JP2002293094A - Transfer sheet and manufacturing method for laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laminate, adhesion between a transfer layer and a covering body of which is strong, though the peelability between the base sheet of the transfer sheet and the transfer layer is kept during the process for obtaining the laminate, in manufacturing the laminate having the transfer layer is sandwiched between a body to be transferred and the covering body. SOLUTION: In the transfer sheet, on the base sheet of which, a peel ply and the transfer sheet including a pattern layer are provided through a releasing layer, the peel ply is made of a resin including an olefin-based resin and the releasing layer is made of a rein including an epoxy resin or/and melamine resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer sheet used to obtain a laminate having a good adhesion between a transfer layer of a laminate and a cover, and a transfer object and a cover using the transfer sheet. And a method for manufacturing a laminate in which a laminate in which a transfer layer is interposed is obtained. In particular, cosmetic containers, electrical appliances,
The present invention is suitable as a transfer sheet used for obtaining a laminate having a design such as a household article and a method for producing the laminate.

[0002]

2. Description of the Related Art Conventionally, there is a transfer method as a method of forming a picture on the surface of an article such as a plate. The transfer method is a release layer,
Using a transfer sheet having a transfer layer including a picture layer provided on a base sheet, applying heat and pressure to bring the transfer layer into close contact with the object to be transferred, and then peeling the base sheet to expose the release layer of the transfer layer. It is a method of forming a product that has become a new product.

[0003] When the object to be transferred is a resin molded product, there is a simultaneous molding transfer method as a method for performing the transfer method more rationally. With simultaneous molding transfer method, a transfer sheet is sandwiched in a molding die, resin is injected and filled on the transfer layer side of the transfer sheet, and cooled to obtain a molded product, and at the same time, the transfer sheet is bonded to the surface of the molded product. Then, the base sheet is peeled off to form a product in which the release layer of the transfer layer is exposed.

However, since the transfer layer of the product obtained by the above method is exposed to the outside, it is necessary to harden the release layer, which is the outermost surface layer of the transfer layer, in order to have strength against friction and scratching. For example, a method of overcoating a transfer layer after transfer with a resin by a coating method has been adopted. However, even if these methods are employed, there is a limit in terms of strength against friction and scratching, and therefore, a method having a higher strength has been desired.

[0005] Therefore, a method of covering the exposed transfer layer with an injection molding resin (molding resin for coating) is considered. As a specific method, there is a molding method in which a transfer target body on which a transfer layer transferred from a transfer sheet is formed is placed in a molding die, and the transfer layer is molded by injecting and filling a molten coating molding resin. Conceivable.

[0006]

However, this molding method has a problem that the adhesion between the release layer of the transfer layer and the molding resin for coating is weak. For example, when the release layer of the transfer sheet is an acrylic resin and the molding resin for coating is a polypropylene resin, the two are incompatible resins and therefore have a weak adhesive force and easily peel off. Also, due to the weak adhesion between the release layer of the transfer layer and the molding resin for coating, a pinhole-shaped void is generated at the interface between the release layer and the molding resin for coating, and when heat is applied to the molded product, There is also a problem that the gap expands and becomes large and the appearance deteriorates.

[0007] In order to strengthen the adhesion between the release layer of the transfer sheet and the molding resin for coating, the release layer can be formed of a resin containing an olefinic resin. Then, the release layer and the base sheet are separated. A new problem will arise. For example, when the base sheet of the transfer sheet is a polyethylene terephthalate resin and the release layer is an olefin-based resin, since both resin systems are the same, the peeling weight becomes larger than that of a normal transfer material, which causes inconvenience. You. As a disadvantage when the peeling weight is large, there is a problem that, when the base sheet is peeled, the transfer layer partially remains on the base sheet side and is not transferred. Pressure 1 by silicon rubber roller
The pattern layer side of the transfer sheet was adhered to the transfer object under the transfer conditions of 4.7 N / square cm (1.5 kgf / square cm), a heating temperature of 220 ° C. by a silicon rubber roller, and a peeling speed of the base sheet of 3 m / min. Thereafter, a 25 mm-wide cellophane adhesive tape (JIS 2) was applied to the base sheet of the transfer sheet.
152Z), one end of which is adhered and the other end is supported by a spring balance, and a support base and a cellophane adhesive tape (JIS 2152)
Z) always keeps an angle of 45 degrees and 1
Cellophane adhesive tape (JIS 21) at a speed of 5 mm / sec.
52Z), when the weight (peeling weight) of the spring scale when pulling was measured, the peeling weight between the release layer and the peeling layer was 0.294.
There is a numerical value exceeding N / 25 mm (30 gf / 25 mm).

