WO2021070096A1

WO2021070096A1 - Laminate

Info

Publication number: WO2021070096A1
Application number: PCT/IB2020/059444
Authority: WO
Inventors: 太田匡彦; 尾下竜也; 小鷹昭広; 野中康弘
Original assignee: プランティック・テクノロジーズ・リミテッド
Priority date: 2019-10-08
Filing date: 2020-10-08
Publication date: 2021-04-15
Also published as: JP2021059080A; JPWO2021070096A1

Abstract

A laminate according to the present invention comprises a remoistening adhesive agent layer (I) and a base material layer (II), the remoistening adhesive agent layer (I) containing a modified starch (A) and a water-soluble polymer (B), and the modified starch (A) having an amylose content of at least 45 mass%.

Description

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1 Detailed book Invention title: Laminated body technology field

[0001] The present invention relates to a laminate containing a re-wet adhesive layer used for food packaging and the like, a multilayer laminate and an adhesive containing the laminate, a bag made of the adhesive, and a label made of the laminate. , Tapes and lids, and other packaging materials and auxiliary materials for packaging. Background technique

[0002] In food packaging, for sealing the contents, there are a method of melt-adhering seal layers such as heat seal and ultrasonic seal, and a method of joining with an adhesive material such as hot melt adhesive. is there. One of them is a sealing method using a re-wet-adhesive layer represented by stamps, which is mainly used as a packaging auxiliary material. For example, as the re-wet adhesive layer, one using an acrylic polymer (Japanese Patent Application Laid-Open No. 1) and one using polyvinyl alcohol as a main component (Patent Document 2) are known. In addition, in food packaging, functions such as gas barrier properties are required to maintain the freshness of foods, and the demand for biodegradability of packaging materials has increased remarkably from the viewpoint of responding to environmental problems in recent years. ing. Prior technical literature Patent text

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2 0 1 8 --0 9 0 3 1 9 Patent Document 2: Japanese Patent Application Laid-Open No. 6 1 --- 3 9 3 5 4 Outline of Invention Outline of Invention Problem to be Solved by Invention

[0004] However, although synthetic polymers such as polyvinyl alcohol have high strength, there is a problem that the biodegradability particularly required for packaging materials in recent years cannot be satisfied. On the other hand, starch, which is most often used as a re-wet adhesive layer, has relatively high biodegradability and can be softened and dissolved in the presence of water. However, according to the study of the present inventor, the re-moisture adhesive layer is particularly 20 to 4 in the humidity environment in which the food packaging material is placed. 〇 2021/070096 卩 (: 17132020/059444

2

It was found that sufficient adhesive strength could not be obtained because it became extremely embrittled in a low humidity environment of 0% [¾ 1 ^{to 1.}

[0005] An object of the present invention is a laminate having high biodegradability and excellent adhesive strength even when exposed to a low humidity environment, a multilayer laminate including the laminate and an adhesive, and the contact. It is an object of the present invention to provide a bag made of a body, and a label, a tape and a lid material made of the laminated body. Means to solve problems

[0006] As a result of diligent studies to solve the above problems, the present inventor has made a re-wet adhesive layer.

In the laminate containing [1] and the base material layer (II), the re-wet adhesive layer (I) contains the modified starch (8) and the water-soluble polymer _ (Snake), and the modified starch (8) We have found that the above problems can be solved when the content of amylose is 45% by mass or more, and have completed the present invention. That is, the present invention includes the following aspects.

[0007] [1] A laminate containing a re-wet adhesive layer (I) and a base material layer (II), wherein the re-wet adhesive layer (I) is a modified starch () and a water-soluble polymer _ ( A laminate containing the modified starch (8) and having an amylose content of 45% by mass or more.

[2] The laminate described in [1], wherein the water-soluble polymer (Snake) is polyvinyl alcohol.

[3] Based on the total of 100 parts by mass of the modified starch () and the water-soluble polymer _ (Snake), the content of the modified starch () is 40 to 98 parts by mass, and the water-soluble polymer (water-soluble polymer) ( The laminate according to [1] or [2], wherein the content of starch) is 2 to 60 parts by mass.

[4] The laminate according to any one of [1] to [3], wherein the base material layer (II) is paper.

[5] A multi-layered laminate containing the laminate and layer (III) according to any one of [1] to [4], with the re-wet adhesive layer (I) of the laminate on the outermost surface. Has a multi-layer laminate 〇 2021/070096 卩 (: 17132020/059444

3

[6] An adhesive in which the re-wet adhesive layer (I) of the laminate according to any one of [1] to [5] and the adherend layer are re-wet-bonded, and the adherend layer is It is contained in the re-wet adhesive layer (I) contained in the laminated body or other laminated body, the layer selected from the base material layer (II) and the layer (III), or the adherend other than these laminated bodies. An adhesive that is a layer.

[7] The adhesive according to [6], wherein the adherend layer is a re-wet-adhesive layer (I) contained in the laminate or the other laminate.

[8] A bag made of the adhesive according to [6] or [7].

[9] A label composed of the laminate according to any one of [1] to [5], and the outermost surface of the laminate opposite to the re-wet adhesive layer (I) is printed. , Label

[1 0] A tape composed of the laminate according to any one of [1] to [5].

[1 1] A lid material made of the laminate according to any one of [1] to [5].

[1 2] The method for producing an adhesive according to [6], wherein at least the re-wet adhesive layer (I) of the laminate is re-moistened, and the re-wet adhesive layer (I) and the subject are covered. A method that includes the step of re-wet bonding with a layer. Effect of the invention

[0008] The laminate of the present invention is highly biodegradable and can have excellent adhesive strength even when exposed to a low humidity environment. A brief description of the drawing

[0009] [Fig. 1] Fig. 1 is a schematic view showing a layer structure of a laminated body according to an embodiment of the present invention.

[Fig. 2] Fig. 2 is a schematic view showing an adhesive (bag) according to an embodiment of the present invention and a method for producing the same.

[Fig. 3] Fig. 3 is a schematic view showing an adhesive (bag) according to an embodiment of the present invention and a method for producing the same.

[Fig. 4] Shows a schematic view of the twin-screw extruder used in the examples. Form for carrying out the invention

[0010] [Laminate] The laminate of the present invention is a laminate containing a re-wet adhesive layer (I) and a base material layer (II). \\ 0 2021/070096 卩 (: 17162020/059444)

4

<Re-wet adhesive layer (I)> The re-wet adhesive layer (I) is a layer that can be adhered by applying water. The laminate of the present invention can adhere the re-wet adhesive layer (I) at least partially by applying water.

[0011] The re-wet adhesive layer (I) contains the modified starch () and the water-soluble polymer _ (Snake), and the amylose content of the modified starch (8) is 45% by mass or more. Therefore, the laminate of the present invention is highly biodegradable and can have excellent adhesive strength even when exposed to a low humidity environment. Furthermore, it can also have an excellent gas barrier property. In the present specification, the adhesive strength indicates the adhesive strength when the re-wet adhesive layer is adhered to the adherend (adhesive layer) by re-wetting. Further, in the present specification, re-wetting means moistening (or wetting) the re-wetting adhesive layer with water, and re-wetting means moistening (or wetting) the re-wetting adhesive layer with water. After that, it means to bond.

[0012] (Modified starch (8)) As the modified starch (8), at least one selected from the group consisting of, for example, etherified starch, esterified starch, cationized starch and crosslinked starch may be used. it can.

[0013] Starches derived from potatoes, corn, potatoes, sweet potatoes, sago, evening pioka, morokoshi, beans, warabi, hass, hisashi, wheat, rice, sardines, kudzu corn, peas, etc. Be done. Among them, starch derived from corn and corn is preferable, and starch derived from high amylose corn is more preferable. Starch can be used alone or in combination of two or more.

