JPS6076400A - Transfer film made of vinyl chloride group resin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved vinyl chloride resin transfer film.

Various methods are known as printing methods for plastic molded products, but among them, thermal transfer printing is a method that is easy to print on molded products other than film and sheet shapes, such as silk screen printing. Compared to the two methods, this method has the advantages of being able to print in multiple colors at the same time and having a simple printing operation process, making it an excellent method.

The above-mentioned thermal transfer printing method C2 has a problem in that it requires a large amount of printing on special coated paper, polyethylene film, polypropylene film, cellophane, etc. in advance.

The present inventors have discovered that such conventional expensive coated transfer paper,
As a result of examining the possibility of using a vinyl chloride resin film, which is inexpensive and has excellent printability, as a transfer film instead of a transfer film, we found that when the surface of this resin film is treated with low-temperature plasma of inorganic gas, the treated surface The so-called crosslinked layer in which polymer molecules are three-dimensionally crosslinked is 0.0
It is formed with a thickness of approximately 1 to 1 μm, and it has been confirmed that the resulting modification of surface properties (improvement of hydrophilicity, heat resistance, solvent resistance, and oil resistance) is extremely advantageous for application as a transfer film. 5 The present invention has been achieved.

That is, the present invention relates to a vinyl chloride resin transfer film C2 which is formed by performing transfer ink printing on a vinyl chloride resin film whose surface has been treated with low-temperature plasma of an inorganic gas, and which has the following advantages. or have characteristics.

■ When PVC printing ink is used as a transfer ink, the vinyl chloride resin film whose surface has been surface-treated with inorganic gas low-temperature plasma does not adhere tightly to the film surface and can be easily peeled off. Therefore, it is easily and completely firmly transferred to the surface of a vinyl chloride resin molded article, which is a printing object (transferring object), by heating and pressing.

■ As mentioned above, the crosslinked layer is formed on the low temperature plasma treated surface, and therefore it has excellent heat resistance.
No softening occurs even when subjected to heating H- operation.

(2) Even though the crosslinked layer is formed by low-temperature plasma treatment, the flexibility of the film is not lost at all, so the workability during the transfer operation is excellent and the shape of the printing material can be sufficiently followed.

- Since the low-temperature plasma treated surface is hydrophilic, emulsion-based transfer inks can also be used.

■ For the transfer operation using heat and pressure, a laminator machine for vinyl chloride resin or an extrusion laminator can be used as is.

(2) By applying pressure with an embossing roll during the transfer operation, transfer printing and embossing can be performed simultaneously on the two printing materials C.

The suitability of printing ink for plastics differs depending on the type of plastic, so the ink used in transfer printing is selected depending on the material and type of the printing medium.For example, if the printing medium is soft, In the case of vinyl chloride resin molded products (films, etc.), consider the specificity of the chemical structure of this soft vinyl chloride resin and the influence of additives such as plasticizers and stabilizers, and use other polyethylene, A special ink (PVC printing ink VB, VOH1VSP) that is quite different from printing ink for polypropylene is used. However, the present inventors discovered for the first time that this printing ink for PVC does not adhere tightly to a PVC resin film treated with low-temperature plasma of an inorganic gas, and is easily peelable. This is what happened.

The vinyl chloride resin used in the present invention includes:

Any of polyvinyl chloride and a copolymer mainly composed of vinyl chloride may be used. In this case, the comonomer copolymerized with vinyl chloride includes vinyl ester, vinyl ether, acrylic acid or methacrylic acid and its ester,
maleic acid or fumaric acid or their esters;
Examples include maleic anhydride, aromatic vinyl compounds, vinylidene halides, acrylonitrile or methacrylonitrile, and olefins such as ethylene and propylene.

A plasticizer is generally added to these vinyl chloride resins in order to adjust the hardness and flexibility of the transfer film substrate to be produced. Examples of the plasticizer include phthalic acid esters such as dioctyl phthalate, dibutyl phthalate, and butylbenzyl phthalate, aliphatic dibasic acid esters such as dioctyl adipate and dibutyl sebacate, glycol esters such as pentaerythritol ester and diethylene glycol benzoate, and acetyl ricinoleic acid. Fatty acid esters such as methyl, phosphate esters such as tricresyl phosphate and triphenyl phosphate, epoxidized oils such as epoxidized soybean oil and epoxidized linseed oil, citric acid esters such as acetyl tributyl citrate and acetyl trioctyl citrate. , trialkyl trimellitate, tetra-n-octylpyromellitate-1, polypropylene adipate, and other polyester plasticizers.

In order to further enhance the effect of forming a crosslinked layer on the surface of the film by low-temperature plasma treatment, which will be described later, it is particularly desirable to select and use an aromatic plasticizer as the plasticizer. The aromatic plasticizer may be used in an amount of at least 25% by weight of the total amount of plasticizer to be blended,
It is not necessarily necessary that the entire amount be aromatic. The amount of plasticizer added to adjust the hardness and flexibility of the film base is usually 5 to 100 PHR, preferably 15 to 50 PHR.

