JPH0741707A - Marking agents and silicone rubber moldings - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a high-quality marking agent which can be suitably used for marking a silicone rubber molded product by providing a display portion that looks different in two colors depending on the viewpoint. [Structure] Adhesion rate 3 on the surface of mica with a particle size of 5-140 μm
A marking agent comprising a curable silicone rubber composition in which a pearling agent coated with titanium dioxide in the range of 5 to 60% and a colored pigment are uniformly dispersed, and a marking agent printed with the marking agent. Provide a silicone rubber molded product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marking agent which gives a display portion which looks different in two colors depending on the viewpoint, and a silicone rubber molded article such as a swimming cap marked with this marking agent.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
Display parts such as various patterns and letters are formed on the surface of silicone rubber molded products such as swimming caps for the purpose of decorating them, and transparent or translucent marking agents are used for this purpose. A marking agent is known in which a colored pigment, for example, phthalocyan blue is added to and mixed with a curable silicone rubber-based pigment for coloring.

However, conventional marking agents of this type are
The display part (print) can be obtained by selecting the pigment, but since it is a single color and lacks in brilliance, it has no three-dimensional effect such that the print stands out, and is not interesting.

As an improved product thereof, it is known to give a glittering display by using a monochromatic pearling agent such as silver, and a marking agent colored by mixing such a pearling agent and the above colored pigment. The brightness of is given by the pearlizing agent dispersed in the colored pigment, so that when it is irradiated with light, the brightness of monochromatic colors such as colorless and white is emphasized, and the color due to the colored pigment is diminished. Therefore, in the normal state, the color of the colored pigment appears to be almost white by irradiation, and the addition of the monochromatic pearlizing agent only provides the brightness, and the original color of the colored pigment is impaired. There was a drawback that it became. Therefore, development of a higher quality marking agent is desired.

The present invention has been made in view of the above circumstances.
An object of the present invention is to provide a marking agent capable of giving a print having at the same time a color of a colored pigment and a color having a vivid glossy glossy color depending on the viewpoint, and a silicone rubber molded article printed with the marking agent. To do.

[0006]

Means and Actions for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that a marking agent based on a curable silicone rubber composition contains mica having a particle size of 5 to 140 μm. By mixing a pearlizing agent coated with titanium dioxide on the surface in the range of 35 to 60% in adhesion rate and a colored pigment to uniformly disperse these components, the light-interfering action of the pearling agent from the viewpoint. It is possible to obtain a marking agent that can simultaneously give two different colors to the display part, which are different colors of reflected light that is colored by and colored light that is transmitted by colored pigments. The inventors have found that the silicone rubber molded article can be obtained, and have completed the present invention.

In this case, in the marking agent of the present invention, the color of the pearling agent can be appropriately selected by variously selecting the adhesion rate of titanium oxide, and the desired marking can be obtained by the color pigment to be combined, and particularly, A dark-colored base material that was difficult to give a beautiful and brilliant color,
Especially, N1 to N6 brightness scale (JIS Z872
The effect of printing the color of 1) on the substrate is great. This is because the above-mentioned pearlizing agent reflects a part of the incident light and transmits the remaining complementary color to separate it into a reflected color and a transmitted color. In the case of a color substrate, the color is often reduced because even the complementary color of the transmissive component is reflected, while in the case of a dark substrate, only the original reflected color can be seen because the complementary color is absorbed. It is especially effective.

It should be noted that when a titanium dioxide-coated mica foil is blended with a silicone rubber composition, a silicone rubber molded article excellent in color and luster can be obtained.
As described in JP-A-58924, it is a new finding of the present inventor that a marking agent that gives the above-mentioned two-color display portion can be obtained by using the titanium dioxide-coated mica and a colored pigment in combination. Is.

Therefore, according to the present invention, a curable silicone in which a pearling agent formed by coating titanium dioxide on the surface of a mica having a particle diameter of 5 to 140 μm in an adhesion ratio of 35 to 60% and a colored pigment are uniformly dispersed. (EN) Provided are a marking agent comprising a rubber composition, and a silicone rubber molded article printed with the marking agent.

