JP5060648B1 - Transfer sheet and transfer sheet manufacturing method - Google Patents

Abstract

（式中のＲは、エポキシ基、ビニル基、メタクリル基、メルカプト基、スチリル基のいずれかを少なくとも１以上含むアルキル直鎖であり、Ｄは、ＯＭｅ、ＯＥｔ、ＯＥｔＯＭｅ、ＯＥｔＯＥｔのいずれか１つであり、Ｍｅはメチル基、Ｅｔはエチル基を示す。）
【選択図】なしProvided is a transfer sheet capable of preventing peeling between protective layers in a transfer sheet in which a plurality of protective layers are laminated, and a method for manufacturing the transfer sheet.
A first protective layer formed on a base sheet and a second protective layer formed on the first protective layer, wherein at least one of the first protective layer and the second protective layer is provided. On the other hand, a silane coupling agent of the following formula having a molecular weight of 100 to 500 was added to adhere both layers.
[Chemical 1]

(In the formula, R is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. Me represents a methyl group, and Et represents an ethyl group.)
[Selection figure] None

Description

  The present invention relates to a transfer sheet used when a resin layer or a picture layer laminated on one side of a base sheet is transferred to the surface of an article.

  2. Description of the Related Art Conventionally, a method for protecting or decorating the surface of an article such as a plastic part or an exterior product using a transfer sheet is known. The transfer sheet has a structure in which a transfer layer is provided on one side of a base sheet as a support, and this transfer layer is transferred from the base sheet to the surface of the article. The transfer layer transferred to the surface of the article is a laminate in which a resin, a design, etc. (protective layer) is laminated, and forms a protective coating or a decorative coating on the article surface.

  For example, Patent Document 1 discloses a transfer sheet in which an anchor layer and a hard coat layer are laminated on a base sheet side adjacent to a metal thin film. The anchor layer adjacent to the metal thin film has a role of improving the corrosion resistance by protecting the metal thin film from scratches and the like together with the hard coat layer.

JP 2010-82963 A

  In the transfer sheet of Patent Document 1, two protective layers, an anchor layer and a hard coat layer, are formed on a metal thin film. In such a transfer sheet, when only the base sheet is peeled off after being attached to the transfer object, peeling may occur between the hard coat layer and the anchor layer. This can also occur when the anchor layer and the hard coat layer are formed by a printing method in order to make the transfer layer into a thin film. As the cause, when forming the anchor layer on the hard coat layer, it is considered that the adhesion between the hard coat layer and the anchor layer is reduced by forming the anchor layer after drying the hard coat layer. .

  An object of the present invention is to provide a transfer sheet and a transfer sheet manufacturing method capable of preventing peeling between protective layers in a transfer sheet in which a plurality of protective layers are laminated.

ここで、式中のＲは、エポキシ基、ビニル基、メタクリル基、メルカプト基、スチリル基のいずれかを少なくとも１以上含むアルキル直鎖であり、Ｄは、ＯＭｅ、ＯＥｔ、ＯＥｔＯＭｅ、ＯＥｔＯＥｔのいずれか１つであり、Ｍｅはメチル基、Ｅｔはエチル基を示す。 A first characteristic configuration of the transfer sheet of the present invention includes a base sheet, a first protective layer formed on the base sheet, and a second protective layer formed on the first protective layer. The first protective layer and the second protective layer are both hard coat layers for protecting the surface of the transferred product, and the hard coat layers constituting the first protective layer and the second protective layer are mainly acrylate. As a component, a silane coupling agent represented by the following formula having a molecular weight of 100 to 500 is added to at least one of the first protective layer and the second protective layer, and both layers are adhered to each other It is in.

Here, R in the formula is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. 1, Me represents a methyl group, and Et represents an ethyl group.

  As in this configuration, when a silane coupling agent having a molecular weight of 100 to 500 is added to at least one of the first protective layer and the second protective layer and both layers are adhered, the silane coupling agent is added. In the protective layer thus formed, the silane coupling agent reacts with the resin material in the protective layer. The reactant comes into contact with the resin constituting the other adjacent protective layer, and the interaction between the reactant and the resin improves the adhesion between the first protective layer and the second protective layer. As a result, delamination between the first protective layer and the second protective layer in the transfer sheet can be prevented.

  Moreover, the hardness of the said protective layer improves because the cohesion force of the protective layer to which the silane coupling agent was added improves. As a result, the hardness of the entire protective layer is improved.

Further, in the first characterizing feature, Ri hard coat layer der that the first protective layer and the second protective layer to protect the both surface of the transfer article, constituting the first protective layer and the second protective layer Both of the hard coat layers to be made mainly contain acrylate .

  With this configuration, the adhesion between the hard coat layers is improved, and the hardness of the entire hard coat layer is high.

The second characteristic configuration of the transfer sheet of the present invention is that both the first protective layer and the hard coat layer constituting the second protective layer are mainly composed of a varnish containing glycidyl methacrylate and methyl methacrylate .

The 3rd characteristic structure of the transfer sheet of this invention exists in the point whose addition amount of the said silane coupling agent is 0.5-5.0 w% of the resin component in the protective layer which concerns on the said addition.

When the addition amount of the silane coupling agent is less than 0.5 w% of the resin component in the protective layer according to the addition, the adhesion between the first protective layer and the second protective layer is hardly improved.
On the other hand, when the addition amount of the silane coupling agent exceeds 5.0 w%, the protective layer according to the addition is gelled, so that the first protective layer and the second protective layer cannot be appropriately laminated. .
In view of the above points, the amount of the silane coupling agent added is preferably 0.5 to 5.0 w% of the resin component in the protective layer according to the addition.

