WO2014119271A1

WO2014119271A1 - Transfer film for decoration

Info

Publication number: WO2014119271A1
Application number: PCT/JP2014/000377
Authority: WO
Inventors: 渡邉　学; 啓佑松田; 友美樋爪; 恵渡邊
Original assignee: 凸版印刷株式会社
Priority date: 2013-01-30
Filing date: 2014-01-27
Publication date: 2014-08-07
Also published as: JP5979026B2; KR20150110612A; CN104995028A; TW201441064A; CN104995028B; JP2014144625A

Abstract

Provided is a transfer film for decoration, which exhibits satisfactory molding performance during injection molding, while having excellent surface protection performance. A transfer film for decoration according to the present invention is obtained by sequentially laminating, on the surface of a supporting film, a mold release layer (2), a hard coat layer (3), a primer layer (4), a decorative layer (5) and a bonding layer (6). The hard coat layer (3) is formed of a tack-free ultraviolet curable composition which contains at least an acrylic acrylate resin that contains a hydroxyl group and has a weight average molecular weight of from 40,000 to 100,000 (inclusive), an ultraviolet initiator, silica particles having an average particle diameter of from 10 nm to 100 nm (inclusive), and a polytetrafluoroethylene powder having an average particle diameter of from 1 μm to 10 μm (inclusive). The primer layer (4) is formed of a two-package curable resin which contains at least an acrylic polyol resin, a polyisocyanate compound and a vinyl chloride-vinyl acetate copolymer resin containing a hydroxyl group.

Description

Decorative transfer film

The present invention relates to a decorative transfer film, and more particularly to a simultaneous molding decorative transfer film having molding transferability and excellent surface protection performance.

As a manufacturing method for obtaining a decorated molded product having a surface excellent in scratch resistance, chemical resistance, etc., a transfer film having a hard coat layer and a decorative layer is inserted into a mold during injection molding, A method of transferring a hard coat layer and a decorative layer to a molding resin (transfer object) simultaneously with molding by using hot pressure at the time of injection molding is used. In recent years, the hard coat layer of the transfer film (hereinafter, also referred to as “molded simultaneous decorating transfer film”) is mainly UV curable type rather than thermosetting type. More recently, the hard coat layer before transfer is in a semi-cured state capable of being cured by ultraviolet rays, and an after-curing type transfer film in which the hard coat layer is completely cured by irradiating with ultraviolet rays after molding and transfer has become mainstream.

This molding simultaneous decorating transfer film needs to correspond to various molding conditions (injection speed, resin temperature, holding pressure, cooling temperature, cooling time) and mold shape. For this reason, there are many problems that may occur in the simultaneously molded decorative transfer film. Examples of the main defects derived from the transfer film in the simultaneous decoration of molding include short (chip), burr, washout (pattern flow near the gate), whitening, ripples, cracks, and delamination.
On the other hand, examples of the items required as the surface protection performance of the molded simultaneous decorative transfer film include adhesion to the molding resin, pencil hardness, abrasion resistance (RCA abrasion), and steel wool rubbing.

During transfer at injection molding, untransferred areas may occur. The above-mentioned short (chip) refers to a region that cannot be transferred. Further, the burr means a portion where the transfer film protrudes around the transfer region without the transfer film being cut cleanly (that is, not cut as planned) at the boundary of the transfer region. Washout (pattern flow near the gate) means that the pattern printed near the gate to which high temperature and pressure are applied is partially lost. Whitening refers to a phenomenon in which the surface of a transfer film becomes cloudy white due to heat during injection molding. In addition, the flow pattern means that a flow mark is formed on the transfer film surface or the printed pattern due to the influence of the flow of the resin in the injection molding. Moreover, a crack means that a transfer film cannot follow the mold shape of injection molding and breaks. Further, delamination refers to a phenomenon in which a transfer film is delaminated between layers due to hot pressure during injection molding or a delamination operation. This delamination often occurs particularly between the protective layer and the adjacent layer.

Because of these diverse requirements, materials that can be used for the simultaneous decorative transfer film are materials that have a good balance of properties rather than materials that are particularly excellent in certain properties (for example, hardness, elongation, heat resistance). Is optimal. For example, a hard material gives good results with pencil hardness or steel wool rubbing, but is easily cracked and has low wear. On the other hand, a soft material can follow a deep-drawn shape without generating cracks, but is likely to cause whitening and burrs. In addition, although a material having high heat resistance can suppress washout, flow, and whitening, cracks are likely to occur and cannot follow a deep drawing shape. On the other hand, a material having low heat resistance can follow a deep drawing shape without causing cracks, but is liable to cause washout, flow, and whitening.

As described above, the materials used for the molded simultaneous decorative transfer film are often in a trade-off relationship with respect to various required properties and functions. As described above, in the technical field of simultaneous molding and decoration with many problems, the following several improvement proposals have been proposed.
In general, the post-curing physical properties of an ultraviolet curable resin often used as a protective layer (hard coat layer) tend to be hard and brittle, so that the hardness is high but the wear resistance tends to be weak. Among them, Patent Document 1 increases the wear resistance by cross-linking and toughening the ultraviolet curable resin of the hard coat layer with a polyisocyanate compound, but has the disadvantage that the film is difficult to break and burrs are likely to occur. appear. Therefore, in Patent Document 2, colloidal silica is put in the hard coat layer to make the film to be transferred fragile and to balance the burr countermeasure and the wear resistance.

However, it has been found that adding a polyisocyanate compound to the hard coat layer as in

Patent Documents

1 and 2 is a factor that inhibits the radical polymerizability of the ultraviolet curable resin, and reduces steel wool rubbing and pencil hardness. . Addition of a polyisocyanate compound to the hard coat layer also causes a large change in peel force (adhesiveness) when peeled between the release layer and the hard coat layer, and the peel performance over time is not stable.
On the other hand, in the case of a transfer film of an after cure type (a type in which the hard coat layer is cured by irradiating ultraviolet rays after transfer), depending on the material of the hard coat layer, blocking tends to occur. Therefore, blocking can be prevented by adding silica having a particle size of several microns to the material of the hard coat layer as an antiblocking agent. However, when silica of several microns is added to the hard coat layer, the surface gloss may be lowered. For this reason, Patent Document 3 proposes preventing blocking by providing a new anti-blocking layer without putting this silica in the hard coat layer. However, providing a new anti-blocking layer is not preferable because it leads to an increase in cost.

