Peelable adhesive layer and laminate

Abstract

To provide a peelable adhesive layer with good adhesion that does not peel off during normal use, and good release properties that allow it to be peeled off when you want to.SOLUTION: There is provided a peelable adhesive layer. The peelable adhesive layer is a coating film of a coating material for an adhesive layer. The coating material for an adhesive layer is a two-part type coating material consisting of a first agent containing a water-dispersed acrylic resin and a water-dispersed urethane resin, and a second agent containing isocyanate. The water-dispersed urethane resin has a glass transition temperature (Tg) of -80 to 0°C. The water-dispersed acrylic resin has a hydroxy value of 40 to 165 mg KOH / g. The ratio (NCO / OH) of the number of moles of isocyanate groups in the isocyanate to the number of moles of hydroxy groups contained in the first agent is 0.5 to 2.0.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a peelable adhesive layer and a laminate. [Background technology]

[0002] A removable coating film may be applied to the exterior of an automobile (e.g., a clear coating film on the exterior of an automobile) for the purpose of changing the color or protecting the exterior of the automobile. Such a coating film is peeled off after being used for a certain period of time. High coating film performance is required for the exterior of the automobile during the period of use. Paints for removable coating films are widely available, for example, those in which synthetic rubber such as styrene-butadiene copolymer is dissolved in organic solvents such as xylene, ethylbenzene, acetone, and methyl ethyl ketone. These paints emit volatile organic compounds into the air during the drying process, raising health and environmental concerns. In recent years, against this background, there has been a demand for water-based paints for removable coating films (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2020 / 0216682 Summary of the Invention [Problem to be solved by the invention]

[0004] Such coating films must maintain an appropriate adhesion from the time of application until the time of final peeling so that they do not peel off accidentally and can be peeled off when desired.

[0005] When the present inventors attempted to apply a conventional water-based one-component paint to the exterior of an automobile, the following problems arose. 1. Adhesion that does not peel off during normal use Second: Peelability so you can peel it off whenever you want

[0006] The peelability allows the film to be peeled off whenever desired, but even if the adhesion or peelability is adequate at the beginning of the coating film creation, the adhesion gradually increases due to heat (for example, summer temperatures), and the peelability does not last.

[0007] Therefore, an object of the present invention is to provide a peelable adhesive layer that has sufficient adhesion so that it does not peel off during normal use and sufficient releasability so that it can be peeled off whenever desired, and to provide a laminate that includes such a peelable adhesive layer. [Means for solving the problem]

[0008] The peelable adhesive layer according to the present invention comprises: It is a coating film of paint for adhesive layer, the adhesive layer coating material is a two-component type consisting of a first agent containing a water-dispersible acrylic resin and a water-dispersible urethane resin, and a second agent containing an isocyanate; The water-dispersible urethane resin has a glass transition temperature (Tg) of −80 to 0° C., the hydroxyl value of the water-dispersible acrylic resin is 40 to 165 mg KOH / g, The ratio (NCO / OH) of the number of moles of isocyanate groups in the isocyanate to the number of moles of hydroxyl groups in the first agent is 0.5 to 2.0, which provides a peelable adhesive layer with sufficient adhesion to prevent peeling during normal use and excellent releasability to allow peeling at any desired time.

[0009] The laminate according to the present invention comprises: The peelable adhesive layer; This provides a laminate that has good adhesion so that it will not peel off during normal use and good releasability so that it can be peeled off whenever desired.

[0010] In one embodiment of the laminate according to the present invention, the proportion of the mass of the water-dispersed acrylic resin to the total mass of the water-dispersed acrylic resin and the water-dispersed urethane resin is 10 to 90 mass %.

[0011] In one embodiment of the laminate according to the present invention, the laminate is for use in a one-component coating film containing a polymerizable unsaturated monomer having an acid anhydride group, or a two-component coating film containing a urethane resin.

[0012] In one embodiment of the laminate according to the present invention, the peel strength is 3N or more.

[0013] In one embodiment of the laminate according to the present invention, the peel strength after 80° C. / 100 hours is 10 N or less.

[0014] In one embodiment of the laminate according to the present invention, the peel strength after an Xe test of 750 MJ is 10 N or less.

[0015] In one embodiment of the laminate according to the present invention, The peelable adhesive layer; A design layer and and the clear layer. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a peelable adhesive layer that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. Also, according to the present invention, it is possible to provide a laminate that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram showing an example of a peelable adhesive layer according to the present invention. [Figure 2] FIG. 2 is a schematic diagram showing an example of the layer structure of the laminate according to the present invention. [Figure 3] FIG. 3 is a schematic diagram showing another example of the layer structure of the laminate according to the present invention. [Figure 4] FIG. 4 is a schematic diagram showing another example of the layer structure of the laminate according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described. These descriptions are for the purpose of illustrating the present invention and are not intended to limit the present invention in any way.

