JPH0225496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming patterns on silicone rubber surfaces having low interfacial tension.

Conventionally, as a method for forming a pattern on a silicone rubber surface having low interfacial tension, a pattern is formed on the silicone rubber surface by a method such as printing or electrophotography, and then a pattern is formed on the silicone rubber surface by means such as heat or light. A method of fixing the material, or a method of forming a pattern on an uncured silicone rubber surface, embedding the pattern in the silicone by applying pressure, and then fixing it to the silicone rubber by heating and curing are known. However, since the silicone rubber surface has excellent releasability, the adhesion force with the pattern-forming substance is weak and strong adhesion cannot be obtained.In addition, there is a large difference in interfacial tension between the silicone rubber surface and the pattern-forming substance, so the pattern cannot be formed. It is difficult to form a pattern directly on the silicone rubber surface due to poor wettability of the substance, and has the disadvantage that a clear image cannot be obtained. Not only is it not possible to obtain sufficient adhesive force, but even embedding by pressure has not produced a significant effect.

The present invention solves the drawbacks of these conventional methods and aims to obtain a clear pattern that is firmly adhered to the silicone rubber surface. , and a silicone rubber liquid containing an organosilane or organosiloxane having at least one group selected from a vinyl group, a mercapto group, and a methacrylic group in one molecule, and then applying an ionizing radiation-curable composition onto another support. A radiation-curable composition is prepared in which a pattern is formed by forming a pattern, and then the silicone rubber surface and the pattern surface are laminated so that the silicone rubber surface and the pattern surface are in contact with each other, and the pattern is formed by irradiating ionizing radiation from the support side. , the image is formed on the silicone rubber surface of the substrate by transferring and fixing it onto the silicone rubber surface at the same time as it is cured, and then peeling off the support.

The present invention will be explained below with reference to the drawings. The substrate 1 to which the silicone rubber liquid is applied is not particularly limited, but includes, for example, plastic films such as polypropylene, polyester, vinyl chloride, and polyethylene, and metal foils such as aluminum and copper. Papers such as metal plates, high-quality paper, art paper, and coated paper, as well as laminated combinations of the above-mentioned substrates, can be used.

Next, the silicone rubber liquid that forms the silicone rubber surface 2 is one that cross-links and cures at room temperature or by heating after coating to become a silicone rubber elastic body, in which 90 mol% or more of all organic groups bonded to silicon atoms are methyl. It is best to use a highly polymerized organopolysiloxane (which has excellent ink repulsion properties) as a main component, which includes (1) 90 mol% or more of organic groups whose molecular chain ends are blocked with hydroxyl groups; is a highly polymerized diorganopolysiloxane in which is a methyl group, methylhydrodiene polysiloxane or ethyl polysilicate as a crosslinking agent, and an organic acid metal salt as a condensation catalyst; (2) a highly polymerized diorganopolysiloxane containing a vinyl group; Siloxane (more than 90 mol% of organic groups other than vinyl groups are methyl groups),
(3) High polymerization consisting of methylhydrodiene polysiloxane as a crosslinking agent and a platinum-based catalyst as an addition reaction catalyst, (3) 90 mol% or more of the organic groups whose molecular chain ends are blocked with hydroxyl groups are methyl groups. Examples include silane or low-polymerization siloxane compounds having three or more hydrolyzable groups such as acetoxy groups, amino groups, oxime groups, or propenoxy groups in one molecule as a crosslinking agent. Ru. In the present invention, the types exemplified in (1) or (2) above are particularly preferred.

In addition, organic groups other than methyl groups in the above generally include aryl groups such as phenyl groups, alkenyl groups such as vinyl groups, alkyl groups such as ethyl groups and propyl groups, pattern-substituted alkyl groups such as trifluoropropyl groups, etc. is exemplified, and the interfacial tension of the surface after coating and drying is 20 to 27 dyne/cm. The silicone rubber liquid may be applied using known coating methods such as gravure coating, roll coating, air knife coating, pouring, and dipping. Further, in the present invention, as the silane or siloxane to further improve the adhesion between the ionizing radiation curable composition and the silicone rubber surface, a silane or siloxane having at least one vinyl group, mercapto group, or methacrylic group in one molecule is used. Examples of such compounds include vinyltrichlorosilane, vinyltriethoxysilane, Nallyl gamma aminopropyltrimethoxysilane, vinyltris(2-methoxyethoxysilane), 3-methacryloxypropyltrimethoxysilane, and 3-mercaptopropyl. Silanes such as trimethoxysilane and the above silanes are condensed using an organic acid metal salt as a condensation catalyst.
Molecularly polymerized siloxane, and furthermore, siloxane that is a condensation reaction product of the above-mentioned silane and a low polymerization degree diorganopolysiloxane in which 90 mol% or more of the organic groups whose molecular chains are capped with hydroxyl groups at both ends are methyl groups. I can give an example. The amount of the above silane or siloxane added to silicone rubber is 0.5~
20% by weight is suitable, preferably 1-10% by weight. This is because if it is less than 0.5%, there is no effect on adhesion, and if it is more than 20%, the properties such as releasability and oil repellency of silicone rubber will be impaired.