The 4th characteristic structure of the transfer sheet of this invention exists in the point whose thickness of the protective layer to which the said silane coupling agent is added is 0.5-5 micrometers.

When the thickness of the protective layer to which the silane coupling agent is added is less than 0.5 μm, the wear resistance and chemical resistance of the protective layer are weakened.
On the other hand, if the thickness of the protective layer to which the silane coupling agent is added exceeds 5 μm, the cost becomes high, and the transfer sheet becomes unsatisfactory and the protective layer remains on unnecessary portions of the transferred product. A malfunction that occurs.
In view of the above points, the thickness of the protective layer to which the silane coupling agent is added is preferably 0.5 to 5 μm.

A fifth characteristic configuration of the transfer sheet of the present invention is that the base sheet is a resin sheet, a metal foil, a cellulose-based sheet, or a composite of the respective sheets.

  When the base sheet is a resin sheet, a metal foil, a cellulosic sheet, or a composite of the above sheets as in this configuration, the adhesion between the first protective layer and the second protective layer by the addition of the silane coupling agent. In combination with the improvement, the peelability of the base sheet from the first protective layer is improved.

ここで、式中のＲは、エポキシ基、ビニル基、メタクリル基、メルカプト基、スチリル基のいずれかを少なくとも１以上含むアルキル直鎖であり、Ｄは、ＯＭｅ、ＯＥｔ、ＯＥｔＯＭｅ、ＯＥｔＯＥｔのいずれか１つであり、Ｍｅはメチル基、Ｅｔはエチル基を示す。 The characteristic means of the method for producing a transfer sheet of the present invention includes a step of forming a first protective layer mainly composed of acrylate on a base sheet, and a second step mainly comprising acrylate on the first protective layer. Forming a protective layer, and a protective layer that is at least one of the first protective layer and the second protective layer and is in an uncured state at the time of lamination, has a molecular weight of 100 to A silane coupling agent represented by the following formula of 500 is added to form a hard coat layer that protects the surface of the transferred product with both the first protective layer and the second protective layer .

Here, R in the formula is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. 1, Me represents a methyl group, and Et represents an ethyl group.

As in this configuration, a silane coupling agent having a molecular weight of 100 to 500 is added to the protective layer that is at least one of the first protective layer and the second protective layer and is in an uncured state when both are laminated. Then, in the protective layer to which the silane coupling agent is added, the silane coupling agent reacts with the resin material in the protective layer, and the reactant comes into contact with the resin constituting the other adjacent protective layer. . The adhesion between the first protective layer and the second protective layer is improved by the interaction between the reactant and the resin constituting the other protective layer adjacent thereto. As a result, it is possible to produce a transfer sheet that prevents delamination between the first protective layer and the second protective layer. In addition, the adhesion between the first protective layer and the second protective layer is improved, and the hardness of the entire hard coat layer is high.

It is a schematic cross section of the transfer sheet of the first embodiment. It is a schematic cross section of the transfer sheet of the second embodiment. It is a figure which shows the manufacturing process of the molded article using the transfer sheet of this invention. It is a figure which shows the manufacturing process of the molded article using the transfer sheet of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
[Transfer sheet]
FIG. 1 is a cross-sectional view showing the structure of a transfer sheet 1 according to this embodiment of the present invention. A transfer layer 3 in contact with one surface of the base sheet 2 is provided. The transfer layer 3 has a first hard coat layer 4, a second hard coat layer 5, and an adhesive layer 6 that are sequentially laminated from the base sheet 2 side. In the present embodiment, the first protective layer of the present invention is the first hard coat layer 4, and the second protective layer is the second hard coat layer 5.

  Of the layers constituting the transfer layer 3, each resin layer can be formed by a method similar to the conventional method unless otherwise specified. Examples of conventional layer forming methods include coating methods such as gravure coating, roll coating, and comma coating, printing methods such as gravure printing, and screen printing.

[Base sheet]
The base sheet 2 is composed of a sheet material or a film material conventionally used for supporting an image layer or a hard coat layer on the sheet. Film material refers to a sheet material made of synthetic resin. As the synthetic resin, polypropylene resin, polyethylene resin, polyamide resin, polyester resin, acrylic resin, polyvinyl chloride resin and the like can be used. In addition, a metal sheet such as aluminum foil or copper foil, a cellulose sheet such as glassine paper, coated paper, cellophane, or a composite of each of the above-mentioned sheets having releasability as a base sheet of a normal transfer sheet It can be used as a base sheet.

[Transfer layer]
The transfer layer 3 is a layer provided on one side of the base sheet 2 and transferred from the base sheet 2 to the surface of the transfer target. The transfer layer 3 includes a first hard coat layer (first protective layer) 4, a second hard coat layer (second protective layer) 5, and an adhesive layer 6 that are sequentially stacked from the base sheet 2 side.

  The first hard coat layer 4 and the second hard coat layer 5 are arranged on the surface of the transferred body when the substrate sheet 2 is peeled off from the transferred body after the transfer, and are above a certain level to protect the transferred body. Has a hardness of. Examples of the material of the hard coat layer include ionizing radiation curable resins such as cyanoacrylate and urethane acrylate, and thermosetting resins such as acrylic and urethane. The first hard coat layer 4 and the second hard coat layer 5 use the same resin material. When the resin material of the first hard coat layer 4 and the resin material of the second hard coat layer 5 are the same, the adhesion between them is improved.