[0019] In the present invention, two or more embodiments can be combined in any manner.

[0020] In the present invention, the paint and the paint composition can be used interchangeably.

[0021] Unless otherwise specified, numerical ranges are intended to include the upper and lower limits of the range. For example, -80 to 0°C means a range from -80°C to 0°C.

[0022] The accompanying drawings are schematic diagrams given priority for facilitating understanding of the present invention, and therefore the dimensions and scale of each element in the drawings are not accurate.

[0023] In the present invention, the peel strength, the peel strength after 80° C. / 100 hours, and the peel strength after an Xe test of 750 MJ are measured by the methods described in the examples.

[0024] In the present invention, the resins, solvents, compounds, materials, members, etc. may each be used alone or in combination of two or more.

[0025] (peelable adhesive layer) The peelable adhesive layer according to the present invention comprises: It is a coating film of paint for adhesive layer, the adhesive layer coating material is a two-component type consisting of a first agent containing a water-dispersible acrylic resin and a water-dispersible urethane resin, and a second agent containing an isocyanate; The water-dispersible urethane resin has a glass transition temperature (Tg) of −80 to 0° C., the hydroxyl value of the water-dispersible acrylic resin is 40 to 165 mg KOH / g, In the peelable adhesive layer, the ratio (NCO / OH) of the number of moles of isocyanate groups in the isocyanate to the number of moles of hydroxyl groups contained in the first agent is 0.5 to 2.0.

[0026] FIG. 1 is a schematic diagram showing an example of a peelable adhesive layer according to the present invention.

[0027] The peelable adhesive layer is a coating film of a paint for an adhesive layer, and is usually provided in contact with the exterior of the automobile. After use of the laminate of the present invention, the peelable adhesive layer is peeled off from the exterior of the automobile, thereby peeling the laminate of the present invention from the exterior of the automobile.

[0028] ·Adhesive layer paint The adhesive layer paint that forms the peelable adhesive layer is a two-component type consisting of a first agent and a second agent.

[0029] First agent The first agent contains a water-dispersible acrylic resin and a water-dispersible urethane resin.

[0030] The water-dispersible acrylic resin can be obtained, for example, by solution polymerization of a mixture of polymerizable unsaturated monomers, such as (meth)acrylic acid alkyl esters, carboxyl group-containing ethylenically unsaturated monomers, and hydroxyl group-containing ethylenically unsaturated monomers.

[0031] Examples of (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate.

[0032] Examples of carboxyl group-containing ethylenically unsaturated monomers include acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, ethacrylic acid, propylacrylic acid, isopropylacrylic acid, itaconic acid, maleic anhydride, and fumaric acid.

[0033] Examples of hydroxyl group-containing ethylenically unsaturated monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, N-methylolacrylamide, allyl alcohol, and ε-caprolactone-modified acrylic monomers.

[0034] The acrylic resin prepared by polymerization may be neutralized with, for example, a basic compound and used in the form of an aqueous solution.

[0035] Examples of basic compounds include organic amines such as monomethylamine, dimethylamine, trimethylamine, triethylamine, diisopropylamine, monoethanolamine, diethanolamine, and dimethylethanolamine.

[0036] The water-dispersible acrylic resin has a hydroxyl value of 40 to 165 mg KOH / g. In one embodiment, the water-dispersible acrylic resin has a hydroxyl value (mg KOH / g) of 40 or more, 50 or more, 60 or more, 70 or more, 80 or more, 90 or more, 100 or more, 110 or more, 120 or more, 130 or more, 140 or more, 150 or more, or 160 or more. In another embodiment, the water-dispersible acrylic resin has a hydroxyl value (mg KOH / g) of 165 or less, 160 or less, 150 or less, 140 or less, 130 or less, 120 or less, 110 or less, 100 or less, 90 or less, 80 or less, 70 or less, 60 or less, or 50 or less. In yet another embodiment, the water-dispersible acrylic resin has a hydroxyl value (mg KOH / g) of 40 to 130.

[0037] The amount of water-dispersed acrylic resin in the first agent may be adjusted as appropriate. In one embodiment, the mass ratio of the water-dispersed acrylic resin to the total mass of the water-dispersed acrylic resin and the water-dispersed urethane resin is 10 to 90% by mass. In another embodiment, the mass ratio of the water-dispersed acrylic resin to the total mass of the water-dispersed acrylic resin and the water-dispersed urethane resin is 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more. In yet another embodiment, the mass ratio of the water-dispersed acrylic resin to the total mass of the water-dispersed acrylic resin and the water-dispersed urethane resin is 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, or 20% by mass or less.

[0038] As the water-dispersible acrylic resin, a commercially available product may be used.

