JP6622495B2 - Laminated sheet and method for producing the laminated sheet - Google Patents

Description

  The present invention relates to a laminated sheet and a method for producing the laminated sheet.

  Conventionally, in order to impart adhesiveness / adhesiveness to foams, adhesive processing suitable for each application, such as laminating adhesive / adhesive layers, applying hot melt adhesives, and impregnating adhesives, etc. Often applied.

  For example, Patent Document 1 proposes an adhesive sheet in which a foam sheet obtained by mechanically stirring an acrylic emulsion is used as a base material and impregnated or laminated with an adhesive.

  However, since open-cell foams consisting only of acrylic emulsions are vulnerable to splitting and easily cause material destruction, Patent Document 2 discloses an acrylic mixture of closed cells and open cells using inorganic and organic foams. A foam sheet obtained by mechanically stirring a system emulsion has been proposed.

  Patent Document 3 proposes an adhesive sheet including an adhesive layer and a slit. In the case of a product with an adhesive, a slit is provided because air enters during construction and air can accumulate, so construction by professional craftsmen is common. This is because the air pocket when pasted on the like can be eliminated.

JP 63-89585 A JP-A-4-45184 JP 2012-126855 A

  However, the conventional foam sheet has at least one of the following problems. First of all, the conventional foam sheet has an increased adhesive force by impregnating an adhesive or providing an adhesive layer for the purpose of enhancing the adhesive strength. There exists a subject that it is not suitable for repeated use, such as causing destruction or decreasing adhesive strength. In addition, it can be applied only to a smooth surface such as glass and cannot be applied to surface-treated glass. In addition, it has a workability that requires high technology when applying a foam sheet to an adherend surface. There was a problem. Furthermore, although the pressure-sensitive adhesive sheet described in Patent Document 3 uses a synthetic resin film, the glass is not stretchable when the glass is stretched by heat. There was a problem that could not.

  Therefore, the present invention can easily eliminate air accumulation, so that it is excellent in workability, has adhesive strength, can be used repeatedly, and is a smooth adherend (for example, a glass surface). An object of the present invention is to provide a method for producing a laminated sheet that can be applied to any adherend (such as a surface-treated glass surface) having unevenness and that can follow the expansion and contraction of the adherend due to heat. And

  As a result of intensive studies to solve the above problems, the present inventors have found that a specific porous foam layer obtained from an acrylic emulsion and an ethylene vinyl acetate copolymer resin emulsion, The present invention has been completed by finding that a laminated sheet capable of achieving the above object is obtained by using a method for producing a laminated sheet having a low stretch ratio layer lower than the stretch ratio of the layer. .

That is, the present invention (1)
A method for producing a laminated sheet comprising: a porous foam layer; and a low stretch ratio layer provided on one surface side of the porous foam layer and having a stretch ratio lower than the stretch ratio of the porous foam layer. ,
The manufacturing method includes a step of foaming an emulsion composition containing an emulsion and a foaming agent using a mechanical floss method to form a foam, and curing the foam.
The emulsion composition comprises an acrylic emulsion, an ethylene vinyl acetate copolymer resin emulsion, and a urethane emulsion of 0 wt% or more and less than 30 wt% based on the total amount of the emulsion,
The porous foam layer is self-adhesive, and is a method for producing a laminated sheet.
The present invention (2)
The method for producing a laminated sheet according to the invention (1), wherein the porous foam layer has a semi-open cell structure.
The present invention (3)
The emulsion composition comprises, based on the total amount of the emulsion, an acrylic emulsion of more than 10% by weight and 90% by weight or less and an ethylene vinyl acetate copolymer resin emulsion of 10% by weight to less than 90% by weight. The method for producing a laminated sheet according to the invention (1) or (2).
The present invention (4)
The emulsion composition further comprises a cross-linking agent;
Any of the inventions (1) to (3), wherein in the step, the foam is cured by applying energy to crosslink the resin constituting the emulsion via the crosslinking agent. It is a manufacturing method of the lamination sheet as described in one.
The present invention (5)
It is a manufacturing method of the lamination sheet as described in any one of invention (1)-(4) in which the said lamination sheet has another layer further in the low expansion-contraction rate layer side of the said porous foam layer.
The present invention (6)
Manufacture of a laminated sheet according to any one of inventions (1) to (5), wherein the low stretch ratio layer or the other layer is a layer having a function as a printed layer, a reflective layer, or a whiteboard. Is the method.
The present invention (7)
It is a method for producing a laminated sheet according to any one of inventions (1) to (6), wherein the laminated sheet is for ceramics, metal, plastic, glass, and surface treatment products thereof.
The present invention (8)
It is a manufacturing method of the lamination sheet as described in any one of invention (1)-(7) which is the object for glass and surface treatment glass, and is for light-shielding.
The present invention (9)
The method for producing a laminated sheet according to any one of inventions (1) to (8), wherein the laminated sheet has heat insulating properties.
The present invention (10)
Acrylic foam obtained using an emulsion;
A laminated sheet comprising a surface layer formed by laminating a film or a nonwoven fabric on the surface,
The emulsion contains an acrylic emulsion and an ethylene vinyl acetate copolymer resin emulsion,
The back side of the acrylic foam has self-adhesiveness,
The surface layer is composed of a layer that does not have elasticity and that can restrain the laminated sheet.
It is a laminated sheet.
The present invention (11)
The emulsion according to the invention (10), which contains 25 to 80% by weight of an acrylic emulsion and 20 to 75% by weight of an ethylene vinyl acetate copolymer resin emulsion based on the total weight of the emulsion. It is a laminated sheet.
The present invention (12)
The laminated sheet according to the invention (10) or (11), further having another layer on the surface layer side of the porous foam.
The present invention (13)
The surface layer or the other layer is a laminated sheet according to any one of inventions (10) to (12), wherein the layer has a function as a printed layer, a reflective layer, or a whiteboard.

Here, in the present invention, “self-adhesive” means that the adhesive adheres to the adherend when pressed because of the nature of the material without applying an adhesive (including providing an adhesive layer) or impregnation. However, when it peels, the property which can be peeled off from a junction part, without transferring to an adherend. In addition, the “semi-open cell structure” is a structure in which the pores (holes) between adjacent bubbles are small compared to the open cells, and unlike the closed cells, the bubbles have small pores and conforms to the JIS L 1096 A method. And a value measured with a Frazier type air permeability tester is 2 [ml / cm ² / s] or more and less than 80 [ml / cm ² / s].

  In the present invention, the “interlaminar peel strength” is an index of the material strength of the sheet according to the present invention, and refers to the stress at the time of tearing when the T-shaped peel is performed. Specifically, the strength can be measured by a test method described later.

  According to the present invention, it is possible to easily eliminate air accumulation, so that it is excellent in workability, has adhesive strength, can be used repeatedly, and is a smooth adherend (for example, a glass surface) or It is possible to provide a method for producing a laminated sheet that can be applied regardless of an adherend with unevenness (for example, a surface-treated glass surface) and can follow expansion and contraction due to heat of the adherend. Become. In addition, the pressure-sensitive adhesive sheet according to the present invention can be applied to various applications (for example, printing media, mirrors, whiteboards) by satisfying the above properties.

It is a conceptual sectional view of a lamination sheet concerning this form. It is a conceptual sectional view of a lamination sheet which has a functional layer concerning this form. It is a cross-sectional SEM photograph of the semi-open cell structure, open cell structure, and closed cell structure of the porous foam based on this form.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, these are merely examples, and the present invention is not limited to the following aspects.