ここで、式中のＲは、エポキシ基、ビニル基、メタクリル基、メルカプト基、スチリル基のいずれかを少なくとも１以上含むアルキル直鎖であり、Ｄは、ＯＭｅ、ＯＥｔ、ＯＥｔＯＭｅ、ＯＥｔＯＥｔのいずれか１つである。Ｍｅはメチル基、Ｅｔはエチル基を示す。 A silane coupling agent represented by the following chemical formula is added to the second hard coat layer 5.

Here, R in the formula is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. One. Me represents a methyl group, and Et represents an ethyl group.

  The polymer used for the protective layers (hard coat layers) 4 and 5 has a specific blending amount in consideration of physical and chemical performance requirements of the protective layer before and after irradiation with active energy rays. That is, the (meth) acryl equivalent is 100 to 300 g / eq, preferably 150 to 300 g / eq, from the viewpoint of curability when irradiated with active energy rays. When the (meth) acrylic equivalent is greater than 300 g / eq, the wear resistance after irradiation with active energy rays is insufficient, and it is difficult to obtain a product with a weight less than 100 g / eq. Moreover, the hydroxyl value of a polymer is 20-500, Preferably it is set to 100-300 from the reactive point with the polyfunctional isocyanate used together. When the hydroxyl value is less than 20, the reaction with the polyfunctional isocyanate is insufficient, and the degree of thermal crosslinking of the protective layers (hard coat layers) 4 and 5 of the transfer sheet 1 is low. Therefore, there is a disadvantage that it becomes difficult to print and roll up the transfer sheet 1 due to remaining adhesiveness or insufficient solvent resistance. Also, it is difficult to obtain those having a hydroxyl value exceeding 500. The weight average molecular weight of the polymer is 5000 to 50000, preferably 8000 to 40000. If the weight average molecular weight of the polymer is less than 5,000, the adhesiveness of the protective layers (hard coat layers) 4 and 5 of the transfer sheet 1 may remain or the solvent resistance may be insufficient. There are disadvantages such as it becomes difficult to remove and a clear picture cannot be obtained. On the other hand, if it exceeds 50000, the resin viscosity becomes too high and the ink application workability is lowered.

There is no limitation in particular as a manufacturing method of a polymer, A conventionally well-known method is employable. For example, [1] a method of introducing a (meth) acryloyl group into a part of a side chain of a polymer containing a hydroxyl group, [2] α, β-unsaturation containing a hydroxyl group in a copolymer containing a carboxyl group A method in which a monomer is subjected to a condensation reaction, [3] a method in which an α, β-unsaturated monomer containing an epoxy group is added to a copolymer containing a carboxyl group, and [4] an epoxy group-containing polymer. There is a method of reacting an α, β-unsaturated carboxylic acid.

Taking the method [4] as an example, the method for producing the polymer used in the present invention will be described more specifically. For example, the polymer used in the present invention can be easily obtained by a method in which an α, β-unsaturated carboxylic acid such as acrylic acid is reacted with a polymer having a glycidyl group. Preferred polymers having a glycidyl group include, for example, a homopolymer of glycidyl (meth) acrylate and a copolymer of glycidyl (meth) acrylate and an α, β-unsaturated monomer not containing a carboxyl group. Can be mentioned. Examples of the α, β-unsaturated monomer not containing a carboxyl group include various (meth) acrylic acid esters, styrene, vinyl acetate, acrylonitrile and the like. Use of an α, β-unsaturated monomer containing a carboxyl group is not preferred because crosslinking occurs during the copolymerization reaction with glycidyl (meth) acrylate, resulting in increased viscosity or gelation.

  In any case, when adopting each of the methods [1] to [4], the conditions such as the types of monomers and polymers used, the amount of these used, etc. are set so as to satisfy the numerical limit range related to the polymer. Must be performed as appropriate. Such operations are well known to those skilled in the art.

  In the present invention, the polyfunctional isocyanate used in combination with the polymer is not particularly limited, and various known ones can be used. For example, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, 1,6-hexane diisocyanate, the above trimer, a prepolymer obtained by reacting a polyhydric alcohol with the above diisocyanate, etc. Can be used. In the present invention, the reason why the polyfunctional isocyanate is used in combination with the polymer is that when the pattern layer or the adhesive layer 6 is laminated on the protective layers (hard coat layers) 4 and 5, the adhesiveness of the protective layer before irradiation with active energy rays is increased. It is to keep low and satisfy the resistance to the solvent contained in the ink for forming the pattern layer and the adhesive layer 6 to some extent. That is, a hydroxyl group contained in a polymer is reacted with an isocyanate group of a polyfunctional isocyanate to form a mild thermal cross-linked product, thereby imparting the above performance.

  The proportion of the polymer and polyfunctional isocyanate used is determined so that the ratio of the number of hydroxyl groups to the number of isocyanate groups in the polymer is 1 / 0.01 to 1/1, preferably 1 / 0.05 to 1 / 0.8. Is done.

  Moreover, the active energy ray-curable resin composition used for the protective layers (hard coat layers) 4 and 5 can contain the following components as needed in addition to the polymer and the polyfunctional isocyanate. That is, reactive diluent monomers, solvents, colorants, and the like. In addition, when an electron beam is used for irradiation with active energy rays, a sufficient effect can be exhibited without using a photopolymerization initiator. However, when ultraviolet rays are used, various known photopolymerization initiators are added. There is a need to. The protective layers (hard coat layers) 4 and 5 may be colored or uncolored.