[0014] Examples of the etherified starch include alkyl etherified starch such as methyl etherified starch; carboxyalkyl etherified starch such as carboxymethyl etherified starch; for example, hydroxyalkyl having 2 to 6 carbon atoms. Hydroxyalkyls such as etherified starch with groups 〇 2021/070096 卩 (: 17132020/059444

5 Ruethered starch; etc. In addition, allyl etherified starch and the like can also be used.

[0015] Examples of the esterified starch include esterified starch having a structural unit derived from a carboxylic acid such as esterified starch having a structural unit derived from acetic acid; and esterified starch having a structural unit derived from maleic acid anhydride, for example. Esterified starch having structural units derived from phthalic acid anhydride, esterified starch having structural units derived from octenyl succinate anhydride, esterified starch having structural units derived from octenyl succinic acid anhydride, etc. Examples thereof include esterified starch having a structural unit derived from xoic acid, such as denpun, phosphoric acid esterified starch, and urea phosphate esterified starch. Other examples include xanthate esterified starch, acetoacetic esterified starch and the like.

[0016] Examples of the cationized starch include a reaction product of starch and 2-diethylaminoethyl chloride, and a reaction product of starch and 2, 3-—epoxypropyltrimethylammonium chloride.

[0017] Examples of the crosslinked starch include formaldehyde crosslinked starch, epichlorohydrin crosslinked starch, phosphoric acid crosslinked starch, achlorine crosslinked starch and the like.

[0018] Modified starch (8) includes etherified starch having a hydroxyalkyl group having 2 to 6 carbon atoms, esterified starch having a structural unit derived from dicarboxylic acid anhydride, or a combination thereof. Preferably, hydroxyethyl etherified starch, hydroxypropyl etherified starch, hydroxybutyl etherified starch, esterified starch with structural units derived from maleic anhydride, esterified starch with structural units derived from phthalic acid anhydride, octet. Esterified starch having a structural unit derived from nyrsuccinic acid anhydride, or a combination thereof is more preferable. The modified starch (8) can be used alone or in combination of two or more.

[0019] The modified starch (8) has an amylose content of 4 in the modified starch (8). 〇 2021/070096 卩 (: 17132020/059444

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5 Mass% or more. Surprisingly, the present inventor found that the amylose content in the modified starch (8) contained in the re-wet adhesive layer (I) was 45% by mass or more, even when exposed to a low humidity environment. , Found to have excellent adhesive strength. Furthermore, when the amylose content is 45% by mass or more, it is advantageous from the viewpoint of gas barrier property and biodegradability. On the other hand, if the content of the amylose is less than 45% by mass, it is difficult to show sufficient adhesive strength in a low humidity environment. When two or more types of modified starch are used, the amylose content of the modified starch () means the average amylose content obtained by weighted averaging the amylose content of two or more types of modified starch. In this case, if the average amylose content is 45% by mass or more, the modified starch having an amylose content of less than 45% by mass may be contained.

[0020] The content of amylose in the modified starch (8) is preferably 50% by mass or more, more preferably 55% by mass or more, and further preferably 60% by mass or more. When the content of amylose in the modified starch (8) is equal to or higher than the above lower limit, it is easy to increase the adhesive strength in a low humidity environment, and it is easy to improve the gas barrier property and the biodegradability. The content of amylose in the modified starch () is usually 90% by mass or less. In addition, in this specification, the amylose content is an example.

It can be measured by the iodine coloring method described above.

[0021] The modified starch () has a water content of preferably 10 to 15% by mass in the modified starch ().

[0022] The etherified starch having a hydroxyalkyl group having 2 to 6 carbon atoms may be obtained by reacting starch with an alkylene oxide such as ethylene oxide, propylene oxide or petitrene oxide. The average number of hydroxy groups used for denaturation is preferably 0.05 to 2 per glucos unit in starch.

As the modified starch (8), commercially available ones can also be used. As an example of a typical commercial product of modified starch (8), for example, 丨 1 ^ 9 r & 6 \ 〇 11 companies 〇 2021/070096 卩 (: 17132020/059444

The hydroxypropyl etherified starch available from 7 is Mi 〇〇 I® (registered trademark).

[0024] (Water-soluble polymer (Snake)) The water-soluble polymer (Snake) is a polymer compatible with the modified starch (8). The water-soluble polymer (Snake) preferably has a melting point suitable for the processing temperature of the modified starch (8), and polyvinyl alcohol is preferable from the viewpoint of easily enhancing the adhesive strength and gas barrier property in a low humidity environment. The water-soluble polymer _ (Snake) can be used alone or in combination of two or more.

[0025] The degree of saponification of polyvinyl alcohol is preferably 80 to 9.8 mol%. When the degree of saponification of polyvinyl alcohol is within the above range, it tends to be easy to increase the adhesive strength and gas barrier property in a low humidity environment. The degree of saponification is more preferably 85 mol% or more, further preferably 88 mol% or more, and particularly preferably 90 mol% or more. The degree of saponification indicates the mole fraction of the hydroxyl group with respect to the total of the hydroxyl group and the ester group in polyvinyl alcohol. Polyvinyl alcohol is produced, for example, by hydrolysis of vinyl acetate obtained by polymerization of vinyl acetate monomers.

[0026] Polyvinyl alcohol has a viscosity of a 4% aqueous solution of polyvinyl alcohol measured in accordance with 丨 3 1 8 8 0 3 at 20 ° 〇, preferably 1 to 5 0 〇 1 3 -3. .. When the viscosity of polyvinyl alcohol is within the above range, it tends to increase the adhesive strength and gas barrier property in a low humidity environment. The viscosity is more preferably 3 0 1 3 or more, further preferably 5 01 3-3 or more, more preferably 4 5 01 3-3 or less, still more preferably 3 5 01 3 or less.

[0027] Polyvinyl alcohol can further contain other monomeric units other than vinyl alcohol units. Examples of other monomer units include monomer units derived from ethylenically unsaturated monomers. Ethylene unsaturated monomers include ethylene, propylene, 1 ^ _butene, isoptylene, 1-hexene and other << — olefins; acrylic acid and its salts; non-residual compounds having an acrylic acid ester group. 〇 2021/070096 卩 (: 17132020/059444

8 Saturated monomer; Methacrylic acid and its salt; Unsaturated monomer having a methacrylic acid ester group; Acrylic acid, 1 \ 1 — Methylacrylic acid, 1 \ 1 — Ethylacrylic acid, 1 \ 1, 1 \ 1 _dimethylacrylic acid, diacetone acrylic acid, acrylicamide propanesulfonic acid and its salts, acrylicamidopropyl dimethylamine and its salts (for example, quaternary salts); methacrylic acid, 1 \ 1 _methylmethacrylic acid Amid, 1 \ 1 _ethylmethacrylic acid, methacrylic acid propansulfonic acid and its salt, methacrylicamidopropyldimethylamine and its salt (for example, quaternary salt); methylvinyl ether, ethylvinyl ether, _propylvinyl ether, 丨_ Propyl vinyl ether,

Petit vinyl ether, 丨 _ Petit vinyl ether,

Petit vinyl ether, dodecyl vinyl ether, stearyl vinyl ether, 2, 3 —diacetoxy — 1 — vinyl ethers such as vinyloxypropane; vinyl cyanide such as acrylonitrile and methacrylonitrile; vinyl halides such as vinyl chloride and vinyl fluoride Halogenized vinylidene such as vinylidene chloride and vinylidene fluoride; allyl compounds such as allyl acetate, 2,3-diacetoxy 1-allyloxypropane and allyl chloride; unsaturated dicarboxylic acids such as maleic acid, itaconic acid and fumaric acid And its salts or esters; vinylsilyl compounds such as vinyl trimetoxysilane, isopropenyl acetate; vinyl sacrifice, vinyl vinegar, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl versaticate, vinyl caproate, Examples thereof include vinyl ester compounds such as vinyl carlylate, vinyl laurate, vinyl palmitate, vinyl stearate, vinyl oleate, and vinyl benzoate. The content of the other monomer unit is preferably 10 mol% or less, more preferably 5 mol% or less.

