JP2021037649A - Molding sheet, molding product, method for protecting or repairing bolt nut, and method for protecting or repairing steel structure - Google Patents

Abstract

To provide a laminated sheet which is excellent in a thermoforming property, an anticorrosion property, antiweatherability, and an antifouling property and in which each layer is bonded by a high adhesive force.SOLUTION: A sheet 100 for thermoforming comprises at least an A layer 110a, a B layer 110b, and a thermoplastic resin layer 130 in this order. In this sheet 100, (E'(140°C)) value/(E'(110°C)) value is 0.1 to 1.0. A layer 110a; a layer consisting of a resin composition containing 50-100 pts.mass of a polyvinylidene fluoride resin and 0-50 pts.mass of a poly(meth)acrylic ester-based resin (when the total of both is 100 pts. mass). B layer 110b; a layer consisting of a resin composition containing 0 to less than 50 pts.mass of a polyvinylidene fluoride resin and greater than 50 pts.mass and less than or equal to 100 pts.mass of a poly(meth)acrylic ester-based resin (when the total of both is 100 pts.mass).SELECTED DRAWING: Figure 1

Description

The present invention relates to a molding sheet. The present invention also relates to a molded product obtained by molding the molding sheet. The present invention also relates to a steel structure provided with the molded product. The present invention also relates to a method for protecting or repairing bolts and nuts using the molded product. The present invention also relates to a method for protecting or repairing a steel structure using the molded product.

In the laminated sheet, there are cases where the same system resin is laminated and cases where different system resins are laminated. In the case of different system resins, these may be directly laminated or an adhesive layer may be interposed between these layers. These techniques include the following (Patent Documents 1 to 11).

Further, a method of using bolts and nuts is known as a method of fastening various structures. Bolts and nuts generally contain iron and / or copper components and have protrusions that project from the surface of the structure when fixed to the structure. In addition, the protrusions have a complex shape. For this reason, there is a problem that it is easily exposed to wind and rain, rainwater that has entered the inside is difficult to escape, and rust is likely to occur. Therefore, there is known a method of protecting bolts and nuts and preventing the occurrence of rust by covering the joints of bolts and nuts with a resin cap (bolt nut cap) (Patent Document 12).

Japanese Unexamined Patent Publication No. 02-194950 Japanese Unexamined Patent Publication No. 05-229066 Japanese Unexamined Patent Publication No. 2006-051678 Japanese Unexamined Patent Publication No. 2013-028065 Japanese Unexamined Patent Publication No. 2016-137612 Japanese Unexamined Patent Publication No. 2016-203436 JP-A-2017-119403 JP-A-2007-045067 International Publication No. 2006/121079 Japanese Unexamined Patent Publication No. 2013-071267 International Publication No. 2016/010013 Japanese Patent No. 6487586

When considering molding a resin laminated sheet to produce a molded product and using the molded product to protect or repair a protruding portion having a complicated shape, it is desirable that the laminated sheet has the following characteristics.
-Each layer that composes the laminated sheet is adhered with high adhesive strength.
-Excellent thermoformability (vacuum formability, compressed air formability).
-Excellent anticorrosion.
-Excellent weather resistance.
-Excellent antifouling property.
However, it is considered that there is not yet a laminated sheet that satisfies these characteristics.

The present invention has been created in view of the above circumstances, and an object of the present invention is to provide a molding sheet having the above characteristics. Another object of the present invention is to provide a molded product obtained by molding the molding sheet. Another object of the present invention is to provide a steel structure provided with the molded product. Another object of the present invention is to provide a method for protecting or repairing bolts and nuts using the molded product. Another object of the present invention is to provide a method for protecting or repairing a steel structure using the molded sheet for molding.

As a result of conducting various studies to achieve the above-mentioned problems, the present inventors have found that the above-mentioned problems can be achieved by using a molding sheet having a specific configuration, and are exemplified below. The present invention has been reached.

[1]
A thermoforming sheet provided with at least the following A layer and B layer and a thermoplastic resin layer in this order, and has a storage elastic modulus (E'(E'(E'(E')" at 140 ° C. obtained by dynamic viscoelasticity measurement of the thermoforming sheet. The value ((140 ° C.) value) divided by the storage elastic modulus (E'(110 ° C.) value) at 110 ° C. ((E'(140 ° C.)) value / (E'(110 ° C.)) value) is 0.1. A thermoforming sheet of ~ 1.0.
Layer A: Resin composition containing 50 parts by mass or more and 100 parts by mass or less of a polyvinylidene fluoride resin and 0 parts by mass or more and 50 parts by mass or less of a poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things.
Layer B: Resin composition containing 0 parts by mass or more and less than 50 parts by mass of polyvinylidene fluoride resin and more than 50 parts by mass and 100 parts by mass or less of poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things.
[2]
The thermoforming sheet according to [1], wherein the resin composition constituting the B layer contains 0.05 to 15 parts by mass of an ultraviolet absorber.
[3]
The thermoforming sheet according to [1] or [2], wherein the total light transmittance measured according to the measuring method specified in JIS K7361-1-1997 is 75% or more.
[4]
The thermoforming sheet according to any one of [1] to [3], wherein the HAZE measured according to the measuring method specified in JIS K7136-2000 is 60% or less.
[5]
The thermoplastic resin layer contains one or more selected from the group consisting of poly (meth) acrylic acid ester-based resin, polyvinyl chloride-based resin, polycarbonate-based resin, polyethylene terephthalate-based resin, and polyamide-based resin. , The thermoplastic sheet according to any one of [1] to [4].
[6]
The thermoforming sheet according to any one of [1] to [5], which has a thickness of 200 to 2,000 μm.
[7]
The thermoforming sheet according to any one of [1] to [6], wherein the total thickness of the A layer and the B layer is 10 to 300 μm, and the thickness of the thermoplastic resin layer is 100 to 1,990 μm.
[8]
A thermoformed product obtained by thermoforming the molding sheet according to any one of [1] to [7].
[9]
The thermoformed product according to [8], which is a bolt / nut cap provided with at least the A layer, the B layer, and the thermoplastic resin layer in this order from the outside to the inside.
[10]
A method for protecting or repairing one or both of bolts and nuts, which comprises fixing the thermoformed product according to [9] so as to cover the protrusions of one or both of the bolts and nuts using an adhesive.
[11]
A method for protecting or repairing a steel structure including a steel material and bolts and nuts fixed to the steel material, using an adhesive to obtain a thermoformed product according to [8] or [9]. A step of fixing to the surface of the steel material so as to cover one or both protrusions of the nut, and
The process of attaching the anticorrosion sheet to the surface of the steel material and
Protection or repair methods including.
[12]
The protection or repair method according to [10] or [11], wherein the adhesive is a colorless and transparent acrylic adhesive.
[13]
A steel structure including the thermoformed product according to [8], a steel material, and bolts and nuts fixed to the steel material, wherein the thermoformed product has protrusions of one or both of the bolts and nuts. A steel structure fixed to the surface of the steel material so as to cover the steel material.
[14]
A steel structure protected or repaired using the protection or repair method described in [11].

The molding sheet according to an embodiment of the present invention has the following characteristics.
-Each layer that makes up the sheet is adhered with high adhesive strength.
-Excellent thermoformability (vacuum formability, compressed air formability).
-Excellent anticorrosion.
-Excellent weather resistance.
-Excellent antifouling property.
Therefore, in the molding sheet according to the embodiment of the present invention, a molded product is produced from the molding sheet by thermoforming, and a protruding portion (eg, a protruding portion locally protruding from the surface of a structure used indoors or outdoors). : By coating the molded product on the protruding parts of bolts and nuts), it can be suitably applied to applications such as protecting or repairing the protruding parts. For example, by covering the protruding parts of bolts and nuts fixed to the steel structure, deterioration of the coated bolts and nuts can be suppressed over a long period of time, so maintenance work for the steel structure can be reduced. Is possible.

Further, the molding sheet according to the embodiment of the present invention has good total light transmittance and / or HAZE, and a protruding portion (eg, bolt and nut) covered with a thermoformed product produced from the molding sheet. ) Is easily visible. Therefore, it is possible to grasp the state of the protruding portion covered with the molded product without peeling off the molded product produced from the molding sheet. For example, when the protruding portions of bolts and nuts fixed to a steel structure are covered with a molded product, deterioration prediction and maintenance work of the steel structure is also facilitated. Further, when the surface of the steel structure is painted, the degree of aging deterioration of the paint and the steel structure can be easily determined from the degree of fading of the paint.

It is a schematic cross-sectional view which shows the laminated structure of the thermoforming sheet which concerns on one Embodiment of this invention. It is a schematic cross-sectional view which shows the laminated structure of the thermoforming sheet which concerns on another Embodiment of this invention. It is a schematic side view of the bolt nut cap which concerns on 1st Embodiment of this invention. It is a schematic side view of the bolt nut cap which concerns on the 2nd Embodiment of this invention. The bolts and nuts of the first and second embodiments of the present invention are used to cover the protruding parts of the bolts and nuts fixed to the steel material, and further, an anticorrosion sheet is attached to the surface of the steel material, and the ends thereof are attached. It is a schematic side sectional view which shows the state after being superposed on the flange part of a bolt nut cap. However, the bolts and nuts are shown in a schematic side view. After the anticorrosion sheet was attached to the surface of the steel material, it was fixed to the steel material by superimposing the flange portion of the bolt nut cap according to the first and second embodiments of the present invention on the end portion of the anticorrosion sheet. It is a schematic side sectional view which shows the state which covered the protruding part of a bolt and a nut. However, the bolts and nuts are shown in a schematic side view. It is a schematic side sectional view of a bolt-nut cap and a steel material when a torusia type high-strength bolt fixed to a steel material is covered with a bolt-nut cap. However, the Torcia type high-strength bolt shows a schematic side view. It is a schematic side sectional view of a bolt nut cap and a steel material when a combination bolt of a hexagon bolt and a hexagon nut fixed to a steel material is covered with a bolt nut cap. However, the combination of the hexagon bolt and the hexagon nut is shown in a schematic side view. The state after covering the protruding parts of the bolts and nuts fixed to the steel material with the bolts and nut caps according to the first and second embodiments of the invention and further attaching the anticorrosion sheet to the edge surface of the steel material surface. It is a schematic side sectional view which shows. However, the bolts and nuts are shown in a schematic side view.

Hereinafter, embodiments of the present invention will be described. The embodiments described below exemplify typical embodiments of the present invention, and are not intended to narrowly interpret the technical scope of the present invention.

<1. Thermoforming sheet>
FIG. 1 shows a schematic cross-sectional view showing a laminated structure of a thermoforming sheet (100) according to an embodiment of the present invention. The thermoforming sheet (100) includes an A layer (110a), a B layer (110b), and a thermoplastic resin layer (130) in this order. The A layer (110a) and the B layer (110b) form a fluorine-based resin layer (110). In the present embodiment, the fluorine-based resin layer (110) and the thermoplastic resin layer (130) are directly bonded to each other without any other resin layer intervening.

FIG. 2 shows a schematic cross-sectional view showing a laminated structure of a thermoforming sheet (100) according to another embodiment of the present invention. The thermoforming sheet (100) includes an A layer (110a), a B layer (110b), an adhesive layer (120), and a thermoplastic resin layer (130) in this order. The thermoforming sheet (100) according to the embodiment shown in FIG. 2 has an adhesive layer (120) interposed between the fluororesin layer (110) and the thermoplastic resin layer (130). , Different from the thermoforming sheet (100) according to the embodiment shown in FIG.

In one embodiment, the thermoforming sheet (100) has a storage elastic modulus (E'(140 ° C.) value of 140 ° C. obtained by dynamic viscoelasticity measurement) and a storage elastic modulus of 110 ° C. (E'(110 ° C.). ) Value) divided by ((E'(140 ° C.)) value / (E'(110 ° C.)) value) is 0.1 to 1.0. When the (E'(140 ° C.)) value / (E'(110 ° C.)) value is in the above range, the thermoforming sheet (100) can obtain high thermoforming property. The (E'(140 ° C.)) value / (E'(110 ° C.)) value is preferably 0.15 to 0.95, more preferably 0.2 to 0.9, and even more preferably 0. It is .25 to 0.75, and particularly preferably 0.3 to 0.50. If the (E'(140 ° C.)) value / (E'(110 ° C.)) value exceeds 1, the plasticization at the temperature rise is insufficient, or the material crystallizes and becomes hard due to the temperature rise. Alternatively, since it is presumed that the material is thermosetting and is not suitable for thermoforming, it does not exceed 1.

