JP6874921B1 - Adhesive sheet, article and manufacturing method of article - Google Patents

Abstract

The problem to be solved by the present invention is that in the insert part molding process, it is possible to prevent the occurrence of distortion due to local heating when the molten resin is injected from the gate, and the molded product is left in a moist heat environment. However, it is an object of the present invention to provide an adhesive sheet capable of preventing the formation of air bubbles.
The present invention is an adhesive sheet used for insert molding for coating the surface of a decorative layer by injecting and applying a molten resin to the surface of the decorative layer after being attached to the surface of the decorative layer of the insert part. An adhesive sheet having an adhesive layer on which a pressure-sensitive or heat-sensitive adhesive is laminated on at least one surface of a base material, wherein the adhesive layer is specified in an atmosphere of a frequency of 3 Hz and a temperature of 85 ° C. and 200 ° C., respectively. It relates to an adhesive sheet having a tensile storage elasticity of 3 and having a loss tangent (tan δ) at a frequency of 3 Hz in a predetermined range under a predetermined temperature.

Description

The present invention relates to an adhesive sheet and an article to which the adhesive sheet is attached and a method for manufacturing the article.

Molded products with design characteristics such as ornaments and logo marks used in home appliances and automobiles are made of polycarbonate or polymethyl to protect the surface of the molded product from scratches when viewed from the design side. A translucent resin such as methacrylate is present on the surface layer, a decorative layer such as a printing layer or a metal vapor deposition layer is laminated on the back surface thereof, and a layer coated with a coating resin is laminated on the back surface thereof. There is.

As a method of coating the coating resin on the surface of the decorative layer, an insert part in which the translucent resin and the decorative layer are laminated is prepared in advance, set in a mold, and then the coating resin is heated to a melting temperature. A method of melting and coating by injecting a molten resin from an injection port called a gate onto the surface of the decorative layer by so-called insert molding is adopted.

When the coating resin is injected from the gate to the surface of the decorative layer at a high temperature, the translucent resin on the surface of the decorative layer near the gate and inside the decorative layer is exposed to the pressure and high temperature at the time of resin injection. Since it is exposed, it is easily damaged and distorted or the decorative layer is displaced, and there is a problem that it is visible as a mark of the gate opening from the design surface side of the molded product.

As a solution to the above problems, a method of suppressing damage to the decorative layer near the gate by providing a clear layer by printing on the surface of the decorative layer is exemplified (for example, Patent Document 1), but the clear layer is used. Since the thickness is about several μm, it is often the case that a sufficient suppressing effect is not obtained. Further, it is uneconomical to provide a thick clear layer in order to improve damage suppression because it is necessary to print the clear layer many times.

Further, as a solution to the above-mentioned problems, a method of attaching a protective film of the same material as the injection resin to the surface of the decorative layer to suppress damage to the decorative layer in the vicinity of the gate is exemplified (for example, Patent Document 2). ). However, since the protective film does not have an adhesive layer, there are problems such as the protective film falling off or being displaced when the insert parts are mounted on the insert molding machine. Further, when the completed molded product is left in a moist heat environment such as 85 ° C. and 85% RH, the gas generated from at least one of the translucent resin, the protective film, and the coating resin causes the protective film and the decorative layer to be separated from each other. In some cases, swelling occurred between them, and the design of the molded product was impaired. In particular, when the finished product is used for an automobile exterior part, the bulge may scatter and attenuate radar radio waves such as millimeter waves.

Japanese Unexamined Patent Publication No. 2004-181666 Japanese Unexamined Patent Publication No. 2014-181667

The problem to be solved by the present invention is to melt the coating resin on the surface of the decorative layer in the step of injecting the coating resin into the insert part in which the translucent resin and the decorative layer are laminated and performing insert molding. It is possible to prevent damage such as distortion and displacement due to deformation of the translucent resin and the decorative layer generated by local heating when ejecting from the gate, and damage to the adhesive sheet due to local heating. It is an object of the present invention to provide an adhesive sheet that can be easily adhered and fixed with high positional accuracy by preventing misalignment to a place where the decorative layer is desired to be protected, and is hard to fall off. Further, even after being heated by the injection of the coating resin, it is possible to prevent the formation of bubbles due to the gas that may be generated from the translucent resin, the coating resin, or the base material of the adhesive sheet, and the completed molded product is placed in a moist heat environment. It is an object of the present invention to provide an adhesive sheet capable of preventing the formation of air bubbles due to a translucent resin, a coating resin, or a gas that may be generated from the base material of the adhesive sheet even when left underneath, and preventing poor appearance.

The present inventor has found that the above problems can be solved by using the following adhesive sheet.
That is, it is an adhesive sheet used for insert molding that coats the surface of the decorative layer by injecting and applying a molten resin to the surface of the decorative layer after being attached to the surface of the decorative layer of the insert part. An adhesive sheet having an adhesive layer on which a pressure-sensitive adhesive or a heat-sensitive adhesive is laminated on at least one surface, wherein the adhesive layer has tensile storage elasticity measured at a frequency of 3 Hz in an atmosphere of 85 ° C. rate (E _'85) is in the range of ^{1 × 10 5 ~1 × 10 8} Pa, and the tensile storage elastic modulus was measured at a frequency 3Hz under an atmosphere of temperature ₂₀₀ ℃ (E' 200) is 1 × 10 ^An adhesive layer in the range of 5 to 1 × 10 ⁷ Pa and having a loss tangent (tan δ) measured at a frequency of 3 Hz of 0.8 or less in the temperature range of 60 ° C to 200 ° C. It provides an adhesive sheet having a layer.

The adhesive sheet of the present invention is used for the decorative layer in the step of injecting the coating resin and performing insert molding by locally attaching it to the decorative layer of the insert part in which the translucent resin and the decorative layer are laminated. When the coating resin is melted on the surface and injected from the gate, the adhesive sheet does not slip or peel off, preventing damage such as distortion and slippage due to local deformation of the translucent resin and the decorative layer due to heating. However, the design can be maintained for a long period of time by preventing the gas that may be generated from the translucent resin, the coating resin, or the base material of the adhesive sheet even after the finished molded product is left in a moist heat environment. Therefore, it can greatly contribute to the production of molded articles having a design property used for the exterior of home appliances, the interior and exterior of automobiles, and the like.

: It is a schematic cross-sectional view which shows one Embodiment of the adhesive sheet of this invention. : It is a schematic cross-sectional view which shows one Embodiment of the insert part to which the adhesive sheet of this invention is attached. : This is a schematic cross-sectional view showing an embodiment of an insert molding process in which an adhesive sheet of the present invention is attached to the surface of a decorative layer of an insert part, a coating resin is melted and injected from a gate to coat the insert part. : A schematic cross-sectional view showing an embodiment of an article in which an insert part including a translucent resin and a decorative layer, an adhesive sheet of the present invention, and a coating resin are laminated in this order.

The adhesive sheet of the present invention is an adhesive sheet in which a pressure-sensitive adhesive or a heat-sensitive adhesive is laminated on at least one surface of a base material. An example of a cross-sectional view of a preferred embodiment is given in FIG.
_{Further, the tensile storage elastic modulus (E'85} ) measured at a frequency of 3 Hz in an atmosphere of a temperature of 85 ° C. is in the range of 1 × 10 ⁵ to 1 × 10 ⁸ Pa, and the frequency is in an atmosphere of a temperature of 200 ° C. an adhesive layer measured tensile storage modulus (E _'200) is in the range of ^{1 × 10 5 ~1 × 10 7} Pa at 3 Hz, and the loss tangent measured at the frequency 3 Hz (tan [delta) is, It is an adhesive sheet having an adhesive layer having a temperature of 0.8 or less in the range of 60 ° C. to 200 ° C. Here, the loss tangent (tan δ) refers to a numerical value obtained by dividing the measured value of the tensile loss elastic modulus by the measured value of the tensile storage elastic modulus.

Here, the insert part refers to a part manufactured in advance to be attached to the insert molding machine before the coating resin is discharged from the gate by the insert molding machine and laminated.

By attaching the adhesive sheet to the surface of the decorative layer of the insert part, the coating resin is melted and injected from the gate to cover the surface of the decorative layer of the insert part in which the translucent resin and the decorative layer are laminated. In the insert molding process, in order to prevent damage such as distortion and displacement due to deformation of the decorative layer due to local heating of the coating resin, the adhesive sheet does not shift or peel off, and it is easy and highly accurate. It can protect from damage and prevent the formation of bubbles due to the gas that can be generated from the translucent resin, the coating resin, or the base material of the adhesive sheet even if the finished molded product is left in a moist heat environment. be able to.

[Base material]
As the base material of the adhesive sheet, the same base material as the coating resin coated on the surface of the decorative layer of the insert part is used. The same base material here means that the resin used for the base material is the same type as the coating resin, and for example, the types of additives such as colorants and plasticizers may be different. Further, the resin used for the base material and the coating resin are preferably resins having the same monomers and polymerized or copolymerized at the same ratio, but if the resin composition is compatible with the coating resin, the resin of the base material can be used. It may be used. For example, when the coating resin uses an acrylonitrile / styrene copolymer, a compatible polystyrene may be used as the base material.

By using the same base material as the coating resin, when the coating resin is melted and injected from the gate, the surface of the base material of the adhesive sheet softens and becomes compatible with the coating resin, so that the base material and the coating resin become By improving the adhesion, it is possible to prevent floating and peeling due to the gas generated when the resin is left in a moist heat environment for a long period of time. In particular, when used for automobile exterior parts, it is possible to prevent radar radio waves such as millimeter waves from being scattered and attenuated by voids.