[0028] The method for producing polyvinyl alcohol is not particularly limited. For example, a method of polymerizing a vinyl alcohol monomer and optionally another monomer and saponifying the obtained polymer to convert it into vinyl alcohol units can be mentioned. Examples of the polymerization method for polymerization include batch polymerization, semi-batch polymerization, continuous polymerization, semi-continuous polymerization and the like. 〇 2021/070096 卩 (: 17132020/059444

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.. Examples of the polymerization method include known methods such as a massive polymerization method, a solution polymerization method, a suspension polymerization method, and an emulsion polymerization method. Known methods can be applied to the polymerization of the polymer. For example, it can be carried out in a state where the polymer is dissolved in alcohol or hydrous alcohol. The alcohol that can be used at this time is, for example, a lower alcohol such as methanol or ethanol.

[0029] The re-wet adhesive layer (I) has a modified starch () content of 40 to 9 based on a total of 100 parts by mass of the modified starch () and the water-soluble polymer _ (Snake). It is preferably 8 parts by mass, and the content of the water-soluble polymer _ (snake) is preferably 2 to 60 parts by mass. When the content of the modified starch () and the content of the water-soluble polymer _ (Snake) are within the above ranges, it is easy to enhance the adhesive strength, biodegradability and gas barrier property in a low humidity environment.

[0030] The content of the modified starch () is preferably 45 parts by mass or more, more preferably 5 5 based on the total of 100 parts by mass of the modified starch () and the water-soluble polymer _ (Mi). It is 5 parts by mass or more, more preferably 65 parts by mass or more, preferably 95 parts by mass or less, more preferably 93 parts by mass or less, and further preferably 90 parts by mass or less. When the content of the modified starch (8) is at least the above lower limit, the biodegradability is likely to be improved, and when it is at least the above upper limit, the gas barrier property and the adhesive strength in a low humidity environment are easily improved.

[0031] The content of the water-soluble polymer _ (Mi) is preferably 5 parts by mass or more, more preferably 7 based on a total of 100 parts by mass of the modified starch () and the water-soluble polymer (Mi). It is 5 parts by mass or more, more preferably 10 parts by mass or more, preferably 55 parts by mass or less, more preferably 45 parts by mass or less, and further preferably 35 parts by mass or less. When the content of the water-soluble polymer _ (Snake) is at least the above lower limit, it is easy to improve the gas barrier property and the adhesive strength in a low humidity environment, and when it is at least the above upper limit, the biodegradability is improved. Cheap.

[0032] In the re-wet adhesive layer (I), the total ratio of the modified starch () and the water-soluble polymer _ (Snake) is preferably 10 relative to the mass of the re-wet adhesive layer (I). Mass% or more, more preferably 40% by mass or more, still more preferably 60% by mass or more 〇 2021/070096 卩 (: 17132020/059444

Ten

, Particularly preferably 80% by mass or more, and preferably 100% by mass or less. When the total ratio of the modified starch () and the water-soluble polymer _ (Snake) is within the above range, it is easy to enhance the adhesive strength, biodegradability and gas barrier property in a low humidity environment.

[0033] The re-wet adhesive layer (I) may further contain fatty acids having 12 to 22 carbon atoms and / or fatty acids thereof. Examples of fatty acids having 12 to 22 carbon atoms and fatty acid salts thereof include stearic acid, calcium stearate, sodium stearate, palmitic acid, lauric acid, myristic acid, linoleic acid, and behenic acid. .. Of these, stearic acid, calcium stearate, and sodium stearate are preferable from the viewpoint of processability. Fatty acids having 12 to 22 carbon atoms and their fatty acid salts can be used alone or in combination of two or more.

[0034] If the re-wet adhesive layer (I) contains fatty acids having 12 to 22 carbon atoms and / or their aliphatic salts, the content in the re-wet adhesive layer (I) is , Preferably at 0.01 to 3% by mass, more preferably 0.03 to 2% by mass, and even more preferably 0.1 to 1% by mass, based on the mass of the re-wet adhesive layer (I). is there. If the content of the fatty acid having 12 to 22 carbon atoms and / or the fatty acid salt thereof is in the above range, it tends to be advantageous in terms of processability.

[0035] The re-wet adhesive layer (I) may further contain clay. Clays include synthetic or natural layered silicate clays such as montmorillonite, bentonite, biderite, mica, hexrite, savonite, nontronite, soconite, vermiculite, lady kite, magadite. , Kenya Silicate, Steven Site, Vorcon Silicate, etc. Clay can be used alone or in combination of two or more.

[0036] When the re-wet adhesive layer (I) contains clay, the content in the re-wet adhesive layer (I) is preferably 〇 with respect to the mass of the re-wet adhesive layer (I). .1 to 5% by mass, more preferably 0.1 to 3% by mass, and even more preferably 0.5 to 2% by mass. When the clay content is in the above range, it tends to be advantageous in terms of transparency and strength. 〇 2021/070096 卩 (: 17132020/059444

There are 11.

[0037] The rewet adhesive layer (I) may further contain a plasticizer. When a plasticizer is contained, it is easy to improve the film forming property and coatability when forming the re-wet adhesive layer (I), and as a result, the layer having high adhesive strength in gas barrier property, re-wet adhesive property and low humidity environment. It is preferable because it tends to be. Plasticizers include, for example, water, sorbitol, glycerol, maltitol, xylitol, mannitol, glycerol trioleate, epoxidized flaxseed oil, epoxidized soybean oil, tributyl citrate, acetyltriethyl citrate, glyceryl triacetate, 2 , 2, 4-Urimethyl-1, 3, 3 — Pentandiol diisoptylate, polyethylene oxide, polyethylene glycol. Plasticizers can be used alone or in combination of two or more. Among these plasticizers, water is preferable from the viewpoint of gas barrier property, re-wet adhesive property, and easy to form a layer having high adhesive strength in a low humidity environment.

[0038] The water content (moisture content) in the re-wet adhesive layer (I) is preferably 3 to 20% by mass, more preferably 4-1 to the mass of the re-wet adhesive layer (I). It is 8% by mass, more preferably 7 to 15% by mass. When the water content is in the above range, it is advantageous in terms of gas barrier property, re-wet adhesive property, and adhesive strength in a low humidity environment. The water content is, for example, when the temperature is ^{adjusted at 23 °} 〇 relative humidity of 50% for 2 weeks and then measured at a ^{temperature of 130 ° ◦ using a heat-drying moisture content meter for 30 minutes.} The amount of water.

[0039] The re-wet adhesive layer (I) is a filler, processing stabilizer, weathering stabilizer, colorant, UV absorber, light stabilizer, antioxidant, antistatic agent, difficult, if necessary. Fuels, other thermoplastics, lubricants, fragrances, defoamers, deodorants, bulking agents, release agents, mold release agents, reinforcing agents, cross-linking agents, fungicides, preservatives, crystallization rate retarders, etc. Additives can be further included.