[0039] The water-dispersible urethane resin is preferably a reaction product of a polyol and a polyisocyanate, and may be a reaction product obtained by further reacting a chain extender or a terminal terminator with the reaction product of a polyol and a polyisocyanate.

[0040] Examples of the polyol include polyether polyol, polyester polyol, polycarbonate polyol, polybutadiene polyol, and polythioether polyol.

[0041] Examples of polyether polyols include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

[0042] Examples of polyester polyols include reaction products of polycarboxylic acids with polyester raw material polyols, ring-opening polymerization products of ε-caprolactone, copolymers thereof, etc. Examples of the polycarboxylic acids include adipic acid, sebacic acid, itaconic acid, maleic anhydride, phthalic acid, isophthalic acid, etc. Examples of the polyester raw material polyols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, tripropylene glycol, butylene glycol, neopentyl glycol, etc.

[0043] Polycarbonate diol can be prepared, for example, by reacting a polyhydric alcohol (such as a diol) with dimethyl carbonate.

[0044] Examples of polyhydric alcohols include diols, such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-2,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2,4-pentanediol, 2,4-diethyl-1,5-pentanediol, and 1,6-hexanediol.

[0045] Examples of polyisocyanates include ethylene diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, cyclohexane-1,4-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, p-xylylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate, and 1,5-naphthylene diisocyanate.

[0046] Examples of the chain extender include ethylene glycol, propylene glycol, 1,4-butanediol, pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, diethylene glycol, glycerin, and trimethylolpropane.

[0047] Examples of the end terminator include monoalcohols such as methanol, butanol, octanol, and alkyl alcohol alkylene oxide adducts; and monoamines such as butylamine and dibutylamine.

[0048] The Tg of the water-dispersible urethane resin is −80° C. to 0° C. In one embodiment, the Tg of the water-dispersible urethane resin is −80° C. or higher, −70° C. or higher, −60° C. or higher, −50° C. or higher, −40° C. or higher, −30° C. or higher, −20° C. or higher, or −10° C. or higher. In another embodiment, the Tg of the water-dispersible urethane resin is 0° C. or lower, −10° C. or lower, −20° C. or lower, −30° C. or lower, −40° C. or lower, −50° C. or lower, −60° C. or lower, or −70° C. or lower.

[0049] As the water-dispersible urethane resin, a commercially available product may be used.

[0050] The first agent may contain other resins in addition to the water-dispersible acrylic resin and water-dispersible urethane resin. Examples include polyester resin, polyolefin resin, alkyd resin, epoxy resin, SBR, and NBR. Other components may also include pigments, dispersants, antifoaming agents, UV absorbers, hindered amine light stabilizers, antioxidants, viscosity modifiers, surface conditioners, film-forming aids, rust inhibitors, thickeners, organic solvents, and curing catalysts.

[0051] The laminate according to the present invention is for use in, for example, a one-component coating film containing a polymerizable unsaturated monomer having an acid anhydride group, or a two-component coating film containing a urethane resin.

[0052] Examples of polymerizable unsaturated monomers having an acid anhydride group include maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, phthalic anhydride, oxydiphthalic anhydride, naphthalenedicarboxylic anhydride, trimellitic anhydride, and pyromellitic anhydride.

[0053] Second agent The second agent contains an isocyanate, such as an aliphatic isocyanate, an aliphatic cyclic isocyanate, an alicyclic isocyanate, an aromatic isocyanate, and biuret and nurate derivatives thereof.

[0054] Examples of the aliphatic isocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (HDI), and trimethylhexamethylene diisocyanate.

[0055] Examples of the aliphatic cyclic isocyanate include 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, and 1,2-cyclohexane diisocyanate.

[0056] Examples of alicyclic isocyanates include isophorone diisocyanate (IPDI) and norbornane diisocyanate methyl.

[0057] Examples of aromatic isocyanates include xylylene diisocyanate (XDI), 2,4-tolylene diisocyanate (TDI), and 2,6-tolylene diisocyanate.

[0058] The ratio (NCO / OH) of the number of moles of isocyanate groups in the isocyanate to the number of moles of hydroxyl groups in the first agent (e.g., hydroxyl groups in the water-dispersible acrylic resin) is 0.5 to 2.0. In one embodiment, the ratio (NCO / OH) is 0.5 or more, 0.6 or more, 0.8 or more, 1.0 or more, 1.2 or more, 1.4 or more, 1.6 or more, or 1.8 or more. In another embodiment, the ratio (NCO / OH) is 2.0 or less, 1.8 or less, 1.6 or less, 1.4 or less, 1.2 or less, 1.0 or less, 0.8 or less, or 0.6 or less.

[0059] The thickness of the peelable adhesive layer may be adjusted appropriately, but is, for example, 20 to 100 μm.

