JP3119463B2 - Laminated resin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marking film intended to be attached to a signboard, an automobile part, or the like.

[0002]

2. Description of the Related Art Conventionally, a marking film having a metal-like appearance in which a metal layer such as aluminum is laminated is generally used. However, when these marking films are attached to a metal plate or a glass plate, there is no particular problem in a short time, but when they are attached to a synthetic resin molded product such as urethane, polycarbonate, acrylic, polyester, etc. There was a problem that blisters were generated between them and the appearance was remarkably impaired.

Further, if the film is made hard to make blisters inconspicuous, followability to a curved surface is inferior, and apposition suitability is impaired. On the other hand, a method of preventing blistering by reducing the thickness of the metal layer is also conceivable.However, if the metal layer is thinned to such an extent that blistering does not occur,
The metal-like appearance of the film was significantly impaired, and the weather resistance was reduced.

Accordingly, an object of the present invention is to provide a laminated resin film having a metal-like appearance which does not cause blistering even when adhered to a synthetic resin molded product and has excellent curved surface followability, weather resistance and design.

[0005]

The present inventors have conducted various studies on the structure of a laminated resin film having a metal-like appearance in which metal layers are laminated, and have achieved the above object by providing fine voids in the metal layer. I learned that I can do it.

The present invention has been made on the basis of the above findings, and has a base film layer made of a synthetic resin having a total light transmittance of at least 50%, and a metal layer having fine voids laminated on one surface of the film. And a laminated resin film having a metal-like appearance, comprising a pressure-sensitive adhesive laminated on a surface of the metal layer that is not in contact with the base film layer.

Hereinafter, the laminated resin film having a metal-like appearance of the present invention will be described in detail. The base film layer used in the laminated resin film of the present invention is a layer made of a synthetic resin having a total light transmittance of at least 50%, and the thickness of the layer is not particularly limited, but is usually 10 μm to 200 μm, preferably 20 μm to 100 μm. If the thickness is smaller than the lower limit, durability and workability are inferior. If the thickness is larger than the lower limit, a step after sticking is conspicuous, which is not preferable in design. The total light transmittance of the base film layer is at least 50%, preferably 70% or more. If the total light transmittance is smaller than the lower limit, the metallic appearance is unfavorably deteriorated.

The synthetic resin constituting the base film layer is not particularly limited, and may be polyvinyl chloride, polyurethane, (meth) acrylic, acrylic urethane, acrylic urethane, acrylic melamine, vinyl fluoride, Synthetic resins such as vinylidene fluoride-based, ethylene-tetrafluoroethylene-based, and polyester-based resins can be used. Among them, polyvinyl chloride-based and polyurethane-based resins are preferable in processing and handling.

The tensile strength of the base film at 5% elongation is preferably 2 kg / cm or less. If the tensile strength at 5% elongation exceeds 2 kg / cm, it is not preferable because the ability to follow a curved surface is poor and the suitability for sticking is impaired.

A metal layer is laminated on one surface of the base film layer. The metal layer may be laminated directly on the base film layer or indirectly via a primer layer. The use of the above primer layer can improve the weather resistance and interlayer adhesion of the product of the present invention.

The resin constituting the primer layer is preferably a polyurethane-based or acrylic-based resin, and its thickness is not particularly limited, but is usually 1 μm to 20 μm. As a method of forming the base film layer and the primer layer,
Although not particularly limited, in order to maximize the metal-like appearance of the product of the present invention, it is preferable to adopt a forming method that has as high transparency as possible and reduces thickness unevenness.

That is, as a method for forming the base film layer, a solution casting method, a sol casting method, a calendering method, a T-die method, an inflation method and the like can be considered. Among them, the solution casting method and the sol casting method are preferable.

[0013] Further, many methods can be considered as a method for forming the primer layer. Among them, a solution casting method using a coater such as a gravure roll, a comma roll, a reverse roll or the like on a base film, or a releasable process paper or A method is preferred in which a primer layer is formed in advance on a polyester film or the like by the above-described coater or the like, and a base film layer is formed thereon by casting by a solution casting method or a sol casting method.

The base film layer and / or the primer layer have a total light transmittance of 50% of both laminated films.
The dye or the pigment can be blended within a range not less than the above. Further, an ultraviolet absorber and / or a primer layer may be added to the base film layer and / or the primer layer to improve weather resistance.
Alternatively, a light stabilizer can be blended.

As the ultraviolet absorber, besides benzotriazole type, benzophenone type and cyanoacrylate type,
Ultrafine zinc oxide, titanium oxide, or the like is used, and a hindered amine-based light stabilizer is used as the light stabilizer.