[0040] The form of the re-wet adhesive layer (I) is preferably in the form of a film or a sheet. The thickness of the re-wet adhesive layer (I) is preferably 0.001 or more from the viewpoints of re-wet adhesiveness, adhesive strength in a low humidity environment, gas barrier property, biodegradability, and the like. 〇 2021/070096 卩 (: 17132020/059444

12 More preferably 0.1 or more, further preferably 0.5 or more, particularly preferably 1 or more, preferably 100 or less, more preferably 100 or less, still more preferably 50 or less, Particularly preferably, it is 10 or less. Further, the re-wet adhesive layer (I) may be provided by one or two or more, and may be a single layer or a multi-layer. When there are two or more re-wet adhesive layers (I), the thickness and composition of each layer may be different or the same.

[0041] <Base material layer (II)> The base material layer (II) is not particularly limited, and examples thereof include paper and resin films. The paper is not particularly limited, and examples thereof include kraft paper, high-quality paper, imitation paper, glassin paper, parchment paper, synthetic paper, white paperboard, Manila ball, milk power-ton base paper, cup base paper, ivory paper, and silver paper. Among these, kraft paper, glassin paper, etc. can be preferably used from the viewpoint of easily improving the adhesion to the re-wet adhesive layer (I). The resin film is not particularly limited, for example, polyethylene terephthalate (Micho) film, polypropylene (Mi) film, polyethylene (Mi) film (preferably low density polyethylene (! _ 0 Mi) film). And polylactic acid film, etc. Among these, the Micho film can be preferably used from the viewpoint of easily improving the adhesion with the re-wet adhesive layer (I). The base material layer (II) is more preferably paper from the viewpoint of easily improving the adhesion and biodegradability with the re-wet adhesive layer (I), and from the viewpoint of strength, kraft paper, cardboard and glassine paper. Is even more preferred.

[0042] The thickness of the base material layer (II) is not particularly limited, and is preferably 1 to 100, more preferably 1 to 500, still more preferably 5 to 300, and particularly preferably. It is 1 〇 to 1 5 0 〇 1. The base material layer (II) may be provided with one or more, and may be a single layer or multiple layers. When the base material layer (II) is two or more layers, the thickness and material of each layer may be different or the same.

[0043] The laminate of the present invention includes the re-wet adhesive layer (I) and the base material layer (II). Therefore, it has both high biodegradability and excellent adhesive strength after exposure to a low humidity environment. 〇 2021/070096 卩 (: 17132020/059444

13 Can stand. Moreover, the laminate of the present invention can also have excellent gas barrier properties. The laminate of the present invention is partially or wholly re-moistened (for example, water is partially or wholly applied) to the re-wet adhesive layer (I) in the re-wet part (water-applied part). Adhesive function can be exhibited. Furthermore, even when exposed to a low humidity environment, it is possible to suppress the decrease in adhesive strength and maintain excellent adhesive strength. Therefore, for example, when the laminated body is in the form of a film or a sheet, various forms of packaging material or the like can be formed, or a label, seal or lid material or the like can be formed. Therefore, the laminate of the present invention is particularly useful as a packaging material for foods, a packaging auxiliary material, and the like.

[0044] The laminate of the present invention may include one or more adhesive layers (X) other than the re-wet adhesive layer (I) and the base material layer (II). Examples of the adhesive constituting the adhesive layer (X) include acrylic adhesive, urethane adhesive, epoxy adhesive, vinyl acetate adhesive, ethylene-vinyl acetate adhesive, vinyl chloride adhesive, and silicone adhesive. Examples thereof include adhesives, ditryl cellulose-based adhesives, phenol-based adhesives, polyvinyl alcohol-based adhesives, melamine-based adhesives, and styrene-based adhesives. From the viewpoint of adhesiveness, urethane-based adhesives and the like are preferable. The thickness of the adhesive layer (X) is preferably 0.1 to 100, more preferably 1 to 5 111.

[0045] In one embodiment of the present invention, when the laminate of the present invention has an adhesive layer (X), the adhesive layer (X) is a re-wet adhesive layer (I) and a base material layer (II). It is preferable that it is placed between them. In a preferred embodiment of the present invention, the laminate is a re-wet adhesive layer (I).

, Adhesive layer (X) and substrate layer (II) in this order, or re-wet adhesive layer (I) and substrate layer (II) adjacent to each other. FIG. 1 shows a layered body according to a preferred embodiment of the present invention, that is, a laminated body in which a re-wet adhesive layer (I) 3, an adhesive layer (X) 5 and a base material layer (II) 4 are laminated in this order. 2 is shown.

[0046] The laminate of the present invention is excellent in gas barrier property, particularly oxygen barrier property. Of the laminated body of this Ming dynasty

2 0 / 〇 1 ² .da y. 3 1: 〇〇 is preferably 8.0 or less, more preferably 5.0 or less. 〇 2021/070096 卩 (: 17132020/059444

14

, More preferably 4.0 or less, even more preferably 3.0 or less, particularly preferably 2.0 or less, and most preferably 1.0 or less. When the acid permeability of the laminate is not more than the above upper limit, excellent oxygen barrier properties can be exhibited. Also, the oxygen permeability

20 / 〇! ² · 6 a V. 81: 111) is usually 0.1 or higher. The oxygen permeability of the laminate ^{can be measured by the oxygen permeability measuring device after storing at 23 °} 〇 · 50% [¾1 ^to 1 for 2 weeks and adjusting the humidity, for example, by the method described in Examples. ..

The laminate of the present invention exhibits excellent adhesive strength (adhesiveness) when the re-wet adhesive layer (I) is adhered by re-wet adhesion, and is sufficient even when exposed to a low humidity environment. Can have a strong adhesive strength. The sealing strength after the adhesive obtained by re-wet-bonding the laminate of the present invention is ^{stored in a low humidity environment of 23 ° 〇 20% [¾ 1 to} 1 for 3 days and humidity-controlled is preferable.

Above, more preferably 81 \ 1/15 or more, even more preferably

For the seal strength, after creating an adhesive made by re-wet-bonding the laminates, preferably two identical laminates are prepared, and water is applied to the re-wet adhesive layer (I) of the _ side laminate. After that, the water-applied portion and the re-wet adhesive layer (I) of the other laminated body are overlapped and press-bonded to prepare an adhesive, and then the adhesive is 23 ^° 〇 · 2

The delamination strength measured using a tensile tester under the conditions of a speed of 50 / min, an initial chuck distance of 50, and a peeling angle of 180 ° after storage for 3 days and humidity control. It can be measured by the method described in the example.

[0048] [Method for producing a laminate] The method for producing a laminate of the present invention is not particularly limited, but for example, the re-wet adhesive layer (I) obtained after producing the re-wet adhesive layer (I) is produced. A method of forming an adhesive layer (X) on the adhesive layer (X) and forming a base material layer (II) on the adhesive layer (X) can be mentioned.

The re-wet adhesive layer (I) is, for example, the step of mixing at least the modified starch (8) and the water-soluble polymer _ (mi) to obtain a mixture (1), and the process of extruding the mixture (1). 2), and can be produced by a method that includes the steps of cooling and drying the extruded mixture (3). 〇 2021/070096 卩 (: 17132020/059444

15

[0050] Step (1) is a step of mixing at least the modified starch (8) and the water-soluble polymer (Mimi), and optionally other components, for example, the fatty acid having 12 to 22 carbon atoms and /. Alternatively, the fatty acid salt thereof, the clay, the plasticizer, and the additive can be mixed together.

Step (1) is usually carried out using an extruder. In the extruder, shear stress is applied to each component by screw, and the mixture is homogeneously mixed while being heated by applying external heat to the barrel.

