JP3395450B2 - Binder resin for primer for hydraulic transfer sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic transfer sheet used for forming a printed pattern on the surface of a molded product by a hydraulic transfer method. More specifically, the printed pattern layer formed on the hydraulic transfer sheet is hydraulically pressed. The present invention relates to a binder resin for a primer which is applied onto the printed pattern layer at the time of transfer, and particularly to a primer for a hydraulic transfer sheet capable of forming a printed pattern layer having excellent adhesiveness on the surface of a polyolefin molded article. It relates to a binder resin.

[0002]

2. Description of the Related Art In a hydraulic transfer system, a printed pattern layer of a water-soluble or water-swellable film having a printed pattern layer on its surface is dissolved or swollen into a fluidized state on the printed pattern layer. Apply a coatable primer (sometimes referred to as an activator), and then float this hydraulic transfer sheet on water with the printed pattern layer side facing upwards so that the fluidized printed pattern layer is on the water surface. At the stage of spreading to the
This is a method of transferring a printed pattern layer, which is in a fluid state and extended, onto the surface of a molded article by hydraulic pressure. For the hydraulic transfer method, see, for example, JP-A-61-58798.
It is already known from Japanese Patent Publication No. 2-32160.

The primer used in the above-mentioned hydraulic transfer system is an organic solvent capable of dissolving (or swelling) the printed pattern layer formed on the hydraulic transfer sheet, and a viscosity adjustment for efficiently advancing the transfer process. An essential component is a binder resin that allows the printed pattern layer after transfer to adhere well to the surface of the transferred material, and further improves the spread of the printed pattern layer fluidized by applying a primer on the water surface if necessary. In general, a plasticizer for controlling the viscosity, an extender pigment for preventing the coating pattern of the printed pattern layer from cracking in the drying step after transfer, and the like are blended.

By the way, the primer used in the above-mentioned conventional hydraulic transfer sheet has a surface of the molded product when the molded product is made of a non-polyolefin plastic such as ABS, polycarbonate resin, vinyl chloride resin, acrylic resin or the like. It is possible to form an adhesive print pattern layer that is practically satisfactory for, but when the material of the molded product is a polyolefin resin such as polyethylene or polypropylene,
There is a problem that the transferred printed pattern layer has extremely low adhesion and cannot be put to practical use.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have found the problems in the above-mentioned conventional hydraulic transfer primers, namely,
As a result of further studies to solve the problem that it is difficult to form a printed pattern with excellent adhesiveness on the surface of a polyolefin resin molded product, it is said that it exhibits good adhesion to a polyolefin substrate. It was found that when a chlorinated polyolefin is used as a binder resin for the above-mentioned primer, the adhesiveness of the printed pattern layer can be greatly improved.However, since the chlorinated polyolefin is generally hydrophobic, it has a hydrophilic organic property. It is difficult to dissolve in a solvent, and therefore the solvent composition of the primer using the chlorinated polyolefin resin as a binder is inevitably composed of a hydrophobic organic solvent, and the primer composed of such a hydrophobic organic solvent. Is a drawback that when the hydraulic transfer sheet is floated on the water surface, the printed pattern layer formed on the sheet is difficult to spread uniformly and satisfactorily on the water surface. There, it has been found that a new problem that blurred transfer pattern collapses of the printed pattern layer give only.

Therefore, in view of the above situation, the present invention is capable of forming a printed pattern layer having excellent adhesion to a polyolefin resin molded article and at the same time the printed pattern layer when floated on the water surface. As a result of further study to obtain a hydraulic transfer primer that has good spreadability and is capable of forming a clear printed pattern, a graft copolymer obtained by graft-polymerizing a specific hydrophilic acrylic monomer on a chlorinated polyolefin resin. When used as a binder for a hydraulic transfer primer, the printed pattern layer can be uniformly and sufficiently extended on the water surface even when the organic solvent composition is composed of a hydrophobic organic solvent, and the polyolefin resin molding can be performed. The inventors have found that it can be a primer that exhibits excellent adhesion to products.