In addition, an ultraviolet curable resin is often used for the hard coat layer, but in this case, the hard coat layer and the decorative layer are often not sufficiently adhered. Therefore, in Patent Document 4, the primer layer includes two layers: a first primer layer made of urethane resin, an acrylic resin, and a polyisocyanate compound, and a second primer layer made of an acrylic resin formed thereon. By doing so, it has been proposed to maintain close contact with the decorative layer. Thus, it is necessary to customize the composition of the primer layer for each ultraviolet curable resin used for the hard coat layer, and in general, a specific primer layer is often required for a specific ultraviolet curable resin.

Japanese Patent Laid-Open No. 10-58895 JP 2009-137219 A JP 2009-291996 A Japanese Patent Laid-Open No. 5-278399

In the present invention, an object of the present invention is to provide a decorative transfer film that satisfies molding performance in injection molding and has excellent surface protection performance in simultaneous molding decoration.

The present invention has been intensively studied to solve the above-described problems, and is achieved by the following means.
One aspect of the present invention is a decorative transfer film of a type that is cured with ultraviolet light after transfer, wherein the decorative transfer film is formed on one surface of a support film, a release layer, a hard coat layer, a primer layer, A decorative printing layer and an adhesive layer are laminated in this order, and the composition of the hard coat layer is an acrylic acrylate resin having a weight average molecular weight in the range of 40,000 to 100,000 and containing a hydroxyl group. A tack-free material containing at least a UV initiator, silica particles having an average particle diameter of 10 nm to 100 nm, and polytetrafluoroethylene powder having an average particle diameter of 1 μm to 10 μm. The composition of the primer layer contains an acrylic polyol resin, a polyisocyanate compound, and a hydroxyl group. A decorative transfer film characterized in that it is a two-component curable resin containing at least a vinyl chloride / vinyl acetate copolymer resin.

In the decorative transfer film, the content of the polytetrafluoroethylene powder contained in the hard coat layer is within a range of 0.1 wt% to 2 wt% with respect to the acrylic acrylate resin. It is good to have done.
In the decorative transfer film, the content of the silica particles contained in the hard coat layer may be in the range of 10 wt% to 40 wt% with respect to the acrylic acrylate resin. .
In the decorative transfer film, a polyisocyanate compound may be further included in the hard coat layer.

In another aspect of the present invention, there is provided a decorative transfer film that is cured with ultraviolet rays after transfer, wherein the decorative transfer film is formed on one surface of a support film, a release layer, and a first hard coat. A layer, a second hard coat layer, a primer layer, a decorative printing layer, and an adhesive layer are laminated in this order, and the composition of the first hard coat layer has a weight average molecular weight of 40,000 to 100,000. Within the range, an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, silica particles having an average particle size in the range of 10 nm to 100 nm, and an average particle size in the range of 1 μm to 10 μm. A tack-free ultraviolet curable composition containing at least polytetrafluoroethylene powder and not containing a polyisocyanate compound, The composition of the coating layer has a weight average molecular weight in the range of 40,000 or more and 100,000 or less, an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle diameter in the range of 10 nm or more and 100 nm or less. A tack-free UV-curable composition containing at least particles and a polyisocyanate compound and not containing polytetrafluoroethylene powder, and the primer layer is composed of an acrylic polyol resin, a polyisocyanate compound, A decorative transfer film characterized in that it is a two-component curable resin containing at least a vinyl chloride-vinyl acetate copolymer resin containing a hydroxyl group.

In the decorative transfer film, the thickness of the first hard coat layer is in the range of 0.5 μm to 2.5 μm, and the thickness of the second hard coat layer is 3.0 μm or more. It is good also as having set it as the range of 8.0 micrometers or less.
In the decorative transfer film, the content of the polytetrafluoroethylene powder contained in the first hard coat layer may be 0.1 relative to the acrylic acrylate resin contained in the first hard coat layer. It may be in the range of not less than 2% by weight and not more than 2% by weight.
In the decorative transfer film, the silica particles contained in the first hard coat layer and the second hard coat layer are contained in the first hard coat layer and the second hard coat layer. It is good also as having made it in the range of 10 weight% or more and 40 weight% or less, respectively with respect to the said acrylic acrylate resin.

If it is one aspect of the present invention, short (chip), burr, washout (pattern flow near the gate), whitening, flow pattern, crack, Delamination film can be reduced compared with the prior art, and a transfer film that can satisfy adhesiveness with a molding resin necessary for surface protection performance, pencil hardness, abrasion resistance (RCA abrasion), and steel wool rubbing can be provided at low cost. It is possible.

It is sectional drawing which shows an example of the layer structure of the transfer film for decorating which concerns on embodiment of this invention. It is sectional drawing which shows the layer structure of the molding which transcribe | transferred the transfer film for decoration of FIG. It is sectional drawing which shows another example of the layer structure of the transfer film for decorating which concerns on embodiment of this invention. It is sectional drawing which shows the layer structure of the molded article which transcribe | transferred the transfer film for decoration of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same referential mark is attached | subjected to the component which exhibits the same or similar function, and the overlapping description is abbreviate | omitted.
FIG. 1 is a cross-sectional view illustrating an example of a layer configuration of a decorative transfer film according to an embodiment of the present invention. As shown in FIG. 1, the transfer film according to this embodiment is also referred to as a support film 1, a release layer 2, a hard coat layer 3, a primer layer 4, and a decorative print layer (hereinafter simply referred to as “decorative layer”). 5) A laminate comprising the adhesive layer 6 in this order. Here, the decoration layer 5 is usually a plurality of layers, and a decoration material having an optical effect such as embossing or pearl pigment can be used. FIG. 2 is a cross-sectional view showing a layer structure of a molded product obtained by transferring the decorative transfer film of FIG. 1, and molding after transferring the decorative transfer film according to the present embodiment at the same time as injection molding. It is sectional drawing of a thing. As shown in FIG. 2, the molded product includes an adhesive layer 6, a decorative layer 5, a primer layer 4, and a hard coat layer 3 in this order on a molding resin 7.