[0060] Method for preparing coating material for peelable adhesive layer For example, a water-dispersible acrylic resin and a water-dispersible urethane resin are mixed to prepare a first agent. A second agent containing a polyisocyanate is prepared separately. An organic solvent without a hydroxyl group may be optionally mixed into the second agent. The resulting first and second agents are mixed to prepare a coating material for a peelable adhesive layer. Typically, the first and second agents are mixed immediately before the coating material for a peelable adhesive layer is applied.

[0061] Formation of peelable adhesive layer The method for forming the peelable adhesive layer is not particularly limited, and for example, a paint for a peelable adhesive layer is applied to an article to be coated, and the coating film is cured to form the peelable adhesive layer.

[0062] The amount of coating material for the peelable adhesive layer to be applied is not particularly limited and may be set appropriately depending on the performance required of the coating film. For example, the coating is applied so that the thickness of the dried coating film is 20 to 100 μm.

[0063] The coating method for the peelable adhesive layer paint is not particularly limited, and examples thereof include air spray coating, airless spray coating, rotary atomization coating, curtain coating, etc. These methods may be combined with electrostatic coating. Coating may be performed multiple times.

[0064] After applying the coating material for the peelable adhesive layer, the coating film is cured. The curing conditions can be set appropriately depending on the amount applied and the composition, for example, at 60°C for about 20 minutes.

[0065] (Laminate) The laminate according to the present invention comprises: The peelable adhesive layer; and a clear layer or a design layer.

[0066] Fig. 2 is a schematic diagram showing an example of the layer structure of the laminate according to the present invention. The laminate 10 in Fig. 2 is composed of a peelable adhesive layer 1 and a clear layer 2, in that order.

[0067] Fig. 3 is a schematic diagram showing another example of the layer structure of the laminate according to the present invention. The laminate 10 in Fig. 2 is made up of a peelable adhesive layer 1 and a design layer 3, in that order.

[0068] Fig. 4 is a schematic diagram showing another example of the layer structure of the laminate according to the present invention. The laminate 10 in Fig. 2 is composed of a peelable adhesive layer 1, a design layer 3, and a clear layer 2, in that order.

[0069] Clear layer The clear layer is a coating film of a coating composition for a clear layer, and serves to protect the layers located on the vehicle body side of the laminate, such as the peelable adhesive layer and any design layer. The clear layer is usually provided as the outermost layer of the laminate.

[0070] The clear layer coating composition can be a known clear coating composition. The clear layer coating composition can be, for example, the clear coating composition described in International Publication No. 2020 / 241342 and Japanese Patent No. 7052119. In addition, automotive repair paints described in JP-A-2022-180115 can also be used.

[0071] The coating composition for the clear layer may be either water-based or solvent-based.

[0072] The thickness of the clear layer may be adjusted appropriately, and is, for example, 20 to 100 μm.

[0073] Design layer The decorative layer is a coating film of a coating composition for a decorative layer, and is a layer that imparts decorative properties to the laminate. As the decorative layer, a base layer of a conventionally known topcoat coating film for automobiles, etc. can be used.

[0074] As the coating composition for the decorative layer, for example, the coating composition for the decorative layer described in Japanese Patent No. 7052119 can be used. Also, a coating composition for automobile repair can be used.

[0075] The coating composition for the decorative layer may be either water-based or solvent-based.

[0076] The thickness of the design layer may be adjusted as appropriate, and is, for example, 10 to 100 μm.

[0077] One embodiment of the laminate according to the present invention comprises a peelable adhesive layer, a design layer, and a clear layer, which are adjacent to each other in this order.

[0078] Other layers The laminate may have other layers in addition to the peelable adhesive layer and the clear layer or the design layer.

[0079] In one embodiment of the laminate according to the present invention, the peel strength is 3N or more. N is.

[0080] In one embodiment of the laminate according to the present invention, the peel strength after 80° C. / 100 hours is 10 N or less. In another embodiment, the peel strength of the laminate after 80° C. / 100 hours is 3 to 10 N.

[0081] In one embodiment of the laminate according to the present invention, the peel strength after an Xe test of 750 MJ is 10 N or less. In another embodiment, the peel strength of the laminate after an Xe test of 750 MJ is 3 to 10 N.

[0082] Laminate manufacturing method The laminate is produced, for example, by a method comprising step (I) of applying a coating material for an adhesive layer to an object to be coated to form a peelable adhesive layer, and step (II) of applying a coating composition for a design layer or a coating composition for a clear layer onto the peelable adhesive layer to form a design layer or a clear layer.

[0083] In addition, in the case of the laminate of Figure 4, for example, it is manufactured by a method comprising step (I) of applying a paint for an adhesive layer to an object to be coated to form a peelable adhesive layer, step (II) of applying a paint composition for a design layer onto the peelable adhesive layer to form a design layer, and step (III) of applying a paint composition for a clear layer onto the design layer to form a clear layer.