[0052] As the extruder, for example, a twin-screw extruder can be used. The twin screw extruder may be co-rotated or reverse-rotated. The screen diameter is, for example, 20 to 150.

Extruder length (1_) and screw diameter

Ratio of (0)! The --/ 0 ratio may be, for example, 20 to 50. The rotation speed of the screw is preferably 80 "or more, more preferably 100" or more, and the extrusion molding pressure is preferably 5 bar (○.

a) Above, more preferably 10 bar (1.

That is all. Each component can be introduced directly into the extruder. Further, each of these components may be premixed using a mixer and introduced into the extruder.

[0053] In the step (1), from the viewpoint of film formation property and gas barrier property of the mixture, the lower limit is preferably 0.1% by mass or more, more preferably 1% by mass or more, and further preferably 1% by mass or more, based on the mass of the mixture. 10% by mass or more, particularly preferably 15% by mass or more, most preferably 20% by mass or more, preferably 50% by mass or less as the upper limit, more preferably 45% by mass or less, still more preferably 40% by mass. It is preferable to mix the following plasticizers. A preferred plasticizer is water. Here, the mass of the mixture indicates the total mass of the mixture containing the plasticizer. In step (1), the plasticizer may be introduced in the initial stage of extrusion, or the plasticizer may be introduced before reaching the temperature at which the cooking treatment described later is performed, for example, at 100 ^° 0 or less. .. The modified starch () can be made into a gelatin (gel) by being cooked by a combination of moisture, heat and shear stress. In addition, by introducing a separate plasticizer, preferably water, a water-soluble polymer (Snake) \\ 0 2021/070096 卩 (: 17162020/059444)

16

) Can be dissolved, the mixture can be softened, and the modulus and brittleness can be reduced.

[0054] In the step (1), the cooking process is carried out by heating to a temperature preferably more than 100 ° 〇 and 150 ° 〇 or less, and more preferably 115 ° 〇 or more and 140 ° 〇 or less. Here, the cooking treatment is a treatment in which starch granules are crushed and gelled. Heating can be performed by applying heat to the barrel of the extruder from the outside. By applying a stepwise temperature to each barrel, it can be heated to the desired temperature. When ^{cooking is performed at a temperature exceeding 120 °} 〇, it is advantageous in terms of workability.

[0055] The cooked mixture is pushed towards the die, preferably to a temperature of 85 to 120 ° 〇, more preferably 90 to 110 ° 〇 to prevent foaming. Is good. In addition, by exhausting from the barrel, foaming can be prevented and water can be removed.

The residence time in the extruder can be set according to the temperature profile and screw speed, preferably 1 to 2.5 minutes.

In the step (2) of extruding the mixture, the molten mixture that has been pushed through the extruder while being melt-kneaded is extruded from the die. The temperature of the die is preferably 85 to 120 ° 〇, more preferably 90 to 110 ° 〇.

[0058] In the step (3) of cooling and drying the extruded mixture, the rewet adhesive layer (I) can be formed by extruding the mixture into a film or sheet. The extruded mixture is usually a melt.

[0059] When extruding the mixture into a film, the mixture can be extruded from a film forming die and then cooled and dried while being removed by a take-out holer. It is preferable to cool between the die and the mouth roller to prevent the mixture from adhering to the mouth roller. For drying, the mouthpiece may be warmed or dehumidified air may be supplied during dehumidification. Dehumidified air can be used to inflate the film as the film exits the die in the case of the blow tube method. Talc can also be included in the air stream to prevent film blocking. 〇 2021/070096 卩 (: 17132020/059444

17

[0060] The method of forming the adhesive layer (X) on the re-wet adhesive layer (I) is not particularly limited, but for example, the adhesive layer (X) is formed on the re-wet adhesive layer (I). There is a method of applying an adhesive to be applied and drying it.

[0061] The method for forming the base material layer (II) on the adhesive layer (X) is not particularly limited, but for example, after laminating the base material layer (II) on the adhesive layer (X), laminating or the like. There is a method of applying. The laminate of the present invention may be produced by extruding the mixture onto the base material layer (II) using the above-mentioned extruder. Further, it may be manufactured by a sand laminating method in which the adhesive layer (X) is extruded between the re-wet adhesive layer (丨) and the base material layer (丨丨).

[0062] [Multi-layer laminate] The present invention includes the laminate (including the re-wet adhesive layer (I) and the base material layer (II)) and the layer (III), and the re-wet layer of the laminate is included. It includes a multi-layered body having an adhesive layer (I) on the outermost surface. Since the multilayer laminate of the present invention has the re-wet adhesive layer (I) on the outermost surface, it can be partially or wholly adhered to the adherend by re-wetting (for example, application of water).

The layer (III) is not particularly limited as long as it is a layer other than the re-wet adhesive layer (I), the base material layer (II), and the adhesive layer (X), and examples thereof include a protective layer. , Gas barrier layer, moisture-proof layer, light-shielding layer, printing layer, reinforcing layer, etc., which are different from the re-wet adhesive layer (I). As a material for forming the layer (III), such as polyethylene, polypropylene emissions, ethylene - vinyl acetate copolymer, snake ^Rei_1-1, polyvinyl chloride, polyurethane Tan, polyethylene terephthalate, polybutylene terephthalate, polyethylene Chi naphthalate, etc. Polyamides such as polyester and nylon, polyacrylonitrile, cellulose or derivatives thereof, glass, wood and the like can be mentioned. Layer (III) may be provided in one or more layers, and may be a single layer or multiple layers. When layer (III) is two or more layers, the thickness and material of each layer may be different or the same. The layer (III) may be laminated on the re-wet adhesive layer (I) or the base material layer (II) via the adhesive layer (X).

[0064] In the multilayer laminate of the present invention, at least one layer (III) is a re-wet adhesive. 〇 2021/070096 卩 (: 17132020/059444

It is preferably placed on the outermost surface opposite the 18th layer (I). In such an embodiment, by decorating the surface of layer (III) with characters, patterns, etc., labels, stickers, packaging with characters, decorations, etc. can be formed.

The layer structure of the multilayer laminate of the present invention is not particularly limited, but is, for example, a re-wet adhesive layer (I) / adhesive layer (X) / base material layer (II) / adhesive layer (X) / layer. Layer structure having (III) in this order; Re-wet adhesive layer (I) / Base material layer (II) / Adhesive layer (X) / Layer (III) in this order; Re-wet adhesive layer (I) ) / Base material layer (II) / Layer (III) / in this order. The thickness of layer (III) is not particularly limited, but is preferably 1 to 100, more preferably 5 to 500 111.

[0066] [Adhesive, Manufacturing Method and Bag] According to the present invention, the re-wet adhesive layer (I) of the laminated body (including the multi-layered laminated body) and the adherend layer are re-wet-bonded. Including. The adherend layer is a layer selected from the re-wet adhesive layer (I), the base material layer (II) and the layer (III) contained in the laminate or another laminate, or a laminate thereof. Examples include layers contained in adherends other than the body. In other words, the adherend layer is a layer selected from the re-wet adhesive layer (I), the base material layer (II) and the layer (III) contained in the laminate; other laminates that are not the laminate. A layer selected from a re-wet adhesive layer (I), a base material layer (II) and a layer (III) contained in the body; a layer contained in an adherend that is neither the laminate nor the other laminate; Can be mentioned. The present invention also includes a bag made of the adhesive. The other laminated body means the laminated body on the side to be adhered when two or more laminated bodies of the present invention are used.

