JPH02160556A - Transfer of pictorial pattern to compact disk and transfer sheet - Google Patents

Abstract

PURPOSE:To make possible transfer of a beautiful and stable pictorial pattern by laminating a peel-off material layer, a pictorial pattern printing layer and an adhesive layer sequentially on a heat-resistant basic material film. CONSTITUTION:Peel-off material layers 2A, 2B which move over a material to be transferred on and become the surface of a pictorial pattern 6 after transfer, a pictorial pattern printing layer 3 and an adhesive layer 4 at a softening temperature of 50 to 65 deg.C are sequentially laminated on a heat-resistant basic material film 1. In this case, if the peel-off layer 2A is formed using an ultraviolet curing-type or an electronic beam curing-type resin and then is allowed to cure, a pictorial pattern becomes more durable. A preferable adhesive is a copolymer of 15 to 40% by weight of styrene and 60 to 85% by weight of lower alkylester (meta) acrylate at a glass transition point of 50 to 95 deg.C and with an average molecular weight by weight/average molecular weight by number = 2 to 5 and an average molecular weight by weight of 10,000 to 25,000. The application amount of the adhesive is 1 to 12g/m<2>, preferably 2 to 7g/m<2>. A pictorial pattern is transferred to a part where data can be read without causing any hazard of the surface of a compact disk, using hot stamp technique at 160 deg.C or less with a transfer sheet of the above structure.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for transferring decoration onto compact discs, and also includes a transfer sheet used for carrying out the method.

[Conventional technology]

Needless to say, the label of a compact disc (hereinafter abbreviated as rcDJ) is attached to the central part where no information is recorded, but information can only be read from one side of the CD, and the other side is unrelated. Because there is, you can set a pattern here. The conventional method is to attach a label with a pattern printed on a paper material such as art paper using an adhesive. These labels are thick, have uneven edges, and are susceptible to peeling and abrasion. Also, while the surface of a CD has a unique shine,
Paper labels do not have this and are opaque, which actually detracts from the beauty inherent to CDs. Therefore, attempts were made to stop using paper labels and print designs directly onto CDs using screen printing or offset printing. In reality, screen printing mainly produces monochromatic patterns. This is because overprinting is necessary to create a pattern of two or more colors, which is not very productive. It is also difficult to create photographic patterns. Offset printing cannot produce textured patterns, and it is difficult to match the printing register on CDs, making multicolor printing difficult. Regardless of the printing method, since the CD as the printing medium is expensive, there is a large loss when printing fails. For this reason, the technology for directly inserting images onto CDs is
It has not yet reached a practical level.

[Problem to be solved by the invention]