[0084] (subject to be coated) The substrate may be flat or three-dimensional. The material of the substrate is not particularly limited. For example, resin or steel plate can be used as the substrate material.

[0085] Examples of resins include polyethylene resin, EVA resin, polyolefin resin (polyethylene resin, polypropylene resin, etc.), vinyl chloride resin, styrene resin, polyester resin (including PET resin, PBT resin, etc.), polycarbonate resin, acrylic resin, acrylonitrile butadiene styrene (ABS) resin, acrylonitrile styrene (AS) resin, polyamide resin, acetal resin, phenolic resin, fluororesin, melamine resin, urethane resin, epoxy resin, polyphenylene oxide (PPO), etc.

[0086] Examples of steel sheets include metals such as iron, steel, stainless steel, aluminum, copper, zinc, and tin, as well as alloys thereof. The steel sheets may be subjected to a chemical conversion treatment, and an electrodeposition coating film may be formed thereon, as necessary. Examples of chemical conversion treatments include zinc phosphate conversion treatment, zirconium conversion treatment, and chromium oxide conversion treatment. The electrodeposition coating film may be formed by electrodeposition coating using a cationic electrodeposition coating composition or an anionic electrodeposition coating composition.

[0087] Examples of the substrate include the bodies of automobiles, trucks, motorcycles, buses, etc.; and automobile bodies having exterior clear coatings.

[0088] Examples of clear coating films for automobile exteriors include one-component curing coating films containing a polymerizable unsaturated monomer having an acid anhydride group, and two-component curing coating films containing a urethane resin.

[0089] Process (I) In step (I), a coating material for a peelable adhesive layer is applied to the substrate to form a peelable adhesive layer. The preparation of the coating material for a peelable adhesive layer, application, and formation of the peelable adhesive layer are as described above.

[0090] Process (II) In step (II), a coating composition for a design layer or a coating composition for a clear layer is applied onto the peelable adhesive layer to form a design layer or a clear layer. The application of the coating composition for a design layer may be carried out multiple times.

[0091] (Method for preparing coating composition (Y) for decorative layer) The coating composition for the decorative layer can be a known base coating for automobile exteriors or a base coating for automobile repair, and may be either water-based or solvent-based. The coating composition for the decorative layer may be a curing type or a lacquer type. The coating composition for the decorative layer may further contain a pigment. Examples of pigments include color pigments and luster pigments.

[0092] The coating method for the coating composition for the design layer is not particularly limited, and may be the same as that for the coating for the adhesive layer. The amount of coating composition for the design layer is not particularly limited, and is, for example, an amount such that the dry film thickness of the design layer is 10 to 20 μm. The coating composition for the design layer may be applied multiple times. After applying the coating composition for the design layer, the coating film is cured. The curing conditions may be appropriately set depending on the amount applied and the composition, and are, for example, about 20 minutes at 60°C.

[0093] The coating composition for the clear layer may be a known clear coating for automobile exteriors or a clear coating for automobile repair, and may be either water-based or solvent-based. The coating composition for the clear layer may also contain inorganic particles such as silica.

[0094] The coating method for the clear layer coating composition is not particularly limited, and may be the same as that for the peelable adhesive layer coating. The clear layer coating composition may be applied multiple times. The amount of the clear layer coating composition to be applied is not particularly limited, and may be appropriately determined depending on the performance required for the coating film, for example, such that the thickness of the clear coating film after curing is 40 to 60 μm. After the clear layer coating composition is applied, the coating film is cured under suitable curing conditions, such as at 70°C for 20 minutes.

[0095] ·Applications of laminates The use of the laminate is not limited and may be appropriately selected, for example, as a laminate for automobile exteriors for the purpose of changing the color of or protecting the exterior of an automobile. [Example]

[0096] The present invention will be described in more detail below with reference to examples, but these examples are intended to illustrate the present invention and are not intended to limit the present invention in any way. In the examples, "parts" means parts by mass.

[0099] (Preparation of object 1) An electrodeposition coating composition (Powernics 150, Nippon Paint Automotive Coatings Co., Ltd., Cationic) was electrodeposited onto a zinc phosphate-treated dull steel plate to a dry film thickness of 20 μm, followed by heat curing at 160°C for 30 minutes and cooling to prepare a steel plate substrate. An aqueous primer coating composition (AR-630-X 8110, Nippon Paint Automotive Coatings Co., Ltd.) was applied to the resulting substrate with an air spray gun to a dry film thickness of 25 μm and preheated in an oven set at 80°C for 3 minutes. Next, an aqueous base coating composition (AR-3020-1 202, Nippon Paint Automotive Coatings Co., Ltd.) was applied to the substrate with the primer layer with an air spray gun to a dry film thickness of 15 μm and preheated in an oven set at 80°C for 3 minutes. Furthermore, a clear coating composition (MAC O-1860 Clear, manufactured by Nippon Paint Automotive Coatings) was applied to the substrate having the intermediate coating layer and the base layer so that the dry film thickness was 35 μm. The coating was then heated in an oven set to 140°C for 30 minutes to obtain a coated substrate 1 having a multi-layer coating film.