Although not clearly shown in the drawings, an antistatic layer may be provided on the surface of the support film 1 opposite to the release layer forming surface. By providing this antistatic layer, it is possible to reduce the adhesion of foreign matter to the transfer film, and the yield may be improved (in other words, the incidence of defective products may be reduced). The antistatic layer may be a resin layer containing an existing antistatic agent. For example, a conductive polymer such as ITO or antimony-doped tin, a quaternary ammonium salt, a surfactant, a conductive polymer such as polythiophene or PEDOT. , A layer containing a coating agent for a sol-gel reaction product.

Hereinafter, each layer of the decorative transfer film according to this embodiment will be described.
(Base film 1)
Examples of the base film 1 include polyethylene terephthalate film, polyethylene naphthalate film, polypropylene film, polyethylene film, triacetyl cellulose film, polycarbonate film, nylon film, cellophane film, acrylic film, polyvinyl chloride film, and PET-G film. The material can be used. The thickness of the usable film is in the range of 25 μm to 150 μm, and preferably in the range of 38 μm to 50 μm.

(Release layer 2)
The release layer 2 is most preferably peelable from the hard coat layer 3, but is also formed of a curable resin because heat resistance, solvent resistance, top coatability, and stretchability are also required. preferable. For this reason, as the release layer 2, for example, a cured product such as a melamine resin, a polyolefin resin, a urethane resin, or cellulose acetate can be used. Among the above materials, a release layer 2 using a melamine resin is usually used in many cases. However, when a melamine resin is used for the release layer 2, a baking step at a high temperature (140 to 200 ° C.) is required. And generates / contains harmful formaldehyde. Therefore, as a result of earnest research, the inventor has found that a cured product of a long-chain alkyl group-containing acrylic resin or / and a silicone-modified acrylic resin, an acrylic polyol resin, and a polyisocyanate compound is optimal as the release layer 2. I found it.
The thickness of the release layer 2 is not particularly limited, but is optimally in the range of 0.1 μm to 5 μm. Moreover, by making the release layer 2 contain a resin filler or an inorganic filler, it is possible to make it anti-glare or make the surface a mat.

(Hard coat layer 3)
The hard coat layer 3 is in a tack-free state, and is preferably formed of a resin that can be cross-linked by irradiating with ultraviolet rays or electron beams after being transferred to the transfer object. The reason for cross-linking after transfer is that the transfer film according to this embodiment is often used in injection molding or heat transfer method, but if cross-linked in advance, cracks are likely to occur during transfer stretching, resulting in poor appearance. is there.
There are mainly the following three methods for realizing tack-free properties before transfer. The first method is a method using a polymer acrylate or methacrylate. The second method is a method in which a liquid or semi-liquid UV curable resin is slightly cured using a cross-linking resin such as isocyanate / polyol resin or epoxy resin / amines to make it tack-free. The third method is a method in which the hard coat layer 3 is slightly irradiated with ultraviolet rays or an electron beam to be in a semi-cured state.
In the present embodiment, the first method is used. The reason is that in the second method, the adhesiveness with the release layer 2 is too high, and the peelability as a transfer film becomes insufficient. In the third method, the intensity variation (specifically, the intensity variation of the irradiated ultraviolet ray or electron beam) and the reproducibility of the ultraviolet ray irradiator and the electron beam irradiator are problematic, and the process cost is also high. high.

In the case of using the first method, in order to prevent tackiness and to prevent the resin from flowing during injection molding, the weight average molecular weight is in the range of 40,000 to 100,000 and the glass transition temperature is 60 ° C. It is preferable to use an acrylic resin (acrylic acrylate resin) containing the above acryloyl group or methacryloyl group. In other words, the acrylic acrylate resin contained in the hard coat layer 3 preferably has a weight average molecular weight in the range of 40,000 to 100,000 and contains a hydroxyl group. When the weight average molecular weight is less than 40,000, tack-free property is not sufficient, there is a problem in top coatability, and washout is likely to occur during molding. On the other hand, when the weight average molecular weight exceeds 100,000, the radical reactivity is lowered and the hardness at the time of crosslinking may not be increased. In addition, the range of the optimal weight average molecular weight of acrylic acrylate resin is 60,000 or more and 80,000 or less.

Compared to oligomers and monomers that are generally used as UV curable resins, such acrylic acrylate resins have advantages such as tack-free properties (no stickiness by simply evaporating the solvent) and less curing shrinkage. On the other hand, since it is a polymer resin, its ultraviolet curability tends to be inferior. Therefore, in order to compensate for the poor surface hardness of the hard coat layer 3, it is necessary to add nano silica particles to the acrylic acrylate resin. If the amount added is less than 10% by weight based on the acrylic acrylate resin, no effect on hardness is observed. On the other hand, if it exceeds 40% by weight, it becomes too brittle and the wear resistance is poor. For this reason, the optimal addition amount of a nano silica particle exists in the range of 10 to 40 weight% with respect to acrylic acrylate resin. Moreover, the range of the optimal addition amount of nano silica particle amount is 15 to 35 weight%.