The laminated sheet and the manufacturing method thereof according to this embodiment will be described in the following order.
1 Structure of laminated sheet 2 Manufacturing method of laminated sheet 3 Properties of laminated sheet 4 Use of laminated sheet

[Construction]
FIG. 1 is a conceptual cross-sectional view of a laminated sheet 100. As shown in FIG. 1, a laminated sheet 100 according to this embodiment is a sheet-like laminated body having a porous foam layer 110 and a surface layer 120 provided on one surface side of the porous foam layer 110. is there. Note that the laminated sheet 100 according to the present embodiment only needs to include the porous foam layer 110 and the surface layer 120, and as shown in FIG. 2, other layers (for example, the functional layer 130). The layered structure can be changed as appropriate, for example, with a structure in which the layer is further laminated. The other layers (for example, the functional layer 130) may exist as one or a plurality of layers between the surface layer and the porous foam layer and / or at a position farthest from the porous foam layer. Good. In this embodiment, the surface layer 120 is a low stretch rate layer having a lower stretch rate than the porous foam layer, but the other layers (for example, the functional layer 130) may be low stretch rate layers.

  Hereinafter, the porous foam layer 110 and the surface layer 120 will be described, and then the other layers will be described. In this embodiment, in the laminated structure, the porous foam layer 110 that is in contact with the adherend on the side where the surface layer is provided is the “lower layer” side, and the surface layer 120 that is not in contact with the adherend is the “upper layer”. ”Side.

≪Porous foam layer≫
The porous foam layer 110 according to the present embodiment is a layer provided as a lower layer of the surface layer 120. The material has self-adhesive properties without applying or impregnating the pressure-sensitive adhesive. It functions as a layer that adheres to the surface. In addition, since the porous foam layer 110 in contact with the adherend has a semi-open cell structure, it adheres to the adherend due to the sucker effect. Since the porous foam layer 110 has high stretchability, the porous foam layer 110 can be attached with strong adhesive strength even to an adherend having a surface with unevenness, such as surface-treated glass. However, it is good also as a structure which apply | coats an adhesive as needed.

  Since the porous foam layer 110 has a semi-open cell structure, it is difficult to retain air, and even when it is formed, the air can be easily removed by simply pressing from above.

  Furthermore, when peeling off, since the adhesive is not applied or impregnated, it does not move to the adherend and can be peeled off from the bonded portion, so that it can be used repeatedly. From this, when it is set as the structure which applies an adhesive, it is preferable that there are as few adhesive application parts as possible.

  When the adherend is glass or surface-treated glass, thermal cracking is particularly likely to occur because the glass or surface-treated glass expands and contracts due to heat. Since the porous foam layer 110 has high stretchability, the laminated sheet according to the present invention absorbs the stretch caused by heat of glass or the like, and thus has an effect that thermal cracking is less likely to occur regardless of the material of the surface layer. .

  Here, the porous foam layer 110 according to this embodiment includes an aqueous dispersion (emulsion) containing a water-dispersible resin as a dispersoid and water or a mixture of water and a water-soluble solvent as a dispersion medium, and a foaming agent. An anionic surfactant as an aqueous liquid medium (emulsion composition) is foamed using a mechanical floss method to form a foam, and the foam is cured (the porous material). A specific method for producing the quality foam layer 110 will be described later).

  According to the porous foam layer 110 according to this embodiment, from the material described later, the light blocking property and the UV cut property are exhibited over the entire porous foam layer 110, and the light blocking property and the UV cut property are excellent. Can do. Moreover, by setting it as the structure which does not light-shield completely, if there is sunlight, light can be obtained indoors, without peeling the laminated sheet which concerns on this invention.

  Furthermore, according to the porous foam layer 110 which concerns on this form, heat insulation can be exhibited over the whole porous foam layer 110 from the below-mentioned material, and it can be excellent in heat insulation.

<Thickness>
The thickness of the porous foam layer 110 according to the present embodiment can be appropriately designed according to the application and necessary properties, but is preferably 0.3 mm to 3.0 mm. The reason is that if the thickness is less than 0.3 mm, sufficient light-shielding properties and UV-cutting properties cannot be obtained, and if it is thicker than 3.0 mm, the room becomes dark.

<Density>
The following cell structure can be evaluated by measuring the density of the porous foam layer 110 according to the present embodiment. The higher the density, the smaller the average cell diameter. On the other hand, the lower the density, the more satisfactory the flexibility. Density can be measured by calculating the weight per unit volume. Density [kg / ^{m 3]} is preferably 150~500 [kg / ^{m 3],} more preferably 160~400 [kg / ^{m 3],} at 170~350 [kg / ^{m 3]} More preferably it is. If it is 150 [kg / m ³ ] or more, desired light-shielding properties and heat insulation properties are satisfied, and adhesive strength and delamination strength are sufficient. Moreover, if it is 500 [kg / m < ³ >] or less, it has sufficient softness | flexibility and absorbs the expansion-contraction of glass.

<Cell structure>
The porous foam layer 110 according to this embodiment has a semi-open cell structure. By setting it as such a structure, the adhesion degree can further be provided to the adhesiveness of the raw material which concerns on this invention by the suction cup effect. As a result, it does not have an adhesive layer, has self-adhesiveness, and is less likely to cause air accumulation and can be easily removed even if it occurs.

(Semi-open cell structure)
The semi-open cell structure is a structure in which pores (holes) between adjacent bubbles are smaller than open cells, and unlike the closed cells, the bubbles have small pores. By measuring the air permeability, it is possible to evaluate whether the structure is a semi-open cell structure. As described above, the air permeability measurement method is based on the JIS L 1096 A method, and is measured using a Frazier type air permeability tester. If the air permeability is 2 [ml / cm ² / s] or more and less than 80 [ml / cm ² / s], it can be said that it has a semi-open cell structure. The air permeability is preferably 5 to 70 [ml / cm ² / s], more preferably 10 to 60 [ml / cm ² / s], and 20 to 50 [ml / cm ² / s]. More preferably. Moreover, the confirmation method of a semi-continuous cell structure can be confirmed also with the photograph of a cross section similarly to the calculation method of the following average cell diameter. FIG. 3 shows a cross-sectional SEM photograph. The center is an SEM photograph of a semi-open cell structure according to this embodiment.

  The semi-open cell structure is smaller than the open cell, and the pores (holes) between adjacent bubbles are small. Unlike the closed cell, the bubble has small pores, which is more flexible than the closed cell structure. Even when the material is brought into close contact with the adherend, an air escape path can be created, and the followability can be improved. On the contrary, when compared with a structure having only open cells, the surface in contact with the adherend becomes larger, a strong suction effect can be exhibited, and the adhesive strength is increased.

(Average cell diameter and cell diameter distribution)
The average diameter (average cross-sectional cell diameter) of bubbles in the cross section of the porous foam layer 110 is preferably 200 μm or less, more preferably 150 μm or less, and particularly preferably 100 μm or less. The reason is that the finer the cell diameter, the larger the surface in contact with the adherend, and the stronger suction cup effect can be expected. In addition, as a measuring method of an average cell diameter, the following method shall be followed.

  First, a cross-sectional photograph of the porous foam layer 110 is taken using a scanning electron microscope (SEM, manufactured by Keyence Corporation, VHXD-500). Thereafter, each bubble (cell) diameter is measured using image processing software Image-Pro PLUS (Media Cybernetics, 6.3 ver). More specifically, the contrast is adjusted in order to read an SEM image and recognize bubbles (cells) by contrast. Next, the shape of the foam (cell) is read by image processing (not the perfect circle but the shape is recognized as it is). Next, “diameter (average)” is selected as the measurement item. Next, the diameter passing through the center of gravity of the object is measured in increments of 2 degrees, and each bubble (cell) diameter is calculated as an average value.

(Bubble (cell) diameter distribution)
In the cross-sectional photograph, 70% or more of the bubbles are preferably within ± 50 μm of the average diameter, more preferably within ± 30 μm, and particularly preferably within ± 20 μm. The reason is that when there is no variation, the material breakage (material breakage) does not easily occur at the location of large bubbles, and the delamination strength becomes stronger. Moreover, it is because the adhesive strength by a suction cup effect is obtained stably.

<Material>
The material (material) of the porous foam layer 110 will be described in detail in the manufacturing method described later.