In the laminated resin film of the present invention, the laminated metal layer has fine voids. The fine voids may be formed at the same time as the formation of the metal layer. It may be formed after forming.

The fine voids need to penetrate the metal layer, which can be confirmed by observation with transmitted light of an optical microscope. The shape of the fine void may be a hole or a crack, and the diameter of the smallest circle surrounding any fine void is defined as the maximum diameter of the fine void.

It is preferable that the number of voids having a maximum diameter of 1 to 10 μm is 100 to 1000 / mm ² , and a large number of these voids is liable to impair the metal-like appearance of the product of the present invention. If the number is small, the blister resistance tends to be insufficient, which is not preferable. In addition, the presence of voids having a maximum diameter of 10 μm or more is not preferred because the appearance tends to be impaired. A void having a maximum diameter of 1 μm or less may or may not be present.

The thickness of the metal layer is preferably from 300 to 3000 A, and more preferably from 400 to 2000 A. When the thickness of the metal layer is thinner than the lower limit, the metal-like appearance is impaired, and the weather resistance tends to decrease.On the contrary, when the thickness is larger than the upper limit, the performance is not particularly improved, and the cost increases. Not preferred.

The metal constituting the metal layer is not particularly limited, but may be any metal having a so-called metal-like appearance, and may be a single metal or an alloy. Generally, aluminum, gold, silver, chromium, platinum and the like are preferably used, but aluminum is particularly preferably used from the viewpoint of cost and physical properties.

The method of forming the metal layer is not particularly limited, but a vacuum evaporation method and a sputtering method are preferably used in terms of productivity. As a method for laminating the metal layer and the base film layer, the metal layer may be laminated on the base film layer directly or via a primer layer, but may be subjected to a peeling treatment in advance. Alternatively, the metal layer may be formed on a base film such as a polyester film, and the base film layer may be formed on the metal layer directly or after forming a primer layer thereon.

As a method for forming the fine voids in the metal layer, for example, the maximum diameter is previously set on the surface on which the metal layer is to be laminated.
When 100 to 1000 protrusions / dents / mm ^{2 are} formed in advance, and a metal layer is formed thereon by a vacuum evaporation method, defects are generated on the side surfaces of the protrusions or depressions, and fine voids can be formed. The protrusions are formed, for example, by dispersing spherical fine particles in a primer resin solution and forming a primer layer to a thickness of about 1/2 or less of the diameter of the fine particles. The dents are formed by, for example, forming a base film layer on a peelable substrate film having fine projections by a solution casting method or a sol casting method. Alternatively, for example, it is formed by passing a base film layer formed in advance on a roller having fine projections so as to be in contact therewith.

Further, as another method for forming the fine voids,
For example, it is performed by forming a metal layer having no fine voids on one surface of the base film layer in advance and then performing a chemical or physical treatment on the metal layer. The chemical treatment is an etching method using an acid or an alkali, and the physical treatment is a sand blasting method, or a pair of nip pressures composed of a roller having a fine uneven surface and a roller having a smooth surface coated with particles such as diamond. There is a method of passing the film through a roller such that the metal layer is in contact with a roller having an uneven surface. As described above, examples of the method for forming the fine voids have been described, but the present invention is not limited to these examples, and any forming method may be used.

The pressure-sensitive adhesive layer is not particularly limited, and acrylic-, rubber-, and silicone-based pressure-sensitive adhesives can be used. However, acrylic-based pressure-sensitive adhesives are preferred in view of durability, reliability, blister resistance and the like. It can be used most preferably. The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably between 10 and 100 μm. If the thickness is too thin, the adhesive strength is unfavorably reduced, and if it is too thick, the adhesive strength is not particularly increased and the cost is disadvantageous. In addition, another primer layer can be provided between the metal layer and the primer layer in order to improve the adhesion reliability between the metal layer and the pressure-sensitive adhesive layer and / or to prevent corrosion of the metal layer.

The acrylic pressure-sensitive adhesive is preferably a pressure-sensitive adhesive layer formed of a solvent-type pressure-sensitive adhesive containing an unsaturated carboxylic acid ester-based copolymer as a main component. To 70 parts by weight, 0.1 to 15 parts by weight of a vinyl monomer having a crosslinkable functional group and a monomer of a different type copolymerizable with such a monomer
The glass transition temperature derived from 0 to 29.9 parts by weight is -20.
A pressure-sensitive adhesive layer formed by mixing 0.01 to 20 parts by weight of a crosslinking agent capable of crosslinking with the above-mentioned crosslinkable functional group with respect to 100 parts by weight of a copolymer at a temperature of not more than 0 ° C is preferable.

