JPH11300902A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent formaldehyde from migrating into a room by laminating a thermoplastic resin layer and an acetoacetyl group-containing ethylene-vinyl acetate copolymer saponified substance layer. SOLUTION: A laminate is obtained by coating a solution of an acetoacetyl group-containing ethylene-vinyl acetate copolymer saponified substance on a thermoplastic resin layer. A vinyl chloride resin, a polyolefin resin, a polyester resin or a polyamide resin is used for the thermoplastic resin. The acetoacetyl group-containing ethylene-vinyl acetate copolymer saponified substance is prepared, for example, by a method of reacting an ethylene-vinyl acetate copolymer saponified substance (EVOH) and a diketene, a method of reacting the EVOH to an ester acetoacetate for exchanging an ester, a method of copolymerizing an ethylene, a vinyl acetate, and a vinyl acetoacetate, or the like. Thereby, formaldehyde generating from an object or a base can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a saponified ethylene-vinyl acetate copolymer containing an acetoacetyl group (hereinafter, referred to as a saponified product).
More specifically, the present invention relates to a laminate using AA EVOH), and more particularly, a laminate that absorbs formaldehyde generated from various base materials, adhesives, etc., and is excellent in prevention of migration of plasticizers and stains, and is particularly useful for wallpaper applications. It is about the body.

[0002]

2. Description of the Related Art Conventionally, vinyl chloride resin sheets and films have been used for decorative sheets for finishing wallpaper and furniture for architectural interiors, agricultural materials, automobile interior materials, daily goods (vinyl matte, Umbrellas, etc.), and is also frequently used for office supplies such as desk mats, file covers, notebook covers, stationery, and the like. However, a large amount of plasticizer is contained in such a vinyl chloride resin, and in order to prevent the plasticizer in the vinyl chloride resin from being adversely affected, wallpaper (EV-2-4) in which EVOH is laminated on the vinyl chloride resin layer is used.
No. 7015) and a polyvinyl chloride film containing a plasticizer in an amount of 25 to 55% by weight.
A laminate in which H is laminated (Japanese Patent Laid-Open No. 60-224542) has been proposed.

[0003]

However, although any of the above laminates (wallpaper) has an effect of preventing contamination and migration of a plasticizer, the effect of reducing formaldehyde, which has been regarded as a very problematic problem in recent years, is not. Did not emit.

[0004] Formaldehyde is also used in large amounts as a raw material for the production of low-molecular-weight synthetic and high-molecular resins, and resins obtained therefrom, such as phenol-formaldehyde resin, melamine-formaldehyde resin, urea-formaldehyde resin, guanamine- Formaldehyde resin is used for adhesive processing, molding processing, paper processing, fiber processing, paint,
It is used in a wide range of applications such as decorative boards, but when producing such a resin or processing the resin, the problem that formaldehyde often escapes into the atmosphere, albeit slightly, causing the problem that an irritating odor drifts, In addition, various processed products obtained using such a resin also tend to generate formaldehyde, which is considered to be a problem.

[0005] Also, wood that does not use an adhesive or the like made of the above-mentioned resin also contains formaldehyde, and it is known that a trace amount of formaldehyde is also emitted into the air from such wood. Formaldehyde is harmful to the human body, and if it is present in the air in an amount of 10 ppm or more, it cannot withstand the irritating odor. Building materials, interior materials, equipment, clothing, automobiles, sanitary materials are closely related to processed products and daily life. In fact, there is a strong demand for a method of reducing formaldehyde generated from miscellaneous goods, foods and the like.

Accordingly, an object of the present invention is to provide a laminate which can efficiently reduce formaldehyde, prevent the transfer of formaldehyde into a room, and is excellent in preventing plasticizer transfer from a vinyl chloride resin film or the like. And

[0007]

The inventors of the present invention have conducted intensive studies in view of such circumstances, and as a result, have found that a laminate comprising a thermoplastic resin (A) layer and an AA-ized EVOH (B) layer is laminated. Found that the above object was met, and completed the present invention. In the present invention, it is preferable to coat the thermoplastic resin (A) layer with the AA-ized EVOH (B) solution to obtain a laminate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The thermoplastic resin (A) used in the present invention includes:
Vinyl chloride resin, polyolefin resin, polyester resin, acrylic resin, polystyrene resin, polyamide resin and the like, among which vinyl chloride resin, polyolefin resin, polyester resin, polyamide resin are preferable, A vinyl chloride resin is particularly preferred for interior materials and agricultural films, and the effects of the present invention can be remarkably obtained.