The above-mentioned weight average molecular weight is a value calculated by styrene conversion by GPC (gel permeation chromatography) measurement.
The nanosilica particles added to the hard coat layer 3 preferably have a particle diameter in the range of 10 nm to 100 nm in order to maintain transparency. In addition, the nanosilica particles are desirably surface-treated with a silane coupling agent containing an acryloyl / methacryloyl group or the like, but may be simply untreated nanosilica particles.
When the main composition of the hard coat layer 3 is an acrylic acrylate resin and nano silica particles, the resistance of the steel wool test is excellent due to the hardness of the outermost surface, but the wear resistance (particularly RCA wear) is due to its brittleness. Prone to bad results. However, by adding polytetrafluoroethylene powder having an average particle diameter of 1 μm or more and 10 μm or less within a range of 0.1% by weight or more and 2% by weight or less with respect to the acrylic acrylate resin, the above abrasion resistance Can be improved. If the average particle size of the added polytetrafluoroethylene powder is less than 1 μm, the dispersibility is poor and handling is difficult. Moreover, when the average particle diameter of the added polytetrafluoroethylene powder exceeds 10 μm, it is difficult to hold in the hard coat layer 3, the polytetrafluoroethylene powder is easily detached, and the hard coat layer 3 has a scattering property. Since it becomes high, it is not preferable. A more preferable range of the average particle diameter of the polytetrafluoroethylene powder is 2 μm or more and 7 μm or less.

In addition, when the amount of polytetrafluoroethylene powder added is less than 0.1% by weight with respect to the acrylic acrylate resin, the effect of wear resistance is insufficient, and when it exceeds 2% by weight, scattering properties appear. Since transparency falls, it is unpreferable. For this reason, the preferable range of the addition amount of polytetrafluoroethylene powder is 0.1 wt% or more and 2 wt% or less. More preferably, it is in the range of 0.2 wt% or more and 1 wt% or less.
When the decorative transfer film according to this embodiment is manufactured, all layers from the hard coat layer 3 to the adhesive layer 6 except the release layer 2 (that is, the hard coat layer 3, the primer layer 4, and the decoration). It is preferable to apply and print the layer 5 and the adhesive layer 6) in-line. However, the hard coat layer 3 to which polytetrafluoroethylene powder is added has a high anti-blocking effect. Therefore, after the hard coat layer 3 is applied, Winding and temporary storage are also possible.

The wear resistance of the hard coat layer 3 can also be improved by adding a metal soap such as polyethylene wax or zinc stearate to the hard coat layer 3. However, since the addition of the above-described metal soap does not show a remarkable effect unless it is added more than 10 times the addition amount of the polytetrafluoroethylene powder, and many of the particles have a relatively large particle size, the hard coat layer 3 This is not suitable because it tends to cause a decrease in hardness and transparency.
By adding a small amount of a polyisocyanate compound to the hard coat layer 3 and crosslinking it, it is possible to improve the toughness of the film and reduce the falling of the foil (the foil peels off during the manufacturing process). However, depending on the amount of the polyisocyanate compound added, peeling failure may be caused, burrs or chips (shorts) may be caused, and pencil hardness and steel wool rubbing may also be bad results. Therefore, the preferable addition amount of the polyisocyanate compound is in the range of 5% by weight or less with respect to the acrylic acrylate resin.

Next, FIGS. 3 and 4 will be described. FIG. 3 is a cross-sectional view showing another example of the layer configuration of the decorative transfer film according to the embodiment of the present invention. As shown in FIG. 3, the transfer film according to the present embodiment includes a support film 1, a release layer 2, a first hard coat layer 8, a second hard coat layer 9, a primer layer 4, a decorative layer 5, and an adhesive layer. 6 is a laminated body provided with this order. FIG. 4 is a cross-sectional view showing the layer structure of the molded product to which the decorative transfer film of FIG. 3 is transferred, and is a cross-sectional view of the molded product to which the decorative transfer film according to this embodiment is transferred. is there. As shown in FIG. 4, the molded product includes an adhesive layer 6, a decorative layer 5, a primer layer 4, a second hard coat layer 9, and a first hard coat layer 8 in this order on a molding resin 7. ing.

The decorative transfer film shown in FIG. 3 is different from the decorative transfer film shown in FIG. 1 in that the first hard coat layer 8 and the second hard coat layer 9 are provided. Therefore, the first hard coat layer 8 and the second hard coat layer 9 will be described next.
The first hard coat layer 8 has a weight average molecular weight in the range of 40,000 to 100,000, and an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle diameter in the range of 10 nm to 100 nm. A tack-free UV-curable composition containing at least silica particles and a polytetrafluoroethylene powder having an average particle diameter of 1 μm or more and 10 μm or less and containing no polyisocyanate compound.

The second hard coat layer 9 has a weight average molecular weight in the range of 40,000 to 100,000, and an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle size in the range of 10 nm to 100 nm. It is a tack-free ultraviolet curable composition containing at least silica particles and a polyisocyanate compound, and containing no polytetrafluoroethylene powder.
Thus, the hard coat layer of this embodiment may be composed of two or more layers. In this case, as described above, the first hard coat layer 8 adjacent to the release layer 2 preferably contains polytetrafluoroethylene powder and does not contain a polyisocyanate compound. Further, the second hard coat layer 9 adjacent to the first hard coat layer 8 preferably does not contain polytetrafluoroethylene powder and contains a polyisocyanate compound. This is because of the following three reasons.

The first reason is as follows.
When the coating liquid for hard coat layer is applied and dried on the release layer 2, the nanosilica particles contained in the hard coat layer tend to be unevenly distributed on the surface opposite to the release layer 2 (that is, the air surface). is there. Therefore, there are few nano silica particle components on the side that becomes the outermost surface after transfer, and as a result, steel wool resistance and pencil hardness do not increase. Therefore, the influence of uneven distribution of nanosilica particles can be reduced by dividing the hard coat layer into two or more layers and making the first hard coat layer 8 as the outermost layer as thin as possible.

The second reason is as follows.
In order to improve adhesion between the hard coat layer and the primer layer 4, it is preferable to add a polyisocyanate compound to the hard coat layer, but a polyisocyanate compound is added to the hard coat layer in contact with the release layer 2. And peelability (adhesiveness with the release layer) may change with time, or may cause peeling failure during transfer. Further, when a polyisocyanate compound is added to the first hard coat layer 8 that becomes the outermost surface after transfer, the radical reactivity of the ultraviolet curable resin is inhibited, and the surface hardness (particularly, steel wool resistance) is likely to be lowered. Therefore, the first hard coat layer (outermost layer) 8 in contact with the release layer 2 is not added with a polyisocyanate compound, but is added to the second hard coat layer 9 on the primer layer 4 side to balance the hardness and adhesion. A transfer film can be obtained.