<< Surface >>
As the surface layer (low expansion / contraction layer), a known layer can be used and is not particularly limited. Since the surface layer is provided on one surface side of the porous foam layer, the porous foam layer having self-adhesive properties adheres to the adherend.

  The surface layer 120 has an expansion / contraction rate lower than that of the porous foam layer. By setting it as such a structure, the laminated sheet which concerns on this invention can be affixed on a to-be-adhered body, without wrinkles. In addition, when sticking to adherends that can cause expansion and contraction due to heat such as glass, the porous foam layer absorbs expansion and contraction due to heat such as glass regardless of the expansion rate of the surface layer. Even if it sticks to the member (for example, window glass) which separates, a thermal crack does not arise. In addition, although an expansion / contraction rate is mentioned later in detail, it measures based on JISK6251.

  The surface layer 120 may have a single layer structure or a multilayer structure. The surface layer 120 may have a print layer on which a picture, a pattern, a character, or the like is printed.

<Material>
The material (material) of the surface layer 120 will be described in detail in the manufacturing method described later.

≪Other layers (functional layers) ≫
In addition to the porous foam layer 110 and the surface layer 120, an appropriate layer can be provided as the laminated sheet 100 according to the present embodiment, depending on the purpose, for example, a layer for improving heat insulation and a water retention property. A layer or the like may be provided. In addition, when the expansion / contraction rate of these layers satisfy | fills the said property and it is provided in the one surface side of the porous foam layer, it may serve as a surface layer. Hereinafter, several layers that can be such functional layers will be described as examples.

<Print layer>
The print layer is, for example, printed (for example, a picture, a pattern, etc.) on the front surface, the back surface (for example, when the layer is transparent), the inside (for example, an inner layer composed of multiple layers when the layer is transparent), the whole, etc. , Letters). In this case, in addition to (1) a layer that can be printed as a functional layer, (2) a surface layer (for example, when the functional layer can be seen through in the embodiment of FIG. 1 or the embodiment of FIG. 2), or the porous foam layer 110 (For example, an aspect in which the surface layer can be seen through in FIG. 1) itself may be used as the print layer. Here, when printing on a surface layer or a functional layer, examples of the material include a resin film and a paper material.

<Reflective layer>
The reflective layer is a layer that reflects light (for example, radio waves, infrared rays, visible light, ultraviolet rays, radiation, etc.), sound, and the like. For example, among the reflective layers, the mirror layer is a layer that totally or partially reflects visible light. The said mirror layer is obtained by vapor-depositing and laminating | stacking a vacuum evaporation plating layer, for example on a transparent resin layer, a film, and board (for example, resin mirror layer). The mirror layer functions as a mirror in the case of substantially total reflection, and as a magic mirror in the case of partial reflection (partial transmission). An example of the method for producing the resin mirror layer is a method of generating a silver film by spraying aluminum particles on a PET resin film or the like (vacuum deposition plating). In addition, you may provide the function as said surface printing layer to the said resin mirror layer.

<Whiteboard>
As a functional layer, a layer having a function as a white board can be provided on the porous foam layer 110. Since the porous foam layer 110 is bonded and adhered to the adherend (for example, a glass window or a metal plate), the whiteboard can be attached to the adherend without using a magnet or a fixture. In addition, a well-known thing can be used as a white board.

[Production method]
The laminated sheet 100 according to this embodiment is a laminated body formed by laminating a plurality of layers. Although the manufacturing method (lamination method) of the porous foam layer 110 is not particularly limited, a method of casting and curing the porous foam layer 110 on the surface layer after the surface layer 120 is formed is preferable. Thus, by directly casting the porous foam layer 110 on another layer, the adhesion between the layers can be enhanced without using an adhesive or the like.

  As a manufacturing method (lamination method) of the laminated sheet 100, other layers such as a sheet-like porous foam layer 110, a surface layer 120, and other layers are laminated in a desired order, and they are appropriately bonded with an adhesive or the like. You may make it laminate | stack by making it adhere | attach, unite, etc.

  Moreover, as a manufacturing method (lamination method) of the porous foam layer 110, after forming the porous foam layer 110 first, the dispersion slurry including the surface layer is directly or via another layer of the porous foam layer 110. The surface layer 120 may be formed by coating on the surface.

  Next, after describing in detail about the specific manufacturing method of the porous foam layer 110, the manufacturing method of the surface layer 120 is demonstrated.

≪Method for producing porous foam layer≫
The method for producing the porous foam layer 110 according to the present embodiment includes a step of foaming an emulsion composition containing an emulsion and a foaming agent using a mechanical floss method to form a foam and curing the foam. including. It is preferable that the emulsion composition further contains a crosslinking agent, and in the step, the foam is cured by applying energy to crosslink the resin constituting the emulsion via the crosslinking agent. As a manufacturing method of the porous foam layer 110, a raw material, a composition (blending amount), and a process (specific adjustment step) will be described in detail.

  Furthermore, in the method for producing the porous foam layer 110 according to this embodiment, an amphoteric surfactant may be added in order to retain bubbles. This is because the amphoteric surfactant enters between the anionic surfactants as the foaming agent, which is called a booster effect.

<Raw material>
The porous foam layer 110 according to the present embodiment includes an emulsion, a foaming agent (anionic surfactant) as a raw material, and water, a crosslinking agent and other additives as a dispersion medium (note that it is used in the foaming step). The foaming gas will be described in the foaming process).

(Emulsion)
An emulsion composition that is a raw material of the porous foam layer 110 according to this embodiment includes an acrylic emulsion, an ethylene vinyl acetate copolymer resin emulsion, and a urethane emulsion of 0 wt% or more and less than 30 wt% based on the total amount of the emulsion. And mixed. It is preferable to mix an acrylic emulsion of more than 10% by weight and 90% by weight or less and an ethylene vinyl acetate copolymer resin emulsion of 10% by weight or more and less than 90% by weight, and the total of both emulsions is 70% by weight. It is preferable to mix so that it may exceed%. In addition, the porous foam layer obtained using an emulsion may be called an acrylic foam.

  The emulsion of the present invention uses an acrylic emulsion because it is excellent in adhesive strength, lightness, and heat insulation. Since the acrylic emulsion alone has a low material strength, an ethylene vinyl acetate copolymer resin emulsion is added in order to improve the material strength and further increase the adhesive strength. By doing so, the material strength can be improved and the delamination strength against high adhesive strength can be increased, so that a foam having a semi-open cell structure having a self-adhesive strength that is less likely to cause material destruction is produced. It becomes possible.

  Other examples of the emulsion contained include urethane emulsions, vinyl chloride emulsions, and epoxy emulsions. By using a urethane emulsion, further material strength can be imparted, and this is particularly suitable when the adherend is an adhesive glass or the like. Moreover, the urethane resin foam obtained has excellent flexibility and low compressive residual strain.

・ Acrylic Emulsion Acrylic resin aqueous dispersion (acrylic emulsion) requires a (meth) acrylic acid ester monomer in the presence of a polymerization initiator, and if necessary, an emulsifier and a dispersion stabilizer. The polymerizable monomer component can be obtained by copolymerizing a mixture of other polymerizable monomers copolymerizable with these monomers as necessary.

  Examples of polymerizable monomers that can be used to prepare the acrylic emulsion include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) allylate, (meth ) Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, octadecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, nonyl (meth) acrylate, ( (Meth) acrylic acid such as dodecyl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate Ester monomers; acrylic acid, methacrylic acid, β-carboxyethyl ( Ta) acrylate, 2- (meth) acryloylpropionic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, itaconic acid half ester, maleic acid half ester, maleic anhydride, itaconic anhydride and other unsaturated groups having a carboxyl group Bond-containing monomers: Glycidyl group-containing polymerizable monomers such as glycidyl (meth) acrylate and allyl glycidyl ether; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) Hydroxyl group-containing polymerizable monomers such as acrylate and glycerol mono (meth) acrylate; ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylo Examples thereof include propane propane tri (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, diallyl phthalate, divinylbenzene, and allyl (meth) acrylate.

