which two resin base materials are laminated via an adhesive layer, the two resin base materials may be of the same type or different types. good.

As the plastic film, a thermoplastic resin or thermosetting resin film can be used, and preferably a thermoplastic resin film. Examples of the thermoplastic resin include polyolefin resin, polyester resin, polyamide resin, polystyrene resin, vinyl chloride resin, vinyl acetate resin, ABS resin, acrylic resin, acetal resin, polycarbonate resin, and cellulose plastic.
The resin base material may be provided with a vapor deposited layer (barrier layer) as described in the above-mentioned [Metal vapor deposited layer] or [Inorganic oxide vapor deposited layer] section as a release layer.

Specific examples of plastic films include, for example, polyester resin films such as polyethylene terephthalate, polyethylene naphthalate (PEN), and polylactic acid (PLA); polyolefin resin films such as polyethylene (PE) and polypropylene (PP); polystyrene resin films; Polyamide resin films such as nylon 6 and poly-p-xylylene adipamide (MXD6 nylon); polycarbonate resin films; polyacrylonitrile resin films; polyimide resin films; composites of these (for example, nylon 6/MXD6/nylon) 6, nylon 6/ethylene-vinyl alcohol copolymer/nylon 6) and mixtures. Among these, those having mechanical strength and dimensional stability are preferred.
The thickness of the plastic film is not particularly limited, but is preferably 5 to 100 μm, more preferably 10 to 50 μm.

Moreover, a sealant base material can be used as the plastic film.
Examples of the sealant base material include polyethylene such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE), acid-modified polyethylene, polypropylene (PP), acid-modified polypropylene, and copolymer. Examples include polypropylene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid ester copolymer, ethylene-(meth)acrylic acid copolymer, and ionomer.
The thickness of the sealant base material is not particularly limited, but in consideration of processability into packaging materials, heat sealability, etc., it is preferably 10 to 200 μm, more preferably 15 to 150 μm. Further, by providing the sealant base material with unevenness having a height difference of about several micrometers, slipperiness and tearability of the packaging material can be imparted.

It is important that the resin base material constituting the resin base layer does not soften during shredding and block the cross section of the release layer. Therefore, the melting point of the resin base material is preferably 90°C or higher, more preferably 100°C or higher, and even more preferably 120°C or higher.

<Structure of laminated film>
The laminated film in the present invention only needs to have at least a resin base layer and a release layer, and may further have another layer as long as the effects of the present invention are not impaired. Examples of layers that may include resin-containing layers that do not fall under the release layer (e.g., ink layer, adhesive layer, primer layer, overcoat layer), metal foil such as aluminum foil, natural Examples include papers such as paper and synthetic paper.

Examples of the laminated film include the following configurations, and may have a configuration that satisfies two or more of the following configurations.
(1) It has a partial structure including a resin base material layer and an ink layer in this order, and the ink layer is a release layer.
(2) It has a partial structure including a resin base material layer, a primer layer, and an ink layer in this order, and the primer layer is a release layer.
(3) It has a partial structure in which two resin base material layers are laminated with an adhesive layer interposed therebetween, and the adhesive layer is a release layer.
A specific example of the above configuration is shown below.
Resin base material layer/release ink layer,
Resin base material layer/release primer layer/ink layer,
Resin base layer/release ink layer/release adhesive layer/resin base layer,
Resin base layer/release primer layer/ink layer/release adhesive layer/resin base layer,
Resin base layer/ink layer/release adhesive layer/resin base layer,
Resin base material layer/removable adhesive layer/resin base material layer,
Ink layer/resin base layer/release adhesive layer/resin base layer,
Ink layer/resin base layer/adhesive layer/resin base layer/release adhesive layer/resin base layer,
release ink layer/resin base layer/release adhesive layer/resin base layer,
Ink layer / release primer layer / resin base layer / release adhesive layer / resin base layer,
Resin base material layer / release primer layer / ink layer / release adhesive layer / inorganic oxide vapor deposited layer (release layer) / resin base material layer,
Resin base layer/release primer layer/ink layer/adhesive layer/inorganic oxide vapor deposited layer (release layer)/resin base layer/release adhesive layer/resin base layer.

<Separation and recovery method of laminated film>
The separation and recovery method of the present invention includes the following steps.
(1) A shredding step in which the laminated film is shredded while being cooled with water whose temperature has been lowered to 50°C using a cooling means to obtain shredded products. (2) A shredding step in which the shredded material is immersed in a desorption liquid. , separation step of separating the resin base layer (3) recovery step of recovering the separated resin base layer

[Step (1)] Shredding step Step (1) is a step of shredding the laminated film to obtain shredded products. It is important to shred. By shredding while cooling with water at 50°C or less, the resin base material is prevented from melting due to the heat generated when shredding a large amount with a shredding device and blocking the cross section of the release layer. I can do it. As a result, the exposure of the cross section of the release layer is not prevented, and the releasability is not reduced.
Furthermore, by using a cooling means, the temperature of the water can be kept at 50° C. or lower at all times, so that it is possible to prevent the cross section of the detachment layer from being blocked during the entire shredding process. If a cooling means is not used, the liquid temperature will rise due to the heat generated during shredding, making it difficult to exert a cooling effect.
The lower the temperature of the water, the better from the viewpoint of preventing softening and fusion during shredding, and is preferably 39°C or lower, more preferably 29°C or lower, and still more preferably 20°C or lower. If it is within the above range, temperature rise due to shearing during shredding is suppressed, the resin base material of the laminated film is difficult to melt and soften, and the cross section of the release layer is easily exposed, which is preferable.

There are no particular restrictions on the cooling means for reducing the temperature of the water to 50°C or lower. For example, there may be a method of constantly introducing new water of 50°C or lower into the shredding section, a method of recycling water, or a method of using warmed water. Examples include, but are not limited to, a method in which the liquid is cooled to 50°C or less using a cooling device and then thrown into the shredding section at any time, and a method in which a cooling device is installed in the shredding device to maintain the liquid temperature at 50°C or less. . The method of the cooling device is not limited, and can be appropriately selected from known methods such as an air cooling method and a liquid cooling method.

Examples of the shredding method include a method using a cutter mill (rotary cutter), and examples of shredding devices using a cutter mill include Tanaka's MF45-700WRS and Nippon Seam's PF-2000 model. .