The third reason is as follows.
When the primer layer 4 is overcoated on the hard coat layer containing polytetrafluoroethylene powder, the primer layer coating solution may be repelled or the interlayer adhesion may be insufficient. Therefore, polyfluoroethylene powder is added to the first hard coat layer 8 and the second hard coat layer 9 not containing the polyfluoroethylene powder is applied with a coating amount set larger than that of the first hard coat layer 8. Therefore, the repellency of the primer layer coating solution is prevented and the adhesion is improved.

Here, the content of the polytetrafluoroethylene powder contained in the first hard coat layer 8 is within the range of 0.1 wt% or more and 2 wt% or less with respect to the acrylic acrylate resin contained in the first hard coat layer 8. It is preferable that
Further, the content of the silica particles contained in the first hard coat layer 8 and the second hard coat layer 9 is 10 with respect to the acrylic acrylate resin contained in the first hard coat layer 8 and the second hard coat layer 9, respectively. It is preferable to be in the range of not less than 40% by weight.
The thickness of the first hard coat layer 8 is preferably in the range of 0.5 μm to 2.5 μm, and the thickness of the second hard coat layer 9 is in the range of 3.0 μm to 8.0 μm. It is preferable.

When the thickness of the 1st hard-coat layer 8 is less than 0.5 micrometer, holding | maintenance of polytetrafluoroethylene powder is difficult, and there exists a danger which stains the guide roll and nip roll of a coating apparatus. Moreover, when the thickness of the 1st hard-coat layer 8 exceeds 2.5 micrometers, the effect of the uneven distribution measure of a nano silica particle is low.
When the thickness of the second hard coat layer 9 is less than 3.0 μm, the total thickness of the hard coat layer including the first hard coat layer 8 is thin, and the hardness as the hard coat layer is sufficient for reasons such as oxygen inhibition. It cannot be demonstrated. Further, the effect of preventing the repellency of the primer layer coating solution is also reduced. When the second hard coat layer 9 exceeds 8.0 μm, not only the cost is increased, but also the toughness becomes too strong and burrs are easily generated, which is not preferable.

Since the first hard coat layer 8 is thin, the amount of nanosilica particles can be increased as compared with the case where the hard coat layer is formed as a single layer, and the transparency is slightly reduced but the steel wool resistance is reduced. It is also possible to add nano-alumina particles that are highly effective.
The acrylic acrylate resin is a polymer having radical reactivity obtained by further pendating a (meth) acryloyl group on a (meth) acrylic copolymer made of various (meth) acryloyl monomer copolymers. By changing the kind and ratio of the (meth) acryloyl monomer to be polymerized, various physical properties of the coating film can be expressed. In general, oligomers such as urethane acrylate, epoxy acrylate, and polyester acrylate used for ultraviolet curable resins have a weight average molecular weight of hundreds to thousands, whereas acrylic acrylate resins have thousands to hundreds of thousands. Yes, it has different characteristics such as low shrinkage and tack-free property when uncured.

Monomer components constituting the acrylic acrylate resin include mono / polyfunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylprolidone, trimethylolpropane (meth) acrylate, hexane Diol (meth) acrylate, diethylene glycol (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, etc. is there.

Here, the polyisocyanate compound refers to toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and prepolymers thereof.
Further, the ultraviolet initiator is an initiator that generates radicals by ultraviolet rays. Examples of those that can be blended in this embodiment include benzophenone, diethylthioxanthone, benzyldimethyl ketal, 2-hydroxy-2-methyl-1- Examples include phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1, acylphosphine oxide. The ultraviolet initiator is not particularly limited in use, but is preferably selected according to the wavelength of the irradiation light of the ultraviolet irradiation device used when the hard coat layer 3 is cured. Although the addition amount of a ultraviolet initiator changes with kinds of ultraviolet initiator, it is preferable to set it as the inside of the range of 1 weight% or more and 10 weight% or less with respect to acrylic acrylate resin.

(Primer layer 4)
The primer layer 4 is a layer for maintaining adhesion between the hard coat layer 3 (or the second hard coat layer 9) and the decorative layer 5, and as a result of earnest research, the inventor has found that an acrylic polyol resin and a hydroxyl group are contained. It has been found that a resin comprising a vinyl chloride vinyl acetate copolymer resin and a polyisocyanate compound is preferable. More specifically, the primer layer 4 is a two-part curable resin containing at least a resin composed of an acrylic polyol resin, a polyisocyanate compound, and a hydroxyl group-containing vinyl chloride / vinyl acetate copolymer resin. Further, by adding an extender pigment such as silica, barium sulfate, or calcium carbonate to the primer layer 4, the inking property of the coating liquid for the decorative layer is improved. Moreover, since burr | flash can be decreased, it is optimal to add the above-mentioned extender pigment within the range of 5 wt% to 20 wt% with respect to the acrylic polyol resin.

The acrylic polyol resin tends to generate burrs when the glass transition temperature is lower than 50 ° C., and when the glass transition temperature exceeds 90 ° C., the acrylic polyol resin tends to be difficult to adhere to the hard coat layer 3. For this reason, it is desirable that the acrylic polyol resin used in the present embodiment has a glass transition temperature in the range of 50 ° C. or higher and 90 ° C. or lower.
The vinyl chloride vinyl acetate copolymer resin can be reacted with a polyisocyanate compound by using a hydroxyl group-containing vinyl chloride vinyl acetate copolymer resin modified with vinyl alcohol or hydroxyalkyl acrylate, and adhesion is improved. In the primer layer 4, it is desirable that this hydroxyl group-containing vinyl chloride vinyl acetate copolymer resin is blended in the range of 10 wt% to 60 wt% with respect to the acrylic polyol resin. Further, the thickness of the primer layer 4 is not particularly limited, but is optimal within the range of 0.5 μm or more and 4 μm or less.