The storage elastic modulus can be determined by measuring the dynamic viscoelasticity using a viscoelasticity measuring device RSA-G2 or the like manufactured by TA Instruments. In the present invention, the storage elastic modulus E'of the thermoforming sheet is a tensile mode, a frequency of 1.0 Hz, a heating rate of 4 ° C./min, a measurement temperature range of 30 to 180 ° C., and MD when the measurement direction can be specified. If it cannot be specified, the value obtained from the dynamic viscoelasticity measurement in any direction will be used.

Although it is not intended that the present invention is limited by theory, by setting the (E'(140 ° C.)) value / (E'(110 ° C.)) value in the above range, the thermoforming sheet can be obtained. The reason why high thermoformability can be obtained is presumed as follows. The temperature range of 110 ° C to 140 ° C is generally a temperature suitable for thermoforming (including vacuum forming and compressed air forming), and the surface of the thermoforming sheet measured by an infrared sensor using an external heater for heating during thermoforming. It is often performed when the temperature reaches the set value in the temperature range. On the other hand, since the thermoforming sheet is thick, a temperature distribution is likely to occur in the thickness direction (ND) due to heating during thermoforming, and the plasticization behavior in the thermoforming sheet becomes non-uniform. For this reason, when a thermoforming sheet whose storage elastic modulus, which is an index of viscosity, changes significantly in the temperature range of 110 ° C. to 140 ° C. is used, a large difference in moldability is locally generated during thermoforming. Defects such as holes in the thermoformed product are likely to occur. On the other hand, if a thermoforming sheet whose storage elastic modulus does not change significantly in the temperature range of 110 ° C. to 140 ° C. is used, a large difference in moldability does not occur locally during thermoforming, so that a hole is formed in the thermoformed product. Defects such as are less likely to occur.

In one embodiment, the thermoforming sheet (100) has a total light transmittance of 75% or more, preferably 85% or more (for example,) measured according to the measurement method specified in JIS K7361-1-1997. 90-99%). Further, in one embodiment, the thermoforming sheet (100) has a HAZE of 60% or less, preferably 50% or less, more preferably 50% or less, measured in accordance with the measurement method specified in JIS K7136-2000. Is 40% or less, still more preferably 30% or less, even more preferably 20% or less, even more preferably 10% or less, even more preferably 5% or less, for example, 0. It can be in the range of 1-60%. Where total light transmittance and HAZE are parameters related to transparency, showing high total light transmittance and low HAZE means that the heat forming sheet has high transparency. As a result, even when the local protrusion of the structure is covered with the thermoformed product produced by thermoforming the thermoforming sheet, the deterioration of the protrusion can be visually confirmed, so that the structure can be visually confirmed. Deterioration prediction maintenance work becomes easy.

The lower limit of the thickness of the thermoformed sheet (100) is preferably 200 μm or more, more preferably 300 μm or more, and further preferably 350 μm or more, from the viewpoint of shape retention and strength of the thermoformed product. More preferably, it is particularly preferably 400 μm or more. On the other hand, the upper limit of the thickness of the thermoforming sheet (100) is preferably 2,000 μm or less, more preferably 1,600 μm or less, and 1,200 μm or less from the viewpoint of thermoforming property and cost. Is even more preferable. Therefore, in one embodiment, the thickness of the thermoforming sheet (100) can be 200 to 2,000 μm.

(1-1. Fluorine-based resin layer)
The fluorine-based resin layer (110) is provided with the following layers A (110a) and B (110b) in this order from the outside to the inside, so that the structure covered with the thermoformed product has corrosion resistance, weather resistance, and weather resistance. The antifouling property can be significantly improved.
Layer A: Resin composition containing 50 parts by mass or more and 100 parts by mass or less of a polyvinylidene fluoride resin and 0 parts by mass or more and 50 parts by mass or less of a poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things.
Layer B: Resin composition containing 0 parts by mass or more and less than 50 parts by mass of polyvinylidene fluoride resin and more than 50 parts by mass and 100 parts by mass or less of poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things.

Layer A is a resin containing 50 parts by mass or more and 100 parts by mass or less of a polyvinylidene fluoride resin and 0 parts by mass or more and 50 parts by mass or less of a poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). It is a layer composed of a composition. The mixing ratio of the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin in the A layer is 100 parts by mass in total of both, and the polyvinylidene fluoride resin: the poly (meth) acrylic acid ester resin = 95. ~ 55 parts by mass: preferably 5 to 45 parts by mass, more preferably 85 to 60 parts by mass: 15 to 40 parts by mass. When the polyvinylidene fluoride-based resin is 50 parts by mass or more with respect to 100 parts by mass in total of the polyvinylidene fluoride-based resin and the poly (meth) acrylic acid ester-based resin, the characteristics such as weather resistance and stain resistance are improved. be able to. Further, by containing a small amount of poly (meth) acrylic acid ester resin in the A layer, the adhesiveness and adhesion to the B layer can be improved.

In addition to the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin, the layer A includes other resins, plasticizers, heat stabilizers, antioxidants, and light as long as the object of the present invention is not impaired. Stabilizers, crystal nucleating agents, blocking inhibitors, sealability improving agents, mold release agents, coloring agents, pigments, foaming agents, flame retardants and the like can be appropriately contained. However, in general, the total content of the polyvinylidene fluoride-based resin and the poly (meth) acrylic acid ester-based resin in the A layer is 80% by mass or more, typically 90% by mass or more, which is more typical. It is 95% by mass or more, and can be 100% by mass. The A layer may be formed of a single layer or a plurality of layers. Further, although the ultraviolet absorber may be contained in the A layer, it is preferable not to contain it from the viewpoint of cost and bleed-out.

In the present invention, the polyvinylidene fluoride-based resin refers to a homopolymer of vinylidene fluoride, as well as a copolymer of vinylidene fluoride and a monomer copolymerizable with vinylidene fluoride. Examples of the monomer copolymerizable with vinylidene fluoride include vinyl fluoride, ethylene tetrafluoride, propylene hexafluoride, isobutylene hexafluoride, ethylene trifluoride, various alkyl vinyl fluoride ethers, and styrene. , Ethylene, butadiene, known vinyl monomers such as propylene, and the like, and these can be used alone or in combination of two or more. Among these, at least one selected from the group consisting of vinyl fluoride, ethylene tetrafluoroethylene, propylene hexafluoride and ethylene trifluoride is preferable, and propylene hexafluoride is more preferable.

Examples of the polymerization reaction for obtaining a polyvinylidene fluoride-based resin include known polymerization reactions such as radical polymerization and anionic polymerization. In addition, examples of the polymerization method include known polymerization methods such as suspension polymerization and emulsion polymerization. The crystallinity, mechanical properties, etc. of the obtained resin change depending on the polymerization reaction and the polymerization method.

The melting point of the polyvinylidene fluoride-based resin is preferably 150 ° C. or higher, more preferably 160 ° C. or higher. The upper limit of the melting point of the polyvinylidene fluoride-based resin is preferably 170 ° C. or lower, which is equal to the melting point of polyvinylidene fluoride (PVDF).

The melting point of the polyvinylidene fluoride-based resin can be measured by heat flux differential scanning calorimetry (heat flux DSC). For example, a DSC curve (first run) obtained when heating from room temperature to 200 ° C. with a sample mass of 1.5 mg and a heating rate of 10 ° C./min using a differential scanning calorimetry device DSC3100SA manufactured by Bruker AXS Co., Ltd. Can be obtained from.

The MFR of the polyvinylidene fluoride-based resin is preferably 5 to 50 g / 10 minutes under the measurement conditions at 230 ° C. and a load of 3.8 kg in accordance with ISO1133. The higher the MFR, the higher the fluidity during melt extrusion, so the molding processability tends to improve, and the lower the MFR, the higher the impact strength of the laminate tends to be. From the viewpoint of achieving both strength and moldability, the MFR is more preferably 5 to 30 g / 10 minutes, further preferably 10 to 30 g / 10 minutes, and particularly preferably 15 to 26 g / 10 minutes.

The lower limit of the weight average molecular weight (Mw) of the polyvinylidene fluoride-based resin is preferably 40,000 or more, more preferably 50,000 or more, still more preferably 60,000 or more. The upper limit of the weight average molecular weight (Mw) of the polyvinylidene fluoride-based resin is preferably 1,000,000 or less, more preferably 500,000 or less, still more preferably 350,000 or less. The higher the weight average molecular weight (Mw), the higher the impact strength of the laminated sheet tends to be, and the lower the weight average molecular weight (Mw), the higher the fluidity during melt extrusion, and therefore the higher the moldability. .. From the viewpoint of achieving both strength and moldability, the weight average molecular weight (Mw) is preferably 40,000 to 1,000,000, more preferably 50,000 to 500,000, and 60,000 to 350,000. Is more preferable.

The lower limit of the dispersity (Mw / Mn, where Mn is a number average molecular weight) of the polyvinylidene fluoride resin is preferably 1.0 or more, more preferably 1.5 or more, still more preferably 2.0 or more. .. The upper limit of the dispersity (Mw / Mn) of the polyvinylidene fluoride-based resin is preferably 4.0 or less, more preferably 3.5 or less, and even more preferably 3.0 or less. The larger the dispersity (Mw / Mn), the more the thickness accuracy of the laminate tends to improve, and the smaller the dispersity (Mw / Mn), the better the fluidity during melt extrusion, and thus the better the moldability. Tend to do. From the viewpoint of achieving both thickness accuracy and moldability, the dispersity (Mw / Mn) is preferably 1.0 to 4.0, more preferably 1.5 to 3.5, and 2.0 to 3.0. Is more preferable.

The weight average molecular weight (Mw), number average molecular weight (Mn), and dispersity (Mw / Mn) of the polyvinylidene fluoride resin can be measured by gel permeation chromatography (GPC). For example, N, N'-dimethylformamide containing 10 mmol / L lithium bromide can be used as an eluent, and polyethylene oxide, polyethylene glycol, and tetraethylene glycol can be used as standard substances.

In the present invention, the poly (meth) acrylic acid ester-based resin is a copolymer of (meth) acrylic acid ester such as methyl acrylate and methyl methacrylate, and is co-polymerized with (meth) acrylic acid ester and (meth) acrylic acid ester. A copolymer of polymerizable monomers. Examples of the monomer copolymerizable with the (meth) acrylic acid ester include (meth) acrylic acid esters such as butyl (meth) acrylate and ethyl (meth) acrylate; styrene, α-methylstyrene, and p-methyl. Aromatic vinyl monomers such as styrene, o-methylstyrene, t-butylstyrene, divinylbenzene and tristyrene; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; glycidyl groups such as glycidyl (meth) acrylate Monomer; Vinyl carboxylic acid monomer such as vinyl acetate and vinyl butyrate; Olefin monomer such as ethylene, propylene and isobutylene; Diene monomer such as 1,3-butadiene and isoprene; Maleic acid, There are unsaturated carboxylic acid-based monomers such as maleic anhydride and (meth) acrylic acid; enon-based monomers such as vinyl methyl ketone, and these can be used alone or in combination of two or more. .. Among these, a homopolymer of methyl (meth) acrylate or butyl (meth) acrylate is used because of its compatibility with polyvinylidene fluoride resin, sheet strength, adhesion to layer B, and adhesion. An acrylic rubber-modified acrylic copolymer obtained by copolymerizing a monomer mainly composed of methyl (meth) acrylate with an acrylic rubber mainly composed of (meth) is preferable.

Examples of the copolymer include random copolymers, graft copolymers, block copolymers (for example, linear types such as diblock copolymers, triblock copolymers, and gradient copolymers, and star-shaped copolymers polymerized by the arm-first method or the core-first method. Examples thereof include a copolymer (copolymer), a copolymer obtained by polymerization using a macromonomer which is a polymer compound having a polymerizable functional group (macromonomer copolymer), and a mixture thereof. Of these, graft copolymers and block copolymers are preferable from the viewpoint of resin productivity.