Examples of the polyolefin resin include high-density polyethylene, medium-density polyethylene, (linear) low-density polyethylene, ultra-low-density polyethylene, vinyl acetate, acrylates or butenes, hexene, 4-methyl-1-pentene. Such as polyethylene copolymerized with α-olefins, polypropylene homopolymer, polypropylene graft copolymerized with ethylene, 4-methyl-1
-Polypropylene copolymerized with α-olefins such as pentene, poly-1-butene, poly-4-methyl-1-pentene and the above-mentioned polyolefins containing unsaturated carboxylic acids and their anhydrides, vinylsilane compounds, epoxy groups Modified polyolefin resin obtained by copolymerizing or graft-polymerizing a compound or the like, such as high-density polyethylene,
Medium density polyethylene, (linear) low density polyethylene,
Polyethylene such as ultra-low density polyethylene, polypropylene homopolymer, polypropylene obtained by graft copolymerization of ethylene, polypropylene such as polypropylene obtained by copolymerizing α-olefins, and ethylene-vinyl acetate copolymer are preferably used.

The method for obtaining the AA-modified EVOH (B) used in the present invention is not particularly limited.
A method of reacting saponified vinyl acetate copolymer (hereinafter abbreviated as EVOH) with diketene, a method of reacting EVOH with acetoacetate to transesterify, a method of copolymerizing ethylene, vinyl acetate and vinyl acetoacetate. It may be manufactured by any method such as a method, but from the point that the manufacturing process is simple and a high quality AA EVOH is obtained,
It is preferably produced by a method of reacting EVOH with diketene. As a method of reacting EVOH and diketene, EVOH and gaseous or liquid diketene may be directly reacted, or an organic acid may be adsorbed and stored in advance in EVOH, and then liquid or gaseous under an inert gas atmosphere. A method of spraying and reacting diketene, or spraying and reacting a mixture of an organic acid and liquid diketene on EVOH, or dropping or adding diketene into a mixed system of an acetate ester solvent, an organic acid, and EVOH is used. Can be

As a reaction apparatus for obtaining the AA-modified EVOH (B), any apparatus capable of being heated and equipped with a stirrer is sufficient. For example, a usual reaction type kneader, a Henschel mixer, a ribbon blender, various other blenders, and a stirring and drying apparatus can be used.

The EVOH further contains a small amount of propylene,
Α-olefins such as isobutene, α-octene, α-dodecene, α-octadecene, unsaturated carboxylic acids or salts thereof, partial alkyl esters, complete alkyl esters, nitriles, amides, anhydrides, unsaturated sulfonic acids or salts thereof, Comonomers such as vinyl silane compounds, vinyl chloride, and styrene may be included. Further, as long as the effects of the present invention are not impaired, "post-modification" such as urethanization, acetalization, and cyanoethylation may be performed.

In the above-mentioned AA-modified EVOH (B), in the present invention, particularly, the ethylene content is 10 to 60 mol%, preferably 20 to 50 mol%, and the saponification degree is 90 mol% or more, preferably 95 mol% or more. Yes, the acetoacetyl group content is preferably 0.5 to 15 mol%, more preferably 3 to 10 mol%. If the ethylene content is less than 10 mol%, the stain resistance becomes insufficient, and if it exceeds 60 mol%, the ability of the plasticizer to prevent migration is reduced. Saponification degree 9
If the amount is less than 0 mol%, the ability to prevent the migration of the plasticizer is reduced. Further, when the acetoacetyl group content is less than 0.5 mol%, the deodorizing ability of formaldehyde becomes insufficient,
If it exceeds 15 mol%, the AA-EVOH is insoluble due to a cross-linking reaction between acetoacetyl groups or the like, and the ability to prevent the transfer of the plasticizer is undesirably reduced.