Types of resin for the base material include polycarbonate, polymethylmethacrylate, polystyrene, polypropylene, acrylonitrile / butadiene / styrene copolymer, acrylonitrile / styrene copolymer, and acrylonitrile / styrene, which are used as coating resins for molded products. Acrylic acid ester copolymer, acrylonitrile / ethylene / propylene / diene / styrene copolymer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer Examples thereof include coalescence, polymethylpentene, polyether ether ketone, polyether sulfone, polyetherimide, polyimide, fluororesin, nylon and the like. Among them, styrene-based polymers or styrene-based copolymers are often used as coating resins because they can be melted at a temperature of about 200 ° C. and have excellent fluidity at the time of melting. In this case, they are the same. It is preferable to use the styrene resin of the above as a base material. In particular, an acrylonitrile / butadiene / styrene copolymer or an acrylonitrile / ethylene / propylene / diene / styrene copolymer having excellent flexibility and impact resistance is preferably used as a coating resin, and the same acrylonitrile / butadiene / base material is also used as a base material. Most preferably, a styrene copolymer or an acrylonitrile / ethylene / propylene / diene / styrene copolymer is used.

The color of the base material is preferably the same color as the transparent or coating resin without being decorated by itself so that the pasted pattern of the adhesive sheet can be seen from the translucent resin side and does not impair the design. .. If the base material is transparent, the color of the coating resin is transmitted and the adhesive sheet is not visible. On the other hand, if the base material is colored in the same color as the coating resin, no color difference occurs at the boundary surface between the adhesive sheet and the coating resin, and the adhesive sheet cannot be visually recognized.

When the transparent base material is used, the base material is preferably colorless and transparent, and the haze measured according to JIS K7136 is preferably 5% or less, and in order to transmit the color of the coating resin, 2 % Or less is more preferable.

When a base material colored in the same color as the coating resin is used, the color difference (ΔE) from the coating resin measured by the L * a * b color space coordinates of CIE1976 is preferably 5.0 or less, and the coating resin. ΔE is more preferably less than 3.0 in order not to cause a color difference with. As a method for coloring the base material, an organic pigment, an inorganic pigment, a master batch in which the pigment is kneaded, a dry color, or the like may be added so as to be within the above range.

The amount of the organic pigment, the inorganic pigment, the masterbatch in which the pigment is kneaded, the dry color, or the like is not particularly limited as long as the compatibility between the coating resin and the base material is not impaired, but the compatibility with the coating resin is not particularly limited. In order to maintain the mechanical properties of the or base material, 1 to 30% by mass is preferable, and 5 to 10% by mass is particularly preferable.

In addition to the resin and the coloring component, an antistatic agent, an antioxidant, a lubricant, an ultraviolet absorber or a light stabilizer, an inorganic filler for improving strength, or the like may be added to the base material.

The thickness of the base material may be sufficient to withstand the temperature at which the coating resin is injected, but it should be within the range of 50 to 2000 μm in order to prevent damage to the insert parts. It is preferably in the range of 150 to 1000 μm, and more preferably in the range of 200 to 400 μm in terms of preventing damage, cutting processability, and adhesive followability to the surface of the decorative layer of the insert part. Is particularly preferred. If the thickness of the base material is less than 50 μm, the heat at the time of injection of the coating resin is transferred to the surface of the insert part and easily causes local heat damage. If it exceeds 2000 μm, the adhesive sheet is cut into an arbitrary shape. In addition to this, it becomes difficult to bury it in the coating resin, and the adhesive sheet floats on the surface of the molded product on the coating resin side.

Examples of the method for producing the base material include a method in which a resin composition obtained by mixing the resin, a colorant, an additive and the like is melted at a high temperature and extruded from a die to form a film, an inflation film forming method, a calendar film forming method and the like. It can be obtained by any film forming method. If necessary, the surface of the base material may be processed into a glossy or matte shape by a pressure roll at the time of film formation, and in order to improve the adhesion with the adhesive, the surface is roughened by a sandblasting method or a solvent treatment method, or a corona. Surface treatment such as discharge treatment, chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment, corona treatment, plasma treatment and the like may be performed.

[adhesive]
As the adhesive, a pressure-sensitive adhesive or a heat-sensitive adhesive is used. The pressure-sensitive adhesive refers to an adhesive that adheres to the surface of an adherend only by applying a pressure of about finger pressure at room temperature. Further, the heat-sensitive adhesive refers to an adhesive that does not adhere at all under a pressure of about finger pressure at room temperature or is slightly adhesive, but adheres to an adherend with high strength by heating at about 60 ° C. or higher. An adhesive sheet shaped according to the size of the gate is attached according to the position closest to the gate on the surface of the decorative layer of the insert part, and the adhesive sheet can be reattached to correct the attachment position. It is preferable to use a heat-sensitive adhesive having a slight adhesiveness at room temperature. The term "slightly adhesive" as used herein means that the peeling adhesive force at the time of pressure-sensitive bonding, which will be described later, is 1 N / 25 mm or less.

_{As the adhesive, the tensile storage elastic modulus (E'85} ) measured at a frequency of 3 Hz in an atmosphere of a temperature of 85 ° C. is in the range of 1 × 10 ⁵ to 1 × 10 ⁸ Pa, and the temperature is 200 ° C. under the atmosphere, is the measured tensile storage modulus at a frequency 3Hz (E _'200) is in the range of ^{1 × 10 5 ~1 × 10 7} Pa, and the loss tangent measured at the frequency 3 Hz (tan [delta) is , 0.8 or less in the temperature range of 60 to 200 ° C.

When the _E'85 is in the above range, bubbles due to gas that can be generated from either a translucent resin, a coating resin, or a base material of an adhesive sheet when the finished molded product is left in a moist heat environment. When a heat-sensitive adhesive is used, it can be heat-sensitively adhered to the surface of the insert part with high strength by heating at 60 ° C. or higher. Wherein E _'85 is, in order to more firmly prevent the formation of air bubbles when it is left under wet heat environment, preferably in the range of ^{1.5 × 10 5 ~3 × 10 7} Pa Among the above-described range, The range of 2.5 × 10 ⁵ to 1 × 10 ⁷ Pa is more preferable. On the other hand, if the surface hardness to be described below is stuck high the adhesive sheet to the coated surface, to enhance the adhesion at the time of pressure-sensitively adhere, the E _'85 is also 1 × 10 ⁵ ~ in the aforementioned range and more preferably in a range of 1 × 10 ^7.

Further, when the resin used in the adhesive is a resin having no ester bond in the main chain, the E _'85, among the above-described range, in the range of from ^{1 × 10 5 ~1 × 10 7} Pa It is preferably in the range of ^{1.5 × 10 5 to} 5 × 10 ⁶ Pa, more preferably in the range of ^{2.5 × 10 5} to 2 × 10 ^{6 Pa.} The E _'85 when the resin used in the adhesive is a resin having no ester bond in the main chain in this range, from the blistering between the protective film and the decorative layer by bubble generation caused In addition to the effect of suppressing and the effect of enabling high-strength adhesion to the surface of the insert part, it is possible to suppress a significant decrease in adhesiveness when exposed to a moist heat environment for a period of about 250 hours or more. Is.

If the E _'200 is in the above range, when the coating resin melted at a high temperature to the adhesive sheet surface is emitted from the gate, it is possible to prevent displacement of the adhesive sheet and peeling, and the heat of the coating resin The adhesive layer is not crushed by pressure, the original thickness of the adhesive layer can be maintained, and the strain of the adhesive layer due to a sudden temperature change due to the molten resin can be absorbed to maintain the adhesion to the decorative layer. E _'200 is, in order to reliably prevent peeling displacement of the adhesive sheet and the heat and pressure of the coating resin is preferably in the range of ^{2 × 10 5 ~3 × 10 6} Pa, 3 × 10 5 ~1 × The range of 10 ⁶ Pa is more preferable.

When the tan δ is in the above range, it is possible to suppress the formation of air bubbles in a moist heat environment and prevent the adhesive layer from being deformed during insert molding. In particular, tan δ should be 0.4 or less in the temperature range of 60 to 200 ° C. to ensure the suppression of bubble formation in a moist heat environment and the prevention of deformation of the adhesive layer during insert molding. Is more preferable, and 0.3 or less is more preferable. Further, the tan δ may be larger than 0, preferably 0.01 or more, preferably 0.02 or more, and 0.1 or more to prevent deformation of the adhesive layer during insert molding. It is more preferable to ensure the above.

When the resin used for the adhesive is a resin having no ester bond in the main chain, the tan δ is preferably in the range of 0.01 to 0.4 among the above-mentioned ranges. It is more preferably in the range of 0.01 to 0.3, and more preferably in the range of 0.02 to 0.3. When the resin used for the adhesive is a resin that does not have an ester bond in the main chain, by setting the tan δ in this range, it is possible to prevent the occurrence of swelling between the protective film and the decorative layer due to the generation of air bubbles, and insert molding. In addition to being able to prevent deformation of the adhesive layer at the time, when the adhesive sheet of the present invention is attached to an insert part provided with a thin film metal layer as a decorative layer, a period of about 250 hours or more in a moist heat environment. This is because it is possible to suppress a significant decrease in adhesiveness even when exposed.

Further, in an atmosphere of temperature of 25 ° C., measured tensile storage modulus at a frequency 3Hz (E _'25) is preferably in the range of ^{1 × 10 5 ~1 × 10 8} Pa. If the E _'25 is in the above range, pressure sensitive or can slightly adhesive at about finger pressure, the adhesive sheet can be stuck in a simple manner and with high positional accuracy according to the position of the gate, the insert from the heating of the resin coating It is possible to effectively protect the damage on the surface of the parts. More preferably slightly adhesive in order to impart the reattachment of the E _'25 is more preferably in the range of ^{5 × 10 5 ~5 × 10 7} Pa, 1 × 10 6 ~1 × 10 7 The range of Pa is more preferable.

Further, in order to impart pressure-sensitive adhesiveness and slight adhesiveness at room temperature, the peak temperature of the tan δ is preferably -20 to 20 ° C., in order to facilitate reattachment and positioning of the adhesive sheet. The peak temperature of tan δ is preferably within -10 to 10 ° C.