Examples of the polymerization reaction for obtaining a poly (meth) acrylic acid ester-based resin include known polymerization reactions such as radical polymerization, living radical polymerization, living anionic polymerization, and living cationic polymerization. Moreover, as a polymerization method, a known polymerization method such as bulk polymerization, suspension polymerization, emulsion polymerization, solution polymerization and the like can be mentioned. The mechanical properties of the obtained resin change depending on the polymerization reaction and the polymerization method.

The MFR of the poly (meth) acrylic acid ester resin conforms to ISO1133, and is preferably 2 to 30 g / 10 minutes under the measurement conditions at 230 ° C. and a load of 10 kg. The higher the MFR, the higher the fluidity during melt extrusion, so the molding processability tends to improve, and the lower the MFR, the higher the impact strength of the sheet tends to be. From the viewpoint of achieving both strength and moldability, the MFR is more preferably 3 to 20 g / 10 minutes, further preferably 4 to 15 g / 10 minutes, and particularly preferably 5 to 10 g / 10 minutes.

The lower limit of the weight average molecular weight (Mw) of the poly (meth) acrylic acid ester resin is preferably 50,000 or more, more preferably 70,000 or more, still more preferably 100,000 or more. The upper limit of the weight average molecular weight (Mw) of the poly (meth) acrylic acid ester resin is preferably 1,000,000 or less, more preferably 750,000 or less, still more preferably 500,000 or less. In order to maintain the impact strength of the laminate, a higher weight average molecular weight (Mw) is preferable, and a lower weight average molecular weight (Mw) improves the fluidity during melt extrusion, so that the molding processability tends to improve. From the viewpoint of achieving both strength and moldability, the weight average molecular weight (Mw) is preferably 50,000 to 1,000,000, more preferably 70,000 to 750,000, and 100,000 to 500,000. More preferred.

The lower limit of the dispersity (Mw / Mn, where Mn is the number average molecular weight) of the poly (meth) acrylic acid ester resin is preferably 1.0 or more, more preferably 1.5 or more, and 2.0 or more. The above is more preferable. The upper limit of the dispersity (Mw / Mn) of the poly (meth) acrylic acid ester resin is preferably 4.0 or less, more preferably 3.5 or less, and even more preferably 3.0 or less. The larger the dispersity (Mw / Mn), the more the thickness accuracy of the laminate tends to improve, and the smaller the dispersity (Mw / Mn), the better the fluidity during melt extrusion, and thus the better the moldability. Tend to do. From the viewpoint of achieving both thickness accuracy and moldability, the dispersity (Mw / Mn) is preferably 1.0 to 4.0, more preferably 1.5 to 3.5, and 2.0 to 3.0. More preferred.

The weight average molecular weight (Mw), number average molecular weight (Mn), and dispersity (Mw / Mn) of the poly (meth) acrylic acid ester resin can be measured by gel permeation chromatography (GPC). For example, tetrahydrofuran can be used as the eluent and polystyrene can be used as the standard substance.

In the acrylic rubber-modified acrylic copolymer, the volume-medium particle size of the rubber-like dispersed particles forming the dispersed phase is preferably 5.0 μm or less. The larger the volume medium particle size, the more dominant the impact strength of the laminate, and the smaller the volume, the more transparent the laminated body. From the viewpoint of achieving both strength and transparency, the volume median particle size is preferably 0.05 to 3.0 μm, more preferably 0.1 to 2.0 μm, and particularly preferably 0.5 to 1.5 μm.

As a method of adjusting the volume medium particle size of the rubber-like dispersed particles, a method of adjusting the stirring speed of the rubber particles in the phase inversion region in the polymerization step, a method of adjusting the amount of the chain transfer agent in the raw material liquid, and the like are used. Can be mentioned.

The volume median particle size of the rubber-like dispersed particles can be determined by, for example, dissolving an acrylic rubber-modified acrylic copolymer in an electrolytic solution (3% tetra-n-butylammonium / 97% dimethylformamide solution) and using the Coulter Multisizer method. 50% by volume particle size of the volume-based cumulative particle size distribution curve measured by (Multisizer II manufactured by Coulter Co., Ltd .; orifice diameter of aperture tube 30 μm) can be used.

The thickness of the layer A is preferably 5 to 100 μm, more preferably 9 to 83 μm, even more preferably 15 to 68 μm, and particularly preferably 17 to 50 μm. When the A layer is 5 μm or more, the function as a protective layer can be improved, and when the A layer is 100 μm or less, cost reduction can be realized. The layer A may be formed of a single layer or a plurality of layers, but it is desirable that the total thickness is within the above-mentioned thickness.

The surface of the A layer on the side where the B layer is laminated is subjected to, for example, corona discharge treatment, plasma treatment (atmospheric pressure and vacuum), high frequency sputtering etching treatment, in order to increase the adhesive strength between the A layer and the B layer. Surface treatment such as frame treatment, etching treatment, excimer UV treatment, and primer treatment may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but the acrylic type is preferable from the viewpoint of increasing the adhesive strength with the B layer.

Further, as will be described later, there is a possibility that an anticorrosion sheet may be overlapped from above on the end portion of the thermoformed product produced by thermoforming the thermoforming sheet. Therefore, the surface of the A layer on the side where the B layer is not laminated is subjected to, for example, corona discharge treatment, plasma treatment (atmospheric pressure and vacuum), high-frequency sputtering etching treatment, and frame treatment in order to increase the adhesive strength with the anticorrosion sheet. , Itro treatment, excimer UV treatment, primer treatment and other surface treatments may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but the acrylic type is preferable from the viewpoint of increasing the adhesive strength with the anticorrosion sheet.

The B layer is a resin containing 0 parts by mass or more and less than 50 parts by mass of a polyvinylidene fluoride resin and more than 50 parts by mass and 100 parts by mass or less of a poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). It is a layer composed of a composition. The mixing ratio of the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin in the B layer is 100 parts by mass in total of both, and the polyvinylidene fluoride resin: the poly (meth) acrylic acid ester resin = 5 ~ 45 parts by mass: preferably 95 to 55 parts by mass, more preferably 15 to 40 parts by mass: 85 to 60 parts by mass. When the poly (meth) acrylic acid ester resin exceeds 50 parts by mass with respect to a total of 100 parts by mass of the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin, the thermoplastic resin layer or the adhesive adhesive Adhesion with the layer can be improved. Further, by containing a small amount of polyvinylidene fluoride-based resin in the B layer, it is possible to improve the weather resistance, the adhesiveness with the A layer, and the adhesiveness.

In addition to the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin, the layer B contains an ultraviolet absorber, other resin, a plasticizer, a heat stabilizer, and an oxidation as long as the object of the present invention is not impaired. An inhibitor, a light stabilizer, a crystal nucleating agent, a blocking inhibitor, a sealability improving agent, a mold release agent, a coloring agent, a pigment, a foaming agent, a flame retardant and the like can be appropriately contained. However, in general, the total content of the polyvinylidene fluoride-based resin and the poly (meth) acrylic acid ester-based resin in the B layer is 80% by mass or more, typically 90% by mass or more, which is more typical. It is 95% by mass or more, and can be 100% by mass.

The B layer preferably contains an ultraviolet absorber. When the B layer contains an ultraviolet absorber, ultraviolet rays are blocked and weather resistance can be effectively enhanced. Examples of the ultraviolet absorber include, but are not limited to, hydroquinone-based, triazine-based, benzotriazole-based, benzophenone-based, cyanoacrylate-based, oxalic acid-based, hindered amine-based, and salicylic acid derivatives, which may be used alone or. Two or more types can be used in combination. Of these, benzotriazole-based and triazine-based compounds are preferable because of their long-lasting UV blocking effect. The content of the ultraviolet absorber in the B layer is preferably 0.05 to 15 parts by mass with respect to 100 parts by mass in total of the polyvinylidene fluoride-based resin and the poly (meth) acrylic acid ester-based resin of the B layer. .. The content of the ultraviolet absorber in the B layer is preferably 0.05 part by mass or more with respect to 100 parts by mass of the total of the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin. By increasing the amount to 2 parts by mass or more, more preferably 2 parts by mass or more is expected to have an effect of further improving weather resistance, an ultraviolet absorbing effect, and an effect of suppressing deterioration of coating and steel surface by imparting UV blocking property. It is possible, and the content of the ultraviolet absorber in the B layer is preferably 15 parts by mass or less with respect to 100 parts by mass of the total of the polyvinylidene fluoride resin and the poly (meth) acrylic acid ester resin. By 10 parts by mass or less, more preferably 5 parts by mass or less, it is possible to prevent the ultraviolet absorber from bleeding out to the surface of the laminate, and to prevent deterioration of adhesion with the A layer. , Cost reduction can be realized.

The thickness of the B layer is preferably 5 to 200 μm, more preferably 15 to 167 μm, even more preferably 30 to 132 μm, and particularly preferably 33 to 100 μm. When the B layer is 5 μm or more, the adhesion to the thermoplastic resin layer or the adhesive adhesive layer can be improved, and when the B layer is 200 μm or less, cost reduction can be realized. The B layer may be formed of a single layer or a plurality of layers, but it is desirable that the total thickness is within the above-mentioned thickness.

The laminate in which the A layer and the B layer are laminated can be produced by, for example, a coextrusion molding method in which a plurality of resins are adhered and laminated in a molten state using a plurality of extrusion molding machines. The coextrusion molding method includes a multi-manifold die method in which multiple resins are made into a sheet and then each layer is contact-bonded at the tip inside the T-die, and a sheet after bonding multiple resins in a merging device (feed block). There is a feed block die method that spreads in a shape, and a dual slot die method in which a plurality of resins are molded into a sheet state and then each layer is brought into contact with the tip of the outside of the T die and bonded. It can also be manufactured by an inflation molding method using a round die.

Further, it is called an extrusion laminating method, and one of the layers to be integrally bonded is formed into a film in advance, and while the other layer is extruded, a heat or adhesive (generally, adhesive adhesion is made in advance). A method of pressure-bonding by (applying an agent) can also be adopted. Further, there is also a method in which both layers are formed into a film in advance and then the two layers are integrated by using heat or an adhesive, but this method is disadvantageous compared to the previous method in terms of the number of steps and cost. ..

When molding a laminate in which the A layer and the B layer are laminated, in order to enhance the transparency of the laminate, it is preferable to use a pinch roll used for taking over the laminate with a mirror finish.

In order to increase the adhesive strength with the A layer, for example, corona discharge treatment, plasma treatment (atmospheric pressure and vacuum), high frequency sputtering etching treatment, frame treatment, etc. Surface treatment such as etching treatment, excimer UV treatment, and primer treatment may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but acrylic type is preferable.

Further, in order to increase the adhesive strength with the thermoplastic resin layer or the adhesive layer on the surface of the B layer on the side where the thermoplastic resin layer or the adhesive layer is laminated, for example, a corona discharge treatment is performed. Surface treatments such as plasma treatment (atmospheric pressure and vacuum), high-frequency sputter etching treatment, frame treatment, itro treatment, excima UV treatment, and primer treatment may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but acrylic type is preferable.

The total thickness of the A layer and the B layer is preferably 10 to 300 μm, more preferably 24 to 250 μm, even more preferably 45 to 200 μm, and particularly preferably 50 to 150 μm. preferable. When the total thickness of the A layer and the B layer is 10 μm or more, a high improvement effect of corrosion resistance, antifouling property and weather resistance can be expected, and when the total thickness is 300 μm or less, cost reduction can be realized. The total thickness of the A layer and the B layer can be formed into a predetermined thickness by using, for example, an extrusion molding machine.

(1-2. Thermoplastic resin layer)
The thermoplastic resin layer (130) is a layer composed of a composition containing one or more kinds of thermoplastic resins.