An example of the shredding process in the present invention is shown below.
Water at a temperature of 50°C or less is continuously introduced from the water inlet of the shredding device. The continuous cooling means enables cooling and shredding with water at a liquid temperature of 50° C. or lower. The water injected from the water inlet may be injected using a spray nozzle or the like in order to efficiently wet and cool the shredded material in the apparatus.
On the other hand, the laminated film is input from the laminated film input port, and is shredded to a predetermined size or less in the shredding section together with water supplied from the water inlet. A known structure can be used for the shredded portion. In the shredding section, it is preferable to use a rotary cutter that shreds using shearing force.

In the shredding process, a detergent or the like may be added to the water in order to wash away dirt such as contents adhering to the laminated film. Further, the water used in the shredding step may contain components of a desorption liquid. When the water used in the shredding process contains components of a cleaning agent and a desorption liquid, separation in the separation process can be promoted.
However, the present invention is characterized in that the shredding step and the separation step are performed separately from the viewpoint of preventing impurities such as ink pieces from adhering to and accumulating on the resin base material. The components of the cleaning agent and desorption liquid that may be contained in the water used for this process must be within a range that does not cause separation of the resin base layer.

As the shredding progresses and the size of the shredded material falls below a certain level, it passes through a screen installed at the bottom of the shredder due to its own weight along with water. A screen refers to something that has the role of a filter that allows things smaller than a certain size to pass through, and is sometimes called a filter or a grid. The shape of the screen may be circular, diamond-shaped, fan-shaped, etc., and can be appropriately selected depending on the hardness and thickness of the shredded material.
The long side of the shredded material can be adjusted depending on the size of the screen used. For example, if the screen shape is circular, by using a screen with a diameter of 15 mm, the length of the longest side of the shredded material can be adjusted. The length (long side) can be controlled to 15 mm.
The long side of the shredded material is preferably 5 to 50 mm, more preferably 5 to 40 mm, and still more preferably 10 to 30 mm. Within the above range, in step (2) described later, the time for the desorbed liquid to permeate from the end face to the center of the shredded material is shortened, and separation and recovery can be performed efficiently.

The mass of water used in the shredding step is preferably 2 to 500 times, more preferably 10 to 250 times, even more preferably 15 to 150 times the mass of the laminated film.
Within the above range, the amount of water for cooling the laminated film will be sufficient, and water will constantly flow in and out of the shredded parts, suppressing local temperature rises in the shredded parts due to shearing. Ru. Thereby, fusion and softening of the resin base material of the laminated film can be suppressed.
In addition, by keeping the amount of water within the above range, not only the shredded material but also unnecessary components such as minute ink pieces and adhesive pieces generated during shredding can easily pass through the screen mentioned above, making it easier to cut into pieces. It is possible to prevent the accumulation of laminated films in the parts and clogging of the screen due to unnecessary components.
This prevents the laminated film from excessively staying in the shredded portion, and can suppress the fusion of the resin base material and the generation of fine pieces due to excessive shredding. Furthermore, by suppressing screen clogging, it is possible to continuously produce shredded products of a constant size.
The mass of water used in the shredding process refers to the mass of water that is input into the shredding device per minute, and the mass of the laminated film refers to the mass of the laminated film that is input into the shredder per minute. represents.

Since the separation and recovery method of the present invention performs the shredding step as an efficient liquid, it includes a sorting step of sorting out the laminated film of the present invention having at least a resin base layer and a release layer before the shredding step. You can leave it there.
Further, before the shredding step, a rough shredding step may be included in which the laminated film is shredded to a size that can be easily fed into a shredding device. Examples of the device used in the rough crushing step include a hydraulic cutter.

[Step (4)] Washing and Filtration Step The separation and recovery method of the present invention may include the following step (4) between step (1) and step (2) described below.
(4) Washing and filtration process in which the shredded material is washed with water to remove fine particles. When recycling the resin base material, it is preferable to wash the shredded material with water and perform washing and filtration to remove fine pieces, since unnecessary components that degrade the quality are mixed therein. The cleaning and filtration process removes most of the adhered food residue, fine particles (ink pieces, adhesive pieces, etc.) and other contaminants.
In the series of steps from shredding to drying and transporting, it is preferable to use a continuous processing method because the work efficiency is improved if the processing is performed while water and the laminated film are continuously supplied from the water-cooled shredding device.

In the washing and filtration process, known methods such as washing with water by showering can be used for washing. For filtration, known methods for removing impurities along with the filtrate, such as a filter press, a filter screen, and a centrifugal dehydrator, can be used. In the filtration step, it is preferable to use a filtration screen from the viewpoint of collecting shredded material of a certain size or more and removing other fine pieces.
A filtration screen is sometimes referred to as a filter or a grid. The shape of the screen includes, for example, a circular shape, a diamond shape, and a fan shape, and can be appropriately selected depending on the shape of the object to be filtered. By washing the shredded material with water and using a filtration screen to leave the shredded material behind and remove the fine particles, it is possible to separate and collect higher quality films.
Among these, a centrifugal cleaning/filtration mechanism in which the material is washed and filtered by centrifugal force and sent to the outlet is suitable for step (4). A centrifugal cleaning filter mainly has a cylindrical filter screen fixed to the inner surface of a cylindrical outer cylinder in a double cylindrical shape. A rotating rotor having a rotating shaft coaxial with the central axis of the cleaning filtration device is provided inside the filtration screen. Further, a scraper blade is attached to the rotating rotor, and the shredded material is transported to the outlet while rotating. With these mechanisms, the water containing shredded material and fine particles that has passed through step (1) above is sent inside the washing filtration device to the outlet, where only the shredded material larger than the size of the filter screen is sent to the outlet, and the water and fine particles are Fine particles are continuously discharged out of the filter screen.
It is preferable that the shape and size of the filtration screen be adjusted so that as much of the shredded material to be collected as possible remains within the screen, and fine particles, which are unnecessary components, are discharged outside the screen. When the shape of the screen is circular, its diameter is preferably 0.1 mm to 45 mm, more preferably 0.5 mm to 30 mm, and still more preferably 0.5 mm to 15 mm. Water and fines discharged outside the filtration screen are discharged through drains.
Although the shape of the fine pieces is not particularly limited, the length or diameter thereof is preferably 10 mm or less.

The shape of the washing filtration device may be either vertical or horizontal, and is appropriately selected depending on the size of the device and ease of connection with other devices.
The water used in step (1) and step (4) above may be reused after undergoing an impurity removal process.

The shredding and washing/filtering device is not particularly limited, but, for example, those manufactured by Tanaka and Nippon Seam can be used.

[Step (2)] Separation Step Step (2) is a step of immersing the obtained shredded material in a desorption liquid to separate the resin base material layer, and can be appropriately selected from known methods.

