JPH0560582A - Manufacture of three-dimensional image display panel - Google Patents

Abstract

PURPOSE:To provide three-dimensional images excellent in closeness to a base, flexibility and durability by stacking optical-setting resin films on the base, and exposing the films to light through a mask so as to harden the same, and removing the unhardened part to form a desired image pattern. CONSTITUTION:A setting resin film 1 is composed of a photopolymerizing resin composition composed of an unsaturated compound capable of photopolymerizing with a linear copolymer and a photopolymerization initiator which is sensitized by active light rays, and more than two layers of films 1 are stacked on a base 2 in a thickness of 0.15 to 2.5mm and are exposed to light through a mask 5 and hardened to form an image pattern thereon. The linear copolymer has a alpha, beta-unsaturated ethylene monomer containing a carboxyl group and another alpha, beta-unsaturated ethylene monomer as its components. Since three-dimensional images are formed in this way, images obtained are excellent in closeness to the base and has flexibility and excellent durability and is therefore not peeld when curved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a stereoscopic image display panel in which an arbitrary image pattern is formed at a predetermined position on a substrate.

Such a display panel can be used for, for example, a vehicle meter or a display panel.

[0003]

2. Description of the Related Art Conventionally, images such as letters and numbers on a display board are often formed on a substrate by printing, and are generally flat images.

However, in recent years, as the trend toward higher grades has increased, studies are being made to make the images three-dimensional from flat ones in order to impart a sense of quality to images such as these letters and numbers.

As a method for obtaining a three-dimensional image on the display board, thick-walled printing, transfer of irregularities by hot stamping, and the like are conceivable, but all of them are complicated in image forming method and poor in mass productivity.

As another method for forming a three-dimensional image pattern such as letters and numbers on a display board, an acrylic polymer (molecular weight of 100,000 to several hundreds of thousands) is used as a binder, and urethane acrylate, epoxy acrylate, polyol acrylate are used. A photo-curable resin film (thickness 10
˜100 μm) on a substrate, and exposing and curing the resin film through a negative mask to form an image of a prescribed shape at a prescribed position on the substrate.
No. 220 is disclosed.

According to the above method, when a photocurable resin film is laminated on a substrate and cured to form a three-dimensional image, the photocurable resin film is, for example, 500.
It is necessary to have a thick wall of about μm.

However, when an attempt is made to form a thick photocurable resin film using the above photopolymerizable resin composition, the solvent contained in the photopolymerizable resin composition is prevented from evaporating, and the solvent is completely removed. If the removal temperature becomes difficult or the drying temperature is raised to accelerate the evaporation, problems such as foaming occur inside the obtained photocurable resin film. Therefore, the image obtained by curing the above-mentioned thick photocurable resin film has a problem that the adhesiveness to the substrate is poor, the flexibility and durability are poor, and peeling easily occurs due to bending.

A photopolymerizable resin composition having an acrylic polymer (molecular weight of 100,000 to several hundreds of thousands) as a binder and urethane acrylate, epoxy acrylate, polyol acrylate or the like as a photopolymerizable resin has poor sensitivity to light. Therefore, even if an attempt is made to form an image by using a thick photocurable resin film made of the composition,
There is also a problem that it is difficult to obtain a predetermined shape.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above drawbacks, and an object thereof is to provide a three-dimensional image excellent in adhesion, flexibility and durability on a predetermined position on a substrate. It is to provide a method for manufacturing a stereoscopic image display panel that can be provided in any shape.

[0011]

The method for producing a stereoscopic image display panel of the present invention comprises the steps of laminating a photocurable resin film on a substrate, exposing it through a mask and curing it, and removing the uncured portion to remove any image. A method of manufacturing a display board for forming a pattern, wherein the photocurable resin film is sensitized by (a) a linear copolymer, (b) a photopolymerizable unsaturated compound and (c) an actinic ray. A photopolymerizable resin composition comprising a photopolymerization initiator as a component, and two or more photocurable resin films are laminated on a substrate to have a thickness of 0.15 to 2.5 mm, and exposed,
It is characterized by curing and forming an image pattern, by which the above objects are achieved.

The present invention will be described below. The linear copolymer (a) used in the present invention is an α, β-unsaturated ethylenic monomer containing a carboxyl group and α, β other than the above.
An unsaturated ethylenic monomer as a constituent.