In order to ensure transparency and thermoformability, one or more types of thermoplastic resins preferably occupy 70% by mass or more, more preferably 80% by mass or more, and 90% by mass or more in the thermoplastic resin layer. It is even more preferable to occupy% by mass or more. The type of thermoplastic resin is not particularly limited, but it is important to select the thermoforming sheet so that the (E'(140 ° C.)) value / (E'(110 ° C.)) value falls within the above range. Is.

The lower limit of the thickness of the thermoplastic resin layer is preferably 100 μm or more, more preferably 200 μm or more, even more preferably 250 μm or more, and particularly preferably 300 μm or more in order to enhance thermoformability. The upper limit of the thickness of the thermoplastic resin layer is preferably 1,990 μm or less, more preferably 1,590 μm or less, still more preferably 1,190 μm or less, from the viewpoint of thermoformability and cost. The thermoplastic resin layer may be formed of a single layer or a plurality of layers, but it is desirable that the total thickness is within the above-mentioned thickness.

In a preferred embodiment, the thickness of the thermoplastic resin layer (T ₁ ) can be equal to or greater than the total thickness of the layers A and B (T _2). More specifically, _{it is preferable to satisfy 1.0 ≤ T 1} / T ₂ ≤ 200, more preferably 1.5 ≤ T ₁ / T ₂ ≤ 100, and 2.0 ≤ T ₁ / T ₂ It is even more preferable to satisfy ≦ 50, even more preferably to satisfy 2.5 ≦ T ₁ / T ₂ ≦ 30, and particularly preferably to satisfy 5 ≦ T1 / T2 ≦ 25.

In a preferred embodiment, the thermoplastic resin layer does not contain a fluororesin such as a polyvinylidene fluoride-based resin. Generally, fluorine-based resins are more expensive than other resins. Therefore, in the thermoforming sheet according to the preferred embodiment of the present invention, a thermoplastic resin containing no fluorine-based resin while ensuring functions such as corrosion resistance, weather resistance and antifouling property by the fluorine-based resin layer (110). The layer (130) improves thermoformability. With this configuration, it is possible to obtain a thermoformed product that can be manufactured at low cost while having functions such as corrosion resistance, weather resistance, and stain resistance.

The thermoplastic resin layer contains one or more selected from the group consisting of poly (meth) acrylic acid ester-based resin, polyvinyl chloride-based resin, polycarbonate-based resin, polyethylene terephthalate-based resin, and polyamide-based resin. Is preferable. By using these resins, it is possible to easily control the (E'(140 ° C.)) value / (E'(110 ° C.)) value of the thermoforming sheet within the above-mentioned range, and it is also possible to control the value on the market. It is very convenient because it is easy to obtain.

Polyvinyl chloride-based resins include polyvinyl chloride, chlorinated polyethylene, and resins obtained by copolymerizing vinyl chloride and a comonomer component (eg, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene copolymer). , Vinyl chloride-propylene copolymer). The polyvinyl chloride resin may be used alone or in combination of two or more.

Polycarbonate-based resins are resins in which a carbonate group is mainly responsible for bonding the monomers. Examples of the polycarbonate resin include those obtained by reacting one or more kinds of bisphenols with phosgene or carbonic acid diester, or those obtained by reacting one or more kinds of bisphenols with diphenyl carbonates by a transesterification method. Can be mentioned. Examples of the bisphenols include bis- (4-hydroxyphenyl) -alkane represented by bisphenol A, bis- (4-hydroxyphenyl) -cycloalkane, and bis- (4-hydroxyphenyl) -sulfide. Examples thereof include bis- (4-hydroxyphenyl) -ether, bis- (4-hydroxyphenyl) -ketone, bis- (4-hydroxyphenyl) -sulfone, bisphenol fluorene and the like. Further, for the purpose of improving processing characteristics or the like, a compound obtained by copolymerizing a compound such as hydroquinone or 4,4-dihydroxybiphenyl as a divalent phenol other than bisphenols as a copolymer is also preferably used. The polycarbonate resin may be used alone or in combination of two or more.

The polyethylene terephthalate resin is a resin containing terephthalic acid as a dicarboxylic acid component and ethylene glycol as a diol component as main components of the monomer. Other comonomer components may be copolymerized in order to suppress crystallization during molding, improve processability, and the like. Specific examples of the comonomer component include isophthalic acid, sebacic acid, adipic acid, azelaic acid and the like as the dicarboxylic acid component, and diethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, butanediol and the like as the diol component. .. The polyethylene terephthalate resin may be used alone or in combination of two or more.

Polyamide-based resins are resins in which amide groups mainly carry the bonds between monomers. As the polyamide resin, any of an aliphatic polyamide resin, an alicyclic polyamide resin and an aromatic polyamide resin can be used. Examples of the aliphatic polyamide include polyamide 46, polyamide 6, polyamide 66, polyamide 610, polyamide 612, polyamide 9, polyamide 11, polyamide 12, polyamide 6/66, and polyamide 66/610. Examples of the alicyclic polyamide include poly-1,4-norbornene terephthalamide, poly-1,4-cyclohexane terephthalamide, and poly-1,4-cyclohexane-1,4-cyclohexaneamide. Examples of the aromatic polyamide include polyamide 4T, polyamide 5T, polyamide M-5T, polyamide 6T, polyamide 9T, polyamide 10T, polyamide 11T, polyamide 12T, polyamide MXD6, polyamide PXD6, polyamide MXD10, polyamide PXD6, polyamide 6I, polyamide PACMT, Examples thereof include polyamide PACMI, polyamide PACM12, and polyamide PACM14. The polyamide resin may be used alone or in combination of two or more.

The thermoplastic resin layer has other resins, plasticizers, heat stabilizers, antioxidants, light stabilizers, ultraviolet absorbers, crystal nucleating agents, blocking inhibitors, and sealing properties as long as the object of the present invention is not impaired. An improver, a mold release agent, a colorant, a pigment, a foaming agent, a flame retardant and the like can be appropriately contained. However, in general, the total content concentration of the poly (meth) acrylic acid ester resin, the polyvinyl chloride resin, the polycarbonate resin, the polyethylene terephthalate resin, and the polyamide resin in the thermoplastic resin layer is 80% by mass or more. It is typically 90% by mass or more, more typically 95% by mass or more, and can also be 100% by mass.

The surface of the thermoplastic resin layer on the side where the B layer or the adhesive layer is laminated is subjected to, for example, corona discharge treatment in order to increase the adhesive strength between the B layer or the adhesive layer and the thermoplastic resin layer. , Plasma treatment (atmospheric pressure and vacuum), high frequency sputter etching treatment, frame treatment, itro treatment, excima UV treatment, primer treatment and the like may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but the acrylic type is preferable from the viewpoint of increasing the adhesive strength with the B layer.

Further, the end portion of the thermoformed product produced by thermoforming the thermoforming sheet may be overlapped on the anticorrosion sheet as described later. Therefore, in order to increase the adhesive strength with the anticorrosion sheet, for example, corona discharge treatment, plasma treatment (atmospheric pressure, and vacuum) are applied to the surface of the thermoplastic resin layer on the side where the B layer or the adhesive layer is not laminated. , High-frequency spatter etching treatment, frame treatment, itro treatment, excimer UV treatment, primer treatment, and other surface treatments may be performed. Further, a roughening treatment such as physically scraping the surface may be performed by sandpaper, keren, blasting or the like. Examples of the primer include acrylic type, ethylene vinyl acetate type, urethane type and epoxy type, but the acrylic type is preferable from the viewpoint of increasing the adhesive strength with the anticorrosion sheet.

(1-3. Adhesive layer)
The adhesive layer (120) is a layer composed of an adhesive, and can be adopted to enhance the adhesion between the B layer and the thermoplastic resin layer, if necessary. In the present invention, the adhesive refers to an adhesive, an adhesive, or a mixture of both. In the present invention, the difference between the adhesive and the adhesive is that the adhesive is a soft gel-like solid from the time of bonding, and spreads wet on the adherend as it is, and after that, the state does not change and peeling occurs. Demonstrate the power to resist. In other words, the adhesive develops an adhesive force that can withstand practical use as soon as it is bonded, whereas when the adhesive is bonded, it wets and spreads on the bonding interface with a fluid liquid, and then changes to a solid by a chemical reaction. , It is firmly bonded at the interface and exerts the power to resist peeling. After the adhesives are bonded together, it takes time for the adhesives to solidify by a chemical reaction before they develop a practically usable adhesive force. The type of adhesive used may be appropriately determined depending on the materials of the B layer and the thermoplastic resin layer.

The thickness of the adhesive layer is not particularly limited. Generally, as the thickness of the adhesive layer becomes smaller, the adhesion to the adherend tends to decrease. Therefore, for example, it is preferably 5 μm or more, more preferably 10 μm or more. It is even more preferably 15 μm or more, and particularly preferably 20 μm or more. When the thickness of the adhesive layer exceeds 150 μm, various performances due to the adhesive layer tend to reach a plateau, and the cost is high. Therefore, the thickness is preferably 150 μm or less, preferably 110 μm. It is more preferably less than or equal to, even more preferably 100 μm or less, and particularly preferably 75 μm or less. From these viewpoints, the thickness of the adhesive layer is preferably 5 to 150 μm, more preferably 10 to 110 μm, even more preferably 15 to 100 μm, and 20 to 75 μm. Is particularly preferred. The thickness means the thickness (μm / Dry) after the adhesive layer is dried or after the reaction.

Examples of the adhesive include rubber adhesives, (meth) acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone adhesives, and poly. Examples thereof include acrylamide-based pressure-sensitive adhesives and cellulose-based pressure-sensitive adhesives. Such an adhesive may be used alone or in combination of two or more.

Adhesives can be classified into hot-melt adhesives, two-component mixed adhesives, thermosetting adhesives, UV-curable adhesives, etc., and are easy to handle and stable. A two-component mixed type pressure-sensitive adhesive is preferably available for the reason of developing the adhesive strength.

Among these, the two-component mixed (meth) acrylic pressure-sensitive adhesive can be preferably used from the viewpoint of being transparent and having excellent adhesiveness. (Meta) acrylic means both acrylic and methacrylic. Details of the (meth) acrylic pressure-sensitive adhesive preferably used in the present invention are described in International Publication No. 2016/010013.

Specific examples of the (meth) acrylic pressure-sensitive adhesive include ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and n-pentyl (meth) acrylate. , 2-Methylbutyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) _{) At least one of C 2 to} C ₁₂ alkyl esters of (meth) acrylic acid such as acrylate (monomer A), acrylic acid, methacrylate, acrylamide, N-methylol acrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl. A copolymer with at least one kind (monomer B) of a functional group-containing acrylic monomer such as methacrylate can be preferably used. The copolymerization ratio of the monomer A and the monomer B is represented by a mass ratio of 100 parts by mass of the total of the monomer A and the monomer B, and the monomer A / monomer B = 99.9 / 0.1 to 70/30. It is preferably in the range of 99/1 to 75/25.

Particularly suitable (meth) acrylic copolymers include copolymers of butyl acrylate (BA) and acrylic acid (AA). In this case, the copolymerization ratio of butyl acrylate (BA) and acrylic acid (AA) is expressed as a mass ratio in a total of 100 parts by mass of BA and AA, and BA / AA = 99.9 / 0.1 to 70/30. It is preferably in the range of 99.5 / 0.5 to 80/20. When AA is 0.1 part by mass or more out of 100 parts by mass of BA and AA in total, it becomes easy to control the adhesive physical properties by using a cross-linking agent in combination. Further, when AA is 30 parts by mass or less out of a total of 100 parts by mass of BA and AA, the glass transition point (Tg) is lowered, sticking at a low temperature is improved, and workability is also improved.

The weight average molecular weight (Mw) of the (meth) acrylic copolymer is preferably 200,000 to 1,000,000, more preferably 400,000 to 800,000, and the molecular weight is such that the polymerization initiator. It can be adjusted by the amount of the chain transfer agent and by adding a chain transfer agent. When the weight average molecular weight (Mw) is 200,000 or more, the cohesive force of the (meth) acrylic copolymer is improved, and the strength of the adhesive layer can be increased. Further, when it is 1,000,000 or less, appropriate flexibility can be obtained for the (meth) acrylic copolymer.