The degree of saponification (mol%) is determined by ¹ H-NMR.
3.3 to 4.0 pp by measurement (solvent; d ₆ -DMSO)
m integrated intensity α (CH of EVOH), 0.85 ppm integrated intensity β (terminal CH _{3 of} EVOH), 1.98 ppm
Is calculated by the following formula (I) from the integrated intensity γ (CH ₃ of the unsaponified portion of EVOH).

(3 × α-β-γ) × 100 / (3 × α-β) (I) The acetoacetyl group content was determined by ¹ H-NMR (270 MH
z) 2.18 ppm as measured (solvent; d ₆ -DMSO)
And the integrated intensity I _CH3 (CH _{3 of the} acetoacetyl group) of 1.
Integrated intensity I _CH2 (EVOH) in the range of 2 to 1.6 ppm
From CH ₂₎ a, is calculated from the following formula (II).

[Equation 2] 2I _CH3 × 100 / 3I _CH2 ... (II)

The above thermoplastic resin (A) layer and AA-modified EV
The laminate is obtained by laminating the OH (B) layers, but the lamination is not particularly limited, and a lamination method such as solution coating or film lamination (dry lamination) can be mentioned.

In solution coating, AA
In the method of coating the VOH (B) solution (or dispersion) on the thermoplastic resin (A) layer, a solvent used is a mixed solvent of water and alcohol, and the amount of water is 30 to 70% by weight (alcohol). Is 30 to 30% by weight), preferably 40 to 60% by weight (the amount of alcohol is 60 to 40% by weight). If the amount is less than 30% by weight or exceeds 70% by weight, it is difficult to obtain a uniform solution. Becomes opaque, which is not preferable. Also, as the alcohol, methanol,
Ethanol, n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol, iso-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and the like, and n-propyl alcohol and iso-propyl alcohol are preferably used. You.

The concentration of the AA-EVOH (B) in the AA-EVOH (B) solution or dispersion can be applied in any range without particular limitation, but is usually about 0.5 to 25% by weight. Preferably, it is particularly preferably 10 to 20% by weight. For coating, known methods can be adopted, for example, gravure coater, reverse roll coater, doctor knife coater, air knife coater, rotary screen coater, flat screen coater, spray, brush coating, bar coater, comma coater, curtain flow Coaters and the like are preferably used, and a gravure coater or a reverse roll coater is preferably used.

When applying the AA-ized EVOH (B) solution or dispersion, the substrate (thermoplastic resin (A)
An adhesive (anchor coat) layer is provided on the surface of the layer. Examples of such an adhesive include an organic titanium-based adhesive, a two-component reactive polyurethane-based adhesive, and a polyester / isocyanate-based adhesive, and a two-component reactive polyurethane-based adhesive is preferably used. The thickness of the adhesive layer is preferably 0.1 to 3 μm after drying, more preferably 0.5 to 3 μm.
1 μm is preferred.

In the film lamination (dry lamination), after the surface of the thermoplastic resin (A) layer is subjected to the above-mentioned primer treatment as required, an organic titanium-based adhesive, a two-component reactive polyurethane-based adhesive is used. In this case, the AA EVOH (B) film may be stretched or non-stretched. The thickness of the AA-modified EVOH (B) film at this time is preferably 5 to 50 μm, and more preferably 10 to 20 μm. In the present invention, although not particularly limited, the solution coating method is more preferable because of the ease of the manufacturing process.

Thus, the thermoplastic resin (A) layer and the AA compound
Although a laminate of the VOH (B) layer is obtained, the thickness of each layer cannot be unequivocally determined depending on its use or the like, but usually the thermoplastic resin (A) layer has a thickness of 50 to 10000 μm (further 100 μm).
AA-ized EVOH (B) layer is 1 to 50 μm.
μm (more preferably 2 to 10 μm). When using an adhesive between the layers, the thickness of the adhesive layer is 0.1 to
About 10 μm is preferable.