[0007]

The binder resin of the primer for a hydraulic transfer sheet provided by the present invention comprises a water-soluble or water-swellable film having a printed pattern layer formed thereon to form the printed pattern layer. Dissolves (or swells) the printed pattern layer by applying to the surface
A binder for use in a primer that can be used, wherein the binder of the primer is 5 to 50% by weight of alkoxy. (Poly) alkylene glycol mono (meth) acrylate and 5 to 50% by weight of chlorinated polypropylene resin.
50% by weight and polymerizable unsaturated group-containing vinyl compound 0 to
It is characterized by being a graft copolymer composed of 90% by weight.

In the present invention having the above constitution, as the binder resin, chlorinated polypropylene resin is added to alkoxy. (Poly) alkylene glycol mono (meth).
A major feature is that it is composed of a copolymer obtained by graft-polymerizing acrylate, and since the alkoxy / (poly) alkylene glycol / mono (meth) acrylate used here is hydrophilic, it is chlorinated polypropylene resin by grafting. Can be made hydrophilic, and the spreadability of the printed pattern layer on the water surface is not impaired even when the organic solvent composition of the primer is a hydrophobic solvent.

Specific examples of the alkoxy (poly) alkylene glycol mono (meth) acrylate which can be used to obtain the binder resin of the present invention include 2-
Methoxyethyl methacrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, methoxydiethylene glycol acrylate, methoxytriethylene glycol acrylate, methoxytetraethylene glycol acrylate, methoxydipropylene glycol acrylate, ethoxydiethylene glycol acrylate, etc., and NOF Corporation. The brand name Blemmer PME-100, the same PME-200, the same PME-400, etc. are mentioned, and these can be used individually or in mixture of 2 or more types.

Among the above-mentioned alkoxy. (Poly) alkylene glycol mono (meth) acrylates, alkoxy. (Poly) ethylene glycol monomethacrylate is derived from the hydrophilicity / hydrophobicity of the side chain group on the water surface of the printed pattern layer. Since it is excellent in both the spreadability and the stability of the primer itself due to the compatibility with chlorinated polypropylene, in the present invention, alkoxy polyethylene glycol monomethacrylate, specifically, methoxydiethylene glycol acrylate, It is particularly preferable to use methoxytriethylene glycol acrylate, methoxytetraethylene glycol acrylate, ethoxydiethylene glycol acrylate, etc., and Bremmer PME-200 under the trade name of NOF CORPORATION.

The chlorinated polyolefin resin which can be used in the present invention is not particularly limited and can be appropriately selected and used from those having various chlorination rates. However, when the chlorination rate of the chlorinated polyolefin resin is lower than 15%, the solubility in an organic solvent and the storage stability when used as a primer are lowered, and when the chlorination rate is higher than 50%, a polyolefin-based resin is used. In the present invention, it is preferable to use a chlorinated polyolefin resin having a chlorination ratio in the range of 15 to 50% because the adhesion to the substrate tends to decrease.

The polymerizable unsaturated group-containing vinyl compound that can be used in the present invention is not particularly limited, and any compound having a polymerizable unsaturated bond can be used. Specific examples include styrene, α-methylstyrene, vinyltoluene, (meth) acrylic acid, hydroxyethyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, amyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic acid Examples thereof include isobornyl, vinyl chloride, vinyl acetate, dimethyl fumarate, diethyl fumarate, vinyl propionate, dimethyl itaconate and diethyl itaconate, and these can be used alone or in combination of two or more. Among these vinyl compounds, methyl (meth) acrylate, ethyl (meth) acrylate,
(Meth) acrylic acid-n-butyl, (meth) acrylic acid-iso-butyl, (meth) acrylic acid-tert-butyl, (meth) acrylic acid hexyl, (meth) acrylic acid-2-ethylhexyl, (meth) Acrylic acid-n-lauryl, cyclohexyl (meth) acrylate, (meth)
Preference is given to using isobornyl acrylate.