(Desorption liquid)
The release liquid may be one that causes the resin base material to peel off by swelling and dissolving the release layer, and can be appropriately selected in consideration of the ease with which the release layer can be removed. Examples of such a desorption liquid include water, a basic aqueous solution, an acidic aqueous solution, and a fluorinated solvent. From the viewpoint of the environment and maintaining the properties of recycled materials using recovered resin base materials, water or an aqueous solution is preferable. Moreover, since it is possible to remove both the layer containing the compound having an acidic group and the layer containing the water-soluble resin, a basic aqueous solution containing a basic compound is more preferable. These desorption liquids may be heated.

[Basic compound]
The basic compound is not particularly limited, and examples include sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH) ₂ ), ammonia, barium hydroxide (Ba(OH) ₂ ), and carbonic acid. Sodium (Na ₂ CO ₃ ) is preferably used. More preferably, it is at least one selected from the group consisting of sodium hydroxide and potassium hydroxide.
The content of the basic compound in the basic aqueous solution is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, even more preferably 3 to 15% by mass, based on the mass of the basic aqueous solution. range. Within the above range, the basic aqueous solution can maintain sufficient basicity to remove the release layer by dissolving or swelling and recovering the resin base layer.

As described above, the desorption liquid permeates through the end face of the shredded material, contacts the desorption layer, and dissolves or swells, thereby separating the resin base layer and the desorption layer. Since the shredded material obtained in step (1) is shredded while being cooled with water whose liquid temperature is lower than 50°C using a cooling means, fusion and softening of the resin base layer is suppressed. The cross section of the detachment layer is exposed. Therefore, the desorption liquid permeates into the desorption layer in a shorter time, and the resin base material layer can be efficiently desorbed.

The temperature of the desorption liquid when immersing the shredded material is preferably in the range of 25 to 120°C, more preferably 30 to 120°C, particularly preferably 30 to 80°C. The immersion time in the desorption solution is preferably in the range of 1 minute to 24 hours, more preferably 1 minute to 12 hours, and preferably 1 minute to 6 hours. The amount of desorption liquid to be used is preferably 50,000 to 100,000 times, more preferably 100,000 to 100,000 times the mass of the shredded material. It is preferable to stir or circulate the liquid. The rotation speed is preferably 80 to 5000 rpm, more preferably 80 to 4000 rpm.

As the desorption liquid, the water used in step (1) or step (4) may be reused after removing impurities.

[Step (3)] Recovery Step Step (3) is a step of recovering the resin base material layer separated in Step (2), and can be appropriately selected from known recovery methods. Examples of the above-mentioned recovery method include a method using filter filtration. The method includes filters such as cartridge filters, belt filters, drum filters, dynafilters, rotary filters, meshes, screens, drum screens, slurry screeners, autostrainers, pusher centrifuges, continuous centrifuges, and filtration systems. It includes any separation means including a filter, and a mesh conveyor that can convey the material while filtering with the filter may be used.

In the step (3), before recovering the resin base layer, a step of removing components other than the resin base layer, such as ink and adhesive separated from the laminated film, may be provided. The components such as the ink and adhesive mentioned above are finely divided by the shearing force in step (2), so the size of the filter is adjusted using the difference in size from the shredded material shredded in step (1). By doing so, the resin base material layer can be recovered while removing fine pieces of ink and adhesive components adhering to the resin base material component.
The desorption liquid after collecting the resin base layer and removing components other than the resin base layer, such as ink and adhesive, may be reused in step (2).

Step (3) may include a step of selecting the resin type of the resin base layer (selection step). Examples of the sorting process include a gravity sorting method using a liquid, a wind sorting method, and a near-infrared sorting method.From the viewpoint of productivity, the gravity sorting method using a liquid is preferable.
In the specific gravity sorting method using a liquid, for example, when water is used as the specific gravity liquid, resin base materials with a specific gravity lighter than water such as polyethylene and polypropylene, and resin base materials with a specific gravity higher than water such as polyester, nylon, and cellophane, are separated. can be sorted. The specific gravity liquid may be formulated with an organic solvent, an aqueous solution of a metal salt compound, etc. alone or in combination, and the specific gravity may be adjusted as appropriate. Such specific gravity selection can also be performed multiple times.
The recovered resin base material layer is reused after being subjected to treatments such as dehydration treatment and drying treatment as necessary.

<Reuse of resin base material layer>
The resin base material layer recovered by the separation and recovery method described above can be melt-kneaded to produce a molding material.
In the melting and kneading process, various additives are added as necessary, and the mixture is mixed using a Henschel mixer, tumbler, disper, etc., followed by a kneader, roll mill, super mixer, Henschel mixer, Shugi mixer, vertical granulator, high speed mixer, etc. Mixing and dispersion using fur matrix, ball mill, steel mill, sand mill, vibration mill, attritor, batch kneader such as Banbury mixer, twin screw extruder, single screw extruder, rotor type twin screw kneader, etc. refers to doing. As a result, recycled resin, which is a resin composition, is obtained. The shape of the recycled resin is not particularly limited, and may be in the form of pellets, powder, granules, or beads. It is preferable to use a twin-screw extruder in the melt-kneading step.

The molding material may further contain a masterbatch. The masterbatch is not particularly limited as long as it is compatible with the recycled resin, and generally, a mixture of a thermoplastic resin such as polyethylene resin or polypropylene resin and a colorant can be used. The thermoplastic resins contained in the masterbatch may be used alone or in combination of two or more.
The masterbatch may contain alkali metal, alkaline earth metal, or zinc metal soap, hydrotalcite, nonionic surfactant, cationic surfactant, anionic surfactant, amphoteric surfactant, as long as it does not impede the effects of the present invention. It may contain surfactants, antistatic agents, flame retardants such as halogen-based, phosphorus-based or metal oxides, lubricants such as ethylene bisalkylamides, antioxidants, ultraviolet absorbers, and fillers.

A molded body can be obtained by heat-molding the molding material obtained as described above. The heat molding method is not particularly limited, and examples thereof include injection molding, extrusion molding, blow molding, and compression molding.
The molding material produced using the resin base layer recovered by the separation and recovery method of the present invention has excellent removability because the cross section of the shredded material is not blocked, so adhering components are suppressed and the molding material has a high It has high quality and can be used in a variety of fields, including home appliances, stationery, automobile parts, toys and sporting goods, medical supplies, and building and construction materials.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited to these Examples. Note that "parts" and "%" in the present invention represent "parts by mass" and "% by mass" unless otherwise noted.