[0067] The adhesive body of the present invention is a layered product of the present invention in which the re-wet adhesive layer (I) and the adherend layer are re-wet-bonded. Since the adhesive of the present invention can maintain sufficient adhesive strength even when exposed to a low humidity environment, it can exhibit high strength even in such an environment. Furthermore, it is also excellent in biodegradability and gas barrier property.

[0068] Further, the present invention is a method for producing the adhesive, at least re-wetting the laminated body. 〇 2021/070096 卩 (: 17132020/059444

19 The method including a step of re-wetting the adhesive layer (I) and re-wetting the re-wet adhesive layer (I) and the adherend layer is included. In the step, the method for re-wetting the re-wet adhesive layer (I) is not particularly limited, but the method of applying water to the surface of the re-wet adhesive layer (I), the method of spraying water, and the method of re-wetting under high humidity. Among these, the method of applying water is preferable from the viewpoint of easily increasing the adhesive strength of the obtained adhesive. When the adherend layer is a re-wet adhesive layer (I) contained in the same laminate and another laminate, the re-wet adhesive layer (I) on the adherend side may also be re-wetted. The degree of re-humidification can be appropriately adjusted by the amount of water used for re-humidification. The amount of water used is not particularly limited, but for example, 〇. 1 to 100 0 0 ₉ / ^{〇 1 2} is preferable.

It may be. As described above, at least after re-wetting the re-wet adhesive layer (I) of the laminate, the re-wet portion and the adherend layer are brought into contact with each other to obtain the re-wet adhesive layer (I) of the laminate. It can be re-wet-bonded to the adherend layer. Pressure may be applied inward at the same time as or after the contact. It is easy to increase the adhesive strength by applying pressure. The pressure can be adjusted as appropriate according to the type and thickness of the re-wet adhesive layer (I) and the base material layer (II) contained in the laminate, for example, 0.1 to

Preferably 0.

It may be.

[0069] Hereinafter, a specific example of the adhesive (bag) of the present invention will be described. The adhesive (bag) is not limited to the following modes.

[0070] The adhesive shown in Fig. 2 is a two-sided bag consisting of one laminate (film or sheet), which is made _{by bending the laminate 2 3} in two and re-wetting both ends. .. The laminated body 2 3 is a laminated body having the layer structure shown in FIG. As shown in Fig. 2, the adhesive 1 ₃ is on one side when the laminate 2 ₃ is folded in half, and on the side near the corresponding two sides, is the re-wet adhesive layer (I) 3 ₃ side? Water is applied to form the coating part 6 3, and then the laminate 2 3 is folded in half to form the coating part 6 8 and the other re-wet adhesive layer facing the coating part 6 8 (I). It is obtained by re-wet bonding with the bonded part 7 3 in 3 3 (adhesion layer 8 3). Adhesive body 1 3 is attached to the bag because both ends are adhered by the re-wet adhesive part 9 3. 〇 2021/070096 卩 (: 17132020/059444

20 works.

[0071] Incidentally, in FIG. 2, the deposition layer 8 ₃ has shown the embodiment where rewetting adhesive layer (I) contained in the same laminate, coating of rewetting adhesive layer (I) 6 ₃ The formation site may be changed as appropriate to prepare an adhesive (for example, a bag) using the base material layer (II) contained in the same laminate as an adherend layer. Further, in Fig. 2, water is not applied to the bonded portion 73, but water may be applied to the bonded portion 73. Furthermore, by changing the laminated body 2 3 to a multi-layered laminated body and adjusting the formation location of the coating portion as appropriate, the re-wet adhesive layer (I) and the base material layer (II) contained in the same multi-layered laminated body. Alternatively, an adhesive (for example, a bag) may be produced by using the layer (III) as an adherend layer.

[0072] The adhesive (bag) shown in Fig. 3 is a three-sided bag consisting of two laminates (films or sheets), and the two laminates and the vicinity of the three sides of 20 are rehumidified with each other. It is glued. Laminates 2 and 20 are laminates having the layer structure shown in Fig. 1, respectively. As shown in Fig. 3, the adhesive 1 匕 is formed by applying water from the moisturizing adhesive layer (I) 3 13 side to the vicinity of 3 sides of one laminated body 2 匕 to form the coating part 6 13. Then, by superimposing the other laminate 20 from the re-wet adhesive layer (I) 30 side, the re-wet adhesive layer of the coating part 6 and the other laminate 20 facing the coating part 6 ( I) It is obtained by re-wet bonding with the bonded part 70 in 30 (adhesion layer 80). Adhesive body 1 匕 functions as a bag because the vicinity of 3 sides is adhered by 9 匕 of re-wet adhesive part.

Although FIG. 3 shows an embodiment in which the adherend layer 80 is the re-wet adhesive layer (I) contained in the other laminate, the re-wet adhesive layer (I) is applied. An adhesive (for example, a bag) may be prepared by appropriately adjusting the formation portion of the part 6 and using the base material layer (II) contained in the other laminate 20 as an adherend layer. In addition, although water is not applied to the bonded portion 70 in Fig. 3, water may be applied to the bonded portion 70. Furthermore, by changing at least the laminate 20 to a multilayer laminate and adjusting the formation location of the coating portion as appropriate, the re-wet adhesive layer (I) and the base material layer contained in the other multilayer laminate An adhesive (for example, a bag) may be prepared by using (II) or layer (II I) as an adherend layer. 〇 2021/070096 卩 (: 17132020/059444

twenty one

It is also possible to form a laminate using an adherend other than the laminate or the multilayer laminate of the present invention. For example, in the embodiment shown in FIG. 3, the adherend is used instead of one of the laminates. You may use it. The adherend does not have at least the re-wet adhesive layer (I), and may be, for example, a film composed of a base material layer (II) (particularly paper).

[0075] The number of laminates forming the adhesive of the present invention is not particularly limited, and is preferably 1 to 3, more preferably 1 or 2. Further, in the adhesive of the present invention, from the viewpoint of easily increasing the re-wet adhesiveness and the adhesive strength in a low humidity environment, the adherend layer is the re-wet adhesive layer (I) contained in the laminated body or another laminated body. Is preferable. The embodiment shown in Fig. 2 is the re-wet adhesive layer (I) in which the adherend layer is contained in the laminate, and the embodiment shown in Fig. 3 is the re-wet adhesive layer (I) in which the adherend layer is contained in another laminate. Agent layer (I). Although a bag is shown as an example in Fig. 2 and Fig. 3, the mode of the adhesive is not limited to the bag.

[0076] The bag of the present invention is composed of an adhesive formed by re-wet-bonding the re-wet adhesive layer (I) and the adherend layer of the laminated body (for example, FIGS. 2 and 3). In the bag of the present invention, of the total area of the re-wet adhesive layer (I) of the laminated body, the area of re-wet adhesion with the adherend layer is preferably 1 to 90%, more preferably 5 ~ 40%. When the area is within the above range, the volume as a bag can be secured while maintaining the adhesive strength.

The shape of the bag of the present invention is not particularly limited, but for example, a two-way bag (Fig. 2), a three-way bag (Fig. 3), a three-way bag with a chuck, a gassho bag, a gusset bag, a bottom gusset bag, and a star. It may be in the form of an end bag, a stand chuck bag, a two-sided bag, a four-sided flat-bottomed gusset bag, a side seal bag, or a bottom seal bag.

[0078] [Label, Tape and Lid] The present invention includes a label composed of the laminate and having a printed surface on the outermost surface opposite to the re-wet adhesive layer (I) of the laminate. .. The present invention also includes a tape or a lid material made of the laminated body.