An object of the present invention is to provide a laminate in which a transfer layer is sandwiched between an object to be transferred and a cover, and to obtain a laminate between a base sheet of the transfer sheet and the transfer layer which is performed in the manufacturing process. Despite being secured, a laminated body having strong adhesion between the transfer layer and the coating can be obtained.

[0009]

Means for Solving the Problems A method for producing a transfer sheet and a laminate according to the present invention employs the following constitution in order to achieve the above object. The invention according to claim 1 is a transfer sheet in which a transfer layer including a release layer and a picture layer is provided on a base sheet via a release layer, wherein the release layer is formed of a resin including an olefin-based resin. The release layer is epoxy resin or /
And a transfer sheet formed of a resin containing a melamine resin. The invention according to claim 2 is the above transfer sheet, wherein the base sheet is a polyethylene terephthalate resin. The invention according to claim 3 is the transfer sheet, wherein the release layer is made of a mixture of an epoxy resin and a melamine resin and is baked. The invention according to claim 4 is the transfer sheet, wherein the release layer further contains an acrylic resin. According to a fifth aspect of the present invention, one end of a 25 mm-wide cellophane adhesive tape (JIS 2152Z) is attached to the base sheet of the transfer sheet after the picture layer side of the transfer sheet is adhered to the transfer object, and the other end is attached. The angle between the support and the cellophane adhesive tape (JIS 2152Z) is always 45
When measuring the weight (peeling weight) of a spring balance when pulling the cellophane adhesive tape (JIS 2152Z) at a speed of 15 mm / sec while maintaining the angle of the degree, the peeling weight between the release layer and the peeling layer was measured. Is 0.001 to 20 × 0.0098 N (g
f) The transfer sheet as described above. According to a sixth aspect of the present invention, an object to be transferred on which a transfer layer transferred from any one of the transfer sheets described above is formed is placed in an injection mold and melted on the transfer layer side of the object to be transferred. This is a method for producing a laminate, which comprises injecting a molding resin for coating to obtain a laminate in which a transferred body / transfer layer / coated body is laminated in this order.
The invention according to claim 7 is the method for producing a laminate, wherein the molding resin for coating is a polypropylene resin.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a transfer sheet 1 in which a release layer 3, a release layer 4, a picture layer 5 and an adhesive layer 6 are sequentially laminated on the surface of a base sheet 2.
FIG. 2 shows a laminate in which the transfer layer 8 is sandwiched between the transfer object 7 and the cover 9.

First, the transfer sheet of the present invention will be described.

Examples of the material of the base sheet 2 include a synthetic resin film such as a polyester resin represented by polyethylene terephthalate, a polypropylene resin, a polyethylene resin, a polyamide resin and a vinyl chloride resin, paper and synthetic paper. The thickness of the base sheet 2 is usually 5 to
200 × 10 ⁻³ mm (5 to 200 μm) is preferable,
More preferably, 12 to 50 × 10 ⁻³ mm (12 to 50 × 10 ⁻³ mm).
μm). The reason is that if it is too thin, the mechanical strength becomes weak, and if it is too thick, the heat in roll transfer or up-down transfer is difficult to be transmitted to the adhesive layer 6, so that the adhesion between the transfer layer 8 and the transferred object 7 becomes weak. This is because, when the temperature of the heat is increased, the transfer operation takes time and labor, and the productivity is reduced. On the surface of the base sheet 2 on which the release layer 3 is formed,
Corona discharge treatment may be performed in order to secure the fixing force with the release layer 3.

The release layer 3 is separated from the release layer 4 during transfer.
It is peeled off and remains on the base sheet 2 side. The release layer 3
Good release properties with olefin resin contained in release layer 4
Including epoxy resin and / or melamine resin
It is formed of resin. The release layer 3 is made of epoxy resin and melamine
It may be a mixture of resin and baked
No. Or, if necessary, wax these resins,
Coating and baking silicone-added resin
May be formed. With the resin forming the release layer 3
Then, 99 weight of melamine resin as resin binder
% To reduce friction when winding the base sheet 2
Contains 1% by weight of wax matting agent for easy winding
There are things. The thickness of the release layer 3 is 0.1 to 0.1 at the time of printing.
10 × 10 ^-3mm (0.1 to 10 μm)
Dry, 0.05-5 × 10^{− 3}mm (0.05
５5 μm). Particularly preferred are the 0.
5-5 × 10^-3mm (0.5 to 5 μm)
It is good to form it. This is too thick and too much heat to dry
This is due to the need for volume and poor work efficiency.
Holes are generated in the release layer 3 and adhere to the base sheet 2
Function and peeling function with the peeling layer 4 are likely to be reduced.
This is because that.