  The active energy ray-curable resin composition used for the protective layers (hard coat layers) 4 and 5 may contain a lubricant as necessary. This is because the surfaces of the protective layers (hard coat layers) 4 and 5 are roughened, so that the protective layers (hard coat layers) 4 and 5 are easily wound as a sheet and blocking is difficult to occur. In addition, resistance to rubbing and scratching can be increased. As the lubricant, for example, waxes such as polyethylene wax, paraffin wax, synthetic wax and montan wax, and synthetic resins such as silicone and fluorine can be used. The lubricant is contained in an amount of 0.5 to 15% by weight, preferably 1 to 6% by weight. When the amount of the lubricant is less than 0.5% by weight, the effects of blocking prevention and friction scratch resistance are reduced, and when it exceeds 15% by weight, the transparency of the protective layers (hard coat layers) 4 and 5 is extremely deteriorated.

  The active energy ray-curable resin composition used for the protective layers (hard coat layers) 4 and 5 contains an ethylenically unsaturated group, a hydroxyl group, and an isocyanate group. When this active energy ray-curable resin composition is heated, the hydroxyl group and the isocyanate group react to crosslink the resin. Moreover, when this active energy ray-curable resin composition is exposed to active energy rays, ethylenically unsaturated groups are polymerized and the resin is crosslinked. That is, the active energy ray-curable resin composition used for the protective layers (hard coat layers) 4 and 5 is crosslinked by both heat and active energy rays.

  If necessary, the adhesive layer 6 is provided on the surface of the transfer layer 3 that is closest to the transfer target. The adhesive layer 6 adheres the transfer layer 3 and the transfer object during transfer. As the adhesive layer 6, a heat-sensitive or pressure-sensitive resin suitable for the transfer target is appropriately used. For example, when the material of the transfer object is an acrylic resin, an acrylic resin may be used.

  In addition, when the material of the transferred material is polyphenylene oxide / polystyrene resin, polycarbonate resin, styrene copolymer resin, or polystyrene blend resin, acrylic resin, polystyrene resin, polyamide having an affinity for these resins A series resin or the like may be used. Furthermore, when the material of the decoration object is polypropylene resin, chlorinated polyolefin resin, chlorinated ethylene-vinyl acetate copolymer resin, cyclized rubber, and coumarone indene resin can be used.

  A release layer may be further formed between the base sheet 2 and the transfer layer 3. The release layer may be separated from the transfer layer 3 together with the base sheet 2 during transfer, or may be separated from the base sheet 2 to form the outermost surface of the transfer layer 3. As the material of the release layer, melamine resin, silicone resin, fluorine resin, cellulose derivative, urea resin, polyolefin resin, paraffin resin, and composites thereof can be used.

[Transfer sheet manufacturing method]
The transfer sheet 1 of the present invention is produced in the same manner as a conventional transfer sheet except that a silane coupling agent is added to the second hard coat layer (second protective layer) 4 of the transfer layer 3.

  For example, the base sheet 2 is prepared, and the layers constituting the transfer layer 3 are sequentially formed on one side thereof. The layers constituting the transfer layer 3 are the first hard coat layer 4, the second hard coat layer 5, and the adhesive layer 6 as described above. If necessary, a release layer is formed on the surface of the base sheet 2 on the side where the transfer layer 3 contacts.

  A first hard coat layer 4 is formed as a transfer layer 3 on one side of the base sheet 2, an uncured second hard coat layer 5 is formed on the first hard coat layer 4, and an adhesive layer 6 is formed thereon. Thus, the transfer sheet 1 of the present invention in which the transfer layer 3 is formed on one side of the base sheet 2 is obtained.

[Transfer method to article]
Using the transfer sheet 1 of the present invention, an article can be decorated by hot roll transfer or in-mold molding. For example, in hot roll transfer, as shown in FIG. 3, the surface of the transfer sheet 1 on the adhesive layer 6 side (opposite side of the base sheet 2) is superimposed on the surface of the transfer target 10, and the roll transfer machine 11, up-down Heat and pressure are applied from the substrate sheet 2 side of the transfer sheet 1 using a transfer machine such as a transfer machine. By doing so, the transfer sheet 1 adheres to the surface of the transfer target 10. Next, when the base sheet 2 is peeled after cooling, the transfer layer 3 is transferred to the surface of the transfer target 10 and the surface of the article is coated (decorated).

  In in-mold molding, as shown in FIG. 4, first, the transfer sheet 1 is fed into the molding die in such a direction that the base sheet 2 is in contact with the inner surface of the die (fixed die 12). Next, the mold (fixed mold 12 and movable mold 13) is closed, and the molten resin 14 is in contact with the surface of the transfer sheet 1 on the adhesive layer 6 side (opposite side of the base sheet 2), that is, the transfer sheet 1 is melted. The molten resin 14 is filled in the mold so as to be sandwiched between the resin 14 and the inner surface of the mold (movable mold 13). As a result, the molten resin 14 is molded, and at the same time, the transfer sheet 1 is bonded to the surface of the resin molded product. The resin molded product is cooled, the mold is opened, and the resin molded product is taken out. When the base sheet 2 is finally peeled off, the transfer layer 3 is transferred onto the surface of the resin molded product, and the surface of the resin molded product is coated (decorated).

  The material of the transfer target 10 is not particularly limited as long as it has been conventionally transferred by the transfer sheet 1 or can devise the components of the adhesive layer 6 to adhere the transfer layer 3 to the surface. Various synthetic resins, members made of metal, glass, wood, paper, and these painted and decorative objects are used as the transfer target 10.