The α, β-unsaturated ethylenic monomer containing a carboxyl group may be a monomer containing a carboxyl group and copolymerizable with the α, β-unsaturated ethylenic monomer. Examples thereof include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid (anhydride), fumaric acid, and itaconic acid, and α, β-unsaturated ethylene-based monocarboxylic acids other than the above. As the quantity, for example,
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-hexylstyrene, pn-octylstyrene, p-methoxystyrene, p-phenylstyrene, 3,4- Styrenes such as dimethylchlorostyrene; Vinylnaphthalenes such as α-vinylnaphthalene; Ethylene, propylene, butylene or C _{5 to} C ₃₀ and higher α-olefins; Vinyl chloride, vinyl bromide, vinyl fluoride, etc. Vinyl halides; vinyl acetate, vinyl propionate, vinyl butyrate, and other vinyl esters; methyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, N-octyl (meth) acrylate, lauryl (meth) acrylate, (meth) acrylic 2-ethylhexyl, (meth) acrylic acid-2-chloroethyl, alpha-chloro (meth) acrylate, (meth) acrylate, phenyl
(Meth) acrylic acid esters such as dimethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; vinyl ketones such as vinyl methyl ketone and vinyl ethyl ketone; N-vinylpyrrole, N-vinyl N-vinyl compounds such as indole; (meth) acrylonitrile and (meth) acrylic acid amides.

When the amount of the portion corresponding to the α, β-unsaturated ethylenic monomer containing a carboxyl group in the constituent components of the linear copolymer (a) becomes small, it becomes insoluble in an alkaline aqueous solution. When development cannot be performed with an alkaline aqueous solution, and when the amount becomes large, the compatibility with the coating solvent or other components decreases and the resolution also decreases. Therefore, the amount is limited to 10 to 40% by weight, preferably 15%. ~ 35% by weight.

The amount of the components other than the portion corresponding to the α, β-unsaturated ethylenic monomer containing a carboxyl group in the constituents of the linear copolymer (a) is 60 to 90% by weight. .. When the weight average molecular weight of the linear copolymer (a) becomes small, so-called cold flow easily occurs,
On the other hand, if it becomes large, it becomes difficult to dissolve in an alkaline aqueous solution and it becomes difficult to develop, and the resolution is lowered.
However, it is preferably 50,000 to 300,000.

The photopolymerizable unsaturated compound (b) used in the present invention is at least one compound selected from the group consisting of compounds represented by the following general formula (I).

[0017]

[Chemical 2]

In the formula (I), R ¹ and R ² are hydrogen groups or methyl groups, n is an integer of 1 to 15, R ³ is a hydrocarbon group of 1 to 10 carbon atoms, and m is 1 to 100. And X is a divalent hydrocarbon group having 2 to 20 carbon atoms.

Here, the divalent hydrocarbon group represented by X is a hydrocarbon group composed of linear, branched, alicyclic or aromatic moieties, for example, a hexamethylene group or tolylene. Group, isophorone group, tetramethylxylylene group, naphthylene group and the like.

As the method for producing the unsaturated compound (b), any method may be adopted. For example, diisocyanate and diol are mixed and reacted at a ratio matching the composition ratio of the desired compound, and an isocyanate group is added to the terminal. After forming the urethane oligomer having the above, a (meth) acrylate having a hydroxyl group may be added and reacted with the isocyanate group at the terminal. At this time, if necessary, the reaction may be carried out by dissolving in an organic solvent such as ethyl acetate, methyl ethyl ketone, or toluene, and a catalyst such as dibutyltin dilaurate may be added.

When the amount of the unsaturated compound (b) in the photopolymerizable resin composition decreases, the flexibility of the photopolymerizable resin composition layer after exposure and development decreases, and when it increases, cold flow occurs. Since it becomes easy and the resolution decreases, it is 5 to 100 parts by weight of the linear copolymer (a).
It is 150 parts by weight, preferably 10 to 100 parts by weight. The weight average molecular weight of the unsaturated compound (b) is
When it becomes smaller, the flexibility of the photopolymerizable resin composition layer after exposure and development decreases, and when it becomes larger, the development time becomes longer, so 1,000 to 15,000 is preferable, and 1,500 to 10,000 is more preferable. is there.

As the photopolymerization initiator (c) used in the present invention, any photopolymerization initiator (c) having a property of activating the unsaturated compound (b) by actinic rays such as ultraviolet rays and visible rays to initiate polymerization can be used. Good.