<Molecular weight and molecular weight distribution>
The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn) were measured by GPC (gel permeation chromatography) and determined as a converted molecular weight using polystyrene as a standard substance. The measurement conditions are shown below.
GPC device: Showa Denko Shodex GPC-104
Column: The following columns were connected in series and used.
Showa Denko Shodex LF-404 2 pieces Showa Denko Shodex LF-G
Detector: RI (differential refractometer)
Measurement conditions: Column temperature 40℃
Eluent: Tetrahydrofuran Flow rate: 0.3 mL/min

<Acid value, hydroxyl value>
Acid value and hydroxyl value were measured in accordance with JIS K 0070 (1992).

<Manufacture of resin for primer>
[Synthesis Example 1-1] (Polyurethane resin P1)
PPA (a polyester consisting of a polycondensate of propylene glycol and adipic acid, with Mn 2,000 101.2 parts of PPG (polyether polyol with Mn 2,000, made of polypropylene glycol), 17.2 parts of DMPA (2,2-dimethylolpropanoic acid), and 101.2 parts of PPG (polyether polyol with Mn 2,000, consisting of polypropylene glycol), 17.2 parts of DMPA (2,2-dimethylolpropanoic acid), and IPDI (isophorone diisocyanate). ) and 140 parts of NPAC (n-propyl acetate) were charged and reacted at 90° C. for 5 hours to obtain a prepolymer solution having isocyanate groups at the ends.
Next, a mixture of 10.5 parts of AEA (2-(2-aminoethylamino)ethanol) and 245 parts of IPA (isopropyl alcohol) was added dropwise at room temperature over 60 minutes, and then reacted at 70°C for 3 hours. A polyurethane resin solution was obtained.
To the obtained polyurethane resin solution, 56 parts of NPAC and 49 parts of IPA were added to adjust the solid content to obtain a polyurethane resin with a solid content concentration of 30%, Mw 24,000, Mw/Mn = 3.4, and acid value 34.5 mgKOH/g. A solution of P1 was obtained.

[Synthesis Example 1-2] (Polyurethane resin P2)
104.4 parts of PPA, 10.4 parts of PPG, BD (1,4 -butanediol), 73.1 parts of IPDI, and 140 parts of NPAC were charged and reacted at 90°C for 5 hours to obtain a urethane prepolymer solution having isocyanate groups at the ends.
Next, a mixture of 10.3 parts of AEA and 245 parts of IPA was added dropwise at room temperature over 60 minutes, and then reacted at 70°C for 3 hours to obtain a polyurethane resin solution.
To the obtained polyurethane resin solution, 56 parts of NPAC and 49 parts of IPA were added to adjust the solid content, and a polyurethane resin P2 with a solid content concentration of 30%, Mw 23,000, Mw/Mn = 2.9, and acid value 0 mgKOH/g was prepared. A solution was obtained.

The abbreviations in Table 1 are shown below.
PPA: Polyester polyol with Mn 2,000, consisting of a polycondensate of propylene glycol and adipic acid PPG: Polyether polyol with Mn 2,000, consisting of polypropylene glycol DMPA: 2,2-dimethylolpropanoic acid BD: 1,4- Butanediol IPDI: Isophorone diisocyanate NPAC: Normal propyl acetate AEA: 2-(2-aminoethylamino)ethanol IPA: Isopropyl alcohol

<Composition for forming primer layer>
[Production Example 1-1] (Primer composition S1)
87 parts of polyurethane resin P1 solution, 5 parts of EA, 5 parts of IPA, and 3 parts of silica particles (P-73 manufactured by Mizusawa Chemical Co., Ltd.: hydrophilic silica particles with an average particle diameter of 3.8 μm) were stirred and mixed using a disper to form a primer composition. Product S1 was obtained.

[Production Examples 1-2 to 3] (Primer compositions S2, S3)
Primer compositions S2 and S3 were obtained in the same manner as in Production Example 1-1, except that the raw materials and blending ratios shown in Table 2 were changed.

The abbreviations in Table 2 are shown below.
Maleated rosin solution: Marquid No. manufactured by Arakawa Chemical Industry Co., Ltd. 32 (acid value 135 mgKOH/g, solid content concentration 100% product) was diluted with ethyl acetate to a solid content concentration of 30%.
PVA solution: 15% solids concentration aqueous solution of Kuraray Poval 5-88 (saponification degree 86.5-89.0%) manufactured by Kuraray.
EA: ethyl acetate

<Composition for forming an ink layer>
[Printing ink I1]
Printing ink composition I1 was obtained by stirring and mixing 95 parts of Rio Alpha R39 indigo (manufactured by Toyo Ink Co., Ltd.) and 5 parts of a maleated rosin solution using a disper. For the maleated rosin solution, Marquid No. manufactured by Arakawa Chemical Industry Co., Ltd. A solution prepared by diluting No. 32 (acid value 135 mgKOH/g, solid content concentration 100% product) with ethyl acetate to a solid content concentration of 30% was used.

[Printing ink I2]
Rio Alpha R39 indigo (manufactured by Toyo Ink Co., Ltd.) was used as printing ink I2.

<Manufacture of polyol used in adhesives>
[Synthesis Example 2-1] (Polyester polyol A1)
204 parts of ethylene glycol, 215 parts of neopentyl glycol, 210 parts of 1,6-hexanediol, 579 parts of isophthalic acid, and adipine were placed in a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping tank, and a nitrogen gas introduction tube. 61 parts of acid and 232 parts of sebacic acid were charged, and the temperature was raised to 250° C. with stirring under a nitrogen stream to perform an esterification reaction. After the reaction was continued until a predetermined amount of water was distilled out and the acid value became 5 or less, the pressure was gradually reduced and the deglycol reaction was performed at 1 mmHg or less for 5 hours to obtain a polyester polyol. Thereafter, 34 parts of isophorone diisocyanate was gradually added, and the reaction was carried out at 150° C. for about 2 hours to obtain a polyester polyurethane polyol. 13.0 parts of ethylene glycol bisanhydrotrimellitate was added to 100 parts of this polyester polyurethane polyol, reacted at 180°C for about 2 hours, and then diluted with ethyl acetate until the nonvolatile content was 50%. 500 and an acid value of 31.5 mgKOH/g, a partially acid-modified polyester polyol A1 solution was obtained.

[Synthesis Example 2-2] (Polyester polyol A2)
242 parts of ethylene glycol, 401 parts of neopentyl glycol, 404 parts of isophthalic acid, and 452 parts of adipic acid were charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping tank, and a nitrogen gas introduction pipe, and the mixture was heated under a nitrogen stream. The temperature was raised to 250° C. while stirring to perform an esterification reaction. After continuing the reaction until a predetermined amount of water was distilled out and the acid value became 5 or less, the pressure was gradually reduced and the deglycol reaction was carried out for 5 hours at 1 mmHg or less to obtain a polyester polyol. 3.5 parts of trimellitic anhydride was added to 100 parts of this polyester polyol, reacted at 180°C for about 2 hours, and then diluted with ethyl acetate until the nonvolatile content was 50%. A solution of .3 mgKOH/g of partially acid-modified polyester polyol A2 was obtained.