  A silane coupling agent may be added to at least one of the first protective layer 4 and the second protective layer 5 that is in an uncured state at the time of lamination. When a silane coupling agent having a molecular weight of 100 to 500 is added to the protective layer in an uncured state at the time of laminating both of the first protective layer 4 and the second protective layer 5, In the protective layer to which the silane coupling agent is added, the silane coupling agent reacts with the resin material in the protective layer. The reactant comes into contact with the resin constituting the adjacent protective layer, and the adhesion between the first protective layer 4 and the second protective layer 5 is improved by the interaction between the reactant and the resin. As a result, delamination between the first protective layer 4 and the second protective layer 5 in the transfer sheet 1 can be prevented.

Moreover, the hardness of the said protective layer improves because the cohesion force of the protective layer to which the silane coupling agent was added improves. As a result, the overall hardness of the protective layers 4 and 5 is improved.
Further, by improving the adhesion between the first protective layer 4 and the second protective layer 5, the protective layer to which the silane coupling agent is added is adjacent to the other protective layer, so that three or more protective layers can be formed. Even if formed, delamination can be suppressed. When three or more protective layers are formed in this way, the hardness of the entire protective layer becomes very high.

  When the first protective layer 4 and the second protective layer 5 are both hard coat layers protecting the surface of the transfer target 10, the adhesion between the hard coat layers is improved and the hardness of the entire hard coat layer is high. It will be a thing.

  The addition amount of the silane coupling agent is preferably 0.5 to 5.0 w% of the resin component in the protective layer according to the addition. When the addition amount of the silane coupling agent is less than 0.5 w% of the resin component in the protective layer according to the addition, the adhesion between the first protective layer 4 and the second protective layer 5 is hardly improved. On the other hand, when the addition amount of the silane coupling agent exceeds 5.0 w%, the protective layer according to the addition is gelled, so that the first protective layer 4 and the second protective layer 5 can be appropriately laminated. become unable.

  The thickness of the protective layer to which the silane coupling agent is added is preferably 0.5 to 5 μm. When the thickness of the protective layer to which the silane coupling agent is added is less than 0.5 μm, the wear resistance and chemical resistance of the protective layers 4 and 5 are weakened. On the other hand, if the thickness of the protective layer to which the silane coupling agent is added exceeds 5 μm, the cost is increased, and the foil of the transfer sheet 1 is deteriorated. There is a problem that 4 and 5 remain.

  When the base sheet 2 is a resin sheet, a metal foil, a cellulosic sheet, or a composite of each of the above sheets, the first hard coat layer (first protective layer) 4 and the second protective layer are added by adding a silane coupling agent. Combined with the improvement of the adhesion with the (second hard coat layer) 5, the peelability of the base sheet 2 from the first protective layer 4 is improved.

[Second Embodiment]
In the present embodiment, as in the first embodiment, the transfer layer 3 includes a first hard coat layer (first protective layer) 4 and a second hard coat layer (second protective layer) that are laminated in order from the base sheet 2 side. Layer) 5 and an adhesive layer 6.

  However, unlike the first embodiment, the first hard coat layer (first protective layer) 4 is composed of the following polymer, and no silane coupling agent is added. As a polymer used for the first hard coat layer (first protective layer) 4, polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, To those obtained by appropriately mixing unsaturated ethylene oligomers and unsaturated ethylene monomers such as melamine (meth) acrylate, triazine acrylate, epoxy-modified (meth) acrylate, urethane-modified (meth) acrylate, and (meth) acryl-modified polyester The composition etc. which added the polymerization initiator and the sensitizer are mentioned.

  In addition, a compound having a reactive double bond, having a (meth) acryloyl group, for example, methyl (meth) acrylate, ethyl (meth) acrylate, benzyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, phenoxy Monofunctional types such as diethylene glycol (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethyl It is a multifunctional type such as propane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. May be.

  Moreover, oligomers, such as polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligo acrylate, alkyd acrylate, polyol acrylate, etc. may be sufficient. Furthermore, for example, a styrene monomer, α-methylstyrene, divinylbenzene, vinyl acetate, pentene, hexene, an unsaturated compound or the like having a vinyl group or an allyl group may be used. These compounds are further introduced with polar groups such as hydroxyl groups, amino groups, carboxyl groups, carbonyl groups, and epoxy groups in order to improve adhesion to the printing surface (described later) and compatibility with the base protection material. There are things to do.

  In addition, about the 2nd hard-coat layer (2nd protective layer) 5 to which a silane coupling agent is added, the polymer similar to 1st Embodiment is used.

[Third Embodiment]
In the present embodiment, a pattern layer 8 is added to the transfer layer 3. As shown in FIG. 2, if the first protective layer in the transfer sheet 1 is the hard coat layer 7 and the second protective layer is the pattern layer 8, the pattern layer 8 is sufficiently protected by the hard coat layer 7.

  As a material of the pattern layer 8, a resin such as a polyvinyl resin, a polyamide resin, a polyacrylic resin, a polyurethane resin, a polyvinyl acetal resin, a polyester urethane resin, a cellulose ester resin, or an alkyd resin is used as a binder. Colored inks containing various color pigments or dyes as colorants may be used. In the case of forming a metal color, a pearl pigment in which titanium oxide is coated on metal particles such as aluminum, titanium, bronze, or mica can be used.

  As a method for forming the picture layer 8, a normal printing method such as an offset printing method, a gravure printing method, or a screen printing method may be used. In particular, the offset printing method and the gravure printing method are suitable for performing multicolor printing and gradation expression. In the case of a single color, a coating method such as a gravure coating method, a roll coating method, or a comma coating method may be employed.

  When the transfer sheet 1 in which the hard coat layer 7 and the picture layer 8 are laminated is exposed to an environment where moisture or alcohol is used, water, alcohol, or the like enters between the hard coat layer 7 and the picture layer 8. Then, the design layer 8 may swell and the shape of the design constituting the design layer 8 may be impaired.