As the support 3 used in the present invention, one that is easy to peel off after the ionizing radiation-curable composition is cured is used. Specifically, plastic films such as polyethylene, polypropylene, and polyester are used.

Next, the ionizing radiation-curable composition used in the present invention basically consists of an oligomer that is curable by radiation, a monomer, a polymer for adjusting viscosity, and a coloring material such as a pigment dye. Examples of curable oligomers and monomers include prepolymers or oligomers having ethylenically unsaturated bonds in the molecule, such as unsaturated polyesters, polyester acrylates, epoxy acrylates, urethane acrylates, polyether acrylates, polyol acrylates, and melamine. One or more of various acrylates such as acrylate, various methacrylates such as polyester methacrylate, epoxy methacrylate, urethane methacrylate, polyether methacrylate, polyol methacrylate, and melamine methacrylate, and a monomer having an ethylenically unsaturated bond in the molecule. For example, styrenic monomers such as styrene and α-methylstyrene; acrylics such as methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, methquibutyl acrylate, and phenyl acrylate. Acid esters; methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxytityl methacrylate,
Methacrylic acid esters such as phenyl methacrylate and lauryl methacrylate; unsaturated carboxylic acid amides such as acrylamide and methacrylamide; 2-(N,N-dimethylamino)ethyl acrylate;
2-(N,N-dimethylamino)ethyl methacrylate, 2-(N,N-dibenzylamino)ethyl acrylate, (N,N-dimethylamino)methyl methacrylate, 2-(N,N- Substituted amino alcohol esters of unsaturated acids such as diethylamino)propyl; ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate,
Polyfunctional compounds such as 1,6-hexanediol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and/or in molecules Polythiol compounds having two or more thiol groups such as trimethylolpropane trithioglycolate,
It can be made by mixing trimethylolpropane trithiopropionate, pentaerythritol tetrathioglycolate, etc.

Polymers used for viscosity adjustment are those that are compatible with the above-mentioned reactive oligomers and monomers, specifically polyester resins, polyurethane resins, polyvinyl acetate resins, diene elastomers, alkyd resins, and petroleum resins. etc. can be used. Pigments and dyes that are commonly used in printing inks may be used. The method of providing the pattern 4 of the ionizing radiation-curable composition on the support 3 includes hand-painting the cured composition, offset printing,
By known printing means such as screen printing, or
Electronic photographs may also be used.

As described above, the silicone rubber liquid is applied and cured on the substrate 1, and a pattern 4 made of the ionizing radiation-curable composition is provided on another support, and then both are separated from the silicone rubber surface 2 and the pattern surface. The substrates are stacked so that they are in contact with each other, and ionizing radiation 5 is irradiated from the support side as shown in FIG.

Such ionizing radiation is emitted from various electron beam accelerators such as Kotscroft-Walton type, Van de Graaff type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type,
Using electron beams, X-rays, gamma rays, or the like having an energy in the range of 1000 KeV, preferably 100 to 300 KeV, the pattern made of the ionizing radiation-curable composition is cured and fixed to the silicone rubber surface at the same time by irradiation. Next, as shown in FIG. 2, the support 3 is peeled off, and the ionizing radiation curable composition is cured on the silicone rubber surface of the substrate, forming a patterned cured product 4'.

In the present invention, the reason why the ionizing radiation-curable composition firmly adheres and adheres to the silicone rubber surface of the substrate is that it is irradiated with high-energy ionizing radiation, such as the above-mentioned electron beams, X-rays, and γ-rays. ,
Radicals are generated in the siloxane main chain of silicone rubber, and at the same time as the siloxane crosslinks, a portion of it reacts and bonds with the opposing ionizing radiation-curable composition, and radicals are also generated in the ionizing radiation-curable composition. It is thought that this is because, at the same time as the ionizing radiation-curable composition is crosslinked, a portion of the siloxane reacts with the siloxane in contact with the ionizing radiation-curable composition and bonds with the ionizing radiation-curable composition.

According to the present invention as described above, the pattern is not provided directly on the silicone rubber coated surface of the substrate;
Since the image is once formed on a support and then transferred, it is possible to overcome the disadvantage of the conventional method in which clear images cannot be obtained due to poor wetting, and it also uses an ionizing radiation-curable composition. It is a decorative material that takes advantage of the water repellency, oil repellency, and heat resistance of silicone rubber. It can be applied to the fields of display materials, advertisements, promotions, etc., and can also be applied to the field of waterless planographic printing plates.