[Synthesis Example 2-3] (Polyester polyol A3)
166 parts of ethylene glycol, 279 parts of neopentyl glycol, 158 parts of 1,6-hexanediol, 278 parts of terephthalic acid, and isophthalic acid were placed in a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping tank, and a nitrogen gas introduction tube. 278 parts of acid, 56 parts of adipic acid, and 285 parts of sebacic acid were charged, and the temperature was raised to 250° C. with stirring under a nitrogen stream to perform an esterification reaction. After the reaction was continued until a predetermined amount of water was distilled out and the acid value became 5 or less, the pressure was gradually reduced and the deglycol reaction was performed at 1 mmHg or less for 5 hours to obtain a polyester polyol. Thereafter, 7.5 parts of isophorone diisocyanate was gradually added, and the reaction was carried out at 150° C. for about 2 hours to obtain a polyester polyurethane polyol. 0.7 parts of trimellitic anhydride was added to 100 parts of this polyester polyurethane polyol, reacted at 180°C for about 2 hours, and then diluted with ethyl acetate until the solid content concentration was 50%. A solution of partially acid-modified polyester polyol A3 having a value of 2.1 mgKOH/g was obtained.

<Manufacture of high acid value resin>
(High acid value resin H1)
Arakawa Chemical Marquid No. 32 (acid value 135 mgKOH/g, solid content concentration 100% product) was diluted with ethyl acetate to a solid content concentration of 30% to obtain a solution of high acid value resin H1.

(High acid value resin H2)
200 parts of toluene was charged into a reaction vessel equipped with a stirrer, a temperature system, a reflux condenser, a dropping tank, and a nitrogen gas introduction tube, and the temperature was raised to 110° C. while stirring while introducing nitrogen gas. Next, 80 parts of methyl methacrylate, 50 parts of butyl acrylate, 100 parts of maleic anhydride, and 50 parts of toluene were charged into the dropping tank 1, and a solution of 9 parts of benzoyl peroxide dissolved in 50 parts of toluene was charged into the dropping tank 2. The mixture was simultaneously added dropwise over 2 hours with stirring while maintaining the temperature inside the reaction vessel at 110°C. After the reaction, the polymer was cooled to room temperature, precipitated with a large amount of methanol, filtered, and dried at 120°C for 6 hours to form a (meth)acrylic ester and maleic anhydride with a weight average molecular weight of 2,300 and an acid value of 465 mgKOH/g. A resin was obtained by copolymerizing with an acid. Then, the solution was diluted with ethyl acetate to a solid content concentration of 30% to obtain a solution of high acid value resin H2.

<Adjustment of polyisocyanate>
(Polyisocyanate C1)
Coronate 2785 (biuret type polyisocyanate derived from hexamethylene diisocyanate, manufactured by Tosoh Corporation) was diluted with ethyl acetate to adjust the non-volatile content to 50% and NCO% = 9.6% to obtain a solution of polyisocyanate C1. Ta.

<Composition for forming adhesive layer>
[Production Example 2-1] (Adhesive T1)
90 parts of polyester polyol A1 solution, 10 parts of polyester polyol A2 solution, and 8 parts of polyisocyanate C1 solution were blended, and ethyl acetate was added to obtain a solution of adhesive T1 with a solid content concentration of 30%.

[Production Examples 2-2 to 4] (Adhesive T2 to 4)
Solutions of adhesives T2 to T4 were obtained in the same manner as in Production Example 2-1, except that the raw materials and composition shown in Table 3 were changed.

<Manufacture of laminated film>
The method for manufacturing the laminated film will be described below. Table 4 shows the structure of the laminated film and the types of primer, ink, and adhesive. The resin base layer to be recovered is underlined. Furthermore, the notation "-" in Table 4 indicates that the configuration does not exist.
The primer composition (excluding primer composition S3) and printing ink were each made using a mixed solvent of EA/IPA (mass ratio 70/30) and had a viscosity of 15 seconds (25°C, Zahn cup #3 (25°C, Zahn cup #3). (manufactured by Rigosha)) before use. Further, the thicknesses of the primer layer and the ink layer were each adjusted to about 1.5 μm. Primer composition S3 was adjusted to have the same viscosity and thickness except that water was used as the dilution solvent.

[Production Example 3-1] (Laminated film L1)
The diluted primer composition S1 and printing ink I2 were printed on the entire surface of OPP (corona-treated stretched polypropylene film, thickness 20 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm. It was dried at .degree. C. to obtain a laminated film L1 having a structure of base material layer (OPP)/release primer layer (S1)/ink layer (I2).

[Production Examples 3-2, 3-3] (Laminated films L2, L3)
Laminated films L2 and L3 were obtained in the same manner as in Production Example 3-1, except that the base material and primer composition were changed to those listed in Table 4.

[Production Example 3-4] (Laminated film L4)
The diluted printing ink I1 was printed on the entire surface of OPP (thickness 20 μm) using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50°C to form the base layer (OPP)/desorption. A laminated film L4 having the structure of the ink release layer (I1) was obtained.

[Production Example 3-5] (Laminated film L5)
On OPP (thickness 20 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a configuration of OPP/S1/I2 was obtained.
Next, on the ink layer of the obtained laminated film, adhesive T1 was applied and dried using a dry laminating machine so that the coating amount after drying was 2.5 g/m ² , and then CPP (unstretched polypropylene film) was applied. 25 μm thick).
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (OPP)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (CPP). ) was obtained.

[Production Examples 3-6 to 3-9] (Laminated films L6 to 9)
Laminated films L6 to L9 were obtained in the same manner as in Production Example 3-5, except that the base material, primer composition, and adhesive were changed to those listed in Table 4.

[Production Example 3-10] (Laminated film L10)
The diluted printing ink I1 was printed on the entire surface of OPP (thickness 20 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50° C. to form OPP/I1. A laminated film was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 2.5 g/m ² , and after drying, CPP (thickness: 25 μm) was applied. Pasted together.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a laminated film having the following composition: base material layer (OPP)/release ink layer (I1)/release adhesive layer (T1)/base material layer (CPP). A film L10 was obtained.