The present invention will be described in more detail below. The marking agent of the present invention comprises a curable silicone rubber composition in which a titanium dioxide-coated pearlizing agent and a colored pigment are uniformly dispersed.

As the curable silicone rubber composition which is the base of the marking agent of the present invention, a liquid silicone rubber composition is preferable, and a polymerization degree of 100 to 2.0 is particularly preferable.
It is preferable that the main component is a linear siloxane polymer of No. 00, various fillers and additives are mixed, and that a transparent or translucent film is provided. Such silicone rubber compositions include one-component type and two-component type depending on the form, and further, there are condensation curing type, addition curing type, and UV curing type depending on the curing mechanism.

As the condensation curing type, a linear siloxane polymer having a hydroxyl group in the molecule, an alkoxy group, an amino group,
A low molecular weight polyfunctional siloxane having a hydrolyzable group such as an oxime group, an acetoxy group, and a propenoxy group in the molecule is used as a cross-linking agent, and a filler such as fumed silica, quartz powder, and an organic silicon compound is filled to fill the organic layer. Examples include those using a tin compound or an organic titanium compound as a curing accelerator.

The addition-curable type is mainly composed of a linear siloxane polymer having an alkenyl group in the molecule and a siloxane polymer having a hydroxyl group bonded to a silicon atom in the molecule, and a filler such as fumed silica or quartz powder. An example is one that is filled and reacted with platinum or a platinum group compound as a catalyst.

As the UV-curing type, the main component is a linear siloxane polymer having an alkenyl group in the molecule and a siloxane polymer having a mercapto group in the molecule, and a filler such as fumed silica or quartz powder is filled and started. Examples include agents containing benzophenones.

Among these, the addition-crosslinking type is preferable from the viewpoint that the pearly luster effect can be more clearly exhibited and the ease of molding.

Incidentally, other desired components may be added to the curable silicone rubber composition, if necessary, and for example, an adhesion aid or the like may be added as a marking agent in order to obtain self-adhesiveness. it can.

Next, as a pearling agent, a pearling agent whose surface is coated with titanium dioxide is used.

In this case, the adhesion rate of 35 to 60 on the surface of the mica having a particle size of 5 to 140 μm, preferably 10 to 100 μm.
%, Preferably 40 to 55% of a pearlizing agent coated with titanium dioxide is used. If the mica particle size is less than 5 μm, the gloss is insufficient, and if it exceeds 140 μm, the uniformity cannot be obtained. Further, if the adhesion rate of titanium dioxide is less than 35%, the iris color is difficult to appear, and if it exceeds 60%, the pearliness is impaired.

By adjusting the coverage of titanium dioxide within the above range, markings of various colors can be provided.

Specifically as such a pearling agent,
The Iriodin series manufactured by Merck Japan Ltd. is preferably used.

Further, as the colored pigment, for example, phthalocyanine type, quinacridone type, disazo type, condensed azo type,
Examples include isoindolinone-based and perinone-based organic pigments, red iron oxide, ultramarine inorganic pigments, and the like. Among these, organic pigments are preferable. Specific examples include Sopro Toner B-521 and Sopro Toner B-427S manufactured by Sanyo Dye.

The amount of the above-mentioned pearlizing agent is usually 0.1 to 40 parts, preferably 1 to 30 parts, relative to 100 parts (parts by weight, the same applies hereinafter) of the curable silicone rubber composition. The amount of the colored pigment blended is 0.1 to 30 parts, especially 0.5, with respect to 100 parts of the curable silicone rubber composition.
It is preferably about 20 parts. If the content of the pearling agent is less than 0.1 part or the content of the colored pigment is less than 0.1 part, color development may be poor, and the content of the pearling agent exceeds 40 parts. Alternatively, if the amount of the colored pigment exceeds 30 parts, the mechanical strength and elongation of the marking part may be deteriorated and cracking or peeling may occur. It is desirable to determine the blending amounts of the pearlizing agent and the colored pigment depending on the strength of color development of the selected color.