In the present invention, the graft copolymer suitable as the binder resin contains 5 to 50 of the above alkoxy polyalkylene glycol mono (meth) acrylate.
% By weight, 5 to 50% by weight of chlorinated polyolefin resin,
A polymerizable unsaturated group-containing vinyl compound is graft-polymerized in the range of 0 to 90% by weight, and the graft copolymer has less than 5% by weight of alkoxy polyalkylene glycol mono (meth) acrylate. And, since the hydrophilicity of the obtained binder resin is lowered, the spreadability of the printed pattern layer on the water surface is impaired,
If it is more than 50% by weight, the hydrophilicity becomes remarkably large, so that the adhesion to the polyolefin-based substrate is impaired and the storage stability when used as a primer is deteriorated. Further, if the amount of chlorinated polypropylene resin is less than 5% by weight, the adhesion to the polyolefin-based substrate will be reduced, and if it is more than 50% by weight, the hydrophobicity of the binder resin will be strengthened, so that the spreadability of the printed pattern layer on the water surface will increase. It will be damaged. When the amount of the polymerizable unsaturated group-containing vinyl compound is more than 90% by weight, both the adhesiveness to the polyolefin-based substrate and the spreadability of the printed pattern layer on the water surface are impaired.

The above graft copolymer is generally prepared by adding a predetermined amount of an alkoxy polyalkylene glycol mono (meth) acrylate and a polymerizable unsaturated group-containing vinyl compound to a chlorinated polypropylene resin in an organic solvent solution. In addition, it can be produced by a known polymerization method in the presence of an appropriate polymerization initiator. As an example, 70 to 10
It is preferable to carry out solution polymerization at 0 ° C. In this case, as a polymerization solvent, an aromatic hydrocarbon such as toluene or xylene is mainly used, and if necessary, cyclohexane, methylcyclohexane, methyl isobutyl ketone, butyl acetate or the like is used in combination. You can Further, as the polymerization initiator used at that time, benzoyl peroxide, organic oxide such as t-butyloxy-2-ethylhexanoate, azobisisobutyronitrile, dimethyl-2,2 ′
Examples include azo compounds such as azobisisobutyrate.

The binder resin thus obtained can be used as a primer for hydraulic transfer by mixing it with an appropriate organic solvent. As the organic solvent that can be used here, any organic solvent can be used as long as it can dissolve the above-mentioned graft copolymer and at the same time can dissolve (or swell) the printed pattern layer formed on the hydraulic transfer sheet. You don't have to. Specific examples of the organic solvent that can be used, pentane, hexane, heptane, octane, mineral spirits, toluene, xylene, cyclohexane, ethylbenzene, tetralin, decalin, methyl alcohol, ethyl alcohol,
Propyl alcohol, butyl alcohol, amyl alcohol, benzyl alcohol, diacetone alcohol, ethylene glycol, propylene glycol, glycerin, methyl acetate, ethyl acetate, butyl acetate, acetone,
Methyl ethyl ton, methyl isobutyl ketone, cyclohexanone, isophorone, ethyl ether, isopropyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, ethylene glycol monomethyl ether Ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether Seteto, and Idemitsu Kosan Co., Ltd. of super sol series (trade name) and the like, these can be used by mixing one or two or more kinds.

The organic solvent must be kept at a viscosity suitable for transfer at least until the print pattern layer on the hydraulic transfer sheet is in a fluid state and transferred to the transfer step, and printing after transfer is performed. In the step of drying the pattern layer, it is desirable that the organic solvent to be used is well exposed to the solvent and easily dried, so that the boiling point range of the organic solvent used is preferably 50 to 300 ° C. ~ 3
0 wt% preferably contains a high boiling point solvent of 200 to 300 ° C.

There is no particular limitation in producing a primer for a hydraulic transfer sheet using the binder resin of the present invention. Generally, the above graft copolymer and the organic solvent are added in an amount of 5 to 50% by weight of the graft copolymer and 5% by weight of the organic solvent.
It is obtained by mixing in the range of 0 to 95% by weight.