Additives such as a cross-linking agent, a tackifier, an ultraviolet absorber, and a light stabilizer can be added to the pressure-sensitive adhesive, if necessary.

Examples of the cross-linking agent include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, and amine-based cross-linking agents. These may be used alone or in combination of two or more. A particularly suitable cross-linking agent is an isocyanate-based cross-linking agent, and the isocyanate-based cross-linking agent is 0.3 to 4 with respect to 100 parts by mass of a monomer (for example, the total of BA and AA) which is a constituent unit of the polymer constituting the pressure-sensitive adhesive. It is a mass portion, preferably 0.5 to 3 parts by mass. When the isocyanate-based cross-linking agent is 0.3 parts by mass or more, the cohesive force of the pressure-sensitive adhesive is improved, and the strength of the pressure-sensitive adhesive layer can be increased. Further, when the amount of the isocyanate-based cross-linking agent is 4 parts by mass or less, appropriate flexibility can be obtained for the pressure-sensitive adhesive.

Specific examples of the isocyanate-based cross-linking agent include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4'-diisocyanate, and the like. Polyvalent isocyanate compounds such as diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethanediisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate, etc. , And these polymers (polyisocyanate compounds), chain or cyclic aliphatic polyisocyanate compounds typified by hydrogenated products of polyisocyanate compounds, biuret, dimer, and trimer of these polyisocyanate compounds. Alternatively, a pentamer, an adduct of these polyisocyanate compounds and a polyol compound such as trimethylolpropane, and the like can be mentioned. These may be used alone or in combination of two or more.

When the pressure-sensitive adhesive contains a crosslinked product of a (meth) acrylic copolymer, the degree of cross-linking (gel fraction) of the adhesive layer is not particularly limited, but is preferably 10% by mass or more, preferably 15% by mass, for example. The above is more preferable, 20% by mass or more is further preferable, and 25% by mass or more is particularly preferable. The degree of cross-linking (gel fraction) of the adhesive layer is preferably 80% by mass or less, more preferably 75% by mass or less, further preferably 70% by mass or less, and particularly preferably 60% by mass or less. That is, the degree of cross-linking (gel fraction) of the adhesive layer is, for example, preferably 10 to 80% by mass, more preferably 15 to 75% by mass, further preferably 20 to 70% by mass, and 25 to 60% by mass. Is particularly preferable. The degree of cross-linking (gel fraction) should be adjusted by, for example, the composition of the base polymer (adhesive) of the (meth) acrylic copolymer, the molecular weight, the presence or absence of the cross-linking agent, its type, and the selection of the amount used. Can be done. In principle, the upper limit of the degree of cross-linking is 100% by mass.

The tackifier can be selected in consideration of the softening point, compatibility with each component, and the like. For example, terpene resin, rosin resin, hydrogenated rosin resin, kumaron inden resin, styrene resin, aliphatic petroleum resin, alicyclic petroleum resin, terpene-phenol resin, xylene resin, and other aliphatic hydrocarbon resins. Alternatively, an aromatic hydrocarbon resin or the like can be mentioned. These may be used alone or in combination of two or more.

The ultraviolet absorber can be selected in consideration of the ultraviolet absorbing ability, compatibility with the (meth) acrylic pressure-sensitive adhesive to be used, and the like. For example, hydroquinone type, benzotriazole type, benzophenone type, triazine type, cyanoacrylate type and the like can be mentioned. These may be used alone or in combination of two or more.

The light stabilizer can be selected in consideration of compatibility with the (meth) acrylic pressure-sensitive adhesive to be used, thickness, and the like. For example, hindered amine compounds, hindered phenol compounds, benzoate compounds, nickel complex salt compounds and the like can be mentioned. These may be used alone or in combination of two or more.

When the adhesive layer is composed of an adhesive, the adhesive layer can be formed by a general method. For example, there is a method (direct coating method) in which an adhesive is directly applied to the bonding surface of the B layer with the thermoplastic resin layer and / or the bonding surface of the thermoplastic resin layer with the B layer and dried. Another method is to apply an adhesive to the separator, dry it, and then attach it to the base material (B layer and / or thermoplastic resin layer).

The coating of the adhesive can be performed using a conventionally known coating device such as a gravure roll coater, a die coater, a bar coater, a doctor blade, a comma coater, and a reverse coater. Further, the adhesive may be applied by impregnation, curtain coating method or the like. If necessary, the adhesive may be applied while cooling, heating, or irradiating with an electron beam.

Drying after applying the pressure-sensitive adhesive is preferably performed under heating from the viewpoint of promoting the cross-linking reaction and improving the production efficiency. The drying temperature is, for example, 40 ° C. or higher (usually 60 ° C. or higher), preferably about 150 ° C. or lower (usually 130 ° C. or lower).

In the step of forming the adhesive layer, after the adhesive is applied and dried, the component transfer in the adhesive layer is adjusted, the cross-linking reaction proceeds, and the substrate (for example, A) is formed. Aging may be performed for the purpose of alleviating the strain that may exist in the layer (layer, B layer, thermoplastic resin layer) and the adhesive layer.

Adhesives include (meth) acrylic resin adhesives, natural rubber adhesives, urethane resin adhesives, ethylene-vinyl acetate resin emulsion adhesives, ethylene-vinyl acetate resin adhesives, epoxy resin adhesives, chlorides. Vinyl resin solvent-based adhesive, chloroprene rubber-based adhesive, cyanoacrylate-based adhesive, silicone-based adhesive, styrene-butadiene rubber solvent-based adhesive, nitrile rubber-based adhesive, nitrocellulose-based adhesive, phenol resin-based adhesive , Modified silicone adhesive, polyester adhesive, polyamide adhesive, polyimide adhesive, olefin resin adhesive, vinyl acetate resin emulsion adhesive, polystyrene resin solvent adhesive, polyvinyl alcohol adhesive, polyvinyl Examples thereof include pyrrolidone resin adhesives, polyvinyl butyral adhesives, polybenzimidazole adhesives, polymethacrylate resin solvent adhesives, melamine resin adhesives, urea resin adhesives, resorcinol adhesives and the like. The adhesive may be used alone or in combination of two or more.

Adhesives can be classified into hot melt adhesives, two-component curable adhesives, heat-curable adhesives, UV curable adhesives, etc. when classified by adhesive form, and among these, ease of handling and stability. Two-component curable adhesives, heat-curable adhesives, and UV-curable adhesives are preferably available for the reason of developing the adhesive strength.

Among the above adhesives, a (meth) acrylic resin-based two-component curable adhesive is preferable because of its ease of handling and stable adhesive strength development.

As for the adhesive, additives such as the above-mentioned cross-linking agent, tackifier, ultraviolet absorber, and light stabilizer can be added, if necessary. Further, a rocking agent, a pigment, a defoaming agent, a diluent, a curing rate adjusting agent and the like can be added as long as the performance is not affected.

When the adhesive layer is composed of an adhesive, the adhesive layer can be formed by a general method. For example, a method of directly applying an adhesive to the bonding surface of the B layer with the thermoplastic resin layer and / or the bonding surface of the thermoplastic resin layer with the B layer can be mentioned. As a method for curing the adhesive, an appropriate method (heating, UV irradiation, etc.) may be adopted according to the type of adhesive after the B layer and the thermoplastic resin layer are bonded to each other via the adhesive layer. ..

Examples of the adhesive coating include a solvent type dry laminating method, a solventless type dry laminating method, a wet laminating method, a hot melt laminating method, and the like, and these methods may be appropriately used. Of these, the most suitable coating method is the solvent-based dry laminating method.

As the organic solvent used in the solvent type dry laminating method, any solvent having solubility in the adhesive can be used. For example, water-insoluble solvents such as toluene, xylene, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, 1-methoxy- Glycol ethers such as 2-propanol, 1-ethoxy-2-propanol, 1-propanol-2-propanol, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, acetaldehyde , Araldehydes such as propionaldehyde, aprotonic polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone and the like.

The solvent-diluted adhesive can be diluted at a concentration such that the Zahn Cup (No. 3) viscosity is in the range of 5 to 30 seconds (25 ° C.). If the viscosity of the Zahn cup (No. 3) is 5 seconds or more, the adhesive is sufficiently applied to the object to be coated, and the roll is not contaminated. Further, when the viscosity of the Zahn cup (No. 3) is 30 seconds or less, the adhesive is sufficiently transferred to the roll, and a uniform adhesive layer can be easily formed. For example, in dry laminating, the Zahn Cup (No. 3) viscosity is preferably 10 to 20 seconds (25 ° C.) during its use.

Further, when a solvent is used, the solvent drying temperature after applying the adhesive may be various from 20 ° C. to 140 ° C., but it is close to the boiling point of the solvent and has an influence on the object to be coated. A temperature that does not reach is desirable. If the drying temperature is less than 20 ° C., the solvent remains in the sheet, which causes poor adhesion and odor. Further, if the drying temperature exceeds 140 ° C., it becomes difficult to obtain a sheet having a good appearance due to softening of the sheet or the like. Therefore, the solvent drying temperature is preferably, for example, 40 to 120 ° C.

As the coating type for applying the adhesive, any of the commonly used coating types such as roll coating, spray coating, air knife coating, dipping, and brush coating can be used, but roll coating or spray coating can be used. preferable.

<2. Thermoformed products>
The thermoformed sheet (100) according to the present invention can be thermoformed to produce a thermoformed product. The thermoforming is preferably carried out by heating the thermoforming sheet in a temperature range of 110 ° C. to 140 ° C. The shape of the thermoformed product may be appropriately determined according to the outer shape of the protrusion to be covered, but for example, when covering bolts and nuts, the shape of the bolt / nut cap can be used. Using an adhesive, the bolt-nut cap is fixed to the desired surface (generally the surface of the structure to which the bolt and nut are fixed) so as to cover the protrusions of one or both of the bolt and nut. , Bolts and nuts, or both can be protected or repaired. It is preferable that both the bolt / nut cap and the adhesive are transparent because the deterioration status of the coated protrusions (eg, bolts and nuts) can be visually recognized. As the adhesive, the adhesive mentioned in the description of the adhesive layer can be preferably used. The detailed description of the adhesive has already been described and will be omitted.

Thermoforming is a molding method in which a thermoplastic resin sheet such as a thermoforming sheet is heated and softened, and then the plasticized sheet is deformed along a mold to be molded. Any conventionally known thermoforming method can be used. Used. For example, vacuum forming, compressed air forming, vacuum forming, press forming, match molding and the like can be mentioned. One or more thermoforming methods may be combined.

Vacuum forming is a molding method in which a thermoplastic resin sheet such as a thermoforming sheet is heated and softened, a vacuum is created between the mold and the sheet, and the sheet is brought into close contact with the mold at atmospheric pressure. Vacuum forming method is used.

Pneumatic molding is a molding method in which a thermoplastic resin sheet such as a thermoforming sheet is heated and softened, and the sheet is brought into close contact with a mold by using the pressure of compressed air. Is used.

The vacuum pressure air forming is a thermoforming method that combines vacuum forming and pressure air forming, and any conventionally known vacuum pressure air forming method is used.

Press molding is a molding method in which a thermoplastic resin sheet such as a thermoforming sheet is heated and softened, and then the plasticized sheet is pressed by upper and lower molds to be molded. Any conventionally known press molding method can be used. Used.

Match molding is a molding method in which a thermoplastic resin sheet such as a thermoforming sheet is heated and softened, and then the plasticized sheets are contacted with a pair of male and female molds to form the plasticized sheet. A match mold molding method is used.

Any conventionally known method is used as the heating method for the thermoforming sheet. Examples thereof include radiant heating, contact heating, and hot air heating, and these may be used in combination.

As the mold for thermoforming a molded product such as a bolt, nut cap, or the like, a conventionally known arbitrary shape or method is used. For example, a straight type (female type) and a drape type (male type) can be mentioned. In addition to these, a plug assist method in which the sheet is pressed against the mold with an auxiliary mold (plug) at the same time as vacuum suction, or a vacuum after inflating the sheet with compressed air. A suction air slip method may be combined.