The release layer 4 exerts a release function between the release layer 3 and a close contact function with the cover 9. The release layer 4 is formed of a resin containing an olefin-based resin. As the olefin resin, ethylene resin,
Olefin homopolymer or copolymer such as propylene resin, butene resin, isoprene resin, pentene resin, methylpentene resin, etc., but ethylene-vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin, ionomer Resins, polymer resins of ethylene-propylene-diene and the like. Preferably, a chlorinated polypropylene resin is used. A chlorinated polypropylene resin is a polymer obtained by polymerization of chlorinated propylene, and has a specific gravity of 0.7 to 1.2, a glass transition point of 30 to 110 ° C, and a molecular weight of 30,000 to 300, which are suitable as ink. , And more preferably a glass transition point of 50 to 110 ° C and a molecular weight of 50,
000-200,000. The reason why the transition point in this range is preferable is that the release function between the release layer 3 and
This is because the adhesion function with the coating 9 can be exhibited in a well-balanced manner. The type of olefin resin is
It is good to use properly according to the type of molding resin for coating described later. For example, when a polypropylene resin is used as the coating molding resin, a chlorinated polypropylene resin can be used as the olefin-based resin.

The release layer 4 may further contain an acrylic resin. The reason that the acrylic resin is further included is that the release layer 4 has heat resistance. Examples of the acrylic resin include a polymethyl methacrylate resin and a polymethyl acrylate resin. Specific examples of those further containing an acrylic resin include a mixture of a chlorinated polypropylene resin and an acrylic resin. Release layer 4
Examples of the method include a gravure coating method, a roll coating method, a curtain flow coating method, an air knife coating method, a reverse coating method, a kiss coating method, a blade coating method, a smooth coating method, and a silk screen printing method. The release layer 4 may be formed of two or more layers. The thickness of the release layer 4 is 0.1 to 10 × 10 ⁻³ m during printing.
m (0.1 to 10 μm), and 0.1 mm when dried.
It may be formed to have a thickness of 0.05 to 5 × 10 ⁻³ mm (0.05 to 5 μm). Particularly preferred is 0.5-5 ×
It is about 10 ⁻³ mm (0.5 to 5 μm). The reason for this is that if it is too thick, a large amount of heat is required for drying and the work efficiency is reduced, and if it is too thin, there is a high possibility that pinholes or the like will occur and the function of peeling off from the release layer 3 will be reduced. is there.

The following values are preferable as the peeling weight between the release layer 4 and the release layer 3. After the adhesive layer 6 of the transfer sheet 1 is adhered to the transfer object 7, a 25 mm-wide cellophane adhesive tape (JI) is applied to the base sheet 2 of the transfer sheet 1.
S 2152Z), one end of which is adhered and the other end is supported by a spring scale, and a support base and a cellophane adhesive tape (JIS 215
2Z) and a cellophane adhesive tape (JI) at a speed of 15 mm / sec.
S 2152Z), when the weight (peeling weight) of the spring scale when pulling was measured, the peeling weight between the release layer 3 and the peeling layer 4 was 0.001 to 20 × 0.0098N (0.001 to 20
gf). 0.001 × 0.0098N (0.00
If it is less than 1 gf), foil spillage (a phenomenon of peeling between the release layer 3 and the release layer 4 in an unnecessary scene such as a winding operation of a transfer sheet) tends to occur, which is inconvenient.
If it exceeds 20 × 0.0098 N (20 gf), the phenomenon that the transfer layer 8 does not completely transfer to the transfer object 7 during transfer and a part of the transfer layer remains in the release layer tends to occur. In a combination using a melamine resin as the release layer 3 and an olefin-based resin as the release layer 4, 0.5 to 3 × 0.00
98N (0.5-3 gf) is most preferred. The transfer conditions for measuring the peeling weight include, for example, a pressing force of 14.7 N / cm 2 by a silicone rubber roller.
(1.5 kgf / square cm), heating temperature of 220 ° C. by a silicon rubber roller, peeling speed of the base sheet 3 m /
There is a condition of min.