  In addition, what is necessary is just to use the above-mentioned emulsifier etc., when using an emulsifier at the time of adjustment of acrylic emulsion.

・ Ethylene vinyl acetate copolymer resin emulsion As a manufacturing method of ethylene vinyl acetate copolymer resin emulsion, for example, polyvinyl alcohol or the like is used as a protective colloid, and a cellulose derivative such as hydroxyethyl cellulose or a surfactant is used as an emulsifying dispersant. It can be obtained by copolymerizing ethylene and vinyl acetate monomer by emulsion polymerization.

  The ethylene vinyl acetate copolymer resin emulsion may be obtained by further copolymerizing a vinyl monomer having a functional group such as a carboxyl group, an epoxy group, a sulfonic acid group, a hydroxyl group, a methylol group, or an alkoxy group. Good.

-Urethane emulsion Examples of methods for adjusting the aqueous dispersion of urethane resin (urethane emulsion) include the following methods (I) to (III).
(I) An active hydrogen-containing compound, a compound having a hydrophilic group, and an organic solvent solution or an organic solvent dispersion of a urethane resin having a hydrophilic group obtained by reacting a polyisocyanate are neutralized as necessary. A method of obtaining a urethane resin emulsion by mixing an aqueous solution containing an agent.
(II) Whether an active hydrogen-containing compound, a compound having a hydrophilic group, and a terminal isocyanate group-containing urethane prepolymer having a hydrophilic group obtained by reacting a polyisocyanate are mixed with an aqueous solution containing a neutralizing agent. Alternatively, a method of obtaining a urethane resin emulsion by adding a neutralizing agent to a prepolymer in advance, mixing water and dispersing in water, and then reacting with polyamine.
(III) An active hydrogen-containing compound, a compound having a hydrophilic group, and a terminal isocyanate group-containing urethane prepolymer having a hydrophilic group obtained by reacting a polyisocyanate are mixed with an aqueous solution containing a neutralizing agent and a polyamine. Or a method in which a neutralizing agent is added to the prepolymer in advance and then an aqueous solution containing polyamine is added and mixed to obtain a urethane resin emulsion.

  Examples of the polyisocyanate used in the preparation of the urethane resin include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4. '-Diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 3,3'-dichloro- 4,4′-biphenylene diisocyanate, 1,5-naphthalene diisocyanate, 1,5-tetrahydronaphthalene diisocyanate, tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate Dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenated xylylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 4,4 Examples include '-dicyclohexylmethane diisocyanate and 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate. Moreover, you may use together polyisocyanate more than trivalence in the range which does not impair the effect of invention.

  Examples of the compound having a hydrophilic group include polyester polyols, polyether polyols, polycarbonate polyols, polyacetal polyols, polyacrylate polyols, polyester amide polyols, polythioether polyols, polybutadiene-based polyolefin polyols, and the like. Two or more of these high molecular weight compounds may be used in combination. Known polyester polyols may be used.

  In the above methods (I) to (III), an emulsifier may be further used as long as the effects of the invention are not impaired. Examples of such emulsifiers include nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styrenated phenyl ether, polyoxyethylene sorbitol tetraoleate; fatty acid salts such as sodium oleate, alkyl Anionic emulsifiers such as sulfate esters, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, alkane sulfonate sodium salts, sodium alkyl diphenyl ether sulfonates; polyoxyethylene alkyl sulfates, polyoxyethylene alkylphenyl sulfates Nonionic anionic emulsifiers such as

(Dispersion medium)
In this embodiment, the dispersion medium of the emulsion composition contains water as an essential component, but may be a mixture of water and a water-soluble solvent. Examples of the water-soluble solvent include alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, ethyl carbitol, ethyl cellosolve, and butyl cellosolve, polar solvents such as N-methylpyrrolidone, and the like, one or more of these. A mixture of the above may be used.

(Foaming agent (anionic surfactant))
An anionic surfactant (foaming anionic surfactant) functions as a foaming agent for the emulsion composition.

  Specific examples of anionic surfactants include sodium laurate, sodium myristate, sodium stearate, ammonium stearate, sodium oleate, potassium oleate soap, castor oil potassium soap, palm oil potassium soap, lauroyl sarcosine sodium, Myristoyl sarcosine sodium, oleyl sarcosine sodium, cocoyl sarcosine sodium, palm oil alcohol sodium sulfate, polyoxyethylene sodium lauryl ether sulfate, sodium alkyl sulfosuccinate, sodium lauryl sulfoacetate, sodium alkylbenzene sulfonate, sodium α-olefin sulfonate, etc. Among them, sodium alkylsulfosuccinate is particularly preferable.

  Here, the anionic surfactant used in this embodiment is preferably 10 or more, more preferably 20 or more, in order to facilitate dispersion in the emulsion composition. The above is particularly preferable.

・ HLB
In the present invention, the HLB value means a hydrophilic-hydrophobic balance (HLB) value, and is determined by the Oda method. The method of obtaining HLB by the Oda method is “Introduction to New Surfactants”, pages 195 to 196, published by Sakai Shoten on March 20, 1957, “Synthetics and Applications of Surfactants” 492 It is described on page 502 and can be obtained by HLB = (inorganic / organic) × 10.

(Amphoteric surfactant)
In the porous foam layer 110 according to this embodiment, bubbles are made fine and uniform by using an amphoteric surfactant in addition to the anionic surfactant.

  Especially when an anionic surfactant and an amphoteric surfactant are used in combination, the charge of the hydrophilic group between the molecules of the anionic surfactant is repelled, and the molecules of the anionic surfactant are kept at a certain distance from each other. In addition, since the electrically neutral double-sided surfactant enters between the molecules of the anionic surfactant, the bubbles can be further stabilized and the size of the bubbles can be reduced. For this reason, delamination strength can be improved. Therefore, it is preferable to use an anionic surfactant and an amphoteric surfactant in combination.

  The amphoteric surfactant that can be used in the present invention is not particularly limited, and amphoteric surfactants such as amino acid type, betaine type, and amine oxide type can be used. Betaine-type amphoteric surfactants are preferred because of the higher effects described above. Furthermore, the thing of C10-12 is preferable from the point of the penetration | invasion between the molecules of an anionic surfactant.

  Examples of amino acid type amphoteric surfactants include N-alkyl or alkenyl amino acids or salts thereof. In the N-alkyl or alkenyl amino acid, an alkyl group or an alkenyl group is bonded to a nitrogen atom, and one or two “—R—COOH” (wherein R represents a divalent hydrocarbon group, preferably An alkylene group, particularly preferably having 1 to 2 carbon atoms.). In a compound in which one “—R—COOH” is bonded, a hydrogen atom is further bonded to the nitrogen atom. One “—R—COOH” is called a mono form, and two are called a di form. As the amphoteric surfactant according to the present invention, any of these mono- and di-forms can be used. In the N-alkyl or alkenyl amino acid, the alkyl group and alkenyl group may be linear or branched. Specifically, examples of the amino acid type amphoteric surfactant include sodium lauryldiaminoethylglycine, sodium trimethylglycine, sodium cocoyl taurine, sodium cocoyl methyl taurine, sodium lauroyl glutamate, potassium lauroyl glutamate, lauroyl methyl-β-alanine and the like. It is done.