Incidentally, the tensile storage modulus _{(E '25, E' 85} , E '200) and the loss tangent (tan [delta) is a dynamic viscoelasticity tester (TA Instruments Ltd. viscoelasticity measuring instrument "RSA Using "III", in tensile mode, under the conditions of frequency 3 Hz, heating rate 5 ° C / min, load strain 0.1-0.6%, tensile storage elastic modulus in the temperature range from -20 to 210 ° C. E'and loss tangent tan δ are measured. As the test piece used in the above measurement, the adhesive is 400 μm and the width is 5 mm, the length of the measuring part is 20 mm, and the lengths of the handles at both ends are each. to use a was cut into 15mm rectangular. Incidentally, the tensile storage modulus E _{'25, E' 85,} and E _'200 the whole, tensile storage modulus E at a given temperature' may be referred to as.

In order for the adhesive sheet not to affect the design of the molded product, the adhesive is preferably colorless and transparent, and the haze measured in accordance with JIS K7136 is preferably 5% or less, and the coating resin and the base. 2% or less is more preferable for transmitting the color of the material. Further, if necessary, an organic pigment, an inorganic pigment, or a dye may be added to the adhesive to adjust the hue so that the color difference (ΔE) between the coating resin and the base material is less than 3.0.

As the resin used for the adhesive, any adhesive having the above-mentioned range of physical characteristics can be used, and an adhesive resin such as an acrylic resin, an epoxy resin, a polyester resin, or a urethane resin can be used.

The storage modulus _{(E '25, E' 85} , E '200) and a loss tangent tanδ in designing the desired range tension, resin used in the adhesive, may include a polyester resin and urethane resin Above all, it is more preferable that the composition is composed of a composition containing a polyester resin and a polyester urethane resin and is crosslinked with an isocyanate compound. Among the urethane resins, the polyester urethane resin has good compatibility with the polyester resin, and the compound containing the polyester resin and the polyester urethane resin forms a crosslinked structure with the isocyanate compound, so that the pressure-sensitive adhesiveness and aggregation are achieved. This is because the property can be adjusted to a suitable range and the adhesive strength can be enhanced.

More specifically, the adhesive is preferably a composition in which a polyester resin and a polyester urethane resin are blended and the gel content is adjusted to 40 to 95% by mass by isocyanate cross-linking or the like, and bubbles are formed in a moist heat environment. The composition adjusted to 40 to 80% by mass is more preferable, and the composition adjusted to 50 to 70% by mass is most preferable, in order to more reliably suppress the reaction of the adhesive layer and prevent the adhesive layer from being deformed during insert molding. Here, when the adhesive sheet is attached to a coated surface having a high surface hardness such as baking type acrylic coating, urethane coating, melamine coating, etc., the glass transition of polyester urethane resin is performed in order to enhance the adhesive force at the time of pressure-sensitive adhesion. The temperature may be used in the range of -30 to 60 ° C. In this case, the composition in which the gel fraction is adjusted to 55 to 95% by mass in order to suppress the displacement and peeling of the adhesive sheet during insert molding and the formation of air bubbles in a moist heat-leaving environment. Is more preferable, and 70 to 90% by mass is most preferable.

In the present specification, the gel fraction is calculated by the following formula.
Gel fraction (mass%) = [(mass of adhesive layer after immersion in toluene) / (mass of adhesive layer before immersion in toluene)] × 100

The polyester resin is not particularly limited, and a polyester resin which is a condensate of a polyvalent carboxylic acid and a polyhydric alcohol or a modified polyester resin can be usually used.

The polyester resin may be a kind of polyester resin or a mixture of a plurality of polyester resins, but in order to impart pressure-sensitive adhesiveness at 25 ° C. and heat-sensitive adhesiveness having slight adhesiveness to the adhesive. It is preferable to contain a polyester resin having a glass transition temperature of 0 ° C. or lower, more preferably to contain a polyester resin having a glass transition temperature of 40 to 0 ° C. It is most preferable to contain a polyester resin at −30 to −10 ° C. in order to suppress the formation of air bubbles underneath and prevent the adhesive sheet from slipping or peeling during insert molding.

The number average molecular weight of the polyester resin is preferably 10,000 to 40,000, more preferably 20,000 to 30,000. By containing a polyester resin having a number average molecular weight in the above range, it has excellent compatibility with a polyester urethane resin, it is easy to maintain the transparency of the adhesive, and repelling occurs when it is applied on a release liner. It is difficult, and the shape of the adhesive layer is less likely to be lost during insert molding or heat-sensitive adhesion.

The polyester resin preferably has a hydroxyl value of 3 to 50 KOHmg / g in order to adjust the gel fraction to the preferred range and to set the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within the desired ranges. .. 5 to 10 KOHmg / g is more preferable in order to have heat-sensitive adhesiveness having pressure-sensitive adhesiveness or slight adhesiveness at room temperature and to prevent the adhesive sheet from slipping or peeling during insert molding.

When the surface of the decorative layer of the insert part is a thin metal layer, the acid value of the polyester resin is preferably 3 KOHmg / g or less in order to avoid oxidative damage to the decorative layer due to corrosion, and oxidative damage to the decorative layer is caused. In order to prevent it, less than 1 KOH mg / g is particularly preferable.

Examples of the polyvalent carboxylic acid used in the polyester resin include phthalic acid, isophthalic acid, terephthalic acid, maleic acid, itaconic acid, fumaric acid, tetrahydrophthalic acid, hexahydrophthalic acid, adipic acid, sebacic acid, azelaic acid, and tri. Examples thereof include merit acid, methylcyclohexentricarboxylic acid or pyromellitic acid, dimer acids derived from unsaturated fatty acids, and acid anhydrides thereof, and these carboxylic acids are usually used alone or in combination of two or more. Be done.

Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,4 butanediol, 1,3 butanediol, neopentyl glycol, pentamethylene glycol, hexamethylene glycol, and heptamethylene glycol. Octamethylene glycol and the like can be mentioned. Further, a polyhydric alcohol containing a carboxylic acid group may be used as the polyhydric alcohol, and particularly typical examples thereof include dimethylolpropionic acid, dimethylolbutanoic acid, and diphenolic acid. Further, by modifying the polyhydric alcohol with a caprolactone compound such as ε-caprolactone, the glass transition temperature of the polyester resin can be lowered, and the tensile storage elastic modulus E'and the loss tangent tan δ at the predetermined temperature can be set in the target range. Easy to control.

The condensation reaction between the polyvalent carboxylic acid and the polyhydric alcohol is obtained according to various known and commonly used synthetic methods. For example, the polyvalent carboxylic acid and the polyhydric alcohol are added together. A synthetic method of condensation (esterification) is common.

Further, in the condensation reaction between a polyvalent carboxylic acid and a polyhydric alcohol, if a trivalent or higher carboxylic acid or alcohol is used, a branched structure can be imparted to the obtained condensate.

The content of the polyester resin in the adhesive is preferably 40 to 90% by mass, more preferably 60 to 80% by mass. When the content is within the range, it is easy to control the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within the target range, and it is easy to maintain the transparency of the adhesive on the release liner. When applied, the adhesive layer is less likely to lose its shape during repelling, insert molding, and heat-sensitive adhesion.

As the polyester urethane resin, a polyester urethane resin obtained by reacting a hydroxyl group-containing polyester with a polyisocyanate compound can be preferably used.

As the polyester urethane resin, a kind of polyester urethane resin may be used, or a plurality of polyester urethane resins may be mixed, but a polyester urethane resin having a number average molecular weight of 15,000 to 100,000 shall be used. Is preferable.

Further, as the polyester urethane resin, a polyester urethane resin having a glass transition temperature of preferably 10 to 100 ° C., more preferably 40 to 85 ° C. is used, so that the tensile storage elastic modulus E'at a predetermined temperature and loss tangent are in contact with each other. It is easy to control tan δ to the target range. On the other hand, when the adhesive sheet is attached to a coated surface having a high surface hardness such as baking type acrylic coating, urethane coating, or melamine coating, the glass transition temperature of the polyester urethane resin is increased in order to enhance the adhesive force during pressure-sensitive adhesion. Is preferably -30 to 60 ° C, more preferably -20 to 30 ° C, and most preferably -10 to 20 ° C.

As the hydroxyl group-containing polyester resin used for the polyester urethane resin, a polyester resin obtained by condensing a polyvalent carboxylic acid and a polyhydric alcohol can be used as in the polyester resin. The hydroxyl group-containing polyester resin preferably has a number average molecular weight in the range of 4,000 to 20,000.

The polyester urethane resin preferably has a hydroxyl value of 3 to 50 KOHmg / g, has pressure-sensitive adhesiveness or slightly adhesiveness at room temperature, and has a heat-sensitive adhesiveness in order to keep the gel fraction in the preferable range. In order to prevent the adhesive sheet from slipping or peeling during molding, 5 to 10 KOH mg / g is more preferable.

When the surface of the decorative layer of the insert part is a thin metal layer, the acid value of the polyester urethane resin is preferably 3 KOHmg / g or less in order to avoid oxidative damage to the decorative layer due to corrosion, and oxidative damage to the decorative layer. It is particularly preferable that it is less than 1 KOH mg / g in order to prevent the above.

As the polyisocyanate compound to be reacted with the hydroxyl group-containing polyester resin, known aromatic, aliphatic, and alicyclic isocyanate compounds can be used. Examples of the aliphatic isocyanate compound include hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, and xylylene diisocyanate. Typical examples of the alicyclic isocyanate compound include isophorone diisocyanate, methylcyclohexane diisocyanate, lysine diisocyanate, and cyclohexane-1,4 diisocyanate. Examples of the aromatic isocyanate compound include toluene diisocyanate, 1,5-naphthylene diisocyanate, 4, 4'-diphenylmethane diisocyanate, 4, 4'-diphenyldimethylmethane diisocyanate, 4, 4'-dibenzyl diisocyanate, and tetraalkyldiphenylmethane diisocyanate. Typical examples include dialkyldiphenylmethane diisocyanate, 1,3'-phenylenediocyanate, and 1,4'-phenylenediocyanate.
In addition, compounds obtained from one or several of the above-mentioned isocyanates (dimers, trimers, nurates, adducts, burettes, prepolymers, etc.) can also be used.

The content of the polyester urethane resin is preferably 5 to 40% by mass, particularly preferably 15 to 35% by mass in the adhesive. By setting the content in the above range, it is easy to control the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within the target range, and an appropriate cohesive force can be imparted. In addition to preventing slippage and peeling, it is easy to prevent the formation of bubbles when the molded product is left moist and hot.