  However, when the hard coat layer 7 to which the silane coupling agent is added is formed on the base sheet 2 as in this configuration, a part of the silane coupling agent is on the surface side of the hard coat layer 7 (with the base sheet 2 and Moves to the opposite side), and the surface tension of the hard coat layer 7 is reduced. Then, the pattern layer 8 is formed on the hard coat layer 7 so as to face the silane coupling agent. At this time, since the silane coupling agent is distributed on the surface of the hard coat layer 7 like a surfactant, the effect of the silane coupling agent is increased, and the adhesion between the hard coat layer 7 and the pattern layer 8 is improved. . Thereby, the pattern layer 8 is reliably protected by the hard coat layer 7.

The present invention will be specifically described by the following examples, but the present invention is not limited thereto. In the examples, the amount represented by “part” or “%” is based on weight unless otherwise specified.
Examples and comparative examples were evaluated based on the following evaluation criteria.

(1) Pencil hardness As a hardness evaluation of the hard coat layer, the pencil hardness of the hard coat layer arranged on the surface of the decorative molded product was measured by a method based on JIS K 5400.

(2) Adhesiveness (cross cut)
The adhesion between the first protective layer (first hard coat layer, hard coat layer) and the second protective layer (second hard coat layer, pattern layer) in the decorative molded product was measured. The measuring method of adhesiveness was performed based on the cross-cut method described in JIS K5600-5-6.
In addition, the adhesive evaluation of a 1st protective layer and a 2nd protective layer evaluated by either of the following.
○: The edges of the cuts are completely smooth, and there is no peeling in any lattice eye.
(Triangle | delta): The small peeling could be confirmed to the coating film in the intersection of cut, and the peeling had generate | occur | produced between the 1st protective layer and the 2nd protective layer. Peeling is less than 5% of the cross-cut portion.
X: Small peeling can be confirmed in the coating film at the intersection of the cuts, and the peeling occurred between the hard coat layer and the hard coat auxiliary layer. Peeling is 5% or more of the cross-cut portion.

(3) Cracking property The transfer sheet was placed in a mold and subjected to in-mold injection molding of a polycarbonate / ABS alloy resin, and then the base sheet was removed to obtain a molded product of KEYDECK, which is a component of a personal computer. The area of the surface on which the hard coat layer of the obtained KEYDECK molded product exists is 120 cm ² . And the surface of the hard-coat layer of a molded article was observed visually, the presence or absence of the crack was confirmed, and it evaluated by either of the following.
○: No crack was confirmed.
Δ: 1 to 3 cracks were confirmed in a 50 cm ² molded product.
X: Cracks at 4 or more locations were confirmed in a 50 cm ² molded product.

(4) Blocking resistance It measured about the blocking resistance of the hard-coat layer in a transfer sheet. The measuring method of adhesiveness was performed based on the blocking resistance described in 6.2.2 of JIS K5701-1. In addition, the blocking resistance evaluation of the hard coat layer was evaluated by any of the following.
○: When the transfer sheets are peeled off one by one from a plurality of superimposed transfer sheets, each transfer sheet is peeled between the base sheet and the adhesive layer, and the first protective layer (first hard coat layer or hard No peeling between the coating layer) and the second protective layer (second hard coat or pattern layer).
X: When the transfer sheets are peeled off one by one from a plurality of the superimposed transfer sheets, each transfer sheet or a part of the transfer sheets is not peeled between the base sheet and the adhesive layer, and the first protective layer ( Peeling occurs between the first hard coat layer or hard coat layer) and the second protective layer (second hard coat layer or pattern layer).

(5) Alcohol resistance The decorated molded article was immersed in a methanol solution for 10 minutes and then naturally dried for 60 minutes. Next, the decorative molded product that had been naturally dried was tested in accordance with the cross-cut method described in JIS K5600-5-6. In addition, the alcohol resistance of the pattern layer and the hard coat layer was evaluated by either of the following in response to the above results.
○: The edges of the cut are completely smooth, and there is no peeling in the eyes of any lattice.
(Triangle | delta): The small peeling was confirmed to the coating film in the intersection of cut, and the peeling had generate | occur | produced between the hard-coat layer and the pattern layer. Peeling was less than 30% of the cross-cut portion.
X: Small peeling was confirmed in the coating film at the intersection of the cuts, and the peeling occurred between the hard coat layer and the pattern layer. Peeling was 30% or more of the cross-cut portion.

(6) Wear resistance In accordance with JIS K7204, using a Taber friction tester (wear wheel: CS-10, load: 1 Kg / arm, rotation speed: 500 rotations) manufactured by Yasuda Seiki Seisakusho Co., Ltd. The hard coat layer disposed on the surface of the molded product was rubbed. Then, the number of rotations of the wear wheel until the hard coat layer was worn and penetrated was measured. In addition, the abrasion resistance of the hard coat layer was evaluated by any of the following.
○: It took 1000 or more revolutions to penetrate.
Δ: It took 500 to 1000 revolutions to penetrate.
X: The number of rotations of less than 500 was required to penetrate.
[Example of Embodiment 1]

