JP2909015B2 - Vinyl chloride resin composition for overlay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overlay vinyl chloride resin composition (hereinafter simply referred to as a vinyl chloride resin composition) useful as an overlay sheet used on the surface of cash cards, hospital consultation cards, and the like. ).

[0002]

2. Description of the Related Art Cards such as cash cards and medical examination cards in hospitals use a vinyl chloride resin sheet as a core material and have an overlay sheet attached to one or both surfaces thereof. Printing is performed, and a transparent sheet is used for the overlay sheet. The card is used by engraving its name, address, date of birth, etc. on its surface with a known stamping machine. However, it is difficult to distinguish the color of the core material from the color of the embossed part with this engraving, so the engraved protrusions are usually top-printed in gold or other colors by hot stamping etc. I have.

[0003]

However, when cards are used more widely as at present, the top printing increases the cost of the card, and hospital consultation tickets and the like include the first and last name and the date of birth. Although the contents differ depending on the individual, the date must be issued on the spot on the day,
Therefore, it is impossible to perform engraving and top printing in advance, and even if engraving is possible, a hot stamping machine is required for each use place. Therefore, maintaining transparency without damaging the printed content of the core material even when the core material and the overlay sheet are bonded together, and whitening the letters and numbers on the overlay sheet simply by engraving with an engraving machine There is a need for an overlay sheet that can be distinguished from the core material.

[0004]

SUMMARY OF THE INVENTION The present invention has the disadvantages described above,
The present invention relates to a vinyl chloride-based resin composition which provides an overlay sheet having the above-mentioned preferable physical properties, which solves the above-mentioned disadvantages. Inorganic filler mainly composed of feldspar-based mineral is added to 100 parts by weight of resin.
4545 parts by weight.
The vinyl resin composition chloride, it by blending the plasticizer 25 parts by weight or less relative to 100 parts by weight of the base resin, also
The inorganic filler has an average particle size of 3 to 8.5 μm and a specific surface area of 0.5.
Preferably, it is about 3 m ² / g.

[0005]

Embodiments of the present invention will be described below in detail. The vinyl chloride resin used as a main component of the base resin in the vinyl chloride resin composition of the present invention is mainly manufactured by a suspension polymerization method, and has a particle diameter of
A vinyl chloride homopolymer, a copolymer or a graft polymer with vinyl chloride of about 100 to 300 μm, and the like. Among these, a vinyl chloride homopolymer having a degree of polymerization of 300 to 1,500 is preferred from the viewpoint of processability and resin suitability. As the copolymer or graft polymer, post-chlorinated vinyl chloride resin, vinyl chloride-vinyl acetate resin, ethylene- Vinyl chloride resin, cross-linked vinyl chloride resin, ethylene-vinyl chloride block polymer, ethylene-vinyl chloride-
Examples thereof include a vinyl acetate graft polymer, and these may be used in combination of two or more.

Examples of the acrylic resin used in combination with the base resin include methyl methacrylate, a copolymer of methyl methacrylate and an acrylate ester having 1 to 4 carbon atoms, and the like. (ASDM D-1238, 230 ℃, 3.8kg)
If it is larger than 100 g / 10 min, the flowability increases and processing becomes difficult, and if it is smaller than 0.1 g / 10 min, the mechanical strength is reduced.
-100 g / 10 min, particularly preferably 1-50 g / 10 min.

[0007] The base resin is the above-mentioned vinyl chloride resin 50 to 95
It is necessary that the acrylic resin is mixed with 5 to 50% by weight of the acrylic resin. Here, in a base resin in which the vinyl chloride resin is less than 50% by weight and the remainder is made of an acrylic resin, the mechanical strength of the formed sheet tends to decrease. When the acrylic resin is used, the transparency of the formed sheet becomes 70 or more in haze value, and the sheet becomes cloudy without transparency.

[0008] The vinyl chloride resin composition of the present invention comprises 5 to 45 parts by weight of an inorganic filler mainly composed of feldspar-based mineral with respect to 100 parts by weight of the base resin. But,
When the amount is less than 5 parts by weight, the whitening property is hardly generated, and when the amount exceeds 45 parts by weight, the transparency of the formed sheet is determined by the value of haze.
When it is 70 or more, transparency is impaired, and impact strength decreases. Incidentally, the inorganic filler as well as the give favorable results in terms of whitening resistance at the time of transparency and inscription sheet formed, albite to, jadeite, Na ₂ O-Al ₂ O such as nepheline _3- SiO ₂ is most suitable. Similarly, the refractive index is between the refractive index of the vinyl chloride resin and the acrylic resin, that is, generally, the refractive index of the vinyl chloride resin is about 1.54, the refractive index of the acrylic resin is said to be about 1.49 Therefore, a material having a refractive index in the range is desirable. Further, for the same reason, the particle size is 3 to 8.5 μm.
m and a specific surface area in the range of 0.5 to ³ m ² / g are preferred.