The resin used for the adhesive may or may not have an ester bond in the main chain as long as the adhesive can satisfy the above-mentioned physical characteristics, but the resin used in the main chain may have an ester bond. It is preferably a resin having no bond. In particular, when the adhesive sheet of the present invention is attached to an insert part provided with a thin metal layer as a decorative layer, the resin used for the adhesive may be a resin having no ester bond in the main chain. preferable. A resin having an ester bond in the main chain is hydrolyzed by being exposed to a moist heat environment for a long period of time (for example, for a period of about 250 hours or more) to generate a carboxylic acid, whereby the metal layer which is a decorative layer is oxidized. It is easy to fade (transparent). On the other hand, by forming an adhesive layer using a resin having no ester bond in the main chain, it is contained in the adhesive layer even if it is exposed to a moist heat environment for a long period of time (for example, a period of about 250 hours or more). This is because the resin is less likely to be hydrolyzed in the main chain, and the carboxylic acid generated from the adhesive layer can prevent the metal layer from being oxidized and fading (transparent). That is, the adhesive sheet of the present invention has an adhesive layer formed of a composition containing a resin having no ester bond in the main chain, thereby having an effect of suppressing the generation of air bubbles in a moist heat environment and to the surface of the insert part. In addition to the effect of being able to adhere to high strength, it is possible to suppress deterioration of the design of the insert parts in a moist heat environment.

Specific examples of the resin having no ester bond in the main chain include acrylic resin, polyether urethane resin, polycarbonate urethane resin, cured product of epoxy resin, and copolymerization of olefin monomer having diene and styrene monomer. Examples thereof include resins such as resins and hydrogenated resins of these resins. Of these, acrylic resins are preferable because they can be pressure-sensitively bonded at room temperature and the adhesive strength to insert parts can be further increased. A resin having no ester bond in the main chain is a metal layer as long as the carboxylic acid is bonded to the side chain of the main chain even if it is hydrolyzed by being exposed to a moist heat environment for a period of about 250 hours or more. May have an ester bond in the side chain because it is unlikely to cause oxidation.

As the acrylic resin, it is preferable to use a polymer of (meth) acrylic acid ester or a polymer of the (meth) acrylic acid ester and another vinyl monomer, and the alkyl (meth) acrylate monomer is the main monomer. As a component, an acrylic copolymer which is a polymer of the main monomer component and another vinyl monomer is preferable. The alkyl group contained in the alkyl (meth) acrylate monomer may be linear or branched.

The alkyl (meth) acrylate monomer is preferably an alkyl (meth) acrylate monomer having 1 to 12 carbon atoms. Examples of such an alkyl (meth) acrylate monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, and n-. Examples include monomers such as hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isobonyl (meth) acrylate. Be done. One kind or two or more kinds of these monomers can be used.

Of these, an alkyl (meth) acrylate having an alkyl group having 4 to 12 carbon atoms is preferable, and an alkyl (meth) acrylate having a linear or branched structure having an alkyl group having 4 to 8 carbon atoms is more preferable. In particular, n-butyl acrylate is preferable because it is easy to secure adhesion to the adherend.

Further, in the present invention, it is preferable to use n-butyl acrylate and methyl acrylate as the alkyl (meth) acrylate monomer. That is, the acrylic polymer preferably contains n-butyl acrylate and methyl acrylate in the monomer unit. This is because the glass transition temperature (Tg) of the acrylic copolymer can be adjusted to an appropriate temperature in order to enhance the pressure-sensitive adhesive force of the adhesive layer. The content of n-butyl acrylate and methyl acrylate in the total amount of the alkyl (meth) acrylate monomer is preferably in the range of 50% by mass to 99% by mass, and more preferably in the range of 70% by mass to 95% by mass.

The content of one or more selected from the group consisting of alkyl (meth) acrylate monomers with respect to the total amount of the acrylic monomers constituting the acrylic copolymer is preferably 70% by mass or more, preferably 75 to 99. It is more preferably in the range of mass%, and even more preferably in the range of 80 to 98% by mass.

In addition to the above-mentioned alkyl (meth) acrylate monomer, nitrogen-containing vinyl monomer such as acrylonitrile and N-vinyl-2-pyrrolidone, styrene, vinyl acetate, and hydroxyl group-containing vinyl monomer are used as the monomers constituting the acrylic copolymer. Etc. may be used alone or in combination of two or more. Among them, a hydroxyl group-containing vinyl monomer is preferable. That is, the acrylic copolymer is preferably a copolymer containing an alkyl (meth) acrylate monomer and a hydroxyl group-containing vinyl monomer in a monomer unit. It reacts with an isocyanate compound described later to form a crosslinked structure, and it is easy to adjust the pressure-sensitive adhesiveness and cohesiveness to a suitable range. In addition, the side chain ester is hydrolyzed by being exposed to a moist heat environment for about 250 hours or more. This is because even if it is decomposed, a remarkable decrease in adhesiveness can be suppressed.

Examples of the hydroxyl group-containing vinyl monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. ) Acrylate, 2-hydroxyhexyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylic, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate and other hydroxyl groups Included (meth) acrylates.

The content of the hydroxyl group-containing vinyl monomer with respect to the total amount of the acrylic monomers constituting the acrylic copolymer is preferably in the range of 0.1 to 20% by mass, preferably in the range of 0.5 to 10% by mass. It is preferably in the range of 1 to 5% by mass.

Further, when the adhesive sheet of the present invention is attached to an insert part provided with a thin metal layer as a decorative layer, the metal provided on the insert part is exposed to a moist heat environment for a period of about 250 hours or more. In order to prevent the layer from being oxidized and fading (transparent), it is preferable that the monomer constituting the acrylic copolymer does not contain a (meth) acrylic acid monomer containing a carboxyl group.

The molecular weight of the acrylic copolymer is preferably in the range of 100,000 to 1.5 million, more preferably in the range of 300,000 to 1,000,000, and is preferably in the range of 400,000 to 800,000. Within the range, it is easy to control the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within the target range, and distortion or displacement due to deformation of the decorative layer due to local heating of the coating resin, etc. It is more preferable to prevent the damage caused by the resin and to prevent the formation of bubbles even if the finished molded product is left in a moist heat environment.

In the present specification, the weight average molecular weight is the molecular weight in terms of standard polystyrene measured by gel permeation chromatography (GPC), and is under the following conditions using a GPC device (HLC-8329 GPC) manufactured by Tosoh Corporation. Use the standard polystyrene conversion value to be measured.
(conditions)
Sample concentration: 0.5% by mass (THF solution)
Sample injection volume: 100 μL
Eluent: THF
Flow velocity: 1.0 mL / min Measurement temperature: 40 ° C
Main column: TSKgel GMHXL 4 guard columns: TSKgel HXL-H
Detector: Differential refractometer Standard polystyrene Molecular weight: 10,000 to 20 million (manufactured by Tosoh Corporation)

The glass transition temperature of the acrylic resin is preferably 0 ° C. or lower, more preferably in the range of −50 ° C. to 0 ° C., and more preferably in the range of −35 ° C. to −10 ° C. While controlling the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within the target range, the adhesive sheet of the present invention can exhibit high pressure-sensitive adhesiveness, and can be used for baking-type acrylic coating or urethane coating. This is because it can be attached to a painted surface having a high surface hardness such as melamine coating with a high adhesive force at room temperature.

The adhesive layer in the adhesive sheet of the present invention is formed of a resin having no ester bond in the main chain and an adhesive containing a cross-linking agent, and the resin having no ester bond in the main chain is cross-linked. That is, it is preferably a crosslinked product of a composition containing a resin having no ester bond in the main chain and a crosslinking agent. Above all, the adhesive layer is more preferably crosslinked so that the gel fraction is in the range of 55 to 95% by mass, and is crosslinked so that the gel fraction is in the range of 70 to 90% by mass. It is more preferable that it is. This is because the adhesive force at the time of pressure-sensitive adhesion can be enhanced, the displacement and peeling of the adhesive sheet at the time of insert molding can be suppressed, and the formation of air bubbles in a moist heat-leaving environment can be suppressed. In particular, when the resin having no ester bond in the main chain is an acrylic resin, the adhesive layer may be crosslinked within the gel fraction described above so that good pressure-sensitive adhesiveness can be exhibited. preferable. The details of the cross-linking agent will be described later.

The adhesive used for the adhesive sheet preferably contains a cross-linking agent. As the cross-linking agent, an isocyanate compound can be preferably used. By cross-linking with an isocyanate compound, it is easy to control the tensile storage elastic modulus E'and the loss tangent tan δ at a predetermined temperature within a target range. As the isocyanate compound, known isocyanate compounds of aromatic, aliphatic and alicyclic groups can be used, but from the viewpoint of safety and yellowing resistance, aliphatic and / or alicyclic isocyanate compounds can be preferably used.

Examples of the aliphatic isocyanate compound include hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, and xylylene diisocyanate.

Examples of the alicyclic isocyanate compound include isophorone diisocyanate, methylcyclohexane diisocyanate, lysine diisocyanate, and cyclohexane-1,4 diisocyanate.

Examples of the aromatic isocyanate compound include tolylene diisocyanate, 1,5-naphthylene diisocyanate, 4, 4'-diphenylmethane diisocyanate, 4, 4'-diphenyldimethylmethane diisocyanate, 4, 4'-dibenzyl diisocyanate, and tetraalkyldiphenylmethane diisocyanate. Examples thereof include dialkyldiphenylmethane diisocyanate, 1,3'-phenylenediocyanate and 1,4'-phenylenediocyanate.

The isocyanate compound also includes a compound (dimer, trimer, adduct, burette, prepolymer, etc.) obtained from one or several of the above-mentioned isocyanates. Among these isocyanate compounds, aliphatic or alicyclic isocyanate compounds are suitable as those used in the present invention, and among these, hexamethylene diisocyanate and isophorone diisocyanate can be used particularly favorably.