(Decoration layer 5)
The decorative layer 5 is not particularly different in material compared to the above layers. The decoration techniques that can be used in the formation of the decoration layer 5 include not only general printing with colored coating liquids, but also special printing such as pearl, fluorescence, mirror, retroreflection, and magnetic printing, and unevenness caused by heat and ultraviolet rays. Examples include embossing for forming structures (various lens effects and holograms), and thin film forming techniques for forming aluminum, silver, chromium, titanium oxide, zinc sulfide, and the like by vacuum deposition or sputtering.
The decorative layer 5 is usually two or more layers, for example, black pattern printing layer / white presser layer, pearl layer / black printing layer, red pattern printing layer / mirror ink layer, indigo pattern / emboss layer / tin vapor deposition layer, etc. For example, when considering design properties, or improving the quality of missing prints and separating the functionality (in this case, adhesion, such as black solid printing layer (with curing agent) / black solid printing layer / black solid printing layer). To meet the various requirements, etc.).

(Adhesive layer 6)
As the adhesive layer 6, a known heat-sealable adhesive or pressure-sensitive adhesive can be used. Examples of the adhesive layer 6 include vinyl acetate resin, ethylene vinyl acetate copolymer resin, vinyl acetate resin, acrylic resin, butyral resin, epoxy resin, polyester resin, polyurethane resin, acrylic adhesive, rubber adhesive, and silicone. Type adhesive, urethane type adhesive and the like. The thickness of the adhesive layer 6 is optimally in the range of 0.5 μm to 10 μm.

An existing coating / printing method can be adopted as a method for forming each layer in the present embodiment. Examples of the method for forming each layer of the present embodiment include direct gravure, gravure reverse, micro gravure, roll coat, curtain coat, die coat, spray coat, Mayer coat, comma coat, screen printing, flexographic printing, and the like. The drying condition of the coating solution depends on the solvent used, but it is usually sufficient to dry it for 2 to 60 seconds in an environment of 80 to 150 ° C. However, depending on the thickness of the coating solution and the type of coating solution, additional drying may be necessary for several tens of seconds with heat of 120 ° C. to 180 ° C. in order to reduce the residual solvent and accelerate the two-component curing reaction.

The transfer film of this embodiment is formed by coating the release layer 2, the hard coat layer 3, the primer layer 4, the decorative layer 5, and the adhesive layer 6, which are made of the above composition, in order by the coating / printing method. It is manufactured by.
The transfer film of the present embodiment produced in this way can be transferred to the surface of the molded article by the hot pressure of injection molding by being inserted into a mold during injection molding. Note that the peeling interface is an interface between the release layer 2 and the hard coat layer 3 (or the second hard coat layer 9). After transferring to the surface of the molded product, the hard coat layer 3 (or the second hard coat layer 9) is cured by irradiating with an exposure dose of about 500 to 1500 mJ / cm ^{2 with} a high pressure mercury lamp or a metahalide lamp. By doing so, it is possible to obtain a molded product satisfying various physical properties (steel wool test, pencil hardness, etc.).

Next, the present invention will be described more specifically with reference to examples.
<Example 1>
On a biaxially stretched polyester film (G440E50 manufactured by Mitsubishi Plastics) with a thickness of 50 μm, the release layer coating solution formulated as follows was applied and dried by a microgravure method so that the film thickness after drying was 0.4 μm. did. Thereafter, the release layer 2 was formed by aging in an environment of 50 ° C. for 5 days.
・ Release layer coating solution Toei Kasei Co., Ltd. acrylic polyol LC # 6560 ... 100 parts by weight NOF silicone modified acrylic resin FS730 ... 20 parts by weight Nippon Polyurethane isocyanate compound coronate L ... 20 parts by weight Subsequently, the following hard coat layer coating solution as a hard coat layer 3 was applied and dried by a microgravure method so that the film thickness after drying was 5.0 μm. Then, this film was wound up. This film was stored for 30 days in an environment of 40 ° C., but no blocking occurred.

-Hard coat layer coating solution DIC tack-free UV curable resin (with UV polymerization initiator) 30% solids
RC29-117 ... 100 parts by weight Silica manufactured by Nissan Chemical (particle size 10-20nm) MEK dispersion (solid content 30%)
... 20 parts by weight Asahi Glass Polyfluoroethylene Powder L173J (particle size 7 μm, solid content 100%) ... 0.3 parts by weight Subsequently, this film is formulated as a primer layer coating solution as follows: The primer layer coating solution thus prepared was applied by a direct gravure method so that the film thickness after drying was 1.0 μm.

・ Acrylic polyol YB # 7004 manufactured by Toei Kasei Co., Ltd. for primer layer: 100 parts by weight Hydroxyl acrylate modified vinyl chloride vinyl acetate copolymer resin manufactured by Nissin Chemical Co., Ltd. Solvain TA2 L · ·· 20 parts by weight Subsequently, printing is performed with a predetermined decorative layer coating solution, and the adhesive layer 6 is coated with an adhesive layer coating solution (K539HP adhesive varnish manufactured by Toyo Ink) with a gravure method to obtain a film thickness after drying. The adhesive layer 6 was formed by coating to 1 μm.
Subsequently, the decorated transfer film was set inside the mold of an injection molding machine, and injection molding was performed using polycarbonate / ABS alloy resin. In this way, a molded product obtained by transferring the transfer film of this example was obtained.

<Example 2>
On a biaxially stretched polyester film (G440E50 manufactured by Mitsubishi Plastics) with a thickness of 50 μm, the release layer coating solution formulated as follows was applied and dried by a microgravure method so that the film thickness after drying was 0.4 μm. did. Thereafter, the release layer 2 was formed by aging in an environment of 50 ° C. for 5 days.
・ Release layer coating solution Toei Kasei Co., Ltd. acrylic polyol LC # 6560 ... 100 parts by weight NOF silicone modified acrylic resin FS730 ... 20 parts by weight Nippon Polyurethane isocyanate compound coronate L ... 20 parts by weight Subsequently, the following first hard coat layer coating solution was applied and dried as a first hard coat layer 8 by a microgravure method so that the film thickness after drying was 1.0 μm. Thereafter, the following coating solution for the second hard coat layer was applied and dried by a microgravure method so that the film thickness after drying was 2.0 μm. Then, this film was wound up. This film was stored for 30 days in an environment of 40 ° C., but no blocking occurred.