The present invention will be explained in more detail with reference to Examples below.

Example 1 The following components were mixed in a premixer to form a paste, and then kneaded in a three-roll mill to obtain the following composition.

Deismocol 130 (linear polyurethane manufactured by Sumitomo Bayer Urethane) 10 parts by weight Aronix M5700 (oligoester acrylate manufactured by Toagosei) 55 parts by weight diethylene glycol diacrylate 10 parts by weight Carbon black 20 parts by weight The obtained composition was formed into a polyester film with a thickness of 25μ. A print was made by offset printing on top. On the other hand, silicone (KS774) manufactured by Shin-Etsu Silicone Co., Ltd. was applied to the polyethylene surface of the composite paper made by laminating polyethylene and high-quality paper, dried,
After curing, it is laminated with a polyester film provided with a patterned image prepared in advance, and then the polyester film is heated at an accelerating voltage of 180 kV using a low-energy electron beam accelerator (Electro Curtain CB20d50/30 manufactured by Energy Seince).
The composition was irradiated with an electron beam at a dose of 10 Mrad to adhere to the silicone-coated surface, and when the polyester film was then peeled off, the composition remained on the silicone-coated surface and only the polyester film could be easily peeled off. In this way, a clear image firmly adhered to the silicone surface could be obtained.

Example 2 The following ingredients were milled using a three-roll mill to obtain a composition.

Califrex 1107 (SIS rubber made by Ciel Chemical)
10 parts by weight RA1050 (Mitsui Toatsu polyfunctional polyester acrylate) 55 parts by weight Carbon black 20 parts by weight The composition was screen printed on a 25 μm thick polyester film, and the same procedure as in Example 1 was carried out using silicone (Shin-Etsu Co., Ltd.). silicone
KS702) coated with a base material (polyethylene, high-quality paper laminate) and irradiated with electron beam.
Irradiation was performed at 10 Mrad accelerating voltage 180 kV. The polyester film was peeled off to obtain a clear image on the silicone coated surface.

Example 3 Using polyethylene laminate paper as the base material,
The following silicone was applied, dried, and cured to produce a silicone-coated base material.

Silicone rubber KS774 50 parts by weight Methacrylic silane KBM503 3 (all manufactured by Shin-Etsu Silicone) Toluene 950 A polyester film provided with a patterned image produced in the same manner as in Example 1 was laminated with a silicone-coated base material, and then, Low energy electron beam accelerator (Energy Science Electro Curtain CB20d50/
30), the composition was irradiated with an electron beam at a dose of 10 Mrad to solidify and adhere.

Then, by peeling off the polyester film, it was possible to obtain a clear image that was more firmly adhered to the silicone surface than in Example 1.

Example 4 An image was formed on a polyester film in the same manner as in Example 1. Next, the following silicone was applied to a base material (aluminum foil polyethylene laminate film) and dried.

Silicone rubber KS705F 50 parts by weight Mercapto-based siloxane SH-10 3 (Shin-Etsu Silicone) Toluene 950 After lamination in the same manner as in Example 1,
The polyester film was peeled off by electron beam irradiation (irradiation dose: 10 Mrad), and a clear image that was more firmly adhered to the silicone surface than in Example 2 could be obtained.

Example 5 The following composition was kneaded using three rolls to obtain a cured composition.

Califrex 1107 (SIS made by Ciel Chemical)
10 parts by weight RA1050 (Mitsui Toatsu polyfunctional polyester acrylate) 55 〃 Carbon black 20 〃 Thickness was determined by screen printing using the composition
The pattern was printed on a 25μ polyester film.

Polyester film (thickness
100μ) was coated with the following silicone, dried and cured.

Silicone rubber KS772 50 parts by weight Vinyl silane A clear image that was more firmly adhered to the silicone surface than in Example 2 was obtained.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views showing the image forming method of the present invention. 1...Substrate, 2...Silicone rubber surface, 3...
Support, 4... Pattern, 4'... Cured product, 5... Ionizing radiation.

Claims (1)

[Claims] 1 A pattern made of an ionizing radiation curable composition is formed on a support, and 1
An interfacial tension of 20~20% obtained by applying and curing a silicone rubber liquid containing organosilane or organosiloxane having at least one group selected from vinyl, mercapto, and methacrylic groups in the molecule.
The silicone rubber surfaces of 27 dyne/cm are overlapped so that the pattern and the silicone rubber surface are in contact with each other, and then ionizing radiation is irradiated from the support side to cure the ionizing radiation-curable composition in which the pattern has been formed. An image forming method comprising the step of forming an image on the silicone rubber surface by simultaneously transferring and fixing the image onto the silicone rubber surface and then peeling off the support.