In the present invention, the thermoplastic resin (A) layer /
If the thermoplastic resin (A) layer is a and the AAified EVOH (B) layer is b in addition to the laminate of the AAified EVOH (B) layer, a (polyolefin resin) / b / a (vinyl chloride) Resin), a (polyolefin resin) / b / a (polyolefin resin), b / a (polyolefin resin)
/ A (vinyl chloride resin), b / a (polyester resin) / a (vinyl chloride resin), a (acrylic resin)
/ B / a (vinyl chloride resin) and the like, and in particular, (front side) b / a (vinyl chloride resin)
(Back side), (front side) b / a (polyolefin resin) /
Those having a laminated structure of a (vinyl chloride resin) (back side) are useful for interior materials such as wallpaper and decorative sheets, and the back side of the thermoplastic resin (A) layer of these laminated bodies has paper,
A base material for wallpaper such as Japanese paper, nonwoven fabric, asbestos, paper, glass, fiber, cloth, etc.
It is also possible to laminate by a method such as lamination method,
Also, apply vinyl chloride resin (A) to the paper with a knife coater, roll coater, flat screen coater,
Thereafter, AA-ized EVOH (B) can be laminated.

When such a wallpaper is to be stuck to a wall, a known adhesive such as a commonly used water-based starch paste may be applied to the substrate and pressed against the wall, and the wall paper may be added with a value-added value such as a design. It is also useful to apply embossing to at least one surface of the laminate to form an uneven pattern in order to increase the unevenness. As the uneven pattern, a wood grain conduit pattern, a pattern imitating the surface of a painted plate, an abstract pattern, a stone Eye pattern, cloth pattern, line pattern,
Wood patterns and combinations thereof can be used, and the depth of the concavo-convex pattern formed by such embossing varies depending on the pattern.
The thickness of about 200 μm is preferable because it gives a good three-dimensional effect.

It is also effective to foam a base material such as a vinyl chloride resin in order to impart a design property such as a wallpaper. In this case, the lamination process of the AA EVOH (B) is performed before or after the foaming treatment. However, in the case of solution coating, foaming treatment is preferably performed after laminating AA-EVOH (B), and in the case of melt coating or film laminating method, AA-forming EVOH (B) is laminated after foaming. Is preferred.

As a method of forming a concavo-convex pattern by embossing, a method of embossing using a normal heat embossing machine having a desired concavo-convex pattern or a method of forming a desired concavo-convex pattern on a cooling roll of an extrusion coater or the like. Using the applied embossing roll, the embossing process is performed simultaneously with the formation of the AA-ized EVOH (B) layer, the so-called mechanical embossing method such as the so-called doubling embossing method, or printing of an ink containing a foaming inhibitor or a foaming accelerator, For example, a chemical embossing method for forming an uneven pattern in the foaming step is used.

B / a (vinyl chloride resin), b / a
(Polyolefin resin), b / a (polyolefin resin) / a (polyolefin resin), b / a (polyolefin resin) / a (polyolefin resin) / a
(Polyolefin resin) ..., b / a (vinyl chloride resin) / b, b / a (polyolefin resin) / b,
Those having a laminated structure such as b / a (polyolefin-based resin) / a (polyolefin-based resin)... / b are useful as agricultural films (sheets).

In the present invention, if necessary, polyester resin, polyamide resin, polyolefin resin such as polyethylene and polypropylene, polystyrene, polyvinyl alcohol resin, polyurethane resin, polyvinyl acetate, polyvinyl acetate, etc. Resins such as vinyl chloride, plasticizers (although naturally contained in the soft vinyl chloride resin layer), stabilizers, surfactants, crosslinkable substances (epoxy compounds, polyvalent metals, inorganic or organic Polybasic acids or salts thereof), fillers, coloring agents, reinforcing fibers (glass fibers, carbon fibers, etc.), matting agents (talc, silica-based powders, resin fine powders such as polyethylene, polyurethane)
And the like can be blended within a range that does not impair the effects of the present invention.