The picture layer 5 is a layer for giving a picture to the transfer object 7. The picture layer 5 exhibits a pattern, a picture, or a solid color pattern uniformly formed by using an ink in which a pigment, a dye, or the like is added to a resin binder. As the material of the picture layer 5, a colored ink containing a resin such as a polyvinyl-based resin, a polyamide-based resin, or a polyester-based resin as a binder and a pigment or dye of an appropriate color such as titanium oxide or carbon black as a coloring agent is used. Good. The picture layer 5 may be composed of a metal thin film layer or a combination of a printing layer and a metal thin film layer. Examples of the metal thin film layer include a vacuum deposition layer using aluminum. As a method of forming the picture layer 5, there is a coating method similar to that of the release layer 4. The picture layer 5
Two or more layers such as a first pattern layer and a second pattern layer may be formed. The thickness of the picture layer 5 is 1.5 to 4 at the time of printing.
It may be formed so as to be in a range of 0 × 10 ⁻³ mm (1.5 to 40 μm) and 1 to 20 × 10 ⁻³ mm (1 to 20 μm) when dried.

The adhesive layer 6 is a layer of the layer constituting the transfer layer 8 which is in direct contact with the transferred body 7 and is temporarily melted by heating during roll transfer or up-down transfer and adheres to the transferred body 7. It is. The adhesive layer 6 can be omitted when there is an adhesive property between the transfer layer 8 of the transfer sheet and the transfer object 7. Further, the adhesive layer 6 may be formed on the transfer object 7 when manufacturing the laminate. As a method for forming the adhesive layer 6, there is a coating method similar to that for the release layer 4, and the like. Picture layer 5
May be formed in two or more layers such as a first adhesive layer and a second adhesive layer. The thickness of the picture layer 5 is 1 to 1 at the time of printing.
It is preferable that the film is formed to have a range of 0 × 10 ⁻³ mm (1 to 10 μm) and a range of 0.5 to 5 × 10 ⁻³ mm (0.5 to 5 μm) when dried.

The method for producing the laminate of the present invention will be described.

The transferred object 7 on which the transfer layer 8 transferred from the transfer sheet is formed is placed in an injection molding die, and the molten molding resin is injected onto the transfer layer 8 side of the transferred object 7. Thus, a laminated body is obtained in which the transferred body 7 / transfer layer 8 / coated body 9 are laminated in this order. Specifically, first, the transfer target body 7 on which the transfer layer 8 is formed is fed into an injection molding die including a movable die and a fixed die. The transfer target 7 is placed at a position where the coating molding resin covers the release layer 4 of the transfer layer 8. After closing the injection molding die, the molding resin for coating is injected and filled into the cavity from the gate provided on the fixed die, and the release layer 4 of the transfer layer 8 is covered with the resin for coating. After the laminated body laminated in the order of the transferred body 7 / transfer layer 8 / coated body 9 is cooled, the injection molding die is opened and the laminated body is taken out. Examples of the molding resin for coating include polyethylene resin and polypropylene resin. Particularly, a polypropylene resin is preferable. The reason is that the adhesion to the olefin resin as the release layer 4 becomes particularly good.

[0021]

EXAMPLES A biaxially stretched polyethylene terephthalate film having a thickness of 25 μm was used as a base sheet, and a release layer, a release layer,
A transfer sheet in which a picture layer and an adhesive layer were sequentially arranged was obtained. The release layer is formed by applying an ink composed of the following composition onto a base sheet by a reverse coating method, and baking at a temperature of 200 ° C.
It was formed by performing a printing process at a line speed of 5 m / min. The coating film thickness is about 5 × 10 ⁻³ mm when dried.
(5 μm). The release layer was formed by applying an ink having the following composition onto the release layer by a gravure coating method, and performing a drying treatment at a drying temperature of 80 ° C. and a line speed of 30 m / min. The coating thickness of the release layer was set to be about 1 × 10 ⁻³ mm (1 μm) when dried. The picture layer was formed by using the ink having the following composition in the same manner as the release layer. The coating thickness of the picture layer is 3 × 10
^-3 mm (3 μm). The adhesive layer
An ink having the following composition was obtained in the same manner as the release layer.
The coating thickness of the adhesive layer was 1 × 10 ⁻³ mm (1 μm) when dried.
m).

[Ink composition of release layer] Melamine resin as a resin binder is 99% by weight, and a wax matting agent made of silica is 1% by weight.

[Ink composition of release layer] The chlorinated polypropylene resin is composed of 80% by weight and the polymethyl methacrylate resin is composed of 20% by weight.

[Picture layer ink composition] An acrylic resin is 60% by weight and a vinyl resin is 40% by weight.

[Adhesive Layer Ink Composition] A chlorinated polypropylene resin as a resin binder is 95% by weight, and a silica wax matting agent is 5% by weight.