  Examples of betaine-type amphoteric surfactants include alkyl betaines, imidazolinium betaines, carbobetaines, amide carbobetaines, amide betaines, alkylamide betaines, sulfobetaines, amide sulfobetaines, phosphobetaines, and the like. Specifically, as betaine type amphoteric surfactants, lauryl betaine, stearyl betaine, lauryl dimethylaminoacetic acid betaine, stearyl dimethylaminoacetic acid betaine, lauric acid amidopropyldimethylaminoacetic acid betaine, isostearic acid amidoethyl dimethylaminoacetic acid betaine Isostearic acid amidopropyl dimethylaminoacetic acid betaine, isostearic acid amidoethyl diethylaminoacetic acid betaine, isostearic acid amidopropyl diethylaminoacetic acid betaine, isostearic acid amidoethyl dimethylaminohydroxysulfobetaine, isostearic acid amidopropyl dimethylaminohydroxysulfobetaine, isostearic acid amidoethyl diethylamino Hydroxysulfobetaine, isostearamide Lopyldiethylaminohydroxysulfobetaine, N-lauryl-N, N-dimethylammonium-N-propylsulfobetaine, N-lauryl-N, N-dimethylammonium-N- (2-hydroxypropyl) sulfobetaine, N-lauryl- N, N-dimethyl-N- (2-hydroxy-1-sulfopropyl) ammonium sulfobetaine, lauryl hydroxysulfobetaine, dodecylaminomethyldimethylsulfopropylbetaine, octadecylaminomethyldimethylsulfopropylbetaine, 2-alkyl-N-carboxy Methyl-N-hydroxyethylimidazolinium betaine (2-lauryl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine 2-stearyl-N-carboxymethyl-N-hydroxy Betaine and the like), coconut oil fatty acid amidopropyl betaine, coconut oil fatty acid amide propyl hydroxy sultaine and the like.

  Examples of the amine oxide type amphoteric surfactant include lauryl dimethylamine-N-oxide, oleyldimethylamine-N-oxide, and the like.

  Among the amphoteric surfactants mentioned above, it is preferable to use a betaine-type amphoteric surfactant in the method for producing the porous foam layer 110 according to the present invention, and among the betaine-types, alkylbetaines and imidazolinium betaines are used. Carbobetaine is particularly preferred. Examples of alkylbetaines that can be used in the present invention include stearyl betaine and lauryl betaine. Examples of imidazolinium betaines include 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine. .

(Crosslinking agent (curing agent))
In the method for adjusting the porous foam layer 110 according to this embodiment, the strength is improved by using a crosslinking agent (curing agent).

  Such a crosslinking agent is not particularly limited, and may be added in a necessary amount depending on the application. Examples of the crosslinking method using a crosslinking agent include physical crosslinking, ionic crosslinking, and chemical crosslinking, and the crosslinking method can be selected according to the type of the water-dispersible resin. As the crosslinking agent, a known crosslinking agent can be used, and an epoxy-based crosslinking agent, a melamine-based crosslinking agent, an isocyanate-based crosslinking agent, a carbodiimide-based crosslinking agent, a oxazoline-based crosslinking agent, etc. An appropriate amount can be used according to the type of group and the amount of functional group. In order to improve the adhesive strength, tack strength and delamination strength, an epoxy-based crosslinking agent and an isocyanate-based crosslinking agent are preferable. Of these, aliphatic isocyanates are more preferable. Two or more of these crosslinking agents may be used in combination.

(Other additives)
As other additives, a water dispersible resin dispersing surfactant (emulsifier) or the like may be added.

-Water-dispersible resin-dispersing surfactant The water-dispersible resin-dispersing surfactant according to this embodiment is a surfactant for dispersing a water-dispersible resin (unlike an anionic surfactant, It may not have an effect as a foaming agent). Such a surfactant may be appropriately selected according to the water-dispersible resin to be selected.

<Composition>
(Blending amount and blending ratio of each raw material)
As a compounding quantity of water-dispersible resin (solid content) with respect to a liquid medium, 30-80 weight part is preferable with respect to 100 weight part of liquid media. By setting it as such a range, the effect that a stable foam can be shape | molded is acquired.

-Compounding ratio in emulsion composition About the compounding quantity in an emulsion composition, it is preferable to contain acrylic emulsion of more than 10 weight% and 90 weight% or less on the basis of the whole quantity of an emulsion. It is more preferably 20% by weight or more and 80% by weight or less, and further preferably 30% by weight or more and 75% by weight or less.

  Furthermore, it is preferable to contain 10% by weight or more and less than 90% by weight of ethylene vinyl acetate copolymer resin emulsion based on the total amount of the emulsion. It is more preferably 20% by weight or more and 80% by weight or less, and further preferably 25% by weight or more and 75% by weight or less. This is because if it is 90% by weight or more, it becomes difficult to produce a foam by the mechanical floss method, and the flexibility, adhesive strength, and tack strength are lost.

  Moreover, it is preferable that the acrylic emulsion and the ethylene vinyl acetate copolymer resin emulsion are contained in a total amount exceeding 70% by weight based on the total amount of the emulsion. It is more preferable to contain 80% by weight or more.

  As a compounding quantity of a urethane emulsion, you may contain 0 to 30 weight% urethane emulsion on the basis of the whole quantity of an emulsion. Furthermore, it is preferable that it is 20 weight% or less. This is because, within this range, the material strength can be increased, flexibility can be imparted, and the adhesive strength can satisfy desired properties.

  The compounding amount of the anionic surfactant is preferably 1.0 to 10 parts by weight, more preferably 3 to 10 parts by weight, with the total amount of the emulsion as 100 parts by weight in the emulsion composition. By setting it as such a range, it is easy to make it suitable foaming, and the effect that a fine cell structure can be shape | molded is acquired.

  The compounding amount of the amphoteric surfactant is preferably 0.5 to 10 parts by weight, more preferably 1 to 5 parts by weight, with the total amount of the emulsion as 100 parts by weight in the emulsion composition. By setting it as such a range, it is easy to make it suitable foaming, and the effect that a fine cell structure can be shape | molded is acquired.

  The blending amount of the crosslinking agent (curing agent) is preferably 0.1 to 20 parts by weight, and more preferably 1 to 10 parts by weight based on 100 parts by weight of the total amount of the emulsion in the emulsion composition. By setting it as such a range, the effect that a foam with a small compression residual strain can be shape | molded is acquired.

<Manufacturing method>
The method for producing the porous foam layer 110 according to the present embodiment is to form a foam by foaming an emulsion composition containing a raw material preparation step and an emulsion and a foaming agent using a mechanical floss method, And a step of curing the body (foaming / curing step). The emulsion composition may further contain a crosslinking agent, and in the step, the foam may be cured by applying energy to crosslink the resin constituting the emulsion via the crosslinking agent. Hereinafter, each step will be described in detail.

(Raw material preparation process)
In the raw material preparation step, an emulsion composition that is a raw material mixture of the porous foam layer 110 is prepared by mixing the respective raw materials as described above. The mixing method at this time is not particularly limited, and for example, mixing may be performed while stirring in a container such as a mixing tank for mixing the components.

(Foaming / curing process)
In the foaming / curing step, a predetermined foaming gas is added to the emulsion composition obtained in the raw material preparation step, and these are sufficiently mixed so that many bubbles are present in the emulsion composition (foamed emulsion composition ). This foaming / curing step is usually carried out by sufficiently mixing the raw material mixture of the liquid porous foam obtained in the raw material preparation step and the foaming gas with a mixing device such as a mixing head.

-Foaming gas The foaming gas mixed into the emulsion composition in the stirring / foaming step forms bubbles (cells) in the porous foam layer 110, and is obtained depending on the amount of the foaming gas mixed therein. The expansion ratio and density of the porous foam layer 110 are determined. In order to adjust the density of the porous foam, it is necessary from the density of the desired porous foam and the volume of the raw material of the porous foam (for example, the inner volume of the mold into which the raw material of the porous foam is injected) It is only necessary to calculate the weight of the raw material of the porous foam and determine the amount of the foaming gas so that the desired volume is obtained at this weight. As the type of foaming gas, air is mainly used, but in addition, inert gases such as nitrogen, carbon dioxide, helium, and argon can also be used.