An object of the present invention is to solve the above-mentioned problems using transfer printing technology, and to provide a more beautiful and durable painting method than simply pasting a label, and a transfer sheet used for carrying out the method. (Means for Solving the Problems) As shown in FIG. 1, the CD transfer sheet of the present invention has one or more layers on a heat-resistant base film (1). On the transfer body (release material layer (2 layers 2A and 2B in the figure) that transfers and becomes the surface of the pattern, pattern printing layer (3),
and an adhesive layer (4) having a softening temperature of 50 to 65° C. are laminated in this order. The heat-resistant base film is preferably a polyethylene film, a nylon film, or a polyester film with a thickness of 12 to 100 μm, and a polyester film with a thickness of 15 to 50 μm is particularly preferred. In order to improve the releasability of the release material layer during transfer, a release layer that remains on the base film after transfer may be formed on the base film. For this release layer, a known ink vehicle to which a release material such as wax, silicone, or fluororesin is optionally added can be used. The release material layer is made of (meth)acrylic acid resin, copolymer of styrene and (meth)acrylic acid lower alkyl ester, vinyl chloride-vinyl acetate copolymer, chlorinated rubber, cyclized rubber, nitrocellulose or cellulose acetate butyrate, etc. Formed from a known material. A small amount of silicone wax agent or the like may be added to these. A release material layer (2A) that will become the surface of the pattern (6) after transfer is formed from an ultraviolet curable or electron beam curable resin,
When cured, it acts as a protective layer and can improve the durability of the design. As the electron beam curable resin, oligomers such as epoxy acrylate, urethane acrylate, or acrylic modified polyester are used, and in order to adjust the crosslinked structure and viscosity, etc., seven polymers such as neopentyl glycol acrylate and trimethylolpropane triacrylate are added.
Examples include those containing the following. If it is necessary to adjust the viscosity without changing the crosslink density of the cured product, use ethyl acetate,
It is best to dilute with a commonly used organic solvent such as methyl ethyl ketone or toluene. As the ultraviolet curable resin, the above-mentioned resin mixed with a photopolymerization initiator is used. The release material layer may be provided by gravure coating, roll coating, screen printing, offset printing, etc., and the coating amount is 0.5 to 10 g/TIt, preferably 0.7 to 2
g/Td. The pattern printing layer may be formed using known inks and printing methods. The adhesive used in the transfer sheet of the present invention has a softening temperature of 5.
It is a heat-sensitive adhesive with a temperature range of 0 to 65°C. Such adhesives are selected from among acrylic resin, vinyl acetate resin, rubber resin, polystyrene, polyolefin, epoxy resin, vinyl chloride-vinyl acetate copolymer, diallyl phthalate resin, and mixtures thereof, and have a softening temperature within the above range. Choose what fits in and use it. A particularly preferred adhesive is a copolymer consisting of 15 to 40% by weight of styrene and 60 to 85% by weight of lower alkyl (meth)acrylate, and has a glass transition point of 50=9.
5°C, weight average molecular weight/number average molecular weight = 2 to 5, weight average molecular weight ff1lo, 000 to 25,000. The adhesive layer may be formed by a known method such as gravure coating, roll coating, screen printing or offset printing, and the coating amount is 1 to 12 g/bottom, preferably 2 to 7 g.
g/m. Of course, for perfect transfer, the adhesive layer must not be smaller than the diameter of the CD. - On the other hand, in order to prevent the generation of flakes on the release layer, pattern printing layer, and adhesive layer during transfer, the adhesive layer should be shaped into a circle with a diameter slightly larger than the diameter of the CD, typically 3 or less. It is preferable to form. The transfer painting method for a CD of the present invention uses the above-mentioned transfer sheet on a part of the CD that does not interfere with the reading of information.
It consists of hot stamping at a temperature below 0°C to transfer the design. The parts where there is no problem in reading information are:
In addition to the center of the front of a CD, this is also the back of a regular CD. The CD (7) shown in FIG. 2 has a pattern (6) formed by painting on both sides. In Figure 3, which shows the details, the layer on the surface of the pattern (2
C) is cured to form a protective layer. Effect] It is known to apply pictures to plastic molded products by thermal transfer, but the use of transfer sheets requires heating temperatures of nearly 200°C. CDs are generally made of polycarbonate or acrylic resin molded products with metal vapor-deposited, and are sensitive to heat, so there is a risk of deformation if subjected to such high temperatures. They are often coated with ultraviolet curable resin to protect the surface, and sufficient adhesive strength cannot be obtained unless the heat transfer temperature is raised. For this reason, it was considered impractical to add pictures to CDs using the thermal transfer method. However, the inventors believe that there is no limit to the ink or printing method;
As a result of our research, we aimed to take advantage of the transfer method's ability to easily form a desired pattern with photographic gradation and gloss, and in a thin film. The maximum temperature at which stamping can be done is approximately 16
0℃, and even at this temperature, the softening temperature of the heat-sensitive adhesive must be 5.
The present invention was achieved by discovering that a temperature within the range of 0 to 65°C should be used. When a heat-sensitive adhesive having a softening temperature higher than 65° C. is used in a transfer sheet, it will not melt sufficiently at a hot stamping temperature of 160° C. or lower, resulting in weak adhesive strength. On the other hand, heat-sensitive adhesives with a low softening temperature below 50°C
Depending on the storage conditions of D, the adhesive strength may decrease and the pattern may shift, so it is not practical. [Example 1] Polyester film "Lumirror S-'I" with a thickness of 25μ
Apply the first release material layer made of polyurethane in an amount of 0.7 g/bottom to OJ (east side) on top of it f! 1.0g
A second release material layer consisting of a mixture of polyurethane and nitrocellulose in an amount of 1/2/m was provided by gravure coating. A pattern is gravure printed on the second release material layer using ink with an acrylic resin vehicle, and then a heat-sensitive adhesive (
A transfer sheet having the structure shown in FIG. 1 was obtained by silk screen printing at a coating amount of 39/TIi (softening temperature: 60° C.). Align the center of the image on this transfer sheet with the center of the CD,
Hot stamping was performed at 160°C, and the base material was peeled off. The resulting CD had a pattern that adhered well and was not deformed. [Example 2] A first release material consisting of 25 parts by weight of urethane acrylate, 25 parts by weight of trimethylpropanol, 50 parts of methyl methacrylate, and 2 parts of t-butylanthraquinone (photoradical initiator) was added to the same polyester film as used in Example 1. was applied in an amount of 1.09/riI and cured by irradiation with ultraviolet rays. On top of that, a second release material made of polyurethane resin is applied.
59/rd was applied. A pattern was then printed using an ultraviolet curable offset ink with the following composition and cured with ultraviolet light. Epoxy acrylate 20% by weight aluminum
5 Photoinitiator
7 Wax 15 Pigment 52 Styrene 3
A copolymer consisting of 0.4% by weight and 70% by weight of an acrylic ester/methacrylic ester mixture, with a glass transition point of 90°C, a weight average molecular weight/number average molecular weight of 3, and a weight average molecular weight of 19° OOO. Used as adhesive, CD
1.0g/ in a circle with a radius 2s larger than the radius of
rd to obtain a transfer sheet having the structure shown in FIG. Transfer was performed on this transfer sheet in the same manner as in Example 1.
No flaking occurred when the base film was peeled off, and the resulting decorated CD had good adhesion of the pattern and was not deformed. [Effects of the Invention] According to the CD decorating method of the present invention, a CD with a more beautiful design than a CD with a conventional paper label or one directly printed can be obtained. The pattern layer is thin and the edges are not noticeable, so you don't have to worry about the difference in level. The adhesion between the pattern and the CD is strong enough that the pattern will not shift or peel off. In particular, those with a hardened resin layer on the surface have high durability. By using the transfer sheet of the present invention, there is no need to worry about deformation, and there is almost no chance of producing defective products during the painting process.
It is possible to produce illustrated CDs. The present invention is applicable to LD (laser disc) and CDV (CD with video).
), etc. It goes without saying that it can be applied to other optical AV discs based on the same principle, and rcDJ is an edict that includes them.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing a typical example of the transfer sheet of the present invention. Figure 2 shows C painted using the transfer sheet of the present invention.
It is a sectional view of D. FIG. 3 is an enlarged view of the circle in FIG. 2. 1...Base film 2A, 2B...Release material layer 3...Picture printing layer 4...Adhesive layer 6...Picture 7...CD Patent applicant Agent for Dai Nippon Printing Co., Ltd. People Patent Attorney Souo Suga