The unsaturated carboxylic acid ester monomer for obtaining the copolymer constituting the pressure-sensitive adhesive layer includes:
Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate (Meth) acrylate monomers and the like.

Examples of the vinyl monomer having a crosslinkable functional group for obtaining the above copolymer include vinyl monomers having a carboxyl group such as acrylic acid, methacrylic acid and itaconic acid, and hydroxymethyl esters of (meth) acrylic acid, Examples include vinyl monomers having a hydroxyl group such as ethyl ester, hydroxypropyl ester, hydroxybutyl ester, hydroxypentyl ester, hydroxyhexyl ester, hydroxyheptyl ester and hydroxyoctyl ester, and further include vinyl monomers having an epoxy group and an amino group. Can be Examples of monomers that can be copolymerized with the above-mentioned monomers and differ in type include vinyl ester monomers such as vinyl acetate and vinyl propionate.

The crosslinking agent is preferably a metal crosslinking agent or an organic polyisocyanate compound. Examples of the metal crosslinking agent include aluminum trisacetyl acetate, aluminum isopropylate, aluminum secondary butyrate, and titanium tetraisopropylate. , Titanium tetra normal butyrate, titanium tetra-2
-Ethylhexylate, antimony butyrate, zirconium secondary butyrate, zirconium diethoxy tertiary butyrate, hafnium tertiary butyrate, ethyl acetoacetate aluminum diisopropylate, triethanolamine titanium diisopropylate, and ammonium titanate Salt, tetraoctylene glycol titanate, polyalkyl titanate and the like. Further, as the organic polyvalent isocyanate compound, P-phenylene diisocyanate,
Aromatic polyisocyanates such as 4,4'-cyphenylmethane diisocyanate, 2,6-toluylene diisocyanate, xylylene diisocyanate, naphthalene 1,5-diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, 4,4 There are aliphatic polyisocyanates such as' -dicyclohexylmethane diisocyanate, and a derivative obtained by adding and condensing the above isocyanate monomer mainly for handling is preferably used.

Further, a protective layer (liner layer) subjected to a release treatment may be provided outside the pressure-sensitive adhesive layer. When it has a liner layer, it preferably has a peel resistance of about 2 to 50 g / cm, for example, it is preferable to use a liner layer of a silicone resin coat, and paper may be used as a support of the liner layer. Since smoothness affects the appearance of the product of the present invention after application, it is more preferable to use a plastic film having more excellent surface smoothness, for example, a polyester film. The thickness of the liner layer is not particularly limited, but is generally preferably 25 to 150 μm.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

【Example】

Example 1 A polyester-based carrier film having a thickness of 75 μm on one side, a total light transmittance of 92%, and a tensile strength at 5% elongation.
An acrylic resin-based coating agent (ST) was applied to the surface of a 1.5 kg / cm, 40 μm thick polyvinyl chloride transparent film (His Paint N-15F, manufactured by Nippon Carbide Industry Co., Ltd.
-540, manufactured by Nikka Polymer Co., Ltd.) by a comma direct method and dried at 140 ° C. for 8 minutes. The thickness of the coating layer after drying was 8 μ. Further, metal aluminum was deposited on the surface of the coating layer so as to have a thickness of 1500A.

Next, a roller having a surface coated with artificial crystal grains of diamond and having a fine uneven surface,
The above-mentioned vapor-deposited film was passed through a pair of pressure rollers composed of rollers having a smooth metal surface so that the vapor-deposited surface was in contact with the roller having the uneven surface.

When the surface of the vapor-deposited film was observed using a metallographic microscope, no crack was observed on the surface of the polyvinyl chloride-based transparent film from which the carrier film was peeled off, but the vapor-deposited surface had a length of 1 to 10 μm. About 1mm ² cracks
200 had occurred. Further, when observed with an optical microscope using transmitted light, it was confirmed that the crack penetrated the metal layer.

100 parts by weight of an acrylic pressure-sensitive adhesive solution (Nissetsu KP-1564, manufactured by Nippon Carbide Industry Co., Ltd.) and an isocyanate-based crosslinking agent (Nissetsu CK-101, Nippon Carbide Industry) (stock)
Casting a mixture of 3 parts by weight and 20 parts by weight of toluene
It was dried at 4 ° C. for 4 minutes to form a pressure-sensitive adhesive layer having a thickness of 40 μm.