-Foaming method and foaming conditions As the foaming method used in the method for adjusting the porous foam layer 110 according to the present invention, a mechanical floss (mechanical foaming) method is used. The mechanical flossing method is a method in which air in the atmosphere is mixed into the emulsion composition and foamed by stirring the emulsion composition with a stirring blade or the like. As the stirring device, a stirring device generally used in the mechanical floss method can be used without particular limitation, and for example, a homogenizer, a dissolver, a mechanical floss foaming machine, or the like can be used. According to this mechanical froth method, a porous foam having a density suitable for various applications can be obtained by adjusting the mixing ratio of the emulsion composition and air. Other foaming methods can be used in combination, but when a foaming method using a chemical foaming agent is used in combination, the density of closed cells increases, and the flexibility and stretchability of the porous foam increase. In some cases, the production method according to the present invention is not preferable.

  The mixing time of the emulsion composition and air is not particularly limited, but is usually 1 to 10 minutes, preferably 2 to 6 minutes. The mixing temperature is not particularly limited, but is usually room temperature. Further, the stirring speed in the above mixing is preferably 200 rpm or more in order to make the bubbles fine (more preferably 500 rpm or more), and 2000 rpm or less is preferable (800 rpm or less is preferable) in order to smoothly discharge the foam from the foaming machine. More preferred).

-Foam formation The emulsion composition (foamed emulsion composition) foamed as described above is, for example, a sheet shape that matches the thickness of the desired porous foam by a known means such as a doctor knife or a doctor roll. Formed into a foam.

-Curing As a method for curing the foam, a known method can be used. Although the foam according to the present embodiment can be self-crosslinked, the foam may be cured by applying energy to crosslink the resin constituting the emulsion via a crosslinking agent. Although it does not specifically limit as a process of applying energy, For example, a heating process (thermal crosslinking) is mentioned.

  In the heating step, the dispersion medium in the molded foam emulsion composition is evaporated. The drying method at this time is not particularly limited, and for example, hot air drying or the like may be used. Also, the drying temperature and the drying time are not particularly limited, but may be, for example, about 80 ° C. and about 1 to 3 hours.

  Further, in this heating step, the dispersion medium evaporates from the foamed emulsion composition, but the path when the vapor escapes communicates from the inside to the outside of the porous foam. Therefore, in the porous foam layer 110 according to the present embodiment, the path when the water vapor escapes remains as open cells, so that at least some of the bubbles existing in the porous foam become open cells. Here, when the foaming gas mixed in the stirring / foaming step remains as it is, it becomes closed cells in the obtained porous foam, and the mixed foaming gas escapes the vapor in this step. In the case of continuous communication, open cells are formed in the obtained porous foam. That is, in the present invention, some of the bubbles in the porous foam are open cells, and the remaining bubbles are closed cells, resulting in a semi-open cell structure in which open cells and closed cells are mixed.

  When a crosslinking agent is added, in the heating process, the crosslinking (curing) reaction of the raw material proceeds and is completed. Specifically, the raw materials are cross-linked by the cross-linking agent described above to form a cured porous foam. The heating means in this case is not particularly limited as long as the raw material can be sufficiently heated and the raw material can be crosslinked (cured). For example, a tunnel heating furnace or the like can be used. Also, the heating temperature and the heating time may be any temperature and time that can crosslink (harden) the raw material. .

<< Method for Preparing Surface Layer 120 >>
Next, a method for preparing the surface layer 120 will be described.

  The surface layer 120 is provided on one surface of the porous foam layer, and the expansion / contraction rate is lower than the expansion / contraction rate of the porous foam layer. Although it will not be limited if it satisfies this property, for example, it consists of a film, paper, synthetic paper, cloth, synthetic resin, etc. These may be used alone or in combination. As the surface layer 120, for example, films such as polyester film, polypropylene film, polystyrene film, vinyl chloride film, olefin film, polyimide film, synthetic paper, fine paper, coated paper, art paper, cast coated paper, supercast paper, water resistant Paper, craft paper, recycled paper, impregnated paper, Kent paper, thermal paper, and other papers, and the like. From the manufacturing method described later, a sheet having low stretchability that does not allow the raw material to permeate is preferable.

  Examples of the film material used for the surface layer 120 include a polyethylene film (PE film), a polyvinyl chloride film (PVC film), a polyvinylidene chloride film (PVDC film), a polyvinyl alcohol film (PVA film), and a polypropylene film (PP film). Polyester film, polycarbonate film (PC film), polystyrene film (PS film), polyacrylonitrile film (PAN film) ethylene vinyl acetate copolymer film (EVA film), ethylene-vinyl alcohol copolymer film (EVOH film), Ethylene-methacrylic acid copolymer film (EMAA film), nylon film (NY film, polyamide (PA) film), cellophane, Ionomer film (IO film), and the like. As a film material used for the surface layer 120, various metals and magnetic materials are also applicable. These may be used alone or in combination. The film material is not limited to the above example.

  As the paper material used for the surface layer 120, various types of paper such as high-quality paper, coated paper, foil paper, craft paper, recycled paper, synthetic paper, impregnated paper, kent paper, and thermal paper can be applied. These may be used alone or in combination. The paper material is not limited to the above example.

  Examples of the cloth material used for the surface layer 120 include cotton, gauze, double gauze, organge, and woven fabric. These may be used alone or in combination. The cloth and the material thereof are not limited to the above example.

  Synthetic resins used for the surface layer 120 include phenol resin (PF), epoxy resin (EP), melamine resin (MF), urea resin (urea resin, UF), unsaturated polyester resin (UP), alkyd resin, polyurethane ( PUR), thermosetting polyimide (PI) polyethylene (PE) (including high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE)), polypropylene (PP), polyvinyl chloride (PVC) , Polyvinylidene chloride, polystyrene (PS), polyvinyl acetate (PVAc), Teflon (registered trademark) (polytetrafluoroethylene, PTFE), ABS resin (acrylonitrile butadiene styrene resin), AS resin, acrylic resin (PMMA), polyamide (PA) (including nylon) , Polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), glass fiber reinforced polyethylene terephthalate (GF-PET), cyclic Polyolefin (COP), polyphenylene sulfide (PPS), polysulfone (PSF), polyethersulfone (PES), amorphous polyarylate (PAR), liquid crystal polymer (LCP), polyetheretherketone (PEEK), thermoplastic polyimide (PI), polyamideimide (PAI) and the like. These may be used alone or in combination. The synthetic resin is not limited to the above example.

As the surface layer 120, as described above, a sheet such as a film or a nonwoven fabric can be used as a base material. The basis weight of the nonwoven fabric is, for example, 5 to 100 g / m ² .

[nature]
According to the laminated sheet 100 according to the present embodiment, it is difficult to retain air, and even when it is possible, the air can be easily removed simply by pressing from above. Since this property is based on a semi-open cell structure, it can be evaluated by a breathability test.

  In addition, it can be applied to an adherend having a smooth surface such as ceramic, metal, plastic and glass with strong adhesive strength. Furthermore, it can be affixed to a surface-treated glass having surface irregularities such as frosted glass, frosted glass, and template glass with a strong adhesive force. This property can be evaluated by the adhesive strength.

  Furthermore, when peeling off, since the adhesive is not applied or impregnated, it does not move to the adherend and can be peeled off from the bonded portion, so that it can be used repeatedly. Moreover, when peeled off, the material strength is high, so that it can be used repeatedly. The ability to be used repeatedly can be evaluated by delamination strength.

  During use, as described above, the porous foam layer absorbs expansion and contraction due to heat of glass or the like, so that thermal cracking does not occur even if it is applied indoors.

  Since the laminated sheet 100 according to this embodiment has light shielding properties, it can be suitably used as a light shielding sheet. The light shielding property can be evaluated by the solar transmittance and the ultraviolet absorption rate. Moreover, you may have heat insulation. Thermal insulation can be evaluated by thermal conductivity.