Additionally, carboxylic acids such as calcium stearate, zinc stearate, lead stearate, barium stearate, and cadmium stearate are used as additives for vinyl chloride resins to improve properties such as lubricity and stability. metal salts, tribasic lead sulfate, dibasic lead phosphite,
Organotin compounds such as dibutyltin dilaurate, di-octyltin malate, di-n-octyltin mercaptite, organic acid esters such as butyl stearate, fatty acid amides such as ethylene bisstearamide, higher fatty acids and their Examples include ester and polyethylene wax.

Other various additives used in the molding of vinyl chloride resins include fillers, heat resistance improvers, antioxidants, ultraviolet absorbers, antistatic agents, dropless agents, pigments, dyes, crosslinking aids, etc. be done.

Furthermore, various polymeric rubber elastic bodies may be blended,
Examples of this polymeric rubber elastic material include ethylene-vinyl acetate copolymer, acrylonitrile-butadiene copolymer, styrene-acrylonitrile copolymer, methyl methacrylate,
-Torstyrene-butadiene copolymer, acrylonitrile-styrene-butadiene copolymer, urethane elastomer, polyamide resin, ethylene-propylene-genta polymer, epoxy-modified polybutadiene resin, and the like.

The melt extrusion method (
Any film forming method conventionally used in molding vinyl chloride resins may be used, such as T-die method, inflation method), calendar molding method, etc., and there are no particular limitations.

In invention C:, it is necessary to surface-treat the film obtained as described above with low-temperature plasma of an inorganic gas, and a specific method for carrying out this low-temperature plasma treatment is as follows:
For example, an internal electrode type low-temperature plasma generator having two internal discharge electrodes that can be depressurized is used, a film is placed in the device, and a discharge voltage is applied between the electrodes while an inorganic gas is passed under reduced pressure. Method C2 is used in which the surface of the film is treated by generating low-temperature plasma of inorganic gas by causing glow discharge.

Inorganic gases used here include helium, neon, argon, nitrogen, gas, air, nitrous oxide, -nitrogen oxide, nitrogen dioxide, -carbon oxide, carbon dioxide, bromine cyanide, sulfur dioxide gas, and hydrogen sulfide. etc., and these are 1
The seeds can be used alone or in combination of two or more. In the present invention, the inorganic gas is preferably -carbon oxide or argon, and it is particularly preferable that -carbon oxide is contained in an amount of 5% or more.

The pressure of the gas atmosphere inside the low temperature plasma generator is 0.
．． 001 to 10 Torr (preferably 0.05 to 5 Torr), and under such gas pressure the frequency between the electrodes is several kHz = 100 MHz, several W to several hundred KW.
A stable glow discharge can be caused by applying high frequency power of . Note that as the discharge frequency band, in addition to the above-mentioned high frequency, low frequency, microwave, direct current, etc. can be used.

In addition to the internal electrode type described above, the low-temperature plasma generator may be an external electrode type, or may be a coil type, either capacitively coupled or inductively coupled. There is no particular restriction on the shape of the electrodes, and the input side 11& pole and the ground side electrode may have the same shape or different shapes, and they can be in various shapes such as a flat plate, ring shape, rod shape, cylinder shape, etc. may be of the type in which the metal inner wall of the device is grounded as one electrode.

However, no matter what method is used, it is necessary to prevent the film surface from deteriorating due to discharge heat.
The low-temperature plasma treatment time varies depending on the type of equipment, applied voltage, etc., but in normal cases, a few seconds to several tens of minutes is sufficient.

In the present invention, a desired pattern is printed on the surface of the film treated with low-temperature plasma using an appropriate transfer ink. As this printing method, gravure printing, offset printing, screen printing, etc. are used.

In addition, if surface characteristics after transfer are required, it is best to coat the surface printed with the transfer ink in advance with various surface treatment agents in combination with the required performance C2, and in this case, the surface treatment agents include: Any material such as acrylic, acrylic/polyvinyl chloride, urethane, silicone, etc. that does not adhere to the low-temperature plasma-treated surface and has good wettability can be used.

In addition, the appropriate transfer ink is selected and used depending on the material of the object to be transferred, but by coating the print surface of the transfer ink with an adhesive that becomes adhesive when heated, each transfer ink is uniquely made. It is possible to use a variety of materials without being limited to these. For example, if the material to be transferred is vinyl chloride resin, the transfer ink can be used in addition to printing ink for vinyl chloride, acrylic, acrylic/salt, ethylene-vinyl acetate, ethylene-vinyl acetate/salt. Excellent transfer is also possible by using ink. In addition, if the material to be transferred is olefin-based, a PVC printing ink is used as the transfer ink, and a polyester-based, urethane-based, etc. It is also possible to adopt a structure in which the material is coated with a chemical agent.