Claims (6)

[Claims] (1) On a heat-resistant base film, there is one or more layers, including a release material layer and a pattern printing layer, which will be transferred onto the transfer target and become the surface of the pattern after transfer, and a softening temperature of 50 or more. A transfer sheet for compact discs made by sequentially laminating adhesive layers at 65°C. (2) The transfer sheet according to claim 1, wherein an ultraviolet curable or electron beam curable resin is used in the release material layer that forms the surface of the pattern after transfer. (3) As an adhesive, 15 to 40% by weight of styrene and 60 to 85% by weight of lower alkyl (meth)acrylic acid ester
A copolymer consisting of a glass transition point of 50 to 95°C
, weight average molecular weight/number average molecular weight=2 to 5, weight average molecular weight 10,000 to 25,000, and the coating amount of the adhesive layer is 1 g/m^2 or more. Transfer sheet as described. (4) Place the adhesive layer 3mm from the diameter of the compact disc.
The transfer sheet according to any one of claims 1 to 3, wherein the transfer sheet is formed into a circular shape having a diameter larger than or equal to the following. (5) Using the transfer sheet according to claim 1 on a portion of the surface of the compact disc where there is no problem in reading information;
A method for transferring pictures onto compact discs, which involves transferring designs by hot stamping at a temperature of 60°C or less. (6) The method for transferring and decorating a compact disc according to claim 5, which comprises using the transfer sheet according to claim 2 and curing the surface by irradiating ultraviolet rays or electron beams after hot stamping.