[0101] ( For object 2 Clear for layers Preparation of the coating composition A mixture of 100 parts of Polyurexcel O-2100 Clear (manufactured by Nippon Paint Automotive Coatings) and 9.7 parts of TMK Thinner (a diluent, manufactured by Nippon Paint Automotive Coatings) was prepared as the base material. 38.3 parts of H-2100 (a hardener, manufactured by Nippon Paint Automotive Coatings) was prepared as the hardener. This curing agent was mixture and paint The mixture was mixed immediately before application to prepare a coating composition for the clear layer.

[0102] (Preparation of object 2) Steel plates with electrodeposition coatings were prepared in the same manner as for Substrate 1. Next, a solvent-based intermediate coating composition (OP-30-P DG 8110, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied using an air spray gun to a dry film thickness of 35 μm, and the resulting coating was heated in an oven set at 140°C for 30 minutes. Next, an aqueous base coating composition (AR-3020-1 202, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied using an air spray gun to a dry film thickness of 15 μm to the substrate with the intermediate coating layer, and the resulting coating was preheated in an oven set at 80°C for 3 minutes. Furthermore, the substrate with the intermediate coating layer and base layer was Prepared Clear for layers paint composition Things The coating was applied so that the dry film thickness would be 30 μm. Then, the coating was heated in an oven set at 140° C. for 30 minutes to obtain a coated object 2 having a multi-layer coating film.

[0104] ( For object 3 Clear for layers Preparation of the coating composition A mixture of 100 parts of R-2550-2 (manufactured by Nippon Paint Co., Ltd.) and 30 parts of T-5025 (a diluent, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was prepared as the base resin. 43.4 parts of H-2550 (a curing agent, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was prepared as the curing agent. This curing agent was mixture and paint Mix immediately before application and use as clear layer paint. composition was prepared.

[0105] (Preparation of object 3) An aqueous primer coating composition (WB-1200CD-5, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied to a polypropylene substrate using an air spray gun to a dry film thickness of 8 μm, and the substrate was preheated in an oven set to 80°C for 3 minutes. Next, an aqueous base coating composition (AR-3020-1 202, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied to a substrate having a primer layer using an air spray gun to a dry film thickness of 15 μm, and the substrate was preheated in an oven set to 80°C for 3 minutes. Furthermore, a substrate having a primer layer and a base layer was coated with Prepared Clear for layers paint composition Things The coating was applied so that the dry film thickness would be 30 μm. Then, the coating was heated in an oven set at 120° C. for 35 minutes to obtain a coated object 3 having a multi-layer coating film.

[0107] ( For object 4 Clear for layers Preparation of the coating composition A mixture of 100 parts of R-2550-1 (base agent, manufactured by Nippon Paint Automotive Coatings) and 30 parts of T-505HCL (thinner, manufactured by Nippon Paint Automotive Coatings) was prepared. 44 parts of H-2500 (hardener, manufactured by Nippon Paint Automotive Coatings) was prepared as a hardener. This curing agent was mixture and paint Mix immediately before application and use as clear layer paint. composition was prepared.

[0108] An aqueous primer coating composition (WB-1200CD-5, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied to a polypropylene substrate using an air spray gun to a dry film thickness of 8 μm, and the substrate was preheated in an oven set to 80°C for 3 minutes. Next, an aqueous base coating composition (AR-3020-1 202, manufactured by Nippon Paint Automotive Coatings Co., Ltd.) was applied to a substrate having a primer layer using an air spray gun to a dry film thickness of 15 μm, and the substrate was preheated in an oven set to 80°C for 3 minutes. Furthermore, a substrate having a primer layer and a base layer was coated with Prepared Clear for layers paint composition Things The coating was applied so that the dry film thickness would be 30 μm. Then, the coating was heated in an oven set at 120° C. for 35 minutes to obtain a coated object 4 having a multi-layer coating film.

[0109] Examples 1 to 4 A peelable adhesive layer coating, design layer coating composition 1, and clear layer coating composition 1 were prepared as follows, and laminates were produced.