[Production Example 3-11] (Laminated film L11)
For OPP (thickness 20 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a configuration of OPP/S1/I2 was obtained.
Next, adhesive T1 was coated and dried on the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 2.5 g/ ^m2 , and then LLDPE (Linear Low It was bonded to a density polyethylene film (thickness: 30 μm).
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (OPP)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (LLDPE). ) was obtained.

[Production Example 3-12] (Laminated film L12)
Diluted primer composition S1 and printing ink I2 were printed on the entire surface of NY (nylon film, thickness 15 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of NY/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, LLDPE (thickness: 80 μm) was applied. Pasted together.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base layer (NY)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base layer (LLDPE). ) was obtained.

[Production Example 3-13] (Laminated film L13)
For NY (thickness 25 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of NY/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, LLDPE (thickness 150 μm) was applied. Pasted together.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base layer (NY)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base layer (LLDPE). ) was obtained.

[Production Example 3-14] (Laminated film L14)
The diluted printing ink I2 was printed on the entire surface of NY (thickness 25 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50°C to obtain the composition of NY/I1. A laminated film was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, LLDPE (thickness 150 μm) was applied. Pasted together.
Next, the obtained laminated film was kept warm at 40° C. for 3 days to form a laminated film L14 having the structure of base material layer (NY)/ink layer (I2)/release adhesive layer (T1)/base material layer (LLDPE). I got it.

[Production Example 3-15] (Laminated film L15)
The diluted primer composition S1 and printing ink I2 were printed on the entire surface of PET (polyethylene terephthalate film, thickness 12 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. As a result, a laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, LLDPE (thickness 40 μm) was applied. Pasted together.
Next, the obtained laminated film was kept at 40° C. for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (LLDPE). ) was obtained.

[Production Example 3-16] (Laminated film L16)
For NY (thickness 15 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of NY/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, CPP (thickness 70 μm) was applied. Pasted together.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (NY)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (CPP). ) was obtained.

[Production Example 3-17] (Laminated film L17)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, NY (thickness: 15 μm) was applied. Pasted together.
Next, adhesive T1 was applied to the nylon film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with CPP (thickness 70 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (NY )/removable adhesive layer (T1)/base material layer (CPP) laminated film L17 was obtained.

[Production Example 3-18] (Laminated film L18)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, NY (thickness: 15 μm) was applied. Pasted together.
Next, adhesive T1 was applied to the nylon film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with LLDPE (thickness 100 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (NY ) / release adhesive layer (T1) / base material layer (LLDPE) was obtained.

[Production Example 3-19] (Laminated film L19)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, NY (thickness: 15 μm) was applied. Pasted together.
Next, adhesive T1 was applied to the nylon film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with LLDPE (thickness 150 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (NY ) / release adhesive layer (T1) / base material layer (LLDPE) was obtained.

[Production Example 3-20] (Laminated film L20)
The diluted primer composition S1 and printing ink I2 were printed on the entire surface of transparent silica-deposited PET (thickness 12 μm) in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm. It was dried at °C to obtain a laminated film having a structure of PET/silica vapor deposited layer/S1/I2.
Next, adhesive T1 was applied onto the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and after drying, NY (thickness: 15 μm) was applied. Pasted together.
Next, adhesive T1 was applied to the nylon film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with CPP (thickness 70 μm). Ta.
Next, the obtained laminated film was kept at 40° C. for 3 days to form a base material layer (silica-deposited PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer. A laminated film L20 having a structure of (NY)/removable adhesive layer (T1)/base material layer (CPP) was obtained.

[Production Example 3-21] (Laminated film L21)
On OPP (thickness 20 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a configuration of OPP/S1/I2 was obtained.
Next, adhesive T1 was coated and dried on the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and transparent silica-deposited PET (thickness 12 μm) was bonded to the vapor-deposited surface.
Next, adhesive T1 was applied to the PET film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with CPP (thickness 30 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days, and the base material layer (OPP)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (silica A laminated film L21 having a structure of vapor-deposited PET)/removable adhesive layer (T1)/base material layer (CPP) was obtained.

[Production Example 3-22] (Laminated film L22)
For OPP (thickness 20 μm), diluted primer composition S1 and printing ink I2 were printed on the entire surface in this order using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a configuration of OPP/S1/I2 was obtained.
Next, on the ink layer of the obtained laminated film, adhesive T1 was applied and dried using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and then aluminum (AL) vapor-deposited PET was applied. (thickness: 12 μm).
Next, adhesive T1 was applied to the PET film surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with CPP (thickness 25 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (OPP)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (aluminum). A laminated film L22 having a structure of vapor-deposited PET)/removable adhesive layer (T1)/base material layer (CPP) was obtained.

[Production Example 3-23] (Laminated film L23)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was coated and dried on the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ^{2 .} ) was attached to the vapor-deposited surface.
Next, adhesive T1 was applied to the aluminum vapor-deposited surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with LLDPE (thickness 150 μm). Ta.
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (aluminum). A laminated film L23 having a structure of vapor-deposited PET)/removable adhesive layer (T1)/base material layer (LLDPE) was obtained.

[Production Example 3-24] (Laminated film L24)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, on the ink layer of the obtained laminated film, adhesive T4 was applied and dried using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and then AL (aluminum foil, thickness 7 μm) was applied. ) was attached.
Next, adhesive T1 was applied to the AL surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ^{2 ,} and after drying, it was bonded to CPP (thickness 70 μm). .
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base layer (PET)/release primer layer (S1)/ink layer (I2)/adhesive layer (T4)/base layer (AL)/ A laminated film L24 having a composition of a releasable adhesive layer (T1)/base material layer (CPP) was obtained.

[Production Example 3-25] (Laminated film L25)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, on the ink layer of the obtained laminated film, adhesive T4 was applied and dried using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and then AL foil (thickness 7 μm) was applied. Pasted with.
Next, adhesive T1 was applied to the AL surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was bonded to NY (thickness: 15 μm). .
Next, adhesive T1 was applied to the NY surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ^{2 ,} and after drying, it was laminated with CPP (thickness: 70 μm). .
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base layer (PET)/release primer layer (S1)/ink layer (I2)/adhesive layer (T4)/base layer (AL foil). A laminated film L25 having the following composition was obtained: /removable adhesive layer (T1)/base material layer (NY)/releasable adhesive layer (T1)/base material layer (CPP).