The blending amount of the isocyanate compound is preferably 0.1 to 10% by mass in the adhesive excluding the solvent. By setting the blending amount within the above range, the reaction of the isocyanate compound does not become excessive or insufficient, an appropriate cohesive force can be imparted to the adhesive, the adhesive sheet can be suppressed from slipping or peeling during insert molding, and the molded product can be manufactured. It is possible to prevent the formation of bubbles when left in a moist heat environment. Further, the blending amount of the isocyanate compound is more preferably 0.5 to 5.0% by mass, and the adhesive force at the time of pressure-sensitive adhesion is enhanced, the displacement and peeling of the adhesive sheet at the time of insert molding are suppressed, and the environment is left in a moist heat. In order to suppress the formation of bubbles underneath, it is particularly preferably 1.0 to 3.0% by mass.

The adhesive includes ester solvents such as methyl acetate, ethyl acetate, propyl acetate and butyl acetate, which are usually used in adhesives, and ketone solvents such as acetone, methyl ketyl ketone, methyl isobutyl ketone, diisobutyl ketone and cyclohexanone. It is used by dissolving it in aromatic hydrocarbons such as toluene and xylene.

In addition to the above components, the adhesive includes a hydrolysis inhibitor such as carbodiimide, an adhesion accelerator, a surface conditioner, a leveling agent, a defoaming agent, a plasticizer, a tackifier resin, an antioxidant, an ultraviolet absorber, and the like. Additives such as thickeners can be used as needed. In addition, known catalysts, additives and the like can be used to regulate the cross-linking reaction.

The thickness of the adhesive may be any thickness as long as it can be attached to the surface of the decorative layer of the insert part and the adhesive sheet can be prevented from slipping or peeling during insert molding. In order to suppress the color difference between the coating resin and the adhesive sheet within the above preferable range, the thickness is preferably 5 to 30 μm, more preferably 10 to 20 μm.

[Adhesive sheet]
The adhesive sheet of the present invention has a structure in which the adhesive is provided in a layer on at least one surface of the base material. Further, the layer structure of the adhesive is not particularly limited, and the adhesive sheet may be an adhesive sheet composed of a single adhesive layer or an adhesive sheet composed of two or more layers of adhesive. Further, the adhesive sheet may have adhesive layers on both sides of the base material.

The adhesive sheet of the present invention preferably has a gel content of the adhesive layer in the range of 40 to 95% by mass, suppresses the formation of bubbles in a moist heat environment, and prevents the adhesive layer from being deformed during insert molding. It is more preferably in the range of 40 to 80% by mass, and more preferably in the range of 50 to 70% by mass in order to more reliably perform the above. Further, when the adhesive sheet is attached to a coated surface having a high surface hardness such as baking type acrylic coating, urethane coating, melamine coating, etc., the adhesive force at the time of pressure-sensitive adhesion is enhanced, and the adhesive sheet at the time of insert molding is further applied. The gel fraction is more preferably in the range of 55 to 95% by mass, preferably in the range of 70 to 90% by mass, in order to suppress slippage and peeling and to suppress the formation of bubbles in a moist heat-leaving environment. Is most preferable.

The adhesive sheet of the present invention is colorless and transparent without being decorated by the application of the base material and the adhesive described above, and the haze measured in accordance with JIS K7136 is 5.0% or less. Is preferable. When a base material colored in the same color as the coating resin is used, the color difference (ΔE) between the surface of the adhesive layer of the adhesive sheet and the coating resin is preferably 5.0 or less.

The thickness of the adhesive sheet may be any thickness as long as it can be attached to the surface of the decorative layer of the insert part and can prevent the adhesive sheet from slipping or peeling during insert molding. In order to ensure damage protection during insert molding and facilitate cutting of the adhesive sheet, the thickness is preferably 55 to 430 μm, more preferably 160 to 270 μm.

The adhesive sheet can be produced by a commonly used method. For example, it can be produced by forming an adhesive layer on a base material or a release liner. Specifically, the solution adhesive is directly applied to one side of the base material, dried or crosslinked, and the release-treated liner is attached, or once applied on the release liner, dried, and the adhesive is applied. After forming the layer, it can be produced by a method such as bonding to the base material, then heat curing and cross-linking.

The ball tack on the surface of the adhesive layer of the adhesive sheet is based on JIS Z0237. Measured by the Dow method, it is preferably less than 3 at 23 ° C. and 50% RH atmosphere. When the ball tack is in the above range, the surface of the adhesive layer of the adhesive sheet is less sticky at room temperature, and the insert parts are excellently aligned with the surface of the decorative layer and reattachable.

Further, the peeling adhesive force measured by the following measurement is preferably 0.1 N / 25 mm or more in the state at the time of pressure-sensitive adhesion, and 5 N / 25 mm or more in the state immediately before receiving heat damage. , More preferably 8N / 25mm or more. Within the above range, it is possible to prevent the adhesive sheet from slipping or peeling when the insert parts are set in the mold or when the insert is molded. The upper limit of the peeling adhesive force is not particularly limited, but in the preferred composition of the present invention, the upper limit is substantially about 30 N / 25 mm.

Further, the peeling adhesive force after receiving heat damage is preferably 10 N / 25 mm or more, and more preferably 20 N / 25 mm or more. Within the above range, it is possible to prevent the formation of bubbles due to the generation of gas when the insert-molded molded product is left in a moist heat environment.

The peeling adhesive force immediately after pressure-sensitive adhesion is measured by the following method. First, after peeling off the release liner from the adhesive sheet cut to a width of 25 mm and a length of 100 mm, a load of one reciprocation is applied to a polycarbonate plate on which aluminum is vapor-deposited on the surface with a 2 kg roller in an environment of 23 ° C. and 50% RH. Hang and paste. Within 1 minute after application, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance is measured.

The peeling adhesive strength immediately before receiving heat damage is measured by the following method. When the pressure-sensitive adhesive is laminated on the base material, first, the release liner is peeled off from the adhesive sheet cut into a width of 25 mm and a length of 100 mm, and then on the surface in an environment of 23 ° C. and 50% RH. It is attached to a polycarbonate plate on which aluminum is vapor-deposited by applying a load of one reciprocation with a 2 kg roller. After leaving it in an environment of 23 ° C. and 50% RH for 1 hour, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance is measured. ..

When the heat-sensitive adhesive is laminated on the base material, the release liner is peeled off from the adhesive sheet cut to a width of 25 mm and a length of 100 mm, and then on the surface in an environment of 23 ° C. and 50% RH. It is attached to a polycarbonate plate on which aluminum is vapor-deposited by applying a load of one reciprocation with a 2 kg roller. Next, the upper press plate of the hot press device is heated to 80 ° C. and hot pressed at a pressure of 0.1 MPa for 15 seconds. After leaving it in an environment of 23 ° C. and 50% RH for 1 hour, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance is measured. ..

The peeling adhesive force after receiving heat damage is added to the sample prepared above, and the upper press plate of the heat pressing device is heated to 200 ° C. and heat pressed at a pressure of 0.1 MPa for 15 seconds. After leaving it in an environment of 23 ° C. and 50% RH for 1 hour, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance is measured. ..

It is preferable to adjust the shape and size of the adhesive sheet according to the shape and diameter of the gate. Usually, in order to protect heat damage evenly, it is preferable to use a die-cut adhesive sheet having a shape equivalent to the shape of the gate. Further, the size of the adhesive sheet is preferably a diagonal length that is about 10 to 30 mm larger than the diameter of the gate. As a method of die-cutting the adhesive sheet, the adhesive sheet on which the release liner is laminated is mechanically cut with a flat pressure cutter or a rotary cutter equipped with a punching blade, or melted by a heat generator such as a laser. Examples thereof include a method of cutting to the above-mentioned shape and size by cutting or the like and removing unnecessary portions.

[Insert parts]
As an example of a preferred embodiment, the insert part to which the adhesive sheet is attached has a structure in which a translucent resin and a decorative layer are laminated as shown in the cross-sectional view of FIG. As an example of a method for manufacturing insert parts, printing ink is applied to the surface of a flat translucent resin plate having a thickness of about 1 to 5 mm by a printing method such as silk screen printing or gravure printing to have a thickness of about 1 to 20 μm. Examples thereof include a method of manufacturing insert parts by laminating decorative layers and then thermally deforming them with a heat press machine or the like. As another method, a decorative film is set in the mold, the translucent resin described later is melted and inserted into the mold, and an insert part in which the translucent resin and the decorative film are integrated is produced. Can also be mentioned. After molding the plate of the translucent resin, the decorative layer may be laminated by the above method or the like.

Further, a metal such as silver, aluminum, or indium is laminated on the surface of the translucent resin plate or the surface of the printing layer to a thickness of about 0.01 to 2 μm by vacuum deposition, plating, or the like, and then molded in the same manner as described above. There is also a method of doing so. In order to improve the adhesion to the adhesive sheet and the coating resin, an undercoat layer such as an ultraviolet curable type or a thermosetting type may be provided on the surface of the metal layer.

The insert parts obtained above are excellent in decorativeness and can be suitably used for laminating the adhesive sheet of the present invention on the surface of the decorative layer. As an example of a suitable embodiment, the cross-sectional view of FIG. 3 shows. As shown, it is possible to protect the coating resin from damage such as distortion and displacement of the translucent resin and the decorative layer due to heat when the coating resin is melted and injected from the gate. Further, even if the completed molded product is left in a moist heat environment, it is effective in preventing the formation of bubbles due to the gas that may be generated from the surface of the insert part, the coating resin, or the base material of the adhesive sheet.

[Translucent resin]
Any transparent resin can be used as the translucent resin used for the insert part. There is no particular limitation as long as it is transparent, but it is not particularly limited, but polycarbonate resin, polymethylmethacrylate resin and other acrylic resins, polypropylene resins, polystyrene resins, polyacrylic copolymer resins, polyolefin resins, acrylonitrile / butadiene / styrene resins, polyesters. Amino resins such as resins, epoxy resins, polyurethane resins, polyimide resins, polyamideimide resins, silicone resins, melamine resins, allyl resins, furan resins, phenolic resins, fluororesins, polyarylate resins, Polyallyl sulfone resin, polyether sulfone resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, or a composite resin thereof can be used. From the viewpoint of transparency and ease of molding, polycarbonate resin and polymethyl It is preferable to use a thermoplastic resin such as methacrylate and other acrylic resins.