In any case, selection of transfer ink, coating of adhesive, etc. f: Various transfer targets such as vinyl chloride resin,
Good transfer to plastics such as polyethylene, polypropylene, and polyester, metals such as iron, copper, and aluminum, wood materials, fiber materials, etc. is possible.

Methods for transferring, for example, a plastic molded product 52 using the transfer film of the present invention include an extrusion lamination method for transferring onto a high-temperature resin molded product coming from an extrusion molding machine, a calendar topping method, and a film sheet method. Thermal lamination method, which transfers the image by heating it, hot stamping method, etc. are used.

Next, a specific example will be given.

Example 1 100 parts of vinyl chloride resin (wherein C indicates parts by weight), 35 parts of plasticizer (25 parts of DOP, 10 parts of DBP),
A compound consisting of 0.5 parts of barium stearate) and 2 parts of tin laurate was formed into a film using the T-die method (two-fold process).The film was set in a plasma generator, and the pressure inside the equipment was reduced to 10-4. After that, an equal volume of Co-Ar mixed gas was introduced, and the inside of the device under this mixed gas flow was 0.1
After adjusting and holding the film, a high frequency power of 13.56 MHz 1 kW was applied to generate low temperature plasma, and the film was subjected to low temperature plasma treatment for 3 minutes.

Next, a wood grain pattern is printed on this treated film f2 using a gravure printing method using gravure ink for PVC (Dainichiseika S Interf), the solvent is dried in a drying oven at 60°C, and the printed film is wound. I took it.

A transfer test was conducted using the transfer film thus obtained. That is, the tuft film was transferred using a heating roll using a 90 mm extruder at a transfer temperature of 120 to 130°C. The results were as shown in Table 1. For comparison, the same table also includes test results for two transfer films that were not subjected to low-temperature plasma treatment.

Ink adhesion after transfer: According to the test method of TIS D 0202 Table 1 (Cellotape: 100 parts of vinyl chloride resin, 20 parts of plasticizer (DOP), A blend consisting of 5 parts of epoxidized soybean oil and 3 parts of Ba--Zn stabilizer was formed into a film by a calendering method. This film was set in a plasma generator, and after reducing the pressure inside the device to 10'), atmospheric air was introduced, and then CO gas was introduced, so that the atmospheric partial pressure inside the device was 0.1 torr, and the CO gas partial pressure was 0. After adjusting and maintaining the temperature at .4 torr, a high frequency power of 110 kHz and 5 kW was applied to generate a 4M plasma, and the film was processed for 1 minute.

Next, a 4-color floral pattern was printed on this treated film using offset ink for vinyl chloride (Dainichiseika V9 ink) using a general offset printing machine C: at 50°C.
The film was dried and the printed film was wound up.

A transfer test was conducted using the transfer film thus obtained. That is, a film made from the same formulation as above is passed over a heated roll, and the L transfer film is laminated thereon at a transfer temperature of 150 to 160°C.
Transcribed by. Further, this laminated state was embossed by pressing it onto an embossing roll, and the embossing suitability was tested.

The results were as shown in Table 2. For comparison, test results for transfer films that were not subjected to low-temperature plasma treatment are also listed in the same table.

Table 2 Example 3 A polyvinyl chloride resin film treated with low-temperature plasma in the same manner as in Example 2 was coated with a dry film of 5 μm of urethane material (Dainichiseika PTOV-1 Matsuto Medium) using a gravure coater, and then gravure printing was performed. The wood grain pattern was printed using PVC-based ink (Dainichiseika S Ink). Furthermore, a dry film of 6 μm of an acrylic adhesive (KV-631, manufactured by Konishi Co., Ltd.) that thermally fuses with ABS was applied to the printed surface. Using CABS resin (Nippon Gosei J8R42) in the extruder, the 1-shaped edge material was extruded into a different shape, and the processed film (slit to a width of 20 mm) was transferred using the heat of the extruded resin. did.

In the obtained profile extrusion molded product, the printed layer and A-BS were completely adhered to each other via the acrylic adhesive and did not peel off. Furthermore, the surface after peeling off the plasma treated film (transfer film) is coated with urethane paint, so
It has excellent solvent resistance, water resistance, and abrasion resistance. Also, the urethane paint and the printed layer did not peel off in the cellophane tape test.

agent 19-

Claims (1)

[Claims] 1. A vinyl chloride resin transfer film formed by printing transfer ink on a vinyl chloride resin film surface-treated with low-temperature plasma of an inorganic gas. 2. The vinyl chloride resin film is blended with an aromatic plasticizer. The transfer film according to claim 1, which is a soft film.