[Production Example 3-26] (Laminated film L26)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, on the ink layer of the obtained laminated film, adhesive T4 was applied and dried using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and then AL foil (thickness 7 μm) was applied. Pasted with.
Next, adhesive T1 was applied to the AL surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was bonded to NY (thickness: 15 μm). .
Next, adhesive T1 was applied to the NY surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with LLDPE (thickness 100 μm). .
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base layer (PET)/release primer layer (S1)/ink layer (I2)/adhesive layer (T4)/base layer (AL foil). A laminated film L26 having the following composition was obtained: /Releasable adhesive layer (T1)/Base material layer (NY)/Releasable adhesive layer (T1)/Base material layer (LLDPE).

[Production Example 3-27] (Laminated film L27)
PET (thickness 12 μm) was printed with diluted primer composition S1 and printing ink I2 in this order on the entire surface using a gravure printing machine equipped with a gravure plate with a plate depth of 30 μm, and dried at 50 ° C. A laminated film having a structure of PET/S1/I2 was obtained.
Next, adhesive T1 was coated and dried on the ink layer of the obtained laminated film using a dry laminating machine so that the coating amount after drying was 3.0 g/m ² , and then aluminum vapor-deposited PET (thickness 12 μm ) was attached to the vapor-deposited surface.
Next, adhesive T1 was applied to the PET surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ^{2 ,} and after drying, it was bonded to NY (thickness: 15 μm). .
Next, adhesive T1 was applied to the NY surface of the obtained laminated film in the same manner as before so that the coating amount after drying was 3.0 g/m ² , and after drying, it was laminated with LLDPE (thickness 70 μm). .
Next, the obtained laminated film was kept warm at 40°C for 3 days to form a base material layer (PET)/release primer layer (S1)/ink layer (I2)/release adhesive layer (T1)/base material layer (aluminum). A laminated film L27 having a structure of vapor-deposited PET)/release adhesive layer (T1)/base material layer (NY)/release adhesive layer (T1)/base material layer (LLDPE) was obtained.

Abbreviations in Table 4 are shown below.
Transparent vapor-deposited PET: Transparent silica-deposited PET
VMPET: Aluminum vapor deposited PET

<Separation and recovery method of laminated film>
The conditions of steps (1) and (4) in Tables 5 to 7 will be explained below. Note that in all Examples and Comparative Examples, laminated films cut into a size of 35 cm x 35 cm were used.

[Step (1)]
(Shredding device)
Wet method (1): Model PFS-40 manufactured by Nippon Seam (vertical shredding device equipped with a cutter mill and a circular screen with a diameter of 15 mm). The shredding process was performed while water was flowing in from the water inlet.
Wet method (2): Nikuni Suncutter C80H (horizontal shredding device equipped with a cutter mill and a circular screen with a diameter of 15 mm) was used. In this specification, shredding of the laminated film and separation of the resin base layer were simultaneously performed while a 2% by mass aqueous sodium hydroxide solution was flowing in from the water inlet.
Dry type: Horai FG-2060 (equipped with a cutter mill and a circular screen with a diameter of 15 mm).

(Mass of laminated film)
The mass of laminated film fed into the shredding device from the laminated film input port in one minute.

(mass of water)
Mass of water input from the water inlet of the shredding device in one minute.

(Water cooling temperature)
Temperature of water input from the water inlet of the shredding device.

[Step (4)]
(Washing filtration process)
In the washing and filtration step, a washing and filtration device (model SW-408 manufactured by Nippon Seam Co., Ltd.) equipped with a circular filtration screen with a diameter of 3 mm was connected to the shredding device, and water washing and filtration were performed continuously.

[Example 1]
1.2 kg of laminated film L1 (35 cm x 35 cm) was fed into a wet shredding device (wet type (1)) equipped with a circular screen with a diameter of 15 mm at a rate of 1.2 kg/min, and the temperature was raised to 20 kg using a cooling device. After shredding while adding water controlled at a temperature of 60 kg/min, the shredded material was passed through the screen to obtain shredded material (step (1)). The long side of the obtained shredded material was 15 mm or less.
Next, the shredded material is transported to a washing filtration device (SW-408 model manufactured by Nippon Seam) that is directly connected to the shredding device, and the shredded material is washed with water to remove fine pieces with a diameter of 3 mm or less that are generated during shredding. (Step (4)).
Next, 1500 ml of a 2% by mass aqueous sodium hydroxide solution at 70° C. was added into a 2000 ml flask, and 30 g of the obtained shredded material was immersed. The mixture was stirred at 70° C. and 200 rpm for 2 hours to separate the resin base layer (step (2)).
Next, the separated resin base material layer (OPP) was collected using a specific gravity sorting method, washed with water, and dried (step (3)).

[Examples 2-6, Examples 11-40, Comparative Examples 1-2, Comparative Examples 4-9]
The laminated film was separated and recovered in the same manner as in Example 1, except that the type of laminated film and the conditions of steps (1) and (4) were changed to those listed in Tables 5 and 7. In addition, when the separated resin base material layer was olefin, it was collected using a specific gravity selection method, and when it was PET or NY, it was collected using a filter, washed with water, and dried.

[Example 7]
1.2 kg of laminated film L3 (35 cm x 35 cm) was fed into a wet shredding device (wet type (1)) equipped with a circular screen with a diameter of 15 mm at a rate of 1.2 kg/min, and the temperature was raised to 20 kg using a cooling device. The mixture was shredded while adding water controlled at a temperature of 60 kg/min at a rate of 60 kg/min, and then passed through the screen to obtain shredded products (step (1)). The long side of the obtained shredded material was 15 mm or less.
Next, the shredded material is transported to a washing filtration device (model SW-408 manufactured by Nippon Seam) that is directly connected to the shredding device, and the shredded material is washed with water to remove fine pieces with a diameter of 3 mm or less that are generated during shredding. (Step (4)).
Next, 1500 ml of water at 70° C. was added to a 2000 ml flask, and 30 g of the obtained shredded material was immersed. The mixture was stirred at 70° C. and 200 rpm for 2 hours to separate the resin base layer (step (2)).
Next, the separated resin base material layer (OPP) was collected using a specific gravity sorting method, washed with water, and dried (step (3)).

[Examples 8 to 10, Comparative Example 3]
The laminated film was separated and recovered in the same manner as in Example 7, except that the type of laminated film and the conditions of steps (1) and (4) were changed to those listed in Table 6.

[Comparative Example 10]
1.2 kg of laminated film L5 (35 cm x 35 cm) was fed into a wet shredding and separation device (wet type (2)) equipped with a circular screen with a diameter of 15 mm at a rate of 1.2 kg/min, and was heated using a cooling device. A 2% by mass aqueous sodium hydroxide solution controlled at a temperature of 20° C. was added at a rate of 60 kg/min, and the resin base material layer was separated at the same time as shredding, and then passed through the above screen to separate the resin base material layer from the shredded material. I got it. The long side of the obtained resin base material layer was 15 mm or less.
Next, the separated resin base material layer (OPP, CPP) was collected using a specific gravity sorting method, washed with water, and dried.