Embodiment 2 In the embodiment 1, when performing the deposition of metallic aluminum,
The thickness was adjusted to 500A. Furthermore, the weight average molecular weight is about 370,000 by the gravure coating method on the evaporation surface.
Apply a 15% toluene solution of EMA homopolymer to the thickness
A 1.5 μm primer layer II was formed. Next, in the same manner as in Example 1, the vapor-deposited film was passed through a pressure roller so that the surface of the primer layer II was in contact with a roller having an uneven surface. Observation of the deposited surface using a metallographic microscope revealed that about 200 cracks having a length of 1 to 10 μm were formed per 1 mm ² .

Example 3 A polyester-based carrier film having a thickness of 75 μm on one side has a total light transmittance of 92% and a tensile strength at the time of 5% extension of 1.5.
kg / cm 40μm thick transparent polyvinyl chloride film (His Paint N-15F, Nippon Carbide Industrial Co., Ltd.)
100 parts by weight of a polycarbonate-based polyurethane resin solution (Lesaloid LU-4008, manufactured by Dainichi Seika Co., Ltd.) and monodispersed spherical fine particles (Tospearl 145, made of silicone resin) having a particle size of about 4.5 μm. Toshiba Silicone Co., Ltd.)
0.13 parts by weight was dispersed and applied by a gravure coating method, and dried at 140 ° C. for 8 minutes. The thickness of the coating layer after drying is about 1 μm, further about 5 μm in diameter, about 3-4 μm in height
m spherical or hemispherical protrusions of, it was found by observation with an electron microscope and an optical microscope which is about 200 / mm ² on the surface of the coating layer.

Next, a thickness of 500 A is applied to the surface of the coating layer.
Aluminum was vacuum-deposited to form a metal layer. Observation with an optical microscope using transmitted light revealed that the metal layer had ring-shaped voids with a diameter of about 5 μm formed at about 200 / mm ² .

100 parts by weight of an acrylic pressure-sensitive adhesive solution (Nissetsu KP-1564, manufactured by Nippon Carbide Industry Co., Ltd.) and an aluminum chelate cross-linking agent (Nissetsu CK-401, Nippon Carbide) Industrial Co., Ltd.
Casting a mixture of 4 parts by weight and 20 parts by weight of toluene
After drying at 4 ° C. for 4 minutes, a pressure-sensitive adhesive layer having a thickness of 40 μm was formed and laminated on the vapor deposition surface of the vapor deposition film.

Example 4 A 75 μm thick polyester film subjected to a release treatment was
Polycarbonate polyurethane resin solution (Rezamine NE-883) blended with 3PHR of benzotriazole UV absorber (Tinuvin 213, manufactured by Ciba Geigy) and 2PHR of hindered amine light stabilizer (Sanol LS-622LD, manufactured by Sankyo)
6, manufactured by Dainichi Seika Co., Ltd.) at 90 ° C for 5 minutes followed by 14
By drying at 0 ° C. for 4 minutes, a base film layer having a thickness of 40 μm was formed. Further, vacuum evaporation of metallic aluminum was performed on the surface of the base film layer so as to have a thickness of 1000A. Thereafter, the same operation as in Example 1 was performed to obtain a laminated resin film of the present invention.

Comparative Example A laminated resin film was obtained by laminating the vapor-deposited film and the pressure-sensitive adhesive layer in Example 1 without passing the film through a sandwich roller.

[0040]

[Table 1]

Claims (6)

(57) [Claims] 1. A base film layer made of a synthetic resin the total light transmittance of at least 50%, a fine void maximum diameter laminated on one surface was 1~10μm of penetration of the film 100
Metal layer having ~ 1000 / mm2 and the base of the metal layer
It consists of an adhesive layer laminated on the surface not in contact with the film.
Laminated resin fill with metallic appearance
M 2. The method according to claim 1, wherein the base film layer comprising the synthetic resin layer is
The tensile strength at 5% elongation is 2 kg / cm or less.
3. The laminated resin film according to item 1. 3. The laminated resin film according to claim 1, wherein the synthetic resin is a polyvinyl chloride resin or a polyurethane resin. 4. The laminated resin film according to claim 1, wherein the thickness of the metal layer is in the range of 300 to 3000 A. 5. The method according to claim 1, wherein said metal layer is made of aluminum.
5. The laminated resin film according to any one of to 4 above. 6. The laminated resin according to claim 1, wherein the metal layer is laminated on the base film layer via a polyurethane or acrylic primer layer provided on one surface of the base film layer. the film.