Using the transfer sheet thus obtained, a pressing force of 14.7 N / cm 2 by a silicone rubber roller is applied to a transfer object made of polypropylene resin.
(1.5 kgf / square cm), heating temperature of 220 ° C. by a silicon rubber roller, peeling speed of the base sheet 3 m /
The transfer process was performed under the conditions of min to obtain a transfer-receiving body on which a transfer layer was formed. Release weight between release layer and release layer is 0.2
× 0.0098 N (0.2 gf), which was an ideal value. The peeling weight was measured by using a 25 mm-width cellophane adhesive tape (JI) on a base sheet of a transfer sheet adhered to an object to be transferred.
S 2152Z), one end of which is adhered and the other end is supported by a spring scale, and a support base and a cellophane adhesive tape (JIS 2152) are attached.
Z) always keeps an angle of 45 degrees and 1
Cellophane adhesive tape (JIS 21) at a speed of 5 mm / sec.
52Z) The weight (peeling weight) of the spring scale when pulling was measured.

Next, the object to be transferred is fed into an injection molding die, and the object to be transferred is placed at a position where the molding resin for coating covers the release layer of the transfer layer. I got Even if the molded article was subjected to a heat resistance test in which the molded article was left for 5 minutes in an environment of 100 ° C., no void was found at the interface between the release layer and the molding resin for coating. More specifically, the heat resistance test involves immersing the molded article in water, heating the molded article in a microwave oven for 5 minutes, and boiling the water.

[0028]

Since the transfer sheet of the present invention has the above-described structure, when obtaining a laminate in which the transfer layer is sandwiched between the transfer object and the cover, the adhesion between the transfer layer and the cover is improved. It is strong and has good releasability between the base sheet and the transfer layer.

In the method for producing a laminate according to the present invention, the above-described structure provides good releasability between the base sheet and the transfer layer, so that even when a laminate having strong adhesion between the transfer layer and the cover is obtained. , And productivity is improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a transfer sheet of the present invention.

FIG. 2 is a cross-sectional view showing a laminate of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transfer sheet 2 Substrate sheet 3 Release layer 4 Release layer 5 Picture layer 6 Adhesive layer 7 Transfer object 8 Transfer layer 9 Coating

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B44C 3/02 B44C 3/02 Z // B29K 23:00 B29K 23:00 F-term (Reference) 3B005 EA01 EB01 EC21 FA04 FB01 FB21 FC01X FC08X FD10X FE04 FE22 FG04X FG06Y FG07Y GA02 GB01 GD10 4F100 AA20E AA20H AK03C AK07E AK10C AK10E AK21D AK25C AK25D AK36B AK42A AK53B AL05B AL05C AL05D AR00D AR00E AT00A BA10A BA10E CA23E EC042 EH362 EH461 GB90 HB00D JK06 JL11E JL14C YY00 4F206 AA11 AD05 AD10 AD20 AE10 AG03 AH33 AH51 AH55 AH56 JA07 JB19 JL02

Claims (7)

[Claims] 1. A transfer sheet in which a transfer layer including a release layer and a picture layer is provided on a base sheet via a release layer, wherein the release layer is formed of a resin containing an olefin-based resin. Is formed of a resin containing an epoxy resin and / or a melamine resin. 2. The transfer sheet according to claim 1, wherein the base sheet is a polyethylene terephthalate resin. 3. The transfer sheet according to claim 1, wherein the release layer is made of a mixture of an epoxy resin and a melamine resin and is baked. 4. The transfer sheet according to claim 1, wherein the release layer further contains an acrylic resin. 5. After the picture layer side of the transfer sheet is adhered to the transfer object, one end of a 25 mm wide cellophane adhesive tape (JIS 2152Z) is attached to the base sheet of the transfer sheet, and the other end is supported by a spring balance. Then, the angle between the support and the cellophane adhesive tape (JIS 2152Z) always keeps an angle of 45 degrees, and the weight of the spring scale when pulling the cellophane adhesive tape (JIS 2152Z) at a speed of 15 mm / sec ( When the release weight was measured, the release weight between the release layer and the release layer was 0.001 to 20 × 0.0098 N (gf).
The transfer sheet according to any one of claims 1 to 4, wherein 6. A transfer object formed with a transfer layer transferred from the transfer sheet according to any one of claims 1 to 5, is placed in an injection mold, and is melted on the transfer layer side of the transfer object. A method of manufacturing a laminate, comprising: injecting the formed molding resin to obtain a laminate in which a transfer target / transfer layer / coating is laminated in this order. 7. The method for producing a laminate according to claim 6, wherein the molding resin for coating is a polypropylene resin.