-First hard coat layer coating solution DIC Tack-free UV curable resin (with UV polymerization initiator) 30% solids
RC29-117 ... 100 parts by weight Silica manufactured by Nissan Chemical (particle size 10-20nm) MEK dispersion (solid content 30%)
・・・・ 20 parts by weight Asahi Glass polyfluoroethylene powder L173J (particle size 7 μm, solid content 100%) ・・・ 0.3 parts by weight ・ Tack-free UV curable resin made of DIC for second hard coat layer coating (UV) 30% solid content with polymerization initiator)
RC29-117 ... 100 parts by weight Silica manufactured by Nissan Chemical (particle size 10-20nm) MEK dispersion (solid content 30%)
··· 20 parts by weight Nippon Polyurethane isocyanate compound coronate HL ··· 5 parts by weight Subsequently, as a primer layer coating solution, a primer layer coating solution formulated as follows was applied by direct gravure method. It applied so that the film thickness after drying might be set to 1.0 micrometer.

・ Acrylic polyol YB # 7004 manufactured by Toei Kasei Co., Ltd. for primer layer: 100 parts by weight Hydroxyl acrylate-modified vinyl chloride vinyl acetate copolymer resin manufactured by Nissin Chemical Co., Ltd. BIC 200 2 parts by weight Nippon Polyurethane Isocyanate Compound Coronate L 20 parts by weight Subsequently, printing is performed with a predetermined decorative layer coating solution, and adhesive layer 6 is applied as an adhesive layer coating solution (Toyo Ink K539HP adhesive varnish) was applied by a gravure method so that the film thickness after drying was 1 μm to form an adhesive layer 6.
Subsequently, the decorated transfer film was set inside the mold of an injection molding machine, and injection molding was performed using polycarbonate / ABS alloy resin. In this way, a molded product obtained by transferring the transfer film of this example was obtained.

<Comparative Example 1>
On a biaxially stretched polyester film (G440E50 manufactured by Mitsubishi Plastics) with a thickness of 50 μm, the release layer coating solution formulated as follows was applied and dried by a microgravure method so that the film thickness after drying was 0.2 μm. did. Thereafter, the release layer 2 was formed by aging in an environment of 50 ° C. for 5 days.
・ Release layer coating solution Toei Kasei Co., Ltd. acrylic polyol LC # 6560 ... 100 parts by weight NOF silicone modified acrylic resin FS730 ... 20 parts by weight Nippon Polyurethane isocyanate compound coronate L ... 20 parts by weight Subsequently, the following hard coat layer coating solution was applied and dried as a hard coat layer 3 by a microgravure method so that the film thickness after drying was 6.0 μm. Then, this film was wound up. When this film was stored in an environment of 40 ° C. for 30 days, blocking occurred and the film could not be used.

-Hard coat layer coating solution DIC tack-free UV curable resin (with UV polymerization initiator) 30% solids
RC29-117 ... 100 parts by weight Silica manufactured by Nissan Chemical (particle size 10-20nm) MEK dispersion (solid content 30%)
・・・・ 30 parts by weight Nippon Polyurethane Isocyanate Compound Coronate HL 10 parts by weight Subsequently, the primer layer coating solution formulated as follows is dried on the film by the direct gravure method. The subsequent film thickness was applied to 1.0 μm.

・ Acrylic polyol YB # 7004 manufactured by Toei Kasei Co., Ltd. for primer layer: 100 parts by weight Hydroxyl acrylate-modified vinyl chloride vinyl acetate copolymer resin manufactured by Nissin Chemical Co., Ltd. BIC 200 2 parts by weight Nippon Polyurethane Isocyanate Compound Coronate L 20 parts by weight Subsequently, printing is performed with a predetermined decorative layer coating solution, and adhesive layer 6 is applied as an adhesive layer coating solution (Toyo Ink K539HP adhesive varnish) was applied by a gravure method so that the film thickness after drying was 1 μm to form an adhesive layer 6.
Subsequently, the decorated transfer film was set inside the mold of an injection molding machine, and injection molding was performed using polycarbonate / ABS alloy resin. In this way, a molded product obtained by transferring the transfer film of this comparative example was obtained.

<Comparative example 2>
On a biaxially stretched polyester film (G440E50 manufactured by Mitsubishi Plastics) with a thickness of 50 μm, the release layer coating solution formulated as follows was applied and dried by a microgravure method so that the film thickness after drying was 0.6 μm. did. Thereafter, the release layer 2 was formed by aging in an environment of 50 ° C. for 5 days.
・ Release layer coating solution Toei Kasei Co., Ltd. acrylic polyol LC # 6560 ... 100 parts by weight NOF silicone modified acrylic resin FS730 ... 20 parts by weight Nippon Polyurethane isocyanate compound coronate L ... 20 parts by weight Subsequently, the following hard coat layer coating solution was applied and dried as a hard coat layer 3 by a microgravure method so that the film thickness after drying was 6.0 μm. Then, this film was wound up.

-Hard coat layer coating solution DIC tack-free UV curable resin (with UV polymerization initiator) 30% solids
RC29-117 ... 100 parts by weight Silica manufactured by Nissan Chemical (particle size 10-20nm) MEK dispersion (solid content 30%)
··· 20 parts by weight Subsequently, an acrylic polyol / isocyanate coating solution (V425 anchor manufactured by Toyo Ink) was applied to this film as a primer layer 4 by a gravure method so that the film thickness after drying was 2 μm. Thereafter, printing is performed with a predetermined decorative layer coating liquid, and the adhesive layer coating liquid (K539HP adhesive varnish made by Toyo Ink) is applied as the adhesive layer 6 so that the film thickness after drying is 1 μm by the gravure method, An adhesive layer 6 was formed.
Subsequently, the decorated transfer film was set inside the mold of an injection molding machine, and injection molding was performed using polycarbonate / ABS alloy resin. In this way, a molded product obtained by transferring the transfer film of this comparative example was obtained.