[0110] Preparation of peelable adhesive coatings The following materials were charged in this order into a container equipped with a stirrer to obtain a first agent of a coating material for an adhesive layer. Urethane resin 67 parts (solids) Acrylic resin 33 parts (solids) Nopal 3303 (urethane associative thickener, manufactured by San Nopco) 2.0 parts BYK-345 (surface conditioner, manufactured by BYK) 0.6 parts Ion-exchanged water 57.8 parts

[0111] The second part used was nax E-CUBE WB water-based hardener (manufactured by Nippon Paint Co., Ltd.) The obtained first and second parts were mixed immediately before painting to prepare a paint for the adhesive layer.

[0112] Coating composition for decorative layer A lacquer-type coating composition 1 for the design layer was prepared by mixing 100 parts of nax E-CUBE WB 412 Silent Black (main agent, manufactured by Nippon Paint Co., Ltd.), 50 parts of nax E-CUBE WB 911 S-binder (auxiliary agent, manufactured by Nippon Paint Co., Ltd.), and 45 parts of nax E-CUBE WB R20 Standard Diluent (diluent, manufactured by Nippon Paint Co., Ltd.).

[0113] Clear layer coating composition A mixture of 100 parts of nax E-CUBE WB (2:1) NN Clear (manufactured by Nippon Paint Co., Ltd.) and 30 parts of pure water was prepared as the base material. 50 parts of nax E-CUBE WB water-based hardener (hardener, manufactured by Nippon Paint Co., Ltd.) was prepared as the hardener. This curing agent was mixture and paint The components were mixed immediately before coating to prepare clear layer coating composition 1.

[0114] (Preparation of laminate) Preparation of peelable adhesive layer The adhesive layer paint was applied with an air spray gun to the object to be coated 1. Subsequently, the object to be coated was heated in an oven set at 60°C for 20 minutes to produce a peelable adhesive layer.

[0115] Creating the design layer The decorative layer coating composition 1 was applied to a substrate having a peelable adhesive layer using an air spray gun, and the substrate was air-dried until the coating no longer adhered to the surface when touched with a finger. This coating and drying process was repeated two more times to form a decorative layer.

[0116] Preparation of clear layer A substrate having a peelable adhesive layer and a design layer was coated with clear layer coating composition 1 using an air spray gun. After leaving the substrate to stand for 30 minutes, the substrate was then heated in an oven set to 70°C for 20 minutes to form a clear layer.

[0117] (Examples 5 to 7) A laminate was produced in the same manner as in Example 1, except that the substrate was changed as shown in Table 1.

[0118] (Examples 8 and 9, Comparative Examples 1 to 3) A laminate was produced in the same manner as in Example 1, except that the coating composition for the adhesive layer and the film thickness of the peelable adhesive layer were changed as shown in Table 2.

[0119] Example 10 A laminate was produced in the same manner as in Example 1, except that the coating composition for the adhesive layer, the film thickness of the peelable adhesive layer, and the substrate were changed as shown in Table 2.

[0120] (Examples 11 to 13) A laminate was produced in the same manner as in Example 1, except that the coating composition for the adhesive layer and the film thickness of the peelable adhesive layer were changed as shown in Table 3.

[0121] (Examples 14 to 18, Comparative Example 4) A laminate was produced in the same manner as in Example 1, except that the coating composition for the adhesive layer and the film thickness of the peelable adhesive layer were changed as shown in Table 4.

[0122] (Examples 19 to 22, Comparative Examples 5 and 6) A laminate was produced in the same manner as in Example 1, except that the coating composition for the adhesive layer and the film thickness of the peelable adhesive layer were changed as shown in Table 5.

[0123] Example 23 A laminate was produced in the same manner as in Example 1, except that the paint for the peelable adhesive layer was dried at room temperature until it was dry to the touch, and the film thickness of the peelable adhesive layer was changed.

[0124] Example 24 A laminate was prepared in the same manner as in Example 1, except that the coating composition for the design layer and the coating composition for the clear layer were changed to the following coating composition for the design layer 2 and coating composition for the clear layer 2, and the film thickness of the peelable adhesive layer was changed. Preparation of coating composition 2 for design layer 100 parts of nax Real 611 Chinching Black NP (main agent, manufactured by Nippon Paint Co., Ltd.) and 33 parts of nax StabiR NEO #20 (diluting agent, manufactured by Nippon Paint Co., Ltd.) were mixed to prepare coating composition 2 for design layer. Preparation of clear layer coating composition 2 A mixture of 100 parts of nax Multi Eco (3:1) 20LX Clear (main agent, manufactured by Nippon Paint Co., Ltd.), 20 parts of nax Multi #20 Standard Urethane Thinner NEO (thinner, manufactured by Nippon Paint Co., Ltd.), and 33 parts of nax Ultra #20 Hardener (hardener, manufactured by Nippon Paint Co., Ltd.) was mixed immediately before painting to prepare clear layer coating composition 2.