-Breathability Breathability is evaluated by a value measured using a Frazier type breathability tester in accordance with JIS L 1096 A method. If the air permeability is 2 [ml / cm ² / s] or more and less than 80 [ml / cm ² / s], it can be said that it has a semi-open cell structure. It is preferably 5 [ml / cm ² / s] or more and less than 70 [ml / cm ² / s], preferably 10 [ml / cm ² / s] or more and less than 60 [ml / cm ² / s]. More preferably, it is 20 [ml / cm ² / s] or more and less than 50 [ml / cm ² / s].

・ Adhesive strength (90 ° peel strength)
The adhesive strength (90 ° peel strength) is in accordance with JIS Z 0237, punched to 24 mm width x 150 mm, and 30 mm wide x foam with a single-sided adhesive tape on the surface (non-adhesive side) to eliminate the influence of elongation. Affixed to 200 mm glass and reciprocated twice with a 2 kg roller and allowed to stand at room temperature for 24 hours. Then, it evaluates by measuring the test force which pulls up at a speed of 300 mm / min (90 degree peeling) using an autograph, and making it adhesive strength (90 degree peeling strength) (N / 24mm). The adhesive strength is preferably 1.0 N / 24 mm or more, and more preferably 1.5 N / 24 mm or more. When the adhesive strength is less than 1.0 N / 24 mm, there is a problem that the adhesive strength is weak.

・ Delamination strength (material strength)
The delamination strength was measured as an index showing the material strength of the porous foam of the present invention. Specifically, the delamination strength is obtained by punching the foam to 12 mm width × 150 mm, sticking a double-sided tape on both sides of the foam, sticking a 12 mm width × 200 mm backing film (PET film) on both sides, and using a 2 kg roller. The sample is reciprocated once and left in an oven at 85 ° C. for 24 hours. Then, it is allowed to stand at room temperature for 1 hour or longer, and the test force obtained by pulling the backing film at a speed of 1000 mm / min (T-peeling) using an autograph is measured to evaluate the delamination strength (N / 12 mm). The delamination strength is preferably 2.0 N / 12 mm or more, and more preferably 4.0 N / 12 mm or more. When the delamination strength is less than 2.0 N / 12 mm, there is a problem that the film is broken when peeled and cannot be used repeatedly.

-Flexibility According to JIS K 6254, the flexibility is evaluated with a 25% compression load. Measure the stress when crushing a φ50 sample (porous foam layer) at a rate of 1.0 mm / min until it reaches a thickness of 25% of the original thickness of the sample. The 25% compressive load is preferably 0.02 MPa or less, and more preferably 0.01 MPa or less. This is because if the 25% compressive load is 0.02 MPa or less, the adherend will have more sufficient followability even if it has some irregularities or has a large stretchability.

-Stretchability In this form, in order to satisfy the favorable workability at the time of sticking, the stretchability of the low stretch ratio layer (surface layer) needs to be lower than the porous foam layer. The expansion / contraction rate of the porous foam layer is evaluated in accordance with JIS K 6251. Specifically, the tensile strain generated in the test piece by the tensile stress, which is expressed as a ratio to the initial length, is measured. The measured tensile strain of the porous foam layer is preferably 100% or more, and more preferably 300% or more. This is because if it is 100% or more, the expansion and contraction of the adherend can be sufficiently absorbed.

-Light-shielding property Light-shielding property is evaluated by solar radiation transmittance (JIS R3106) and ultraviolet light absorption rate (ISO 9050). The solar transmittance is preferably less than 40%, and more preferably less than 30%. When the solar transmittance is 40% or more, the light shielding property is insufficient. The ultraviolet absorption rate is preferably 80% or more, and more preferably 90% or more. When the ultraviolet absorption rate is less than 80%, the ultraviolet absorption rate is insufficient.

-Thermal insulation Thermal insulation depends on the material and thickness of the porous foam layer. What is necessary is just to change suitably according to the objective of use. Moreover, you may provide the layer for improving heat insulation. The heat insulating property can be evaluated by measuring the thermal conductivity in accordance with JIS A 1412-1. An example of the measuring instrument is a thermal conductivity measuring device (Auto Λ) HC-072 (manufactured by Eihiro Seiki Co., Ltd.).

[Usage]
The laminated sheet 100 according to the present embodiment can be applied to various uses depending on its properties. Examples of such applications include calendars, wallpaper (cross), dirt / scratch prevention covers, photo print media, advertising media (printing), warning boards, panels (those used at exhibitions, etc.), seasonal decorations Products, toys, puzzles, stress relief goods, place mats, elbow pads, mouse pads, magnet replacements, thumbtack replacements, double-sided tape, sticky notes, slippage prevention materials, packing materials, glass cushioning materials (bottles, wine bottles, etc.) ) And a grip buffer. Moreover, since it has light-shielding property, it can be widely used for the purpose of light-shielding a window glass etc. and preventing privacy infringement. Moreover, it can be widely used for purposes such as preventing glass scattering and preventing condensation. Furthermore, as a functional layer, it can be used for a mirror, a magic mirror, etc. by providing a reflective layer, and can also be used for a message board etc. by providing a layer having a function as a white board. Also suitable for materials that can undergo thermal expansion, such as ceramics, metal, plastic, and glass, in environments where temperature changes are repeated (eg, near windows, PC equipment, automobiles, factories). Can be used for

  Furthermore, since it has a heat insulating property, it can be widely used in applications intended for heat insulation. In this case, as described above, the heat insulation can be improved.

  Next, although an example and a comparative example explain the present invention still more concretely, the present invention is not limited at all by these examples.

[material]
≪Porous foam raw material≫
First, in the examples and comparative examples, the following raw materials were used as raw materials for the porous foam.
<Water dispersible resin>
・ Acrylic emulsion 1
Acrylic nitrile, acrylic acid alkyl ester, itaconic acid copolymer, pH 9, solid content 60%
・ Acrylic emulsion 2
Ethyl acrylate, methyl methacrylate copolymer, pH 9, solid content 60%
・ Ethylene vinyl acetate copolymer resin emulsion Ethylene-vinyl acetate copolymer resin emulsion, pH 8.5, solid content 55%
<Foaming agent>
・ Anionic surfactant 1
Sodium alkylsulfosuccinate, pH 9.4, solid content 30%, HLB39.7
・ Anionic surfactant 2
Alkyl betaine, fatty acid alkaminolamide, diethanolamine, anionic surfactant mixed system pH 7, solid content 40%
・ Amphoteric foaming agent 3
Alkyl betaine, pH 10, solid content 40%
<Crosslinking agent>
・ Crosslinking agent 1
Epoxy compound, 6 functional groups
・ Crosslinking agent 2
Hydrophobic HDI isocyanurate, functional group number 3.5

<Porous foam raw material 1>
An acrylic emulsion and an ethylene vinyl acetate copolymer resin emulsion are used as main ingredients, and 3 parts by weight of anionic foaming agent 1, 3 parts by weight of anionic foaming agent 2, 1 part by weight with respect to 50:50 parts by weight of each. Part of the amphoteric foaming agent 3 and 2.5 parts by weight of the crosslinking agent were mixed to obtain a porous foam raw material 1 (corresponding to Example 1).
<Porous foam raw material 2-22>
A foam raw material was prepared in the same manner as the porous foam raw material 1 except that the raw materials were blended in the proportions shown in Tables 1 and 2 (corresponding to Example 2-22).
<Porous foam raw material 23-31>
A foam raw material was prepared in the same manner as the porous foam raw material 1 except that the raw materials were blended in the proportions shown in Table 2 (corresponding to Comparative Example 1-9).

≪Base material≫
The following materials were used as the substrate for supporting the foam.
<Base material>
・ Base material 1
PET film (0.038mm) that has been released

[Formation of laminated sheet]
<< Preparation of Example 1 >>
An inert gas such as air or nitrogen gas is added to the porous foam raw material 1, foamed by a mechanical floss method (foaming conditions of 100 to 1000 rpm), cast on the base material 1, and then heat-treated (an oven or a drying furnace) ) To obtain a laminated sheet according to Example 1.
<< Preparation of Example 2-22 >>
A laminated sheet according to Example 2-22 was obtained in the same manner as in Example 1 except that the porous foam material used was changed to porous foam material 2-22.
<< Comparative Example 1-9 >>
A laminated sheet (light-shielding foam with a front sheet) according to Comparative Example 1-9 was obtained in the same manner as in Example 1 except that the porous foam material used was changed to porous foam material 23-31.