In the present invention, the color of the pearlizing agent can be appropriately selected by adjusting the titanium dioxide deposition rate of the pearling agent within the above range, and various desired color markings can be made depending on the type of the color pigment to be combined. Obtainable.

Further, there is no particular limitation on the method of dispersing the pearlizing agent and the colored pigment in the curable silicone rubber composition, and they can be mixed and dispersed by an ordinary method using a triple roll or the like.

When marking with such a marking agent, the lightness of the substrate is not particularly limited, but the lightness of the substrate is N-1 (black) to N-6 in accordance with JIS Z8721.
It is particularly effective to set it in the (gray) range.

The marking agent of the present invention can be used for various substrates, but it is preferably used for marking silicone rubber moldings such as swimming caps, and the marking method is not particularly limited. A method such as screen printing, spray printing or dip printing can be appropriately selected depending on the shape of the molded product.

Further, after printing the marking agent of the present invention,
It is desirable to heat cure at room temperature to 250 ° C. for 30 seconds to 3 days.

[0028]

EFFECTS OF THE INVENTION According to the marking agent of the present invention, it is possible to obtain, from the viewpoint, a print which gives clear and lustrous glossy color due to the pearling agent and two different colors due to the colored pigment at the same time. Silicone rubber moldings printed with marking agents are of very high quality.

[0029]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following examples, parts are parts by weight.

Example 50 50 parts of dimethylpolysiloxane having a viscosity of 5,000 cs (25 ° C.) blocked at both ends with a dimethylvinylsilyl group, both ends blocked with a dimethylvinylsilyl group, and the total vinyl group content was 0.1 of the number of organic groups
5% dimethyl siloxane (viscosity 5,000,00
0 cs) 10 parts, SiO ₂ units, (CH ₃ ) ₃ SiO _1/2 units, and (CH ₃ ) ₂ (CH ₂ ═CH) SiO _1/2 units in a total amount of 1 mol, and the vinyl group content is 2 mol%. 10 parts of polysiloxane, 6 parts of hydrogen polysiloxane represented by the molecular formula C ₆ H ₅ Si (OSi (CH ₃ ) ₂ H) ₃ , and mica surface coated with titanium dioxide (particle diameter 10 to ₆₀ μm, titanium dioxide Adhesion rate of 52%) Pearliodizing agent Iriodin 225 (manufactured by Merck Japan) having a dichroic effect 20
Parts, organic pigment phthalocyanine blue 10 parts and chloroplatinic acid 0.5 wt% (as pt) ethanol solution 0.00
A mixture of 4 parts was uniformly mixed with a three-roll mill, and these were diluted with toluene to obtain a marking agent.

[Comparative Example] A silver-type monochromatic pearlizing agent Iriodin 103 (manufactured by Merck Japan Ltd., particle size: 5 to 25 μm, titanium dioxide adhesion rate: 30%) was used in place of 20 parts instead of the above pearling agent. A marking agent was obtained in the same manner as in the example.

The marking agents obtained in Examples and Comparative Examples were applied to a cured black silicone rubber plate so as to have a thickness of 40 μm, and heat-cured at 200 ° C. for 300 seconds to evaluate the color tone. As a result, regarding the color tone, the marking agents obtained in the examples showed blue from the front and purple close to red from the slope, whereas the comparative examples were whitish blue from any angle. . Further, in the example, the brightness of the colored itself was strong and clear, but in the comparative example, the brightness of white was strong, but the colored had no brightness.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Nakano 1 Hitomi, Oita, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (3)

[Claims] 1. A curable silicone rubber composition comprising a mica surface having a particle size of 5 to 140 μm and a titanium dioxide coated in the range of an adhesion rate of 35 to 60% and a pearling agent and a colored pigment uniformly dispersed. Marking agent characterized by 2. A silicone rubber molded article, which is printed with the marking agent according to claim 1. 3. The silicone rubber molded article according to claim 2, wherein the silicone rubber molded article is a swimming cap.