The molded products obtained in Example 1, Example 2, Comparative Example 1, and Comparative Example 2 were irradiated with ultraviolet light having an exposure amount of 1000 mJ / cm ² with a 120 W / cm high-pressure mercury lamp, and hard coat layer 3 (or second product) The hard coat layer 9) was completely cured. Next, evaluation items and evaluation criteria for these molded products are shown below.
(Bari)
○: There is no burr.
Δ: There are burrs of less than 5 mm.
X: There are burrs of 5 mm or more.
(short)
○: No short circuit at all.
Δ: There is a short of less than 5 mm.
X: There is a short of 5 mm or more.
(crack)
○: There is no crack.
X: There is a crack.
(Washout)
○: There is no washout.
Δ: There is a washout of less than 1 mm.
×: There is a washout of 1 mm or more.
(Ryumon)
○: The flow mark cannot be confirmed.
X: The trace which flowed can be confirmed.
(Whitening)
○: There is no surface roughness.
X: The surface is rough.
(Delamination)
○: No peeling.
X: There is peeling.
(Adhesion test)
This test is based on the adhesive crosscut method of JIS K5600-5-6.
○: Not peeled off at all.
Δ: The peeled state is 2 or less.
X: The peeled state is 3 or more.
(Pencil hardness test)
This test is in accordance with JIS K5600-5-4.
(Steel wool rubbing)
The surface after reciprocating and rubbing 5 times at a load of 500 g / cm ² and a speed of 30 mm / sec on # 0000 steel wool was visually observed and evaluated by the following ○ to ×.
○: Almost no scratches are visible.
Δ: There are 20 or less scratches.
X: Appears as a white scattered surface.

(RCA wear test)
This test is based on the test of ASTM F2357-04.
It was observed visually after 200 counts in a continuous test at 175 g load, and evaluated by the following ○ to ×.
○: Scratches are hardly visible.
(Triangle | delta): It has shaved but the base is not exposed.
X: The base is exposed.
Table 1 shows the evaluation results of each example and each comparative example.

From the results in Table 1, it can be seen that Example 1 and Example 2, which are examples of embodiments of the present invention, exhibit balanced performance in each evaluation item.

The transfer film obtained by the present invention can be used for surface protection and decoration of casings and panel members used for home appliances, housing equipment, office equipment, automobile parts and the like.

DESCRIPTION OF SYMBOLS 1 ... Support film, 2 ... Release layer, 3 ... Hard coat layer, 4 ... Primer layer, 5 ... Decorating layer, 6 ... Adhesive layer, 7 ... Molding resin, 8 ... 1st hard coat layer, 9 ... 2nd Hard coat layer

Claims

In the decorative transfer film that is cured with ultraviolet light after transfer,
The decorative transfer film is formed by laminating a release layer, a hard coat layer, a primer layer, a decorative printing layer, and an adhesive layer in this order on one surface of a support film,
The composition of the hard coat layer has a weight average molecular weight in the range of 40,000 to 100,000, and an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle diameter in the range of 10 nm to 100 nm. A tack-free UV-curable composition comprising at least silica particles and a polytetrafluoroethylene powder having an average particle diameter in the range of 1 μm to 10 μm,
A decorative transfer film, wherein the composition of the primer layer is a two-component curable resin containing at least an acrylic polyol resin, a polyisocyanate compound, and a vinyl chloride-vinyl acetate copolymer resin containing a hydroxyl group.
The content of the polytetrafluoroethylene powder contained in the hard coat layer is within a range of 0.1 wt% or more and 2 wt% or less with respect to the acrylic acrylate resin. Transfer film for decoration.
The content of the silica particles contained in the hard coat layer is in the range of 10 wt% or more and 40 wt% or less with respect to the acrylic acrylate resin. Transfer film for decoration.
The decorative transfer film according to any one of claims 1 to 3, further comprising a polyisocyanate compound in the hard coat layer.
In the decorative transfer film that is cured with ultraviolet light after transfer,
Lamination layer, first hard coat layer, second hard coat layer, primer layer, decorative print layer and adhesive layer are laminated in this order on one surface of the support film. Shall be
The composition of the first hard coat layer has a weight average molecular weight in the range of 40,000 to 100,000, and an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle size of 10 nm to 100 nm. A tack-free ultraviolet curable composition containing at least silica particles in the range and polytetrafluoroethylene powder having an average particle diameter in the range of 1 μm or more and 10 μm or less and containing no polyisocyanate compound. ,
The composition of the second hard coat layer has a weight average molecular weight in the range of 40,000 or more and 100,000 or less, an acrylic acrylate resin containing a hydroxyl group, an ultraviolet initiator, and an average particle diameter of 10 nm or more and 100 nm or less. A tack-free UV-curable composition containing at least silica particles and a polyisocyanate compound and not containing polytetrafluoroethylene powder,
A decorative transfer film, wherein the composition of the primer layer is a two-component curable resin containing at least an acrylic polyol resin, a polyisocyanate compound, and a vinyl chloride-vinyl acetate copolymer resin containing a hydroxyl group.
The layer thickness of the first hard coat layer is in the range of 0.5 μm to 2.5 μm,
6. The decorative transfer film according to claim 5, wherein the second hard coat layer has a layer thickness in a range of 3.0 μm or more and 8.0 μm or less.
The content of the polytetrafluoroethylene powder contained in the first hard coat layer is within the range of 0.1 wt% or more and 2 wt% or less with respect to the acrylic acrylate resin contained in the first hard coat layer. The decorative transfer film according to claim 5 or 6, wherein the decorative transfer film is a decorative film.
The content of the silica particles contained in the first hard coat layer and the second hard coat layer is 10 with respect to the acrylic acrylate resin contained in the first hard coat layer and the second hard coat layer, respectively. The decorative transfer film according to any one of claims 5 to 7, wherein the transfer film is in a range of not less than 40% by weight and not more than 40% by weight.