As those which are activated by ultraviolet rays, for example, sodium methyldithiocarbamate sulfide,
Sulfides such as tetramethylthiuram monosulfide, diphenylmonosulfide, dibenzothiazoylmonosulfide and disulfide; thioxanthone derivatives such as thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, and 2,4-diethylthioxanthone; hydrazones, azobis (Di) azo compounds such as isobutyronitrile and benzenediazonium; benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, dimethylaminobenzophenone, Michler's ketone, benzylanthraquinone, t-butylanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone , 2-aminoanthraquinone, 2-chloroanthraquinone, benzyl dimethyl ketal, methyl group Aromatic carbonyl compounds such as nyl glyoxylate; Dialkylaminobenzoic acid esters such as methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, butyl p-dimethylaminobenzoate and isopropyl p-diethylaminobenzoate; Peroxides such as benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide; 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine, benzacridine, etc. Acridine derivative; 9,10-dimethylbenzphenazine, 9-
Methylbenzphenazine, phenazine derivatives such as 10-methoxybenzphenazine; quinoxaline derivatives such as 6,4 ′, 4 ″ -trimethoxy-2,3-diphenylquinoxaline; 2,4,5-triphenylimidazoyl dimer can give.

As those which are activated by visible light, for example, 2-nitrofluorene, 2,4,6-triphenylpyrylyl boron tetrafluoride salt, 2,4,6-tris (trichloromethyl)- 1,3,5-triazine,
Examples include 3,3′-carbonylbiscoumarin and thiomichler ketone.

The amount of the photopolymerization initiator (c) in the photopolymerizable resin composition is determined in consideration of the thickness of the photocurable resin film and the irradiation light amount. For example, when the photocurable resin film is thick, it is necessary to reduce the addition amount of the photopolymerization initiator so that the intensity of light received by the upper layer portion and the intensity of light received by the lower layer portion are not significantly different. Further, when it is necessary to shorten the exposure time in the process, it is necessary to increase the addition amount of the photopolymerization initiator. Therefore, the addition amount of the photopolymerization initiator (C) is the linear copolymer ( A) 0.1 to 10 parts by weight with respect to 100 parts by weight.

The composition of the photopolymerizable resin composition used in the present invention is as described above. However, if necessary, a photopolymerizable resin composition which is liquid at room temperature and can be cured by initiating a polymerization reaction by actinic rays. A mer may be added.

Examples of the photopolymerizable monomer include triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, Tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, nonapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) Acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, 2,2-bis [4- (acryloxydiethoxy) Eniru] propane, 2,2-bis [4- (methacryloxydiethoxyphenyl Siji ethoxy) phenyl] propane, 3-phenoxy-2-propanoyl acrylate,
Examples thereof include 1,6-bis [3-acryloxy-2-hydroxypropyl) hexyl ether and urethane polyester acrylate oligomer.

When the amount of the above photopolymerizable monomer added is large, the tackiness of the unexposed portion becomes strong and it becomes difficult to obtain a good pattern. Therefore, 100 parts by weight of the linear copolymer (a) is used. It is preferably added in an amount of 5 to 150 parts by weight, more preferably 10 to 100 parts by weight, based on parts.

In the photopolymerizable resin composition used in the present invention, a plasticizer such as dioctyl phthalate, triethylene glycol diacetate, p-toluene sulfonamide, N-ethyltoluene sulfonamide; hydroquinone, p-methoxy. Thermal polymerization inhibitors such as phenol; stabilizers; ultraviolet absorbers; antioxidants; methyl ethyl ketone,
A solvent such as toluene may be added.

The substrate used in the present invention is not particularly limited, but generally, an acrylic resin,
A plastic plate such as a polycarbonate resin or a polyester resin; a glass plate; a ceramic plate; a metal plate, etc. are preferably used, and in consideration of necessary characteristics such as flexibility, transparency and heat resistance. To be selected.

Further, any image may be printed in advance on these substrates. The photocurable resin film used in the present invention is obtained, for example, by casting a photopolymerizable resin composition on a synthetic resin film, but when the thickness of the photocurable resin film is increased, It is not preferable because the evaporation of the solvent contained in the photopolymerizable resin composition is hindered, and the thickness after drying is usually 50 to
The range is preferably 200 μm.

Therefore, for example, in order to obtain a photocurable resin film having a thickness of 500 μm, it is necessary to form a laminate in which five layers of the photocurable resin film having a thickness of 100 μm are laminated on the substrate by a thermal laminating method or the like. There is.

Further, when the thickness of the laminated photocurable resin film is thin, an image having a three-dimensional effect cannot be expressed, and when it is thick, it is difficult to express a fine image, so the thickness is 0.15. It is limited to the range of up to 2.5 mm, preferably 0.3 to 2 mm.