The translucent resin preferably has a total light transmittance Tt of 80 to 99% and a haze of 0 to 5% in terms of the thickness used. The total light transmittance Tt is 90 to 99%, and the haze is more preferably 0 to 3%. By having the total light transmittance Tt and haze in the above range, the color of the decorative layer does not change to the surface of the translucent resin, and the design is not impaired. However, in order to suppress the reflection of sunlight, fluorescent lamps, etc., an antireflection layer is provided on the surface side where the decorative layer of the translucent resin or the coating resin is not laminated, or the color of the decorative layer is intentionally changed. Therefore, haze may be imparted to the inside of the translucent resin.

The surface of the translucent resin is subjected to surface unevenness treatment, corona discharge treatment, chromic acid treatment, flame treatment, etc. by sandblasting method, solvent treatment method, etc. for the purpose of improving adhesion to the decorative layer and coating resin. Surface treatment such as hot air treatment and ozone / ultraviolet irradiation treatment may be performed. Further, an undercoat layer such as an ultraviolet curable type or a thermosetting type may be provided on the surface of the translucent resin.

The thickness of the translucent resin is preferably 0.1 to 5 mm, more preferably 1 to 3 μm. Within the thickness range, the surface of the decorative layer can be effectively protected, and the color of the decorative layer does not change to the surface of the translucent resin, so that the design is not impaired.

[Coating resin]
Examples of the coating resin include polycarbonate, polymethylmethacrylate, polystyrene, polypropylene, acrylonitrile / butadiene / styrene copolymer, acrylonitrile / styrene copolymer, acrylonitrile / styrene / acrylic copolymer, and acrylonitrile / ethylene / propylene / diene / styrene. Copolymer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, polymethylpentene, polyether ether ketone, polyether sulfone, poly Examples thereof include etherimide, polyimide, fluororesin, nylon and the like. Among them, acrylonitrile, which can be melted at a temperature of about 200 ° C. and has excellent fluidity at the time of melting, is preferably used, and is excellent in flexibility and impact resistance. Most preferably, a butadiene / styrene copolymer or an acrylonitrile / ethylene / propylene / diene / styrene copolymer is used.

The coating resin is an organic pigment, an inorganic pigment, a colorant such as a masterbatch or a dry color in which a pigment is kneaded, an antioxidant, an antioxidant, a lubricant, an ultraviolet absorber or a light stabilizer, and an inorganic substance for improving strength. A filler or the like may be added. As the colorant, it is desirable to use a black colorant in order to enhance the design of the decorative layer.

[Article]
As an article in which the adhesive sheet is preferably used, as an example of a preferred embodiment, as shown in the cross-sectional view of FIG. 4, the insert part including the translucent resin and the decorative layer, the adhesive sheet, and the said adhesive sheet. Examples thereof include articles in which coating resins are laminated in this order.

The article is decorated with the surface of the translucent resin to prepare an insert part [1], and a surface having an adhesive layer of an adhesive sheet is provided at a place where a gate on the surface of the decorative layer approaches. Step of bonding [2], a process of setting a structure in which insert parts and adhesive sheets are laminated in order on a mold, injecting molten resin from a gate onto the surface of the adhesive sheet, and coating the insert parts and the adhesive sheet. Examples thereof include articles produced by a step including [3] in order. Two or more insert parts, adhesive sheets, and coating resins may be used at the same time.

The step [1] is manufactured according to the method for manufacturing the insert part.

The step [2] is preferably performed in an environment of 10 to 40 ° C. at room temperature for reattaching and positioning the adhesive sheet. The adhesive sheet is preferably attached so that the center of the adhesive sheet is at the position of the gate opening, and it may be a work by personnel or a mechanical attachment by an automatic labeler or the like. When the adhesive layer of the adhesive sheet is slightly adhesive and has heat-sensitive adhesiveness, it is preferable to further perform a heating step of about 60 to 100 ° C. for about 10 to 30 seconds after the step [2]. The heating step may be performed without pressurization, or may be heated while being pressurized by a heat press device or the like.

In the step [3], the coating resin is heated and melted until fluidity is obtained according to the melting temperature of the coating resin, and is injected from the gate of the insert molding machine to coat the surface of the insert part and the surface of the adhesive sheet.

The article obtained by the above-mentioned manufacturing method is suitably used for a molded product having a design, such as an ornament or a logo mark used for the exterior of a home electric appliance, the interior / exterior of an automobile, or the like. It is a three-dimensional molded product in which the insert parts are coated with a coating resin, and when these molded products are manufactured by insert molding, the coating resin is melted on the surface of the decorative layer and is transparent due to heat when injected from the gate. Prevents damage such as distortion and displacement due to deformation of the photoresin and decorative layer, and is generated from the translucent resin, coating resin, or the base material of the adhesive sheet even after the finished molded product is left in a moist heat environment. Since the design can be maintained for a long period of time by suppressing the possible gas, it is a molded product having a design used for the exterior of home appliances, the interior and exterior of automobiles, and the like.

The present disclosure is not limited to the above embodiment. The embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and exhibiting the same effect and effect is described in the present invention. Included in the technical scope of the disclosure.

<Preparation of base material (a1)>
Acrylonitrile-butadiene-styrene copolymer resin pellets (Toyorac 600-309, manufactured by Toray Co., Ltd.) containing 6% by mass of black masterbatch (SMF-TT1608, carbon black content 50% by mass, manufactured by Regino Color Industry Co., Ltd.) It was melted and extruded from the die to produce a 0.25 mm thick black substrate through a calendaring machine equipped with a glossy metal roll and a matte rubber roll. Further, the surface side in contact with the glossy metal roll was corona-treated until the surface tension became 52 mN / m to prepare a black base material (a1).

<Preparation of base material (a2)>
A base material (a2) having a thickness of 0.15 mm was produced in the same manner as the base material (a1) except that the thickness was 0.15 mm.

<Preparation of adhesive composition (b1)>
Byron BX10SS (solid content 30% by mass, number average molecular weight 21,000, glass transition temperature -18 ° C, manufactured by Toyo Boseki Co., Ltd.) 70.7 parts by mass as polyester resin, and Byron UR1350 (solid content 33% by mass) as polyester urethane resin , Number average molecular weight 36,000, glass transition temperature 46 ° C., manufactured by Toyo Boseki Co., Ltd.) 29.3 parts by mass were mixed. To 100 parts by mass of this composition, 0.45 parts by mass of Vernock DN980 (solid content 75% by mass, hexamethylene diisocyanate type, manufactured by DIC Corporation) was added as an isocyanate compound, stirred for 10 minutes, and left for 1 hour to remove bubbles. The mixture was allowed to obtain an adhesive composition (b1).

<Preparation of adhesive composition (b2)>
Byron A516 (solid content 30% by mass, number average molecular weight 28,000, glass transition temperature -15 ° C, manufactured by Toyo Boseki Co., Ltd.) 81 parts by mass as polyester resin, and Byron UR1400 (solid content 30% by mass, number) as polyester urethane resin An average molecular weight of 40,000, a glass transition temperature of 83 ° C., and 19 parts by mass of Toyo Boseki Co., Ltd.) were mixed. To 100 parts by mass of this composition, 0.40 parts by mass of Vernock DN980 (solid content 75% by mass, hexamethylene diisocyanate type, manufactured by DIC Corporation) was added as an isocyanate compound, stirred for 10 minutes, and left for 1 hour to remove bubbles. The mixture was allowed to obtain an adhesive composition (b2).

<Preparation of adhesive composition (b3)>
Byron BX10SS (solid content 30% by mass, number average molecular weight 21,000, glass transition temperature -18 ° C, manufactured by Toyo Boseki Co., Ltd.) as a polyester resin in 100 parts by mass, and Vernock DN980 (solid content 75% by mass, hexamethylene) as an isocyanate compound. Diisocyanate type, manufactured by DIC Co., Ltd.) 0.40 parts by mass was added, and the mixture was stirred for 10 minutes and then left for 1 hour to allow bubbles to escape to obtain an adhesive composition (b3).

<Preparation of adhesive composition (b4)>
In a reaction vessel equipped with a stirrer, a reflux cooling tube, and a thermometer, 94.3 parts by mass of polypropylene glycol (number average molecular weight; 1,000), 0.3 parts by mass of 2-hydroxyethyl acrylate, and 1,4-hexane. 19.5 parts by mass of dimethanol, 0.5 parts by mass of 2,6-ditershaributyl cresol, 0.1 parts by mass of p-methoxyphenol, and 57.4 parts by mass of ethyl acetate were added.
After raising the temperature in the reaction vessel to 40 ° C., 50.3 parts by mass of isophorone diisocyanate was added.
Next, 0.01 part by mass of dioctyltin dineodecato was added, the temperature was raised to 75 ° C. over 1 hour, held at 75 ° C. for 12 hours, and then 51.7 parts by mass of ethyl acetate was added to 30 parts. A urethane resin composition was obtained by stirring and cooling until the mixture became uniform for 1 minute.
20 parts by mass of trimethylolpropane triacrylate (“Aronix M-309” manufactured by Toa Synthetic Co., Ltd.) and 1-hydroxy-cyclohexyl-phenyl-ketone (IGM Resin B.) with respect to 100 parts by mass of the solid content of the urethane resin composition. Omnirad 184) manufactured by V., 1.0 part by mass, bisdecanoate (2,2,6,6-tetramethyl-1- (octyloxy) -4-piperidinyl) ester, 0.5 part by mass, tri 0.5 parts by mass of phenylphosphine was sequentially added and stirred with a stirrer until uniform to obtain an adhesive composition (b4) in which a urethane resin and an acrylic monomer were mixed.