Bolts and nuts caps are thermoformed to any shape according to the shape of the bolt or nut. There are no particular restrictions on bolts and nuts, but for example, high-strength bolts, high-strength hexagon bolts, Torsia-type high-strength bolts, hot-dip zinc-plated high-strength bolts, rust-preventive high-strength bolts, weather-resistant steel high-strength bolts, and fire-resistant steel. High-strength bolts, beach weather-resistant steel high-strength bolts, ultra-high-strength bolts, etc. are used. Examples of the standard include JIS B1186: 2013.

Before fixing the bolt-nut cap with an adhesive, caulking or painting may be performed for the purpose of filling the gap between the bolt and / or the nut and improving airtightness and waterproofness. The material used for caulking is not particularly limited, but for example, a commercially available caulking material, a sealing material, or the like may be used, or an adhesive used for a bolt / nut cap may be used. The coating is not particularly limited, but for example, the coating described later may be used.

The thermoformed product is formed by covering the protrusions such as bolts and nuts so that the fluorine-based resin layer (110) is located on the outside and the thermoplastic resin layer (130) is located on the inside. It is possible to remarkably improve the corrosion resistance and weather resistance of the resin.

FIG. 3a shows a schematic side view of the bolt / nut cap (300a) according to the first embodiment of the present invention. The bolt / nut cap (300a) includes an A layer, a B layer, and a thermoplastic resin layer in this order from the outer surface (301a) shown by the solid line to the inner surface (302a) shown by the broken line. The bolt / nut cap (300a) has a main body (310a) for accommodating a protruding portion (500) of a bolt and a nut virtually indicated by a dotted line, and a main body (310a) for the protruding portion (500) of the bolt and the nut. It is provided with an opening (330a) for introduction into the bolt and a flange portion (320a) to be adhered to a surface on which bolts and nuts are fixed. More specifically, the protruding portions (500) of the bolts and nuts include a first step portion (310a1) covering the washer (500a), a second step portion (310a2) covering the nut (500b), and a nut (500b). It is provided with a third step portion (310a3) that covers the tip portion (500c) of the bolt protruding from the bolt. The flange portion (320a) has a flange shape extending radially from the opening portion (330a).

FIG. 3b shows a schematic side view of the bolt / nut cap (300b) according to the second embodiment of the present invention. The bolt / nut cap (300b) includes an A layer, a B layer, and a thermoplastic resin layer in this order from the outer surface (301b) shown by the solid line to the inner surface (302b) shown by the broken line. The bolt / nut cap (300b) introduces the main body (310b) for accommodating the bolt head (600) virtually indicated by the dotted line and the bolt head (600) into the main body (310b). It is provided with an opening (330b) for the purpose and a collar portion (320b) to be adhered to the surface to which the bolt is fixed. The flange portion (320b) has a flange shape extending radially from the opening portion (330b).

The bolt-nut cap according to the present invention can be used, for example, for protecting one or both of bolts and nuts constituting a newly constructed steel structure. By covering one or both of the bolts and nuts constituting the newly constructed steel structure with the bolts and nuts cap according to the present invention, it is possible to improve the corrosion resistance and the weather resistance. Further, the bolt / nut cap according to the present invention can be used for repairing one or both of bolts and nuts constituting an existing steel structure. By covering one or both of the bolts and nuts constituting the existing steel structure with the bolt-nut cap according to the present invention, deterioration of one or both of the bolts and nuts due to corrosion, rust, etc. progresses more than the present situation. Can be delayed.

Therefore, in one embodiment, the present invention uses an adhesive to fix the thermoformed product according to the present invention so as to cover one or both protrusions of the bolt and nut. Or both provide protection or repair methods.

Further, in one embodiment, the present invention
A method for protecting or repairing a steel structure including a steel material and bolts and nuts fixed to the steel material.
A step of fixing the thermoformed product according to the present invention to the surface of the steel material by using an adhesive so as to cover the protrusions of one or both of the bolt and the nut.
The process of attaching the anticorrosion sheet to the surface of the steel material and
Provide protection or repair methods including.

Referring to FIG. 4a, a nut 500b is screwed into a bolt tip (500c) inserted into a bolt hole (430) formed in a steel material (400) via a washer (500a). Further, the protruding portion (500) of the bolt and nut fixed to the steel material (400) using the bolt and nut caps (300a, 300b) according to the first and second embodiments of the present invention, and the head of the bolt ( 600) is covered. The inner surface of the collar portion (320a, 320b) of the bolt / nut cap (300a, 300b) can be adhered to the surface (410) of the steel material via the adhesive (700).

Further, the anticorrosion sheet (800) may be attached to the surface (410) of the steel material. As shown in FIG. 4a, by superimposing the end portion of the anticorrosion sheet (800) on the collar portion (320a, 320b) of the bolt nut cap, the anticorrosion sheet (800) and the bolt nut cap (300a, 300b) can be separated. It is possible to configure so that there is no uncovered portion between them. Alternatively, on the contrary, as shown in FIG. 4b, the anticorrosion sheet (800) is first attached to the surface (410) of the steel material, and then the end portion of the anticorrosion sheet (800) (in the present embodiment). By superimposing the flanges (320a, 320b) of the bolt / nut cap on the annular end formed along the outer circumference of the hole (430), the anticorrosion sheet (800) and the bolt / nut cap (300a, It is also possible to configure so that there is no uncovered portion between 300b). In the embodiment shown in FIG. 4b, the inner surface of the collar portion (320a, 320b) of the bolt / nut cap (300a, 300b) can be adhered to the anticorrosion sheet (800) via the adhesive (700). At this time, it is preferable that the adhesive (700) adheres to both the anticorrosion sheet (800) and the surface of the steel material (410). With this configuration, when the anticorrosion sheet (800) is peeled off, it is possible to prevent the bolts and nut caps (300a, 300b) from being peeled off together.

The structure of the bolt / nut cap can be appropriately deformed according to the shape of the bolt and the nut. For example, FIG. 4c shows a schematic side sectional view of a bolt-nut cap (300c, 300d) and a steel material (400) when a torusia-type high-strength bolt fixed to a steel material is covered with a bolt-nut cap. There is. Further, FIG. 4d shows a schematic side sectional view of the bolt-nut cap (300e, 300f) and the steel material (400) when the combination of the hexagon bolt and the hexagon nut fixed to the steel material is covered with the bolt-nut cap. Has been done. In the embodiment shown in FIG. 4d, both the hexagon bolt and the hexagon nut are fixed to the steel material (400) with a washer (500a, 600a) sandwiched between them. Further, the bolt / nut caps (300c, 300d, 300e, 300f) can be fixed to the surface (410) of the steel material via an adhesive (not shown), respectively. Note that, in FIGS. 4c and 4d, the same reference numerals as those in FIG. 4a have the same meanings as those described in the description of FIG.

The surface of the steel material (400) may not be coated with a paint, but is generally coated with a paint, and typically a rust preventive paint is applied. For this reason, the surface of the steel material is generally protected by a coating film, typically a rust preventive coating film. Examples of the rust preventive paint include, but are not limited to, fluororesin paint, polyurethane resin paint, and epoxy resin paint. These may be used alone, but are preferably used in combination in order to enhance the corrosion resistance. When painting, it is preferable to pre-treat the surface of the steel material by blasting or the like in order to improve the adhesion of the painting.

In a preferred embodiment, the surface of the steel material constituting the steel structure can be subjected to a heavy-duty anticorrosion coating including four layers of an anticorrosion base, an undercoat layer, an intermediate coating layer, and a topcoat layer. Examples of the paint for the anticorrosion base include inorganic zinc rich paint and organic zinc rich paint. Examples of the paint forming the undercoat layer include an epoxy resin paint. Examples of the paint forming the intermediate coating layer include an epoxy resin paint and a fluororesin paint. Examples of the paint forming the topcoat layer include a fluororesin paint and a polyurethane resin paint. The paint forming each layer may be used alone, or a plurality of types may be mixed and used. An example of a heavy-duty anticorrosion coating process is the C-5 coating system described in the Steel Road Bridge Painting / Anticorrosion Handbook (Japan Road Association).

Steel structures are not particularly restricted, but for example, bridges, water gates, steel towers, pipelines, offshore structures, gas tanks, plants, wind power propeller towers, buildings, factories, warehouses, parking lots, fences, roofs (eg high speed). (Structures that support a net to prevent flying balls from a golf course into the road), steel structures such as undulating gates that are installed outdoors. Since the steel structure installed outdoors is exposed to an environment that is easily corroded by the adhesion of moisture and salt, the effect of using the thermoformed product according to the present invention is remarkable.

On the surface of the steel material constituting the steel structure, there are a portion where a desired coating film thickness can be easily secured and a portion where it is difficult to secure a desired coating film thickness. In steel structures, rust and corrosion often occur starting from a portion where it is difficult to secure a coating film thickness. Therefore, it is preferable to attach an anticorrosion sheet to a portion where it is difficult to secure such a coating film thickness in order to protect or repair the steel structure. Even if the anticorrosion sheet is not attached to the entire surface of the steel material that constitutes the steel structure, if the anticorrosion sheet can be attached to the part where it is difficult to secure the coating film thickness, a high protection or repair effect can be obtained, which is economical. Is.

The portion where it is difficult to secure the coating film thickness includes, but is not limited to, a member corner portion (edge surface), a welded portion, a ridge portion, a corner portion (polygon apex portion), and the like. The corner portion (edge surface) of the member refers to an exposed plate-thick surface of the plate-shaped portion when the steel material constituting the steel structure has a plate-shaped portion. The length of the member corner portion (edge surface) in the plate thickness direction is not limited, but is generally 1.6 to 100 mm, and typically 9 to 50 mm.

When the anticorrosion sheet is attached to the corner portion (edge surface) of the steel material constituting the steel structure, it is possible to attach the anticorrosion sheet only to the corner portion (edge surface) of the member. As shown in, it is attached to the member corner portion (edge surface) (410a) over at least a part of each of the pair of flat surface portions (410b, 410c) adjacent to the member corner portion (edge surface) (410a). However, it is more preferable in increasing the durability of the steel structure. With this configuration, the anticorrosion sheet (800) can be attached to the corners (edge surfaces) (410a) and ridges (410d) of the members at the same time, which is efficient. In the embodiment shown in FIG. 5, the flat surface portion (410b, 410c) of the steel material surface (410) has an uncoated portion not covered by the anticorrosion sheet (800) or the bolt / nut cap (300a, 300b). However, since the uncoated portion is a portion where the coating film thickness can be easily secured, there is no big problem even if it is not necessarily covered by these.

Examples of the anticorrosion sheet include resin sheets, particularly fluororesin sheets, poly (meth) acrylic acid ester sheets, high-density polyethylene sheets, polypropylene sheets, polyvinyl chloride sheets, etc., but are limited to these sheets. However, a known anticorrosion sheet may be selected according to the required characteristics.

As a particularly suitable anticorrosion sheet, a fluorine-based resin layer and a pressure-sensitive adhesive layer containing one or both selected from the group consisting of polyvinylidene fluoride-based resin and ethylene-chlorotrifluoroethylene copolymer are formed from the outside to the inside. Examples thereof include anticorrosion sheets having a laminated structure provided in this order. In particular, an anticorrosion sheet having a laminated structure in which the A layer, the B layer and the pressure-sensitive adhesive layer are provided in this order from the outside to the inside is preferable. The pressure-sensitive adhesive layer can preferably contain, for example, the above-mentioned pressure-sensitive adhesive. This anticorrosion sheet is used by attaching the adhesive layer to the surface of the steel material as the attachment side.

Hereinafter, the present invention will be described in detail based on Examples in comparison with Comparative Examples.

(1. Preparation of various sheets)
<Molding Examples 1 to 25: Fluorine Resin Sheet>
PVDF1: As a polyvinylidene fluoride resin, a trade name Kynar720 manufactured by Arkema (a homopolymer of vinylidene fluoride, MFR (ISO1133 compliant, 230 ° C., 3.8 kg load): 18 to 26 g / 10 minutes) was prepared.
Acrylic 1: As a poly (meth) acrylic acid ester resin, trade name Hypet HBS000Z60 (methyl methacrylate-butyl acrylate copolymer, MFR (ISO1133 compliant, 230 ° C, 10 kg weighted): 5-9 g / 10 minutes) was prepared.
UVA1: As a benzotriazole-based ultraviolet absorber, a trade name of Tinuvin 234 manufactured by BASF was prepared.
UVA2: As a triazine-based ultraviolet absorber, a trade name of Tinuvin1577ED manufactured by BASF was prepared.