[Example 1]
A polyester resin film having a thickness of 38 μm was used as a base sheet, and a release layer was formed on the base sheet by applying a melamine resin release agent to a thickness of 1 μm by a gravure printing method. A part 200 (solid content 100 parts), 1,6-hexane diisocyanate trimer (trade name Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) and photopolymerization initiator (trade name Irgacure 184, manufactured by Ciba Geigy) 5 The 1st hard-coat layer (1st protective layer) which mix | blended the part was formed by the gravure printing method. The thickness of the first hard coat layer (first protective layer) was 4 μm. The first hard coat layer was half-crosslinked and cured by heating at 150 ° C. for 20 seconds. On the first hard coat layer, 200 parts of the following varnish A (solid content 100 parts), 1,6-hexane diisocyanate trimer ( Product name Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd. 5 parts, photopolymerization initiator (trade name Irgacure 184, manufactured by Ciba Geigy) and vinyltrimethoxysilane (silane coupling agent, product name KBM-1003, Shin-Etsu Chemical) The 2nd hard-coat layer (2nd protective layer) which mix | blended 1 part of Kogyo Co., Ltd. was formed with the gravure printing method. The thickness of the second hard coat layer was 0.7 μm. Furthermore, the second hard coat layer was half-crosslinked and cured by heating at 150 ° C. for 20 seconds, and an acrylic resin was printed and formed as an adhesive layer on the second hard coat layer by a gravure printing method to obtain a transfer sheet. .

Varnish A was obtained as follows. First, 175 parts of glycidyl methacrylate (hereinafter referred to as GMA), 75 parts of methyl methacrylate (hereinafter referred to as MMA), 1.3 parts of lauryl mercaptan are added to a reactor equipped with a stirrer, a cooling pipe, a dropping funnel and a nitrogen introduction pipe. , 1000 parts of butyl acetate and 2,2′-azobisisobutyronitrile (hereinafter,
After charging 7.5 parts (referred to as AIBN), the temperature in the system was increased to about 90 ° C. over about 1 hour under a nitrogen stream, and the temperature was kept for 1 hour. Next, the mixture was dropped into the system in about 2 hours under a nitrogen stream from a dropping funnel previously charged with a mixture consisting of 525 parts of GMA, 225 parts of MMA, 3.7 parts of lauryl mercaptan and 22.5 parts of AIBN. After keeping the same temperature for 3 hours, 10 parts of AIBN was charged and kept warm for 1 hour. Then, it heated up at 120 degreeC and heat-retained for 2 hours. After cooling to 60 ° C, the nitrogen inlet tube was replaced with an air inlet tube, 355 parts of acrylic acid (hereinafter referred to as AA), 2.0 parts of methoquinone and 5.4 parts of triphenylphosphine were charged and mixed, and then under air bubbling The temperature was raised to 110 ° C. After incubating at the same temperature for 8 hours, 1.4 parts of methoquinone was added and cooled, and ethyl acetate was added so that the non-volatile content was 50% to obtain varnish A. The polymer contained in varnish A had an acrylic equivalent of 270 g / eq, a hydroxyl value of 204, and a weight average molecular weight of 18000 (based on styrene conversion by GPC).

  The transfer sheet was transferred to the surface of the molded product using a simultaneous molding transfer method, and then the base sheet was peeled off, and the first hard coat layer and the second hard coat layer were completely crosslinked and cured by irradiation with ultraviolet rays. The molding conditions were a resin temperature of 240 ° C., a mold temperature of 55 ° C., and a resin pressure of about 300 kg / cm 2. The molded product was made of acrylic resin, and was formed into a tray shape of 95 mm in length, 65 mm in width, rise of 4.5 mm, and R2.5 mm at the corner. Irradiation conditions were 120 w / cm, 6 lamps, a lamp height of 10 cm, and a belt speed of 15 m / min. Various evaluations were performed on the transfer sheet and the transferred molded product (decorated molded product). The evaluation results are shown in Table 1.

[Examples 2 to 9 and Comparative Examples 1 to 9]
Except that the resin of the first hard coat layer, the resin of the second hard coat layer, the type and addition amount of the silane coupling agent, and the thicknesses of the first hard coat layer and the second hard coat layer were changed as shown in Table 1. Produced a transfer sheet in the same manner as in Example 1, obtained a transferred molded product (decorated molded product), and variously evaluated it. The evaluation results are shown in Table 1.

The following is clear from the evaluation results in Table 1. In Examples 1 to 9 in which a silane coupling agent was added to the second hard coat layer (second protective layer) in a polymer ratio of 0.5 to 5.0 w%, the pencil hardness was H or more, and both adhesion and cracking It is generally good and has excellent blocking resistance.
On the other hand, in Comparative Examples 1 and 6 in which no silane coupling agent was added to the second hard coat layer, satisfactory results were obtained in adhesion, cracking, and blocking resistance regardless of the thickness of the second hard coat layer. It is not done.
In Comparative Example 2 in which the molecular weight of the silane coupling agent exceeds 500, satisfactory results in adhesion and blocking resistance are not obtained, and in Comparative Example 3 in which the molecular weight of the silane coupling agent is less than 100, the second hard coat layer The painting process itself could not be performed.
In Comparative Examples 4 and 5 in which the same silane coupling agent as in Examples 1 to 4 was added to the second hard coat layer, Comparative Example 4 in which the amount of the silane coupling agent was too small was satisfactory in adhesion and blocking resistance. No results were obtained, and in Comparative Example 5 in which the amount of the silane coupling agent was excessive, the coating process itself of the second hard coat layer could not be performed.
Moreover, in the comparative examples 7-9 which added the silane coupling agent which uses aminosilane, ureidosilane, and isocyanatesilane as a functional group, the coating process of the 2nd hard-coat layer was not able to be performed.
[Example of Embodiment 2]

[Example 1]
A polyester resin film with a thickness of 38 μm was used as a base sheet, and a release layer was formed on the base sheet by applying a melamine resin release agent to a thickness of 1 μm by a gravure printing method. A part 200 (solid content 100 parts), 1,6-hexane diisocyanate trimer (trade name Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) and photopolymerization initiator (trade name Irgacure 184, manufactured by Ciba Geigy) 5 A hard coat layer (first protective layer) in which parts were blended was formed by a gravure printing method. The thickness of the hard coat layer was 0.5 μm. The hard coat layer is half-crosslinked and cured by heating at 150 ° C. for 20 seconds. Polycarbonate (PC) / ABS ink as the pattern layer and acrylic resin as the adhesive layer are sequentially printed on the hard coat layer by gravure printing. A transfer sheet was obtained.