<Preparation of adhesive composition (b5)>
As a polyester resin, 40 parts by mass of Byron 200 (solid content 100% by mass, number average molecular weight 17,000, glass transition temperature 67 ° C., manufactured by Toyobo Co., Ltd.) was dissolved in 60 parts by mass of methyl ethyl ketone. Polyester urethane resin was not mixed. To 100 parts by mass of this composition, 1.6 parts by mass of Vernock DN980 (hexamethylene diisocyanate type, manufactured by DIC Corporation) was added as an isocyanate compound, and the mixture was stirred for 10 minutes and then left to stand for 1 hour to allow bubbles to escape to form an adhesive composition. (B5) was obtained.

<Preparation of adhesive composition (b6)>
The adhesive composition (b6) is the same as the adhesive composition (b1) except that the Burnock DN980 is changed from 0.45 parts by mass to 0.15 parts by mass in the adhesive composition (b1). Got

<Preparation of adhesive composition (b7)>
Byron BX10SS (solid content 30% by mass, number average molecular weight 21,000, glass transition temperature -18 ° C, manufactured by Toyo Boseki Co., Ltd.) 69 parts by mass as polyester resin, and Byron UR3200 (solid content 30% by mass, number) as polyester urethane resin An average molecular weight of 40,000, a glass transition temperature of -3 ° C., and 31 parts by mass of Toyo Boseki Co., Ltd. were mixed. 100 parts by mass of this composition, 0.45 parts by mass of Elastostab H01 (manufactured by Nisshinbo Chemical Co., Ltd.) as a hydrolysis inhibitor and Vernock DN980 (solid content 75% by mass, hexamethylene diisocyanate type, manufactured by DIC Co., Ltd.) as an isocyanate compound. After adding 1.7 parts by mass and stirring for 10 minutes, the mixture was left to stand for 1 hour to allow bubbles to escape to obtain an adhesive composition (b7).

<Preparation of adhesive composition (b8)>
In a reaction vessel equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, and a thermometer, 68 parts by mass of n-butyl acrylate, 20 parts by mass of methyl acrylate, 10 parts by mass of methyl methacrylate, 2 parts by mass of 2-hydroxyethyl acrylate, and acetic acid. 122 parts by mass of ethyl was charged, and the temperature was raised to 80 ° C. while stirring and blowing nitrogen. Then, 2 parts by mass (5% by mass of solid content) of the azobisisobutyronitrile solution previously dissolved in ethyl acetate was added. Then, after holding at 80 ° C. for 8 hours under stirring, the contents were cooled and filtered through a 200 mesh wire mesh, and the non-volatile content was 45% by mass, the viscosity was 6000 mPa · s, the glass transition temperature was −32 ° C., and the weight average molecular weight was 70. An acrylic copolymer of 10,000 was obtained. 100 parts by mass of acrylic copolymer (45% by mass of non-volatile content), 0.6 parts by mass of Vernock DN980 (solid content 75% by mass, hexamethylene diisocyanate type, manufactured by DIC Co., Ltd.), 1.0 part by mass of acetylacetone as an isocyanate compound. Add 1.0 part by mass of Chrisbon Accelerator T-81E (solid content 1% by mass, organic tin compound, manufactured by DIC Co., Ltd.) as a cross-linking accelerator, stir for 10 minutes, and leave it for 1 hour to allow bubbles to escape. , An adhesive composition (b8) was obtained.

(Example 1)
The adhesive composition (b1) is dried on a release-treated surface of a polyester-based release liner TN100-50 (non-silicone release liner manufactured by Toyo Boseki Co., Ltd.) using a rod-shaped metal applicator. After that, the coating was applied so that the thickness was 20 μm, and the mixture was placed in a dryer at 90 ° C. for 3 minutes to dry. Then, the base material (a1) was bonded to the corona-treated surface. Then, it was left at 40 degreeC for 3 days to obtain an adhesive sheet (c1).

(Example 2)
An adhesive sheet (c2) was obtained in the same manner as in Example 1 except that the base material (a2) was used.

(Example 3)
One side of a commercially available transparent polystyrene sheet with a thickness of 50 μm (OPS film GM manufactured by Asahi Kasei Chemicals Co., Ltd.) was subjected to corona treatment so that the surface tension was 52 mN / m, and this was carried out except that it was used as a base material. An adhesive sheet (c3) was obtained in the same manner as in Example 1.

(Example 4)
An adhesive sheet (c4) was obtained in the same manner as in Example 1 except that the adhesive composition (b2) was used.

(Example 5)
An adhesive sheet (c5) was obtained in the same manner as in Example 1 except that the adhesive composition (b3) was used.

(Example 6)
The adhesive composition (b4) is dried on a release-treated surface of a polyester-based release liner TN100-50 (non-silicone release liner manufactured by Toyo Boseki Co., Ltd.) using a rod-shaped metal applicator. After that, the coating was applied so that the thickness was 20 μm, and the mixture was placed in a dryer at 90 ° C. for 3 minutes to dry. Then, the base material (a1) was bonded to the corona-treated surface. ^{Then, with a metal halide lamp, ultraviolet rays having an integrated light intensity of 500 mJ / cm 2} were applied from the release liner surface of the polyester base material to crosslink the particles to obtain an adhesive sheet (c6).

(Example 7)
An adhesive sheet (c10) was obtained in the same manner as in Example 1 except that the adhesive composition (b7) was used.

(Example 8)
An adhesive sheet (c11) was obtained in the same manner as in Example 1 except that the adhesive composition (b8) was used.

(Comparative Example 1)
The adhesive was not laminated on the base material (a1) and was used as it was for evaluation.

(Comparative Example 2)
An adhesive sheet (c7) was obtained in the same manner as in Example 1 except that the adhesive composition (b5) was used.

(Comparative Example 3)
The release liner on one side of the acrylic pressure-sensitive adhesive tape (ZB7011W manufactured by DIC Corporation, thickness 25 μm) is removed and bonded to the corona-treated surface of the base material (a1), and the adhesive sheet (c8) is attached. Obtained.

(Comparative Example 4)
An adhesive sheet (c9) was obtained in the same manner as in Example 1 except that the adhesive composition (b6) was used.

(Making insert parts)
An ultraviolet curable undercoat layer (Toyo) using a Mayer bar as an undercoat layer on the surface of a transparent polycarbonate resin sheet ("Polyca Ace ECK100UU" manufactured by Sumitomo Bakelite Co., Ltd.) with a thickness of 3 mm and a length of 100 mm on each side. UV-270M manufactured by Kogyo Paint Co., Ltd.) was applied to a thickness of 2 μm, and cured by irradiating with an ultraviolet ray at an intensity of ^{500 mJ / cm 2 with a metal halide lamp.} Then, aluminum was vacuum-deposited on the surface of the coat layer so as to have a thickness of 0.2 μm to obtain insert parts.

(Tensile storage modulus _{(E '25), (E} ' 85), (E '200) and loss tangent (tan [delta))
The adhesive composition used in Examples and Comparative Examples was applied to a release liner, dried, and then the adhesive layer obtained without bonding to the base material was laminated to a thickness of 400 μm and left at 40 ° C. for 3 days. Then, test pieces of the adhesive layer of Examples and Comparative Examples were prepared. The test piece was cut into a rectangular shape with a width of 5 mm and a length of the measuring part of 20 mm, and the lengths of the handles at both ends were cut into 15 mm each, and a dynamic viscoelasticity tester (manufactured by TA Instruments). Using a viscoelasticity measuring machine "RSA III"), in tensile mode, under the conditions of frequency 3 Hz, temperature rise rate 5 ° C / min, load strain 0.1-0.6%, temperature from -20 to 210 ° C. The tensile storage elastic modulus E'and the loss tangent tan δ in the region were measured. 25 ℃, 85 ℃, each tensile storage modulus of _{200 ℃ (E '25),} (E' was _{85), (E '200)} . In Comparative Example 1, the base material (a1) was regarded as the same as the adhesive layer, and the tensile storage elastic modulus and the loss tangent of the base material (a1) were measured.

(Gel fraction)
The adhesive composition used in Examples and Comparative Examples was applied to a release liner, dried, and then another lightly peelable release liner (manufactured by Fujimori Kogyo Co., Ltd., 38E-0010BD) without being bonded to the base material. ), Left at 40 ° C. for 3 days, the obtained adhesive layer was cut into a size of 40 mm × 50 mm, and then only the lightly peelable release liner was removed to obtain a test piece. After measuring the mass of the test piece, it was immersed in toluene adjusted to 23 ° C. for 24 hours.
After the immersion, the test piece was taken out and dried in a dryer at 105 ° C. for 1 hour, and the mass was measured. The gel fraction of the adhesive layer was calculated based on the above mass and the following formula.

Gel fraction (% by mass) of the adhesive layer = {(mass of the adhesive layer of the adhesive sheet remaining without being dissolved in toluene) / (mass of the adhesive layer of the adhesive sheet before immersion in toluene)} x 100

The mass of the adhesive layer of the adhesive sheet before immersion refers to a value obtained by subtracting the mass of the release liner used for manufacturing the test piece from the mass of the test piece. The mass of the remaining adhesive layer refers to a value obtained by subtracting the mass of the release liner from the mass of the residue after drying.

(Adhesive fixation of adhesive sheet)
The release liner was peeled off from the adhesive sheets of Examples and Comparative Examples cut into a circle with a diameter of 30 mm on the aluminum-deposited surface of the insert part, and reciprocated once with a 2 kg roller in an environment of 23 ° C. and 50% RH. It was pressed and attached, and only the upper press plate of the heat pressing device was heated to 80 ° C. and heated at a pressure of 0.1 MPa for 15 seconds to adhere. The adhesive fixation of the adhesive sheet as a heat damage protective layer was evaluated according to the following criteria. As a heat press device, a heat press machine "TP-750 Air Press" manufactured by Tester Sangyo Co., Ltd. was used.
◯: The adhesive sheet adhered firmly, and the adhesive sheet did not easily fall off even when leaning against it.
Δ: The adhesive sheet peeled off when touched by hand, but the adhesive sheet did not easily fall off even when leaned against it.
X: The adhesive sheet did not adhere, and the adhesive sheet fell off when leaned against it.