[Comparative Example 11]
The laminated film was separated and recovered in the same manner as in Comparative Example 10, except that the conditions for the shredding and separation steps were changed to those listed in Table 7.

<Evaluation of recovered resin base material layer>
The recovered resin base material was evaluated for ink releasability and removal rate. For laminated films bonded together using an adhesive, lamination releasability and adhesive removal rate were evaluated. The results are shown in Tables 5-7.

(Ink releasability)
For examples using a laminated film having a release primer layer and/or release ink layer on the base material, the base material on which the release primer layer and/or release ink layer was printed after separation was randomly printed. Ten sheets were sampled, and the desorption area of the ink layer was visually confirmed and evaluated based on the following criteria. As for the evaluation criteria, 3 or more is in the usable range.
5 (Excellent): Peeling area is 90% or more 4 (Good): Peeling area is 80% or more and less than 90% 3 (Acceptable): Peeling area is 60% or more and less than 80% 2 (Poor): Peeling area is 20% or more % or more and less than 60% 1 (impossible): Peeling area is less than 20%

(Primer and ink removal rate)
For the 10 substrates used to evaluate the releasability of the ink, FT-IR was measured at two locations per substrate to confirm the presence or absence of absorption peaks derived from the primer or ink. The rate at which no absorption peak was detected (removal rate) at a total of 20 locations was calculated and evaluated based on the following criteria. For example, if no absorption peak is detected at 19 out of 20 locations, the removal rate is 95%. As for the evaluation criteria, 3 or more is in the usable range.
5 (Excellent): Removal rate is 90% or more 4 (Good): Removal rate is 80% or more and less than 90% 3 (Acceptable): Removal rate is 60% or more and less than 80% 2 (Poor): Removal rate is 20% % or more and less than 60% 1 (impossible): Removal rate is less than 20%

(Adhesive removal rate)
For examples using laminated films with a release adhesive layer, 10 substrates to be collected that are in contact with the release adhesive layer were randomly sampled, and FT-IR was measured at two locations per substrate. The presence or absence of an absorption peak derived from the adhesive was confirmed. The rate at which no absorption peak was detected (removal rate) at a total of 20 locations was calculated and evaluated based on the following criteria. For example, if no absorption peak is detected at 19 out of 20 locations, the removal rate is 95%. As for the evaluation criteria, 3 or more is in the usable range.
5 (Excellent): Removal rate is 90% or more 4 (Good): Removal rate is 80% or more and less than 90% 3 (Acceptable): Removal rate is 60% or more and less than 80% 2 (Poor): Removal rate is 20% % or more and less than 60% 1 (impossible): Removal rate is less than 20%

(Lamination removability)
For examples using laminated films with a release adhesive layer, randomly sample 30 collection target substrates that are in contact with the release adhesive layer, and calculate the number of laminated films in which the base materials have not peeled from each other. It was confirmed and evaluated based on the following criteria. As for the evaluation criteria, 3 or more is in the usable range.
5 (Excellent): 1 or less laminated films that have not peeled off 4 (Good): 2 to 3 laminated films that have not peeled off 3 (Acceptable): 4 to 6 laminated films that have not peeled off 2 (Not good) ): 7 to 15 laminated films that have not been peeled 1 (not possible): 16 or more laminated films that have not been peeled

From the above evaluation results, the laminate obtained by shredding while cooling with water at a liquid temperature of 50°C or less by continuously adding water at a temperature of 50°C or less during the shredding process has a fine cross-section. The exposure of the release layer was maintained, and the resin base material layer could be efficiently separated and recovered.
In particular, when the mass of water used in the shredding step was 2 or more based on the mass of the laminated film, the lamination releasability was improved. This is presumed to be due to the fact that film fusion during shredding was suppressed, exposing the fine cross section, and efficient separation of the resin base material proceeded (Examples 11, 14 to 16).
In addition, by having a washing and filtration step after the shredding step, fine pieces of ink and adhesive components generated in the shredding step are removed and adhesion to the substrate is suppressed, so in the subsequent separation step, The separation and recovery properties of the resin base material were excellent (Examples 11 and 18).
On the other hand, when a dry shredding device (dry type) is used, the laminated films fuse together during shredding, and the desorption liquid does not penetrate into the laminated film in the subsequent separation process, reducing the separation and recovery performance of the resin base material. (Comparative Examples 1 to 3, 5 to 9).
When using a wet shredding device (wet type (2)) that performs the shredding process and the separation process at the same time, the residence time of the laminated film was short, so that sufficient desorption was not achieved. Furthermore, fine pieces of ink and adhesive components generated during shredding adhered to the substrate, resulting in a reduction in removal rate (Comparative Examples 10 and 11).

Claims (9)

A method for separating and recovering a laminated film having at least a resin base layer and a release layer, the method comprising the following steps (1) to (3).
(1) A shredding step in which the laminated film is shredded while being cooled with water at a liquid temperature of 50° C. or lower using a cooling means to obtain shredded products. (2) A shredding step in which the shredded material is immersed in a desorption liquid. , separation step of separating the resin base layer (3) recovery step of recovering the separated resin base layer The method for separating and recovering a laminated film according to claim 1, further comprising the following step (4) between the step (1) and the step (2).
(4) Washing and filtration step in which the shredded material is washed with water to remove fine pieces. The method for separating and recovering a laminated film according to claim 2, wherein the step (4) includes filtering using a filter screen. The method for separating and recovering a laminated film according to any one of claims 1 to 3, wherein the mass of water used in the shredding step is 2 to 500 times the mass of the laminated film. The method for separating and recovering a laminated film according to any one of claims 1 to 3, wherein the release layer is a layer containing a compound having an acidic group. The method for separating and recovering a laminated film according to any one of claims 1 to 3, wherein the release layer is a layer containing a water-soluble resin. The laminated film according to any one of claims 1 to 3, wherein the laminated film has a partial structure comprising a resin base layer, a primer layer, and an ink layer in this order, and the primer layer is a release layer. Separation and recovery method. The laminated film according to any one of claims 1 to 3, wherein the laminated film has a partial structure in which two resin base layers are laminated with an adhesive layer interposed therebetween, and the adhesive layer is a release layer. Separation and recovery method for laminated films. Separation and recovery of the laminated film according to any one of claims 1 to 3, wherein the laminated film has a partial structure comprising a resin base layer and an ink layer in this order, and the ink layer is a release layer. Method.