The vinyl chloride resin composition of the present invention also comprises
A plasticizer can be further added in an amount of 25 parts by weight or less based on 100 parts by weight of the base resin. If the amount exceeds 25 parts by weight, the formed sheet becomes soft and the whitening property at the time of engraving is impaired. The plasticizer includes dioctyl phthalate (hereinafter referred to as DOP), dibutyl phthalate,
Phthalates such as butyl benzyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate and diundecyl phthalate; aliphatic dibasic esters such as dioctyl adipate, n-butyl adipate and dibutyl sebacate; penta Glycol esters such as erythritol ester and diethylene glycol benzoate; fatty acid esters such as methyl acetyl ricinoleate; phosphate esters such as tricresyl phosphate and triphenyl phosphate; epoxidized soybean oil (hereinafter referred to as ESO); Epoxidized oils such as linseed oil; acetyl tributyl citrate, acetyl trioctyl citrate, tri-
citric acid esters such as n-butyl citrate; and plasticizers of various structures such as trialkyl trimellitate, tetra-n-octyl pyromellitate, polypropylene adipate, and polyester.

The above-mentioned vinyl chloride-based resin composition contains a calcium-based or zinc-based or composite thereof, a tin-based stabilizer, a lubricant, a reinforcing agent, a pigment, etc., depending on the processing conditions and processing method. May be added.
Although a BS resin or the like may be added, the MBS resin has a butadiene ratio of 60% by weight or more and a ratio of methyl methacrylate of 14 to 20% by weight further enhances whitening at the time of engraving. Has been confirmed to be.

The thus obtained vinyl chloride resin composition of the present invention is mixed with a Henschel mixer, a ribbon blender, or the like, and formed into a sheet by extrusion or calendering to form an overlay sheet. This overlay sheet does not lose transparency so as not to damage the printed content of the core material even when it is bonded to the core material, and the engraved letters and numbers are whitened just by engraving with an engraving machine. It has the advantage that it can be distinguished.

[0012]

EXAMPLES The present invention will be described below with reference to Examples and Comparative Examples.
The measuring method of the whitening property is as follows. (Details of components) ・ Vinyl chloride resin: TK-700 [Shin-Etsu Chemical Co., Ltd. product name, polymerization degree 700, refractive index 1.54] TK-1000 [Same as above, polymerization degree 1,000, refractive index 1.54] ・ Acrylic Base resin: H-602 [Mitsubishi Rayon Co., Ltd. product name, refractive index 1.49] ACRYPET MF [same as above, refractive index 1.49, abbreviated as MF in the table]-Inorganic filler: Kaseki / MINEX7 [Shiraishi calcium] Product name, particle size
4.5 μm, specific surface area 1.4 m ² / g, refractive index 1.53] Kaseki / MINEX4 [same, particle size 7.5 μm, specific surface area 0.9 m ² /
g, refractive index 1.53]-Tin stabilizer: ADK STAB 465 [trade name of Asahi Denka Kogyo Co., Ltd.]-Plasticizer: DOP [Dainippon Ink Chemical Industry Co., Ltd.] ESO [Asahi Denka Kogyo Co., Ltd.] Lubricant: Stearic acid / Sakura [trade name, manufactured by NOF Corporation] Reinforcer: MBS resin, B-22 [trade name, manufactured by Kanegafuchi Chemical Industry Co., Ltd.]

(Measurement Method) Transparency: The measured value of the haze of the obtained vinyl chloride resin sheet according to JIS K-7105 is replaced by the following symbol. ○: less than 40, Δ: 40 to 70, ×: 70 or more ・ Bleaching property: The height of the obtained vinyl chloride resin sheet was about 2 with a stamping machine.
It was stamped with mm, and its whitening property was visually judged based on the following evaluation criteria. [Evaluation criteria] ○: Whole whitening, ×: No partial whitening or whitening

Examples 1 to 9 and Comparative Examples 1 to 4 According to the formulations shown in Table 1, a vinyl chloride resin and an acrylic resin were first blended to prepare 100 parts by weight of a base resin.
Other components were added, and the mixture was mixed and heated to 100 ° C. with a known heater mixer, and then cooled to obtain a vinyl chloride resin composition. Then knead with a Banbury mixer, L
A vinyl chloride resin sheet having a thickness of 0.10 mm was formed by rolling with a four-die calender, and the transparency and whitening property of this sheet were measured. The results as shown in Table 1 were obtained.

[0015]

[Table 1]

[0016]

According to the present invention, when a sheet molded from the vinyl chloride resin composition of the present invention is used for overlaying, there is no decrease in transparency which impairs the printing of the core material, and letters and numerals are in good condition when engraved. Since it is possible to cause whitening, there is an advantage that it is not necessary to perform top printing by hot stamping or the like and increase the number of facilities on the engraved projection.

Claims (3)

(57) [Claims] An inorganic filler containing a feldspar-based mineral as a main component is added to 100 parts by weight of a base resin comprising 50 to 95% by weight of a vinyl chloride resin and 5 to 50% by weight of an acrylic resin.
A vinyl chloride resin composition for an overlay, which is blended in parts by weight. 2. The vinyl chloride resin composition for overlay according to claim 1, further comprising 25 parts by weight or less of a plasticizer based on 100 parts by weight of the base resin. 3. The method according to claim 1, wherein the inorganic filler has an average particle size of 3 to 8.5 μm,
The vinyl chloride resin composition for overlay according to claim 1, which has a specific surface area of 0.5 to ³ m2 / g.