(Heat damage protection)
On the test piece produced by the adhesive fixing property of the adhesive sheet, the glossy surface of an aluminum foil (manufactured by UACJ Co., Ltd., My Foil) having a thickness of 11 μm is placed on the surface side of the adhesive sheet to prevent adhesion to the heat press device. Next, only the upper press plate of the heat press machine was heated to 200 ° C., pressed against the adhesive sheet, and pressed at a pressure of 0.1 MPa for 15 seconds to cause heat damage. As a heat damage protection property, visual observation was performed from the surface side of the polycarbonate plate to which the adhesive sheet was not attached, and the presence or absence of air bubbles between the insert part and the adhesive sheet and the presence or absence of imprints were confirmed according to the following criteria. As the heat press device, the same device as described above was used.
⊚: No bubbles were generated and no imprints were seen.
◯: No bubbles were generated, but very few imprints were observed.
Δ: Bubbles were generated, and very few imprints were observed.
X: Bubbles were generated, and imprints were also strongly observed.

(Foam resistance after leaving in moist heat)
After the sticking material obtained by the evaluation of the heat damage protection property was left to stand in an environment of a temperature of 85 ° C. and a humidity of 85% RH for 200 hours, air bubbles between the insert part and the adhesive sheet from the surface side of the polycarbonate plate of the insert part. The presence or absence of the adhesive and the appearance of the sticker were evaluated according to the following criteria.
◯: There were no bubbles at all.
Δ: There were very few fine bubbles, but the level was not a problem.
X: There were bubbles.

(Peeling adhesive strength)
The adhesive sheets produced in Examples and Comparative Examples were cut into a size of 25 mm in width and 100 mm in length, the release liner was peeled off, and then the aluminum-deposited surface of the insert part was subjected to an environment of 23 ° C. and 50% RH. A load of one reciprocation was applied to the side with a 2 kg roller to attach it, and pressure-sensitive adhesion was performed. Within 1 minute of application, use a Tencilon type tensile tester (A & D Co., Ltd., RTG-1210) to apply the adhesive sheet in the 180 ° direction at a tensile speed of 300 mm / min from the aluminum-deposited surface to the adhesive sheet. Was peeled off, and the peeling resistance force immediately after pressure-sensitive adhesion was measured.

Further, an adhesive sheet is attached to the aluminum-deposited surface in the same manner as described above, and then only the upper press plate of the heat pressing device is heated to 80 ° C. and heat-pressed at a pressure of 0.1 MPa for 15 seconds for heat-sensitive adhesion. I let you. After leaving it in an environment of 23 ° C. and 50% RH for 1 hour, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance after heat-sensitive bonding. The force was measured. As the heat press device, the same device as described above was used.

Further, an adhesive sheet is attached to the aluminum vapor deposition surface in the same manner as described above, and after the heat pressing at 80 ° C., a gloss of an aluminum foil (manufactured by UACJ Co., Ltd., My Foil) having a thickness of 11 μm is used to prevent adhesion to the heat pressing device. The surface was covered so as to be on the surface side of the adhesive sheet, and only the upper press plate of the heat pressing device was heated to 200 ° C. and heat pressed at a pressure of 0.1 MPa for 15 seconds to cause heat damage. After leaving it in an environment of 23 ° C. and 50% RH for 1 hour, the adhesive sheet is peeled off from the vapor-deposited surface of aluminum in the 180 ° direction at a tensile speed of 300 mm / min with a Tencilon type tensile tester, and the peeling resistance after heat damage. The force was measured.

(Color difference between adhesive sheet and coating resin)
Examples and Comparative Examples except Example 3 cut into a circle with a diameter of 30 mm on the central surface of a square release film (Opuran X-88B, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) having a thickness of 50 μm and a side length of 150 mm. Adhesive sheet was attached. The lower press plate of the heat press device was heated to 200 ° C., and another square release film having a thickness of 50 μm and a side length of 150 mm was placed on the lower press plate. Acrylonitrile-butadiene-styrene copolymer resin pellets (Toyorac 600-309, Toray Co., Ltd.) to which 6% by mass of black masterbatch (SMF-TT1608, carbon black content 50% by mass, manufactured by Regino Color Industry Co., Ltd.) was added. 50 g (manufactured by the company) was placed and heated and melted. On it, the base material side of the adhesive sheet attached to the release film is allowed to stand on the molten resin side, and the pressure is applied at a pressure of 2 MPa for 30 seconds to adhere to a coating resin having a thickness of about 2 mm and a diameter of about 10 cm. A laminate of sheets was made. The release film was peeled off from the obtained laminate, and the color difference was measured from the adhesive layer surface of the adhesive sheet using the coating resin on the release surface side as a reference color. A spectrophotometer (CM-5, manufactured by Konica Minolta Co., Ltd.) was used for the measurement, and the measurement was performed in a CIE1976-compliant L * a * b color space coordinate system at a reflection angle of 2 °.

(Haze of adhesive sheet)
For the adhesive sheet of Example 3, the release liner was removed and the haze was measured. For the haze measurement, "HR-100 type" manufactured by Murakami Color Technology Research Institute Co., Ltd. was used.

(Discoloration resistance of aluminum vapor deposition layer)
After the affix obtained by the evaluation of heat protection was left to stand in an environment of a temperature of 85 ° C. and a humidity of 85% RH for 500 hours, the discoloration resistance of the aluminum-deposited surface from the surface side of the polycarbonate plate of the insert part was described below. Visual evaluation was performed based on the standard.
◯: Compared with the appearance of the aluminum-deposited surface before being left to stand, there was no discoloration.
Δ: There was a slight discoloration of the aluminum-deposited surface as compared with the appearance of the aluminum-deposited surface before it was left to stand, but it was at a level that was not a problem.
X: Compared with the appearance of the aluminum-deposited surface before being left to stand, the aluminum-deposited surface was discolored.

The adhesive sheets of Examples 1 to 8 are simple as an adhesive sheet that protects from heat damage (200 ° C.) when the coating resin is injected into the decorative layer of the insert part without being easily dropped or displaced. It was possible to protect the decorative layer by accurately adhering and fixing it to a place to be protected from heat damage, and to prevent foaming derived from the base material of the decorative layer and the adhesive sheet after being left in a moist heat. On the other hand, since the adhesive sheet of Comparative Example 1 easily fell off, it was not possible to accurately bond and fix the decorative layer. In Comparative Examples 2 to 4, although the adhesive sheet did not fall off, the protection against heat damage was inferior, and foaming could not be prevented after being left in a moist heat.

Further, among Examples 1 to 8, the adhesive sheet of Example 8 does not cause discoloration of the aluminum-deposited surface in a moist heat environment as compared with the adhesive sheet of Examples 1 to 7, and is protected by the generation of air bubbles. In addition to preventing the occurrence of swelling between the film and the decorative layer and preventing the deformation of the adhesive layer during insert molding, the effect of preventing the metal layer, which is the decorative layer, from fading in a moist heat environment was confirmed. In the adhesive sheet of Example 7, the adhesive composition (b7) contained a hydrolysis inhibitor, and the discoloration resistance evaluation of the vapor-deposited layer was Δ. However, when the hydrolysis inhibitor was not added, the adhesive sheet was resistant to discoloration. The discoloration evaluation was x.

1 ... Base material 2 ... Adhesive 3 ... Translucent resin 4 ... Decorative layer 5 ... Adhesive sheet 6 ... Gate 7 ... Coating resin

Claims (9)

An adhesive sheet used for insert molding that coats the surface of the decorative layer by injecting and applying molten resin to the surface of the decorative layer after being attached to the surface of the decorative layer of the insert part.
An adhesive sheet having an adhesive layer in which a pressure-sensitive adhesive or a heat-sensitive adhesive is laminated on at least one surface of the base material of the adhesive sheet.
_{The adhesive layer has a tensile storage elastic modulus (E'85} ) measured at a frequency of 3 Hz in an atmosphere of a temperature of 85 ° C. in the range of 1 × 10 ⁵ to 1 × 10 ⁸ Pa, and has a temperature of 200 ° C. an adhesive layer measured tensile storage modulus at a frequency 3Hz (E _'200) is in the range of ^{1 × 10 5 ~1 × 10 7} Pa in the atmosphere, and the tensile loss modulus measured at a frequency 3Hz An adhesive sheet having an adhesive layer having a loss positive contact (tan δ) obtained by dividing the rate by the tensile storage elastic modulus of 0.8 or less in a temperature range of 60 to 200 ° C. The adhesive sheet is not decorated and
The adhesive sheet according to claim 1, wherein the haze of the adhesive sheet is colorless and transparent with a haze of 5.0% or less, or the color difference (ΔE) between the surface of the adhesive layer of the adhesive sheet and the coating resin is 5.0 or less. The adhesive sheet according to claim 1 or 2, wherein the gel fraction of the adhesive layer is in the range of 40 to 95% by mass. The adhesive sheet according to any one of claims 1 to 3, wherein the adhesive layer of the adhesive sheet is composed of a compound containing a polyester resin and a polyester urethane resin and is crosslinked with an isocyanate compound. Claims 1 to 1, wherein the adhesive layer of the adhesive sheet is formed of a resin having no ester bond in the main chain and an adhesive containing a cross-linking agent, and the resin having no ester bond in the main chain is cross-linked. The adhesive sheet according to any one of 3. The adhesive sheet according to any one of claims 1 to 5, wherein the base material of the adhesive sheet is a styrene-based polymer or a styrene-based copolymer. The adhesive sheet according to any one of claims 1 to 6, wherein the thickness of the base material of the adhesive sheet is in the range of 50 to 2000 μm. An article in which an insert part including a translucent resin and a decorative layer, an adhesive sheet according to any one of claims 1 to 7, and a coating resin are laminated in this order. The step of decorating the surface of the translucent resin to produce an insert part [1], to any one of claims 1 to 7 to a position where the molten resin is directly injected from at least the gate on the surface of the decorative layer. The step of laminating the surfaces of the adhesive sheet having the adhesive layer [2], the insert parts, and the structure in which the adhesive sheet is laminated in this order are set in the mold, and the molten resin is injected from the gate onto the surface of the adhesive sheet. A method for manufacturing an article, which comprises a step [3] of coating the insert part and the adhesive sheet in order.

Images