[0125] Example 25 A laminate was prepared in the same manner as in Example 1, except that the coating composition for the design layer was not used, the coating composition for the clear layer was changed to the following coating composition for the clear layer 3, and the film thickness of the peelable adhesive layer was changed. Preparation of clear layer coating composition 3 A mixture of 100 parts of nax Multi Eco (3:1) Matte Clear (main agent, manufactured by Nippon Paint Co., Ltd.), 50 parts of nax Multi #20 Standard Urethane Thinner NEO (thinner, manufactured by Nippon Paint Co., Ltd.), and 33 parts of nax Ultra #20 Hardener (hardener, manufactured by Nippon Paint Co., Ltd.) was mixed immediately before painting to prepare clear layer coating composition 3.

[0126] (Comparative Examples 7 to 18) A laminate was produced in the same manner as in Example 1, except that the coating material for the adhesive layer was prepared as follows. Preparation of comparative adhesive layer paint The following materials were charged in this order into a container equipped with a stirrer to prepare a comparative adhesive layer coating material. Base resin dispersion (Table 7) 100 parts BYK-345 (surface conditioner, manufactured by BYK) 0.2 parts

[0127] (peel strength measurement) Using a tensile testing machine (Shimadzu Autograph AGX-V) equipped with a thermostatic chamber at 20°C, peel strength measurements were carried out between the peelable adhesive layer and the coated substrate under the following conditions: peel angle 180°, peel speed 300mm / min, and sample width 10mm. Peel strength measurements were carried out on three samples, and the average value was calculated and the adhesion was evaluated according to the following criteria. Adhesion pass: Peel strength is 3N / cm to 10N / cm Adhesion failure: Peel strength is less than 3N / cm or greater than 10N / cm

[0128] (heat resistance test) The prepared laminate was heated for 100 hours in an oven at 80° C. After being taken out, it was left to stand at room temperature for half a day or more, and then the peel strength was measured.

[0129] (Xe test) According to the xenon lamp method of JIS K5600-7-7, the laminate was attached to a Super Xenon Weather Meter SX-75 (manufactured by Suga Test Instruments Co., Ltd.), and the illuminance was 100 W / m 2 Accelerated exposure was carried out for 2100 hours at 4000 K.

[0130] [Table 1]

[0131] [Table 2]

[0132] [Table 3]

[0133] [Table 4]

[0134] [Table 5]

[0135] [Table 6]

[0136] [Table 7]

[0137] According to the present invention, it has been possible to provide a peelable adhesive layer that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. Also, according to the present invention, it has been possible to provide a laminate that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. [Industrial Applicability]

[0138] According to the present invention, it is possible to provide a peelable adhesive layer that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. Also, according to the present invention, it is possible to provide a laminate that has good adhesion so that it does not peel off during normal use and good releasability so that it can be peeled off at a desired time. [Explanation of symbols]

[0139] 1: Peelable adhesive layer 2: Clear layer 3: Design layer 10: Laminate

Claims

1. A peelable adhesive layer that is to be provided in contact with the exterior of an automobile and to be peeled off from the exterior, the peelable adhesive layer is a coating film of a paint for an adhesive layer, the adhesive layer coating material is a two-component type consisting of a first agent containing a water-dispersible acrylic resin and a water-dispersible urethane resin, and a second agent containing an isocyanate; The water-dispersible urethane resin has a glass transition temperature (Tg) of −80 to 0° C., the hydroxyl value of the water-dispersible acrylic resin is 40 to 165 mg KOH / g; A peelable adhesive layer to be provided in contact with the exterior of an automobile and to be peeled off from the exterior, wherein the ratio (NCO / OH) of the number of moles of isocyanate groups in the isocyanate to the number of moles of hydroxyl groups contained in the first agent is 0.5 to 2.

0.

2. A peelable adhesive layer as described in claim 1, wherein the ratio of the mass of the water-dispersed acrylic resin to the total mass of the water-dispersed acrylic resin and the water-dispersed urethane resin is 10 to 90 mass%.

3. Adjacent in order, The peelable adhesive layer according to claim 1 or 2, A laminate including a clear layer or a design layer, the peelable adhesive layer being provided in contact with the exterior of an automobile and being peeled off from the exterior.

4. The exterior has a clear coating film, 4. The laminate according to claim 3, wherein the clear coating film is a one-component coating film containing a polymerizable unsaturated monomer having an acid anhydride group, or a two-component coating film containing a urethane resin.

5. The laminate according to claim 4, which has a peel strength of 3N or more.

6. The laminate according to claim 4, wherein the peel strength after 80°C / 100 hours is 10 N or less.

7. The laminate according to claim 4, wherein the peel strength after an Xe test of 750 MJ is 10 N or less.

8. Adjacent in order, The peelable adhesive layer according to claim 1 or 2, A design layer and and a clear layer, the peelable adhesive layer being provided in contact with the exterior of an automobile and being peeled off from the exterior.

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