  The transfer sheet was transferred to the surface of the molded product using a simultaneous molding transfer method, and then the base sheet was peeled off and irradiated with ultraviolet rays to completely crosslink and cure the protective layer. The molding conditions were a resin temperature of 240 ° C., a mold temperature of 55 ° C., and a resin pressure of about 300 kg / cm 2. The molded product was made of acrylic resin, and was formed into a tray shape of 95 mm in length, 65 mm in width, rise of 4.5 mm, and R2.5 mm at the corner. Irradiation conditions were 120 w / cm, 6 lamps, a lamp height of 10 cm, and a belt speed of 15 m / min. Various evaluations were performed on the transfer sheet and the transferred molded product (decorated molded product). The evaluation results are shown in Table 2.

[Examples 2 to 10 and Comparative Examples 1 to 9]
A transfer sheet was prepared in the same manner as in Example 1 except that the hard coat layer resin, the type and addition amount of the silane coupling agent, and the pattern layer resin were changed as shown in Table 2. (Decorated molded product) was obtained and subjected to various evaluations. The evaluation results are shown in Table 2.

The following is clear from the evaluation results in Table 2. In Examples 1 to 10 in which the silane coupling agent was added to the hard coat layer (first protective layer) in a polymer ratio of 0.5 to 5.0 w%, the pencil hardness was 2B or more, and the alcohol resistance and wear resistance were The adhesion is generally good and the blocking resistance is excellent.
On the other hand, in Comparative Example 1 in which no silane coupling agent was added to the hard coat layer, satisfactory results in alcohol resistance and adhesion were not obtained.
In Comparative Example 2 in which the molecular weight of the silane coupling agent exceeds 500, satisfactory results in adhesion and blocking resistance cannot be obtained. In Comparative Example 3 in which the molecular weight of the silane coupling agent is less than 100, the coating process of the hard coat layer Could not do itself.
In Comparative Examples 4 to 6 in which the same silane coupling agent as in Examples 1 to 4 was added to the hard coat layer, Comparative Example 4 in which the amount of the silane coupling agent was too small showed satisfactory results in adhesion and blocking resistance. In Comparative Example 5 in which the amount of the silane coupling agent was excessive, the hard coat layer coating process itself could not be performed. In Comparative Example 6, even when the amount of the silane coupling agent was substantially the same as in Examples 2 and 4, when the pattern layer was an ABS resin alone, satisfactory results were not obtained in terms of wear resistance and adhesion.
Further, in Comparative Examples 7 to 9 to which a silane coupling agent having a functional group of aminosilane, ureidosilane, or isocyanatesilane was added, the hard coat layer coating process could not be performed.

  The present invention forms a decorative layer on the surface of a metal body in a metal product used in various fields, such as automobiles, household appliances, mobile phones, personal computers, regardless of interior and exterior products. When widely available.

DESCRIPTION OF SYMBOLS 1 Transfer sheet 2 Base sheet 3 Transfer layer 4 1st hard-coat layer (1st protective layer)
5 Second hard coat layer (second protective layer)
6 Adhesive layer 7 Hard coat layer (first protective layer)
8 picture layer (second protective layer)
10 Transferee

Claims (6)

A base sheet;
A first protective layer formed on the base sheet;
A second protective layer formed on the first protective layer,
The first protective layer and the second protective layer are both hard coat layers that protect the surface of the transferred product,
Both of the hard coat layers constituting the first protective layer and the second protective layer are mainly composed of acrylate,
A transfer sheet obtained by adding a silane coupling agent represented by the following formula having a molecular weight of 100 to 500 and adhering both layers to at least one of the first protective layer and the second protective layer.

(In the formula, R is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. Me represents a methyl group, and Et represents an ethyl group.) The transfer sheet according to claim 1, wherein both of the hard coat layers constituting the first protective layer and the second protective layer are mainly composed of a varnish containing glycidyl methacrylate and methyl methacrylate. The transfer sheet according to claim 1 or 2 , wherein the addition amount of the silane coupling agent is 0.5 to 5.0 w% of the resin component in the protective layer according to the addition. The transfer sheet according to any one of claims 1 to 3 , wherein a thickness of the protective layer to which the silane coupling agent is added is 0.5 to 5 µm. It said base sheet is a resin sheet, metal foil, cellulosic sheet or the sheet as claimed in any one of claims 1 to 4 which is a composite of each sheet. Forming a first protective layer mainly composed of acrylate on a base sheet;
Forming a second protective layer mainly composed of acrylate on the first protective layer,
A silane coupling represented by the following formula having a molecular weight of 100 to 500 is applied to a protective layer that is at least one of the first protective layer and the second protective layer and is in an uncured state when both are laminated. Add the agent ,
A method for producing a transfer sheet, wherein a hard coat layer is formed to protect the surface of an object to be transferred with both the first protective layer and the second protective layer .

(In the formula, R is an alkyl straight chain containing at least one of an epoxy group, a vinyl group, a methacryl group, a mercapto group, and a styryl group, and D is any one of OMe, OEt, OEtOMe, and OEtOEt. Me represents a methyl group, and Et represents an ethyl group.)

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