In the present invention, the AA-modified EVO is used.
In the H (B) layer, a conventionally known deodorant, for example, phosphoric acid-based glass powder containing at least 2% by weight of phosphorus oxide or silver oxide, alkylenediamine, polyalkylenediamine, ferric chloride,
Chromium chloride, manganese chloride, nickel chloride, copper chloride, iron chloride and the like can be contained. When the phosphoric acid-based glass powder, alkylenediamine and polyalkylenediamine are used in combination with the known deodorants, AA-modified EVOH is used.
It is appropriate to add 0.1 to 20 parts by weight, preferably 0.3 to 15 parts by weight, per 100 parts by weight of (B).

Ferric chloride, chromium chloride, manganese chloride,
When metal ions such as nickel chloride, copper chloride and iron chloride are added, they are added in an amount of 2 to 100 mol%, preferably 5 to 80 mol%, based on the acetoacetyl group (and hydroxyl group) of the AA EVOH (B). Is appropriate. The metal ion forms a chelate with an acetoacetyl group or a hydroxyl group and uniformly disperses, thereby effectively acting on malodors (ammonia, hydrogen sulfide, trimethylamine, etc.) other than aldehyde compounds.

The laminate of the present invention thus obtained can be used as a decorative sheet for finishing wall paper or furniture for office interiors, office supplies such as desk mats, notebooks and files using a cover made of PVC leather, etc. Stationery, automotive interior materials,
It can be used for agricultural materials such as agricultural films, daily goods (vinyl mats, umbrellas, etc.), among others, as described in detail above, interior materials such as wallpaper and decorative sheets, and agricultural films (sheets). It is particularly useful as a wallpaper which is excellent in stain resistance and prevention of migration of a plasticizer, and which has an excellent effect of reducing formaldehyde which has been regarded as a problem in recent years.

[0030]

The present invention will be specifically described below with reference to examples. In the examples, “parts” and “%” mean on a weight basis unless otherwise specified. The following (B-1) to (B-3) were used as saponified ethylene-vinyl acetate copolymers containing an acetoacetyl group. [AA-modified EVOH (B-1)] An acetoacetyl group content of 5 mol%, an ethylene content of 45 mol%, and a saponification degree of 94.
6 mol%, melt index 12 g / 10 min (210
[AA, EVOH (B-2)] acetoacetyl group content: 7 mol%, ethylene content: 35 mol%, saponification degree: 92.degree.
6 mol%, melt index 12 g / 10 min (210
[AA, EVOH (B-3)] acetoacetyl group content 3 mol%, ethylene content 45 mol%, saponification degree 96.
6 mol%, melt index 3 g / 10 min (210
° C, load 2160g)

Example 1 A resin composition comprising 100 parts of a vinyl chloride resin, 90 parts of calcium carbonate, 45 parts of dioctyl phthalate, 5 parts of chlorinated paraffin, 3 parts of a stabilizer, 5 parts of a foaming agent, and 18 parts of titanium oxide was superposed. After uniformly mixing with a mixer, a film having a thickness of 0.15 mm was obtained with a single screw extruder. This is 2
The sheet was foamed in a gear oven at 30 ° C. for 30 seconds to produce a 1 mm thick sheet (expansion ratio: 6.7 times). An isocyanate-reactive polyurethane-based adhesive (AD-335A / cat-1 manufactured by Toyo Morton Co., Ltd.) is provided on one side of the sheet.
0) and dried at 100 ° C. (0.5 μm in thickness after drying). Next, on top of this, AA-ized EVOH
AA EVOH obtained by dissolving (B-1) in a water / alcohol mixed solvent (mixing weight ratio: water / alcohol = 30/70)
(B-1) The solution (concentration: 15%) was applied using a bar coater, and dried at 80 ° C. for 3 minutes with a hot air drier to obtain a laminate having a 5 μm coating layer formed thereon. The following evaluation was performed using the obtained laminated body.

[0032] (formaldehyde absorbing power) to plywood released amount formaldehyde ^{10.0mg / (h · m 2)} , the polyurethane adhesive to the laminate AA-EVOH (B-1) layer surface is on the front side And the amount of formaldehyde released was measured. The formaldehyde content was determined by the chip mode test method (DIN 5236).
It was measured by the formaldehyde measurement method by the gas analysis method of 8).