Blend in a predetermined ratio according to the molding number so that the content of each material with respect to the total mass of the resin composition constituting the A layer becomes the value shown in Table 1, and then use a φ30 mm different direction rotating twin-screw extruder (Kobe). Using KTX-30) manufactured by Kobe Steel, Ltd., the mixture was melt-kneaded under the conditions of an extrusion temperature of 240 ° C. and a screw rotation speed of 200 rpm, and extruded into a strand shape. The strand-shaped kneaded product was cooled and then pelletized with a pelletizer.

Similarly, the content of each material with respect to the total mass of the resin composition constituting the B layer is blended at a predetermined ratio according to the molding number so as to have the value shown in Table 1, and φ30 mm different direction rotation biaxial extrusion. Using a machine (KTX-30, manufactured by Kobe Steel, Ltd.), the mixture was melt-kneaded under the conditions of an extrusion temperature of 240 ° C. and a screw rotation speed of 200 rpm, and extruded into a strand shape. The strand-shaped kneaded product was cooled and then pelletized with a pelletizer.

The pellets for layer A and the pellets for layer B prepared above are used in a feed block type T-die multi-layer extruder with two φ40 mm short shaft extruders, a feed block at the tip, and a T-die with a lip width of 550 mm. The two-kind two-layer coextrusion molding was carried out to obtain various sheet-shaped molded bodies in which the A layer and the B layer were laminated with the thickness shown in Table 1. The extrusion of the A layer and the B layer was carried out under the conditions of an extrusion temperature of 240 ° C. and a T die temperature of 240 ° C. The temperature of the pinch roll closest to the die of the take-up device was set to 30 ° C. As the pinch roll, a mirror-finished one or an embossed one was used according to the number of the molding example.

<Molding Examples 27 to 30: Thermoplastic Resin Sheet>
PVC1: A commercially available colorless and transparent polyvinyl chloride sheet having various thicknesses shown in Table 2, trade name Emron (color: Tome, surface finish: gloss) manufactured by Morino Kako Co., Ltd. was prepared and used as it was.

<Molding example 31: Thermoplastic resin sheet>
PET1: A commercially available colorless and transparent polyethylene terephthalate resin sheet that has been biaxially stretched and has the thickness shown in Table 2 and has acrylic primers on both sides. I prepared it and used it as it was.

<Molding example 32: Thermoplastic resin sheet>
PA1: A commercially available polyamide 6 resin pellet, trade name Amylan CM1007 manufactured by Toray Industries, Inc. was prepared and molded into a sheet by a heat press molding method. Specifically, the polyamide 6 resin pellets are preheated under the condition of 280 ° C. for 10 minutes, press-molded at a pressure of 5 MPa, held under pressure for 2 minutes at the same pressure to relax the orientation, and then rapidly cooled. As a result, a colorless and transparent polyamide resin sheet having the thickness shown in Table 2 and in a non-oriented state was molded. Both surfaces of this polyamide-based resin sheet were subjected to corona discharge treatment and used for evaluation.

<Molding example 33: Thermoplastic resin sheet>
PC1: A commercially available colorless and transparent polycarbonate resin sheet having the thickness shown in Table 2, trade name Iupiron Film FE-2000 manufactured by Mitsubishi Gas Chemical Company, was prepared and used as it was.

<Molding Examples 34 to 36: Thermoplastic Resin Sheet>
A T-die having a lip width of 550 mm was attached to the tip of a φ40 mm short shaft extruder, and single-layer extrusion molding was performed on the acrylic 1 described above to form single-layer sheets of various thicknesses shown in Table 2. The extrusion temperature was 240 ° C., the T-die temperature was 240 ° C., and the cooling roll temperature was 30 ° C. As the pinch roll, a mirror-finished rubber roll was used.

<Molding example 37: Thermoplastic resin sheet>
Acrylic 2: As a poly (meth) acrylic acid ester resin, Sumitomo Chemical's trade name Sumipex MGSS (polymethylmethacrylate, MFR (ISO1133 compliant, 230 ° C., 3.8 kg load): 11 g / 10 minutes) was prepared. ..
A T-die with a lip width of 550 mm is attached to the tip of a φ40 mm short shaft extruder, and single-layer extrusion molding is performed on the acrylic 2 described above to prepare a colorless and transparent sheet-shaped molded product having the thickness shown in Table 2. did. The extrusion temperature was 210 ° C., the T-die temperature was 210 ° C., and the pinch roll temperature was 30 ° C. As the pinch roll, a mirror-finished rubber roll was used.

<Molding example 38: Thermoplastic resin sheet>
PS1: As a polystyrene-based resin, Toyo Styrene GP G200C (polystyrene, MFR (ISO1133 compliant, 200 ° C., 5.0 kg load): 9 g / 10 minutes) was prepared.
A T-die having a lip width of 550 mm was attached to the tip of a φ40 mm short shaft extruder, and single-layer extrusion molding was performed on PS1 described above to prepare a colorless and transparent sheet-shaped molded product having the thickness shown in Table 2. .. The extrusion temperature was 210 ° C., the T-die temperature was 210 ° C., and the pinch roll temperature was 30 ° C. As the pinch roll, a mirror-finished rubber roll was used.

(2. Preparation of adhesive)
Adhesive 1: The isocyanate-based cross-linking agent shown in Table 3 was blended with 100 parts by mass of the acrylic pressure-sensitive adhesive shown in Table 3 by the mass part shown in Table 3 to prepare a pressure-sensitive adhesive 1.

(3. Preparation of vacuum forming sheet)
<Examples 1-33, Comparative Examples 1-2: No adhesive used>
Using the sheets produced in the above molding examples, various vacuum forming sheets of Examples and Comparative Examples having the laminated structure shown in Table 4 were produced. Specifically, the fluorine-based resin sheet and the thermoplastic resin sheet shown in Table 4 are heat-laminated (heat-sealed) at 160 ° C., and vacuum forming with the A layer, the B layer, and the thermoplastic resin layer in this order. Sheet was prepared. When the vacuum forming sheet was produced, the sheets whose MD (winding direction of the sheet roll) was known were laminated so that the MD directions were matched.

<Examples 34 to 37, Comparative Example 3: Adhesive used>
Using the sheet prepared in the above molding example, the main surface on the side to which the pressure-sensitive adhesive 1 was applied (layer B for the two-layer sheet) was subjected to corona discharge treatment. Next, the pressure-sensitive adhesive 1 was applied to a release paper (SLB-50BD, manufactured by Sumika Kako Paper Co., Ltd.) so that the thickness after drying was 50 μm, dried, and laminated by adhering to the main surface of the sheet. Next, the release paper was peeled off, the thermoplastic resin sheet shown in Table 4 was attached to the layer of the pressure-sensitive adhesive 1 according to the test number, and the mixture was allowed to stand in an environment of 23 ° C. for 24 hours. From this, a vacuum forming sheet having a fluorine-based resin layer, an adhesive layer, and a thermoplastic resin layer in this order was produced. When the vacuum forming sheet was produced, the sheets whose MD (winding direction of the sheet roll) was known were laminated so that the MD directions were matched.

<Reference Examples 2-4>
The sheet shown in Table 4 produced in the above molding example was used as it was as a vacuum forming sheet.

(4. Adhesiveness test)
For each of the above vacuum forming sheets, the adhesive strength between the fluororesin layer and the thermoplastic resin layer was peeled off and adhered according to JIS Z0237-2009 using a tensile tester and Strograph VE1D manufactured by Toyo Seiki Seisakusho. Force measurement, method 1; 180 ° peeling off to the test plate The measurement was performed according to the method for measuring the adhesive strength. At this time, if the peeling adhesive strength was strong and the material was destroyed before the peeling, it was displayed as> 20.0 N / 25 mm. The results are shown in Table 4.

Specifically, first, the fluorine-based resin layer / thermoplastic resin layer of each vacuum forming sheet is peeled by 25 mm, and each vacuum forming sheet is cut into a width of 25 mm in a direction orthogonal to the peeling direction to have a width of 25 mm. A sample for measurement was prepared. Next, the measurement sample was fixed to a stainless steel plate, the peeling force was measured at 180 ° at a peeling speed of 300 mm / min, and the average peeling force between 25 to 75 mm was the adhesive strength between the fluororesin layer / thermoplastic resin layer (N). / 25 mm). When MD / TD can be distinguished, the average peeling force of each MD / TD was calculated and the average value was used. When MD / TD could not be distinguished, the average peeling force in any direction was calculated and used. The adhesive strength between the fluororesin layer / thermoplastic resin layer was preferably 10 N / 25 mm or more. If it is less than 10 N / 25 mm, when the vacuum forming sheet is vacuum formed, it may be peeled off (delaminated) at the interface between the fluororesin layer / the thermoplastic resin layer, resulting in a defective product. There is concern that the price will decline. The adhesive strength between the fluororesin layer / thermoplastic resin layer is more preferably 12 N / 25 mm or more, further preferably 13 N / 25 mm or more, and particularly preferably 15 N / 25 mm or more.

(5. Evaluation of vacuum formability)
For each of the above vacuum forming sheets, the storage elastic modulus at 140 ° C. (E'(140 ° C.) value) and the storage elastic modulus at 110 ° C. (E'(110 ° C.) value) are set to TA Instruments. Using the viscoelasticity measuring device RSA-G2 manufactured by the company, the tensile mode, frequency 1.0 Hz, temperature rise rate 4 ° C / min, measurement temperature range 30 to 180 ° C, and MD if the measurement direction can be specified. If it could not be done, it was obtained by dynamic viscoelasticity measurement in any direction, and ((E'(140 ° C.)) value / (E'(110 ° C.)) value) was calculated. The results are shown in Table 4.

In addition, for each vacuum forming sheet, a bolt / nut cap mold (male mold) with a depth of 46 mm is set using a pressure air vacuum forming machine for research and development manufactured by Asano Laboratories Co., Ltd., and the surface temperature of the sheet is 125. By vacuum forming at ° C. using the plug assist method, the shape of the bolt / nut cap as shown in FIG. 3a was vacuum formed. Then, using a Toko hydraulic clicker TCM-450A manufactured by Toko Co., Ltd., unnecessary parts were trimmed to obtain a vacuum-formed product having a bolt-nut cap shape as shown in FIG. 3a. Vacuum forming is performed 20 times under the same conditions, and the defective product is regarded as a defective product if the vacuum-formed product has holes or if peeling (delamination) occurs at the interface between the fluororesin layer / thermoplastic resin layer. Was measured. The results are shown in Table 4.

(6. Evaluation of corrosion resistance)
Use a colorless and transparent two-component mixed acrylic adhesive (manufactured by Denka Co., Ltd., trade name: Bolt Lock 10) to vacuum-form the collar of a vacuum-formed product in the shape of a bolt / nut cap under the same conditions as before. Adhered to the surface of ordinary steel. Bolts and nut caps were installed on both the bolt side and the nut side. After the adhesive had dried, a salt spray test in accordance with JIS Z2371: 2015 was performed. A salt spray tester STP-110 manufactured by Suga Test Instruments Co., Ltd. was used, and the test conditions were as follows. Since a colorless and transparent adhesive was used, the transparency of the bolt / nut cap collar was not impaired.
<Salt spray test conditions>
Spray room temperature: 35 ± 2 ° C
Salt water concentration: 5 ± 1% (about 50 g / L)
Test time: 500 hours Post-test treatment: Wash with pure water and dry

After the test was completed, the area of the circular steel surface inside the collar was visually confirmed to be corroded, and the corrosion area ratio was determined. The results are shown in Table 4.

<Reference example 1>
The above salt spray was performed on the surface of ordinary steel. After that, the same appearance check as above was performed. The results are shown in Table 4.