The primer obtained by the above composition is
Although it can be used as it is as a primer for dissolving the printed pattern layer of the hydraulic transfer sheet, it is preferable to further add inorganic fibers and a plasticizer to the primer, if necessary. The inorganic fibers are useful for preventing the occurrence of coating film cracks when the printed pattern transferred to the surface of the molded article is dried, and the plasticizer has the effect of improving the spreadability of the printed pattern layer on the water surface.

The inorganic fiber in the primer is preferably used in the range of 5 to 30 parts by weight with respect to 100 parts by weight of the binder resin, and the plasticizer is preferably used in the range of 20 to 100 parts by weight. The inorganic fiber that can be used is not particularly limited, and generally, the fiber diameter is preferably 0.5 to 1.0 μm, and the fiber length is preferably 10 to 30 μm. Specific examples thereof include Shikoku. Examples include the product names Arbolex YS series and M series manufactured by Kasei Kogyo Co., Ltd. In addition, specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, dioctyl adipate, dioctyl sebacate, epoxy plasticizers, trimellitic acid plasticizers, polyester plasticizers and the like.

Further, for the primer, a resin (for example, an organic solvent-soluble thermosetting acrylic resin or a thermoplastic acrylic resin) other than the above graft copolymer, a pigment (for example, talc, mica, carbonic acid) is used. Calcium, clay, barite, etc.) and various other additives known in paint applications (eg dispersants, defoamers,
It is acceptable to add a surfactant or the like) within a range that does not impair the characteristics of the hydraulic transfer primer.

The primer containing the binder resin of the present invention can be used in exactly the same manner as the primer used in the conventional hydraulic transfer system. As an example, the primer according to the present invention is brushed on the printed pattern forming surface of a water pressure transfer sheet of a water-soluble or water-swellable film (starch-based film, polyvinyl alcohol-based resin film, etc.) having a water-insoluble printed pattern layer. Coating, spray coating, roll coating, curtain flow coating, gravure coating, or any other known coating method to obtain a wet coating thickness of 10 to 10.
It is applied so as to have a thickness of about 30 μm, and when the printed pattern layer is in a fluidized state, this hydraulic transfer sheet is floated on the water surface so that the printed pattern forming layer on the sheet is the upper surface. When the molded product is pushed up into the water from above, the printed pattern is transferred to the surface of the molded product. Thus, the molded product after transfer is removed from water, the water-soluble sheet residue remaining on the printed pattern layer is washed off with water, dried and, if necessary, a top coat for protection is further applied to the surface. A molded article decorated with the surface printed pattern layer is obtained.

[0022]

EXAMPLES The present invention will be specifically described below based on examples. The copolymerization ratios or mixing ratios of the respective components in the examples are shown in parts by weight unless otherwise specified.

Example 1 [Production of Binder Resin] A 1-liter four-necked flask equipped with a stirrer, a cooler and a monomer dropping device was placed in Table 1 below.
Each component of the composition (A) shown in was charged, heated under stirring until the internal temperature reached 90 ° C., and further held at 90 ° C. for 20 minutes. Then, the monomer mixture of the composition (B) is added dropwise for one and a half hours, and after the completion of the addition, the components of the composition (C) are added,
Polymerization was completed by holding at 90 ° C for 3 hours. Then, the copolymer solution was diluted with toluene as a diluent to obtain binder resin solutions V1 to V5, W1 and W2.

[0024]

[Table 1]

[Production of Primer] Using each of the binder resin solutions (V1 to V5, W1 and W2) obtained above, the components were uniformly mixed in the composition shown in Table 2 below to prepare a primer for a hydraulic transfer sheet. Manufactured.

[Evaluation of Performance of Primer] The primer obtained above was applied to a hydraulic transfer sheet (P
VA film) on the printed pattern layer by a gravure coating method so as to have a wet film thickness of 15 μm, and this sheet is floated on the water surface at a water temperature of 30 ° C. with the printed pattern layer as the upper surface. Push in the resin molded product, and hydraulically transfer the printed pattern layer on the water surface to the molded product surface,
Then, it was washed with water and then dried at 80 ° C. for 20 minutes. The transfer pattern on the surface of the molded product thus obtained was evaluated by the following evaluation methods, and the evaluation results are also shown in Table 2.