[0079] The label of the present invention functions as an adhesive label by re-wet bonding of the re-wet adhesive layer (I). In addition, the decoration such as printed characters and patterns is not particularly limited. 〇 2021/070096 卩 (: 17132020/059444

twenty two

.. The printing method for forming the label of the present invention is not particularly limited, and examples thereof include a screen printing method, a flexographic printing method, and a gravure printing method. Since the label and tape of the present invention have the re-wet adhesive layer (I), they have excellent re-wet adhesive properties.

The application of the lid material of the present invention is not particularly limited, and is suitably used for, for example, a lid material for a container. When used as a lid material for a container, the inside of the container can be sealed by combining with the container body. In particular, the lid material of the present invention is useful as a lid material for food containers because it has excellent gas barrier properties. Further, since the lid material of the present invention is also excellent in biodegradability, the environmental load can be reduced. Example

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these aspects.

[0082] <Test method>

(1) Measurement of oxygen permeability The laminates obtained in Examples and Comparative Examples were stored at 23 ° 050% [¾ !!! For two weeks to adjust the humidity, and then attached to the oxygen permeability measuring device. Oxygen permeability was measured. The measurement conditions were as follows. Equipment: Made by Modern Control Co., Ltd. "1 \ / 1 〇〇〇〇乂 1 chome [¾ 8 2/20 Temperature: 2 3 ° 0 Humidity on oxygen supply side and carrier gas side: 50% [¾ 1 ^~ 1 oxygen Pressure: 1.0 8 1:01 Rear gas pressure: 1.0 8 1:01

[0083] (2) Biodegradability of re-wet adhesive layer (I) Regarding the re-wet adhesive layer (丨) obtained in Examples and Comparative Examples, based on 1 3 0 1 4 8 8 5-1 The following degree of biodegradation was derived from the amount of carbon dioxide generated during biodegradation under aerobic conditions. Biodegradation (%) = (00 ₂ ) 1-(00 ₂ ) 8 /! ^ 〇 Ding (^ 01X44 / 12 X 100) 〇 2021/070096 卩 (: 17132020/059444

twenty three

(00 ₂ ) 1: Cumulative amount discharged from the compost container 〇〇 ₂ Generated amount (9) (00 ₂ ) 8: Cumulative amount discharged from the blank test container <3 〇 ₂ Generated amount (9)

1 ^ 〇 Ding: Amount of dry solids of test material placed in compost container (9)

(^ 〇 Ding: Total organic carbon in the dry solid of the test material (Ding 〇〇 Relative amount (Ding)

9/9)

^{(3) Seal strength under low humidity 23 °} 〇 _ 20% of the adhesive (pressed section) obtained in Examples and Comparative Examples

The test piece was cut out in the shape of a strip of 1 5 1 5 〇 including the adhesive surface of. Delamination strength measurement was performed with a tensile tester (Instron 3367) at a speed of 50 〇! 〇! / Min, an initial chuck distance of 50 〇! 〇 !, and a peeling angle of 1 80 ^°. did. The same test was performed a total of 5 times, and the average value was used as the seal strength value.

[0085] (4) Materials used

<Denatured starch () ñ

--Mr. 〇〇 I

(Registered Trademark): Propylene oxide-modified starch sorghum, amylose content 70% by mass, I

Obtained from 〇 company N 3 II 〇 n 3 I 7 (registered trademark): Cassaba starch modified with propylene oxide, amylose content 20% by mass, I 〇 9 “Obtained from ㊀〇! 丨〇 11 companies

[0086] <Example 1>

(Re-wet adhesive layer) With raw materials

(Registered Trademark) (9.01 <9) and polyvinyl alcohol (solution viscosity)

3. Saponification degree 99%, _{1.01 <9} ) was mixed in an evening mixer for 2 hours, and the obtained mixture was applied to a twin-screw extruder connected to a liquid pump. Figure 4 shows a schematic diagram of the twin-screw extruder used in Example 1, showing the screw diameter of the extruder,! _ / 0 ratio, screw rotation speed, driving method 〇 2021/070096 卩 (: 17132020/059444

Equation 24 and the temperature profile (Table 1) are shown below. [0087] [Table 1] Temperature Profile [in]:

[0088] Screen diameter: 2 7 111 111

! _ / 0] ；匕: 4 8 Screw rotation speed 5 0 0 “〇! Operation method: Co-rotation (engagement self-wiving) method

[0089] When the above mixture was subjected to the twin-screw extruder, it was supplied into the barrel through the weight feeder of the twin-screw extruder and through the hopper at 001 at a speed of 3.5 1 <9 / hour. .. Water was injected into the barrel at a flow rate of 269 / min through a liquid pump (! _) At 0 4. The temperature range of 〇 5 to 〇 9 is the cooking range, and complete gelatinization was completed within these ranges. The pick-up rate was set so that the film extruded from the die would have a thickness of 20 after cooling and drying. In this way, a re-wet adhesive layer (I) was obtained. The water content in the re-wet adhesive layer (I) is 12% by mass with respect to the mass of the re-wet adhesive layer (I). ^{The moisture content is the moisture content measured at a temperature of 230 °} 〇 for 30 minutes using a heat-drying moisture content meter after adjusting the humidity at a temperature of 23 ° 0 and a relative humidity of 50% for 2 weeks. is there.

[0090] (Laminate) An adhesive layer (X) is formed on the obtained re-wet adhesive layer (I) so that the thickness after drying is 30. A laminate was obtained by laminating kraft paper (basis weight 100 0 2 X m ² _s thickness 1 2 0 〇 1) as the material layer (II). The adhesive layer (X) was formed by applying a two-component adhesive using a bar coater and drying it. The two-component adhesive is a two-component reactive polyurethane type consisting of "Takelac (registered trademark) 8_520" manufactured by Mitsui Chemicals, Inc. and "Takenate (registered trademark) 8150" manufactured by Mitsui Chemicals, Inc. It is an adhesive.

[0091] (glue) 〇 2021/070096 卩 (: 17132020/059444

25 Two pieces of the obtained laminate were cut out into 1 500101 X 1 500 101. For the re-wet-bonded surface of one of the two sections

After applying 5 9/〇 1 ² amounts of water to the area of, re-wet adhesive surfaces are overlapped so that the other section and each side overlap, and pressed with a pressure of ^{1 1 <〇 / 〇 2.} And glued to obtain an adhesive. In the obtained adhesive, the adherend layer is the re-wet adhesive layer (I) contained in the other laminated body (one of the two cut outs).

[0092] <Example 2> As a raw material

(Registered Trademark) (4. 001 < ₉ ) and Polyvinyl Alcohol (Solution Viscosity)

3. A re-wet adhesive layer (I), a laminate and an adhering body were obtained in the same manner as in Example 1 except that the saponification degree was 99% and 6.001 < _{9) was used.}

[0093] <Example 3> As a raw material

(Registered Trademark) (9. 801 < ₉ ) and Polyvinyl Alcohol (Solution Viscosity)

3. A re-wet adhesive layer (I), a laminate and an adhering body were obtained in the same manner as in Example 1 except that the saponification degree was 99% and 〇. 201 < _{9) was used.}

[0094] <Example 4> As a raw material

(Registered Trademark) (5. 401 < ₉ ), N 31:

Repeated as in Example 1 except that n 3 I 7 (3.61 <9) and polyvinyl alcohol (solution viscosity 30 ^ 9 a, saponification degree 99%, 1. 00 1 < _{9) were used.} Wet adhesive layer (I), laminate and adhesive were obtained.

[0095] <Example 5> The re-wet adhesive layer is the same as in Example 1 except that ^{glassine paper (7 0 9/01 2} and thickness 70 01) is used as the base material layer (II). (I), a laminate and an adhesive were obtained.