(7. Evaluation of antifouling property)
Public Works Research Center Antifouling Material Evaluation Promotion Test In accordance with Antifouling Material Evaluation Promotion Test Method III, the brightness difference (ΔL ^* ) before and after the test of each of the above vacuum forming sheets was measured, and ^{the brightness difference (ΔL *) was measured.} ) Was used as an index of antifouling property (| ΔL ^{* |).} The brightness of each vacuum forming sheet was measured from the A layer side for the two-layer sheet. The suspension was prepared by the specified material and method, and the pretreatment of the test piece was performed by the specified method. The brightness difference (ΔL ^* ) was calculated based on the following formula using a color meter ZE6000 manufactured by Nippon Denshoku Kogyo Co., Ltd. The antifouling property was evaluated using the absolute value (| ΔL ^* |) of the obtained brightness difference (ΔL ^{*) as an index.} The larger the absolute value (| ΔL ^{* |) of the brightness difference (ΔL *} ) before and after the test, the more dirty it is. The absolute value (| ΔL ^* |) judged to have good antifouling property is 3.2 or less according to the criteria of the antifouling material evaluation promotion test method III, but at the time of evaluation in this example, 2. Even when it was 0 or more, it was judged that it was clearly contaminated visually, so less than 2.0 was preferable as a stricter standard. The absolute value (| ΔL ^* |) is more preferably 1.5 or less, further preferably 1.3 or less, and particularly preferably 1.2 or less. The results are shown in Table 4.
Brightness difference (ΔL ^* ) = (average brightness L ₁ ^* after test)-(average brightness L ₀ ^* before test)

<Reference example 1>
The same antifouling property evaluation as above was carried out on the surface of ordinary steel. The results are shown in Table 4.

(8. Weather resistance test)
The glossiness of each of the above vacuum forming sheets cut into a rectangular shape of 50 mm × 50 mm was measured using a 60 ° gloss meter, and the reference color was measured using a colorimetric color difference meter. Next, using a metal halide lamp type ultra-accelerated weathering tester Eye Super UV Tester SUV-W161 (manufactured by Iwasaki Electric Co., Ltd.), UV irradiation intensity 1,320 w / m ² , humidity 50%, black panel temperature 63 ° C, UV irradiation. Conditions: Irradiation in 6 cycles of 2-minute shower and 8-minute rest is 1 hour, darkness without shower is 0.5 hours, total 1.5 hours is 1 cycle, and weather resistance test is performed under the condition of test time 525 hours. went. After the weather resistance test, the glossiness of each vacuum forming sheet was measured using a 60 ° gloss meter, and the b ^* difference (Δb ^* ) from the reference color was measured using a colorimetric color difference meter. Table 4 shows the gloss retention rate, which is the ratio of the glossiness after the weathering test to the glossiness before the weathering test. Table 4 shows the ^{b *} difference (Δb ^* ) as an index of yellowing after the weather resistance test compared to before the weather resistance test. As for the glossiness, micro-glass 60 ° manufactured by BYK-Gardner was used, and the 60 ° mirror surface gloss was measured in accordance with JIS Z8741: 1997. The b ^* difference (Δb ^* ) was measured using a colorimetric color difference meter and color meter ZE6000 manufactured by Nippon Denshoku Kogyo Co., Ltd. in accordance with JIS Z8730: 2009, and b ^* value measurements were performed before and after the test. The b ^* difference (Δb ^* ) was calculated. The b ^* difference (Δb ^* ) was preferably 5.0 or less. When the b ^* difference (Δb ^* ) exceeds 5.0, it can be visually determined that the color is yellowed. The b ^* difference (Δb ^* ) is more preferably 3.0 or less, further preferably 2.5 or less, and particularly preferably 2.2 or less.
Formula: b ^* difference (Δb ^* ) = (b ^* value after accelerated weathering test)-(initial b ^* value)

(9. Evaluation of transparency)
(1) Total light transmittance Haze meter NDH7000 (manufactured by Nippon Denshoku Kogyo Co., Ltd.) was used to determine the total light transmittance of each of the above vacuum forming sheets in accordance with JIS K7361-1-1997. The results are shown in Table 4.
(2) HAZE
The HAZE value of each of the above vacuum forming sheets was measured using a haze meter NDH7000 (manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with JIS K7136-2000. The results are shown in Table 4.

<Discussion>
The molding sheet according to any of the examples was excellent in adhesiveness, vacuum formability, corrosion resistance, stain resistance, weather resistance, and transparency. On the other hand, the bolt / nut cap according to the comparative example did not obtain satisfactory characteristics in at least one of these characteristics. A detailed consideration is added below.

From Examples 1 to 4 and Comparative Example 1, when the polyvinylidene fluoride-based resin of the A layer exceeds 50% by mass and the poly (meth) acrylic acid ester-based resin exceeds 50% by mass, the antifouling property and weather resistance are improved. It can be seen that it has decreased.

From Examples 3, 5 to 9, and Comparative Example 2, when the polyvinylidene fluoride-based resin of the B layer exceeds 50% by mass and the poly (meth) acrylic acid ester-based resin is less than 50% by mass, the adhesiveness and vacuum forming are performed. It can be seen that the sex and anticorrosion properties have decreased. In particular, in Comparative Example 2, the (E'(140 ° C.)) value / (E'(110 ° C.)) value was appropriate, and although the vacuum formability was good, the adhesiveness was low. When the molded product after molding is trimmed, the fluororesin layer of the molded product is likely to be peeled off and a vacuum is likely to occur.

From Examples 2 and 10 to 17, it can be seen that the weather resistance was improved by blending the UV absorber in the B layer.

From Examples 2 and 17, it can be seen that the desired physical properties were exhibited even when the type of UV absorber used was changed.

From Examples 2 and 18, it can be seen that the total light transmittance is maintained without impairing the physical properties other than HAZE by embossing with the embossing roll at the time of manufacturing the A layer / B layer laminate. From this, it can be seen that it can also be used as a matte film.

From Examples 2 and 19 to 23, it can be seen that the desired physical properties were exhibited even when the thickness of the A layer / B layer laminate was changed.

From Examples 20 and 25 to 33, if the (E'(140 ° C.)) value / (E'(110 ° C.)) value is appropriate, the physical properties are exhibited without being affected by the material and thickness of the thermoplastic resin layer. You can see that.

It can be seen from Examples 20, 25 to 27, and 30 to 32 that the thicker the thermoplastic resin layer is, the less likely it is that holes are formed during vacuum forming, and the rate of defective products due to the improvement in vacuum forming is reduced. ..

From Examples 2 and 34, it can be seen that even if the pressure-sensitive adhesive layer is formed between the fluororesin layer and the thermoplastic resin layer, the physical properties are exhibited without being affected by the pressure-sensitive adhesive layer.

From Examples 34 to 37 and Comparative Example 3, the storage elastic modulus (E'(140 ° C.) value) at 140 ° C. obtained by the dynamic viscoelasticity measurement of the molding sheet is changed to the storage elastic modulus (E'(110 ° C.)) at 110 ° C. When the value ((E'(140 ° C.)) value / (E'(110 ° C.)) value) divided by (° C.) value) is less than 0.1, it can be seen that the vacuum formability has deteriorated. The fact that ((E'(140 ° C.)) value / (E'(110 ° C.)) value) exceeds 1 means that the material of the resin constituting the laminated sheet is not thermoplastic but thermosetting. Therefore, it basically does not exceed 1.

Since the heat-molding sheet of the present invention is excellent in rust-proof, corrosion-proof, and stain-proof properties, it is heat-molded into a bolt / nut cap and coated on bolts and / or nuts used in various structures. Therefore, it can be widely used for repair work, reinforcement work, post-maintenance, and deterioration repair work of structures that have deteriorated over time.
Further, the thermoforming sheet of the present invention is thermoformed into a bolt and nut cap, and the bolts and / or nuts used for new construction and various structures before aging deterioration are coated to deteriorate the structure. It can be widely used for preventive maintenance such as progress prevention work and deterioration progress prevention work.
Further, the transparent bolt / nut cap can be widely used for deterioration prediction maintenance work because the deterioration of the bolt and / or the nut can be visually confirmed.
Further, the thermoforming sheet of the present invention can be used for applications such as decorative boards and automobile decorations by utilizing its excellent thermoforming properties.

100 Thermoforming sheet 110 Fluorine-based resin layer 110a A layer 110b B layer 120 Adhesive layer 130 Thermoplastic resin layers 300a, 300b, 300c, 300d, 300e, 300f Bolt nut caps 301a, 301b Outer surfaces 302a, 302b Surface 310a, 310b Main body 310a1 First step 310a2 Second step 310a3 Third step 320a, 320b Border 330a, 330b Opening 400 Steel 410 Steel surface 410a Member corner (edge surface)
410b, 410c Flat surface 410d Ridge 430 Bolt hole 500 Bolt and nut protrusion 500a Washer 500b Nut 500c Bolt tip 600 Bolt head 600a Washer 700 Adhesive 800 Anticorrosion sheet

Claims (14)

A thermoforming sheet provided with at least the following A layer and B layer and a thermoplastic resin layer in this order, and has a storage elastic modulus (E'(E'(E'(E')" at 140 ° C. obtained by dynamic viscoelasticity measurement of the thermoforming sheet. The value ((140 ° C.) value) divided by the storage elastic modulus (E'(110 ° C.) value) at 110 ° C. ((E'(140 ° C.)) value / (E'(110 ° C.)) value) is 0.1. A thermoforming sheet of ~ 1.0.
Layer A: Resin composition containing 50 parts by mass or more and 100 parts by mass or less of a polyvinylidene fluoride resin and 0 parts by mass or more and 50 parts by mass or less of a poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things.
Layer B: Resin composition containing 0 parts by mass or more and less than 50 parts by mass of polyvinylidene fluoride resin and more than 50 parts by mass and 100 parts by mass or less of poly (meth) acrylic acid ester resin (the total of both is 100 parts by mass). A layer of things. The thermoforming sheet according to claim 1, wherein the resin composition constituting the B layer contains 0.05 to 15 parts by mass of an ultraviolet absorber. The thermoforming sheet according to claim 1 or 2, wherein the total light transmittance measured according to the measuring method specified in JIS K7361-1-1997 is 75% or more. The thermoforming sheet according to any one of claims 1 to 3, wherein the HAZE measured according to the measuring method specified in JIS K7136-2000 is 60% or less. The thermoplastic resin layer contains one or more selected from the group consisting of poly (meth) acrylic acid ester-based resin, polyvinyl chloride-based resin, polycarbonate-based resin, polyethylene terephthalate-based resin, and polyamide-based resin. , The heat-molding sheet according to any one of claims 1 to 4. The thermoforming sheet according to any one of claims 1 to 5, which has a thickness of 200 to 2,000 μm. The thermoforming sheet according to any one of claims 1 to 6, wherein the total thickness of the A layer and the B layer is 10 to 300 μm, and the thickness of the thermoplastic resin layer is 100 to 1,990 μm. A thermoformed product obtained by thermoforming the thermoforming sheet according to any one of claims 1 to 7. The thermoformed product according to claim 8, which is a bolt / nut cap provided with at least the A layer, the B layer, and the thermoplastic resin layer in this order from the outside to the inside. A method for protecting or repairing one or both of bolts and nuts, which comprises fixing the thermoformed product according to claim 9 so as to cover the protrusions of one or both of the bolts and nuts using an adhesive. A method for protecting or repairing a steel structure including a steel material and bolts and nuts fixed to the steel material, wherein a thermoformed product according to claim 8 or 9 is used for bolts and nuts by using an adhesive. A step of fixing to the surface of the steel material so as to cover one or both protrusions, and
The process of attaching the anticorrosion sheet to the surface of the steel material and
Protection or repair methods including. The protection or repair method according to claim 10 or 11, wherein the adhesive is a colorless and transparent acrylic adhesive. A steel structure comprising the thermoformed product according to claim 8, a steel material, and bolts and nuts fixed to the steel material, wherein the thermoformed product has protrusions of one or both of the bolts and nuts. A steel structure fixed to the surface of the steel material so as to cover the steel material. A steel structure protected or repaired using the protection or repair method according to claim 11.