(Plasticizer Transfer Prevention) The laminate (100
(mm × 100 mm) AA-formed EVOH (B-1) layer surface was brought into contact with a polystyrene disk having a diameter of 50 mm and a thickness of 3 mm, and a load of 10 kg / m ² was applied from above on it.
The amount of transfer of the plasticizer after standing for 10 days at 65 ° C. and 65% RH was measured (weight change). Similarly, at 40 ° C. and 90%
The amount of transfer (weight change) of the plasticizer after standing for 10 days under RH conditions was also measured. The evaluation criteria are as follows.・ ・ ・: Weight change is less than 1 g / m ² ×: Weight change is 1 g / m ² or more

(Contamination removal property) AA-ized EVOH of laminate
(B-1) Hot coffee of about 70 ° C. having a diameter of 2
cm or about 20 cm.
The surface state of the laminate after wiping with bleached cotton moistened with water after standing for a time was visually evaluated as follows. Incidentally, the evaluation was similarly performed for the soft polyvinyl chloride resin sheet single layer. Shoe ink (wiped with a neutral detergent), softening, and water-based magic (wiped with a commercially available detergent (Magic Lin)) were similarly evaluated.・ ・ ・: Completely wiped and no trace of contamination was observed. ×: Traces of contamination are observed.

Example 2 An evaluation was performed in the same manner as in Example 1 except that AA-modified EVOH (B-1) was replaced with AA-modified EVOH (B-2).

Example 3 AA-modified EVOH (B-3) was coated with a single screw extruder to a thickness of 20 μm.
m, and then the film was used in Example 1 and the isocyanate-reactive polyurethane adhesive (AD-335A / cat-1 manufactured by Toyo Morton Co., Ltd.) was used on one side.
0) was dry-laminated on the adhesive surface of a foamed vinyl chloride resin sheet (1 mm thick) coated with 0.5 g / m ² to obtain a laminate. The obtained laminate was evaluated in the same manner as in Example 1.

COMPARATIVE EXAMPLE 1 In Example 1, AA-modified EVOH (B-1) was prepared by adding ethylene content of 45 mol%, saponification degree of 99.6 mol%, melt index (MI) of 12 g / 10 min (load 2160
g) The evaluation was performed in the same manner except that EVOH was replaced. Table 1 shows the results of Examples and Comparative Examples.

[0038]

TABLE 1 release formaldehyde weight plasticizer migration preventive property stain release ^{mg / (h · m 2)} 60% RH 90% RH Example 1 1.2 ○ ○ ○ 〃 2 0.9 ○ ○ ○ 〃 3 3. 0 ○ ○ ○ Comparative Example 1 9.2 × × ×

[0039]

The laminate of the present invention comprises a thermoplastic resin (A).
Since the layer and the AA-ized EVOH (B) layer are laminated, it is very excellent in reducing formaldehyde generated from an object or a substrate containing formaldehyde, and is excellent in prevention of migration of a plasticizer and stain resistance. It shows the effect, such as wall paper for building interior, decorative sheet for finishing furniture etc., office supplies such as desk mats, stationery such as notebooks and files using PVC leather cover, interior materials for automobiles, agriculture It is also very useful for laminated materials such as agricultural materials such as film for daily use and daily goods (vinyl mat, umbrella, etc.).

Claims (5)

[Claims] 1. A thermoplastic resin (A) layer and an acetoacetyl group-containing ethylene-vinyl acetate copolymer saponified product (B)
A laminate comprising a stack of layers. 2. The laminate according to claim 1, wherein a solution of a saponified acetoacetyl group-containing ethylene-vinyl acetate copolymer (B) is coated on the thermoplastic resin (A) layer. 3. The laminate according to claim 1, wherein the thermoplastic resin (A) is any one of a vinyl chloride resin, a polyolefin resin, a polyester resin, and a polyamide resin. 4. The laminate according to claim 1, wherein the laminate is used for interior materials or agricultural films. 5. The laminate according to claim 4, wherein the interior material is used for wallpaper.