[Example 6> The re-wet adhesive layer (I), as in Example 1, except _{that thick paper (400 9} /〇 ^, thickness 570) was used as the base material layer (II). Obtaining laminates and adhesives 〇 2021/070096 卩 (: 17132020/059444

26.

[Example 7> As the base material layer (II), "Lumirror (registered trademark) 60" (thickness 12000) manufactured by Toray Co., Ltd., which is a stretched polyethylene terephthalate film, was used, except that it was used. The re-wet adhesive layer (I), the laminate and the adhesive were obtained in the same manner as in Example 1.

[0098] <Example 8>

When the two laminates are laminated, the re-wet adhesive surface is the same as in Example 1 except that the re-wet adhesive surface of one laminate and the base material surface of the other laminate are overlapped. Layer (I), laminate and adhesive were obtained. In the obtained adhesive, the adherend layer is the base material layer (II) contained in the other laminated body (one of the two cut outs).

[Example 9> A re-wet adhesive layer (I) and a laminate were obtained in the same manner as in Example 1. The resulting laminate, and glassine paper (7 0 ^9/2, thickness 7 0 01), respectively

1 5 0 out Ri switch for rewetting adhesive surface sections of the laminate, after applying the 1 5 0 01 111 X 5 0 111 region ^5/2 of the amount of water from the end of one side, glassine The re-wet-bonded surface and the glassine paper surface were overlapped so that the slices of the paper overlapped with each side, and pressed with a pressure of 1 to bond them to obtain an adhesive. In the obtained adherend, the adherend layer is a layer contained in the adherend other than the same laminate and other laminates.

[0100] <Example 1 0> Re-wet bonding in the same manner as in Example 9 except ^{that thick paper (4 0 〇 9/01 2 and thickness 570 〇〇) was used instead of glassine paper.} Agent layer (I), laminate and adhesive were obtained. In the obtained adhesive, the adherend layer is a layer contained in the same laminate and adherends other than other laminates.

[0101] <Comparative Example 1> Polyvinyl alcohol (solution viscosity)

3, Saponification degree 99%, 1.0 〇 2021/070096 卩 (: 17132020/059444

27

After dissolving 0 1 <9) in hot water so as to be 10% by weight, put it in a mold on a flat plate to volatilize the water to obtain 20 films, which are used as a re-wet adhesive layer (I). ). A laminate and an adhesive were obtained in the same manner as in Example 1 except that the obtained re-wet adhesive layer (I) was used instead of the re-wet adhesive layer (I) of Example 1. [Comparative Example 2> Re-wet adhesive layer (I), laminate and adhesive in the same manner as in Example 1 except that _{National 7 (10.01 <9) was used as the raw material.} Got

[0103] <Comparative Example 3> As a raw material

A re-wet adhesive layer (I), a laminate, and an adhesive were obtained in the same manner as in Example 1 except that (registered trademark) (10.01 <9) was used.

[0104] <Comparative Example 4> As a raw material

(9.01 <9) and polyvinyl alcohol (solution viscosity)

3, Saponification degree 99%, 1.

A re-wet adhesive layer (I), a laminate, and an adhesive were obtained in the same manner as in Example 1 except that

[0105] Regarding the laminates of Examples 1 to 1 and Comparative Examples 1 to 4, the composition and the acid permeability (| 111_. 20 / 〇! ² · 6 a V. 81: 〇〇 and re-humidity Table 2 shows the results of measuring the biodegradability (%) of the adhesive layer (I). In addition, 20% of the adhesives obtained in Examples 1 to 10 and Comparative Examples 1 to 4 [¾ 1 ^~ Table 2 also shows the results of measuring the seal strength under 1 humidity control and the adherend layer.

[0106] [E _l

* Indicates that the base material layer (11) has broken.

〇 2021/070096 卩 (: 17132020/059444

29

[0107] As shown in Table 2, the laminates obtained in Examples 1 to 10 have a higher degree of biodegradation than Comparative Example 1 and the adhesion obtained as compared with Comparative Examples 2 to 4. It was confirmed that the seal strength was high under low humidity of the body. Therefore, it was confirmed that the laminates obtained in Examples 1 to 10 have high biodegradability and excellent re-wet adhesion even in a low humidity environment. Furthermore, it was confirmed that the laminates obtained in Examples 1 to 10 also had excellent oxygen barrier properties.

[Preparation of Bag> A two-sided bag as shown in Fig. 2 was prepared using the laminate obtained in Example 1. More specifically, the examples

It was squeezed out and bent in the long side direction with the re-wet adhesive layer (I) inside. Then shown in Figure 2.

Overlay the re-wet surfaces so that the other section and each side overlap (so that the coated part 6 3 and the adhered part 7 _{3 overlap), and 1}

A two-sided bag was made by pressing and adhering at a pressure of ^{9/001 2.} It was confirmed that this bag is also highly biodegradable and has excellent re-wet adhesion even under a low humidity environment. Code description

[0109] 1, 1 3, 1 13 Glue

2, 2 〇,, 2 1 〇, 2 〇 Laminated body

3, 3 3, 3 匕, 30 〇 Re-wet adhesive layer (I)

4, 4 3, 4 匕 Base material layer (II)

5 Adhesive layer (X)

6 〇, 6 匕 Application part

7 3, 7 〇 Adhesive part

8 3, 80 〇 Adhesion layer

9 3, 9 Re-wet adhesive part

Claims

\\ 0 2021/070096 卩 (: 17162020/059444 30 Scope of request

[Claim 1] A laminate containing a re-wet adhesive layer (I) and a base material layer (II), and the re-wet adhesive layer (I) is a modified starch () and a water-soluble polymer _ (Amylose). ), And the amylose content of the modified starch () is 45% by mass or more.

[Claim 2] The laminate according to claim 1, wherein the water-soluble polymer _ (Snake) is polyvinyl alcohol.

[Claim 3] Based on a total of 100 parts by mass of the modified starch (8) and the water-soluble polymer _ (Mi), the content of the modified starch () is 40 to 98 parts by mass, and it is water-soluble. The laminate according to claim 1 or 2, wherein the polymer _ (starch) content is 2 to 60 parts by mass.

[Claim 4] The laminate according to any one of claims 1 to 3, wherein the base material layer (II) is paper.

[Claim 5] A multilayer laminate including the laminate and layer (III) according to any one of claims 1 to 4, wherein the re-wet adhesive layer (I) of the laminate is on the outermost surface. Has a multi-layer laminate.

[Claim 6] The re-wet adhesive layer (I) and the adherend layer of the laminate according to any one of claims 1 to 5 are re-wet-bonded, and the adherend layer is. The laminated body or a layer selected from the re-wet adhesive layer (I), the base material layer (II) and the layer (III) contained in the other laminated body, or an adherend other than these laminated bodies. An adhesive that is a layer that is included.

7. The adhesive according to claim 6, wherein the adherend layer is a re-wet adhesive layer (I) contained in the laminate or the other laminate.

[Claim 8] A bag made of the adhesive according to claim 6 or 7.

[Claim 9] The label composed of the laminate according to any one of claims 1 to 5, and the outermost surface of the laminate opposite to the re-wet adhesive layer (I) is printed. , Label.

[Claim 10] A tape comprising the laminate according to any one of claims 1 to 5. 〇 2021/070096 卩 (: 17132020/059444

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[Claim 11] A lid material comprising the laminate according to any one of claims 1 to 5. 12. The method for producing an adhesive according to claim 6, wherein at least the re-wet adhesive layer (I) of the laminate is re-moistened, and the re-wet adhesive layer (I) and the above-mentioned A method that includes the step of re-wetting the adherend.