[Evaluation test]
Next, the laminated sheets (Examples 1 to 22 and Comparative Examples 1 to 9) were measured and evaluated. The results are shown in Tables 1-2.
-Appearance The surface of the foam was visually evaluated. The cell state was evaluated from a cross-sectional image of the foam by a scanning electron microscope. If the cell surface is uniform due to no foam breakage or cell coalescence on the foam surface, “○” indicates that the surface is slightly rough, and “△” indicates that the cell is very rough. The case was evaluated as “x” when the cell was not formed (when the cell was not foamed).
-Bubble structure The foam structure was evaluated by measuring air permeability. If it is 2 [ml / cm < ² > / s] or more and 80 [ml / cm < ² > / s], it was set as the semi-open cell structure.
-Thickness Thickness was measured with a thickness gauge.
-Density Measured by calculating the weight per unit volume.
・ Flexibility (25% compression load)
In accordance with JIS K 6254, the flexibility was evaluated with a 25% compression load. Measure the stress when crushing a φ50 sample at a speed of 1.0 mm / min until it reaches a thickness of 25% of the original thickness of the specimen. When the measured stress was 0.01 MPa or less, it was evaluated as “◯”, when it was higher than 0.01 Mpa and 0.02 MPa or less, “Δ”, and when it was higher than 0.02 Mpa, “X” was evaluated.
-Stretchability Stretchability was evaluated according to JIS K 6251. Specifically, the tensile strain generated in the test piece due to the tensile stress, expressed as a ratio to the initial length, was measured. When the measured tensile strain was 300% or more, it was evaluated as “◯”, when it was 100% or more and less than 300%, “Δ”, and when it was less than 100%, it was evaluated as “x”.
・ Adhesive strength (90 ° peel strength)
In accordance with JIS Z 0237, punched out to 24 mm width x 150 mm, stuck foam on 30 mm width x 200 mm glass with a single-sided adhesive tape on the surface (non-adhesive side) to eliminate the influence of elongation. Reciprocate once and let it crimp for 24 hours at room temperature. Thereafter, the test force to pull up at a rate of 300 mm / min (90 ° peeling) is measured using an autograph, and the adhesive strength (90 ° peeling strength) (N / 24 mm) is obtained. “O” when the adhesive strength (90 ° peel strength) is 1.5 N / 24 mm or more, “△” when the adhesive strength (90 ° peel strength) is 1.0 N / 24 mm or more and less than 1.5 N / 24 mm, “Adhesive” When the strength (90 ° peel strength) was less than 1.0 N / 24 mm, it was evaluated as “x”.
・ Delamination strength (material strength)
The foam is punched to 12 mm width x 150 mm, double-sided tape is attached to both sides of the foam, a backing film (PET film) of 12 mm width x 200 mm is pasted on both sides, and it is reciprocated twice with a 2 kg roller and pressed into an 85 ° C furnace. Leave for 24 hours. Thereafter, the test force was measured by allowing the backing film to stand at room temperature for 1 hour or longer and pulling the backing film at a rate of 1000 mm / min (T-peeling) using an autograph, and the delamination strength (N / 12 mm) was obtained. When the delamination strength is 4.0 N / 12 mm or more, “◯”, when the delamination strength is 2.0 N / 12 mm or more and less than 4.0 N / 12 mm, “△”, the delamination strength is less than 2.0 N / 12 mm The case was evaluated as “x”.
-Solar transmittance The solar transmittance was measured with an ultraviolet-visible spectrophotometer. When the solar transmittance was less than 30%, it was evaluated as “◯”, when the solar transmittance was 30% or more and less than 40%, “Δ”, and when the solar transmittance was 40% or more, it was evaluated as “x”.
UV absorption rate The UV transmittance was measured with a UV-visible spectrophotometer. When the ultraviolet absorption rate was 90% or more, “◯” was evaluated, when the ultraviolet absorption rate was 80% or more and less than 90%, “Δ”, and when the ultraviolet absorption rate was less than 80%, “x” was evaluated.

  The heat insulating property was measured according to JIS A 1412-1, and the thermal conductivity was measured using a thermal conductivity measuring device (Auto Λ) HC-072 (manufactured by Eihiro Seiki Co., Ltd.). When Examples 13 and 22 were compared with the existing laminated sheet (Tyvek, manufactured by DuPont), the thermal conductivity of Examples 13 and 22 was lower. It was confirmed that the product has sufficient heat insulating properties.

  As shown in Tables 1 and 2, the Examples are Δ or ○ in the evaluation items of adhesive strength and delamination strength, and achieve the object of the present invention. In addition, it turned out that favorable adhesive strength is exhibited also with respect to ceramics, a metal, a plastic, glass, and these surface treatment goods.

  Moreover, the laminated sheet which provided the resin mirror layer as mentioned above as another layer (functional layer) was prepared so that it might become the outermost layer on the PET film of the laminated sheet of Example 3. Similarly, a laminated sheet provided with a white board was prepared. When the laminated sheet was affixed to a SUS plate and a glass surface, it adhered with a good degree of adhesion, and could be used as a reflecting mirror or a white board, respectively. Further, it was found that the laminated sheet can be used repeatedly without causing material destruction during subsequent peeling.

100 laminated sheet 110 porous foam layer 120 surface layer 130 functional layer

Claims (8)

A laminated sheet having a porous foam layer and a low stretch ratio layer provided on one surface side of the porous foam layer and having a stretch ratio lower than the stretch ratio of the porous foam layer (however, an adherend) Except that the surface that comes into contact with the adhesive is laminated or impregnated with an adhesive.)
The manufacturing method includes a step of foaming an emulsion composition containing an emulsion and a foaming agent using a mechanical floss method to form a foam, and curing the foam.
The emulsion composition comprises an acrylic emulsion, an ethylene vinyl acetate copolymer resin emulsion, and a urethane emulsion of 0 wt% or more and less than 30 wt% based on the total amount of the emulsion,
The porous foam layer is self-adhesive;
The porous foam layer has an air permeability of 2 [ml / cm ² / s] or more and 80 [ml / cm ² / s] measured using a Frazier type air permeability tester in accordance with JIS L 1096 A method. It is less than this, The manufacturing method of a lamination sheet characterized by the above-mentioned.   The emulsion composition comprises, based on the total amount of the emulsion, an acrylic emulsion of more than 10% by weight and 90% by weight or less and an ethylene vinyl acetate copolymer resin emulsion of 10% by weight to less than 90% by weight. The manufacturing method of the lamination sheet of Claim 1 characterized by the above-mentioned. The emulsion composition further comprises a cross-linking agent;
The laminated sheet according to claim 1 or 2, wherein in the step, the foam is cured by applying energy to crosslink the resin constituting the emulsion via the crosslinking agent. Production method.   The manufacturing method of the lamination sheet as described in any one of Claims 1-3 in which the said lamination sheet has another layer further in the said low expansion-contraction rate layer side of the said porous foam layer.   The manufacturing method of the lamination sheet as described in any one of Claims 1-4 whose said low expansion-contraction layer or the said other layer is a layer which has a function as a printing layer, a reflection layer, or a white board.   The method for producing a laminated sheet according to any one of claims 1 to 5, wherein the laminated sheet is for ceramics, metal, plastic, glass, and surface treatment products thereof.   The method for producing a laminated sheet according to any one of claims 1 to 6, wherein the laminated sheet is for glass and surface-treated glass and is for light shielding.   The said laminated sheet has heat insulation, The manufacturing method of the laminated sheet as described in any one of Claims 1-7 characterized by the above-mentioned.