(1) Spreadability: The spread state of the printed pattern layer when the hydraulic transfer sheet is floated on the water surface is visually observed and evaluated according to the following evaluation criteria. ○: The pattern is not distorted and spreads in a highly uniform state. ◇: The pattern is slightly distorted, but it is not a problem in practical use. △: The dispersibility is insufficient, and part of the pattern is also recognized.

(2) Transferability: The appearance of the printed pattern layer formed on the surface of the molded product is visually observed and evaluated according to the following evaluation criteria. ○: There is no pattern break, and a clear printed pattern is formed. ◇: The range where pattern breaks occur very slightly but is not a practical problem. △: Pattern breaks occur and a uniform pattern appearance cannot be obtained.

(3) Adhesiveness: JIS-K-5400,
An adhesion test (clearance interval 1 mm, number of squares 100) is performed by "8.5.1 Cross cut method", and the evaluation is made according to the following evaluation criteria. ◯: No trace of peeling was observed, and the adhesion was extremely good (10
0/100) ◇; Adhesion is good with slight cracks in the coating along the cut surface (100/100) △: Slight peeling is observed, but practical use range (90
Or more / 100) x: Peeling is recognized (less than 90/100)

[0030]

[Table 2]

[0031]

The binder resin of the primer for a hydraulic transfer sheet provided by the present invention is obtained by graft-polymerizing a specific amount of the above specific alkoxy / (poly) alkylene glycol / mono (meth) acrylate onto chlorinated polypropylene. Since it is composed of a polymer, the primer containing this as a binder resin can be applied to polyolefin resin molded products that were difficult to apply in the past, especially to polyolefin resin molded products that are not subjected to surface treatment to improve adhesion. On the other hand, since it is possible to form a printed pattern layer having excellent adhesiveness, and since the binder resin itself is imparted with hydrophilicity, the organic solvent composition of the primer may be a hydrophobic solvent. In addition, the spreadability of the printed pattern on the water surface is good, and a clear transfer pattern can be formed without the pattern being distorted. There is an advantage to say. Further, by using the binder resin of the present invention, the solvent composition of the primer for hydraulic transfer sheet does not necessarily have to be composed of a hydrophilic solvent, and it has become possible to compose a hydrophobic solvent. It also reduces costs and is excellent in practicality.

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-9-1996 (JP, A) JP-A-63-197685 (JP, A) JP-A-63-60782 (JP, A) JP-A-6- 16847 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B44C 1/175

Claims (4)

(57) [Claims] 1. A primer capable of dissolving or swelling a print pattern layer by applying the print pattern layer-formed surface of a water-based transfer sheet comprising a water-soluble or water-swellable film having the print pattern layer formed thereon. Which is a binder for an alkoxy. (Poly) alkylene glycol mono (meth) acrylate 5 to 50% by weight, a chlorinated polypropylene resin 5 to 50% by weight and a polymerizable unsaturated group-containing vinyl compound 0 to A binder resin for a primer for a hydraulic transfer sheet, which is a graft copolymer comprising 90% by weight. 2. The alkoxy. (Poly) alkylene glycol mono (meth) acrylate is alkoxy.
The binder resin for a primer for a hydraulic transfer sheet according to claim 1, which is polyethylene glycol monomethacrylate. 3. The binder resin for a primer for a hydraulic transfer sheet according to claim 1, wherein the chlorinated polypropylene has a chlorination rate of 15 to 50%. 4. The vinyl compound containing a polymerizable unsaturated group is methyl (meth) acrylate, ethyl (meth) acrylate, -n-butyl (meth) acrylate, -iso-butyl (meth) acrylate, (Meth) acrylic acid-ter
t-butyl, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic acid-
2. At least one selected from the group consisting of n-lauryl, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate.
Binder resin of the described hydraulic transfer sheet primer.