As a method for forming an image pattern on the above-mentioned substrate, for example, a negative mask for obtaining a predetermined image pattern is superposed on a photopolymerizable resin film laminated on the substrate. A method of irradiating light from a negative mask to cure only a portion of the photocurable resin film that is to be image-patterned and removing an uncured portion by development is mentioned.

The image pattern constituting the display panel of the present invention is obtained by exposing and developing the photopolymerizable resin composition film as described above. The light source for exposing is not particularly limited. However, a well-known one can be used, and, for example, an ultra-high pressure mercury lamp, a metal halide lamp, or the like is preferably used. The developing solution used for development is not particularly limited, but for example, an aqueous solution of sodium carbonate having a concentration of 0.5 to 5% by weight is preferably used. The developing device is not particularly limited, and a known device can be used.

[0036]

EXAMPLES The present invention will be described below based on examples.

(Example 1) [Preparation of unsaturated compound capable of photopolymerization] Hexamethylene diisocyanate 504 g (3 mol) was placed in a 5-liter four-necked flask equipped with a reflux condenser, a dropping funnel, a thermometer and a mechanical stirrer. And 826 g of dry methyl ethyl ketone (MEK) and 1 g of dibutyltin dilaurate (catalyst) as a solvent are added, and 916 g of polyethylene glycol (2 mol, average molecular weight: 458) while stirring.
Was added and the mixture was refluxed for 5 hours.

Then, 232 g (2 mol) of 2-hydroxyethyl acrylate was added dropwise, the mixture was refluxed for another 5 hours for reaction, and MEK was evaporated to prepare a photopolymerizable unsaturated compound.

[Preparation of Photopolymerizable Resin Composition] 100 parts by weight of linear copolymer (methyl methacrylate / butyl methacrylate / methacrylic acid = weight ratio 50/25/25, weight average molecular weight Mw = 150,000) Polymerizable unsaturated compound 75 parts by weight Photopolymerizable monomer (component: tetraethylene glycol 75 parts by weight diacrylate) Photopolymerization initiator (component: benzyl dimethyl ketal) 2.5 parts by weight (“Irgacure” manufactured by Ciba Geigy) 651 ") The above substance was dissolved in 250 parts by weight of MEK to prepare a solution of the photopolymerizable resin composition.

[Preparation of Photocurable Resin Film] A solution of the photopolymerizable resin composition was cast on a PET film having a thickness of 75 μm, dried at 80 ° C. for 10 minutes, and then dried. A 100 μm photocurable resin film was produced.

[Production of Stereoscopic Image Display Panel] The PET film 3 of the photocurable resin film 1 was peeled off to give a thickness of 500 μm.
The work of laminating by a thermal laminating method on the polycarbonate substrate 2 of m is repeated 4 times to laminate the four layers of the photocurable resin film 1, and then the photocuring with the PET film 3 as the uppermost layer. Resin film 1 with PET
The film 3 was laminated so that the film 3 was on the upper side to prepare a laminate 4 (total thickness of the photocurable resin film of 500 μm) including the five layers of the photocurable resin film 1.

Then, as shown in FIG. 1, a photomask 5 which allows light to pass through only the portions corresponding to the characters and the scale is placed on the photocurable resin film 1 of the laminate 4 and 1000 mJ / cm by a 3 KW ultra-high pressure mercury lamp. Ultraviolet rays 6 having an intensity of ² were irradiated.

The laminate 4 of the photocurable resin film 1 is exposed and cured by irradiation with ultraviolet rays 6, and then the laminate 4 is formed.
The exposed surface of No. 1 was developed with a 1% sodium carbonate aqueous solution at 30 ° C., and as shown in FIG. 2, a display panel 8 having a three-dimensional image 7 was obtained in which portions corresponding to characters and scales became convex.

[Bending test] The obtained display board 7 was
When the peeled state was observed by winding it around a mm round bar, peeling was not seen in the three-dimensional image 6 corresponding to the characters and the scale, showing good adhesion.

(Examples 2 to 3, Comparative Example 1) With the composition shown in Table 1, a photopolymerizable unsaturated compound was prepared in the same manner as in Example 1, and then a linear copolymer was prepared. An unsaturated compound, a photopolymerizable monomer and a photopolymerization initiator shown in 1 were added to obtain a photopolymerizable resin composition. From the photopolymerizable resin composition,
A photocurable film was prepared in the same manner as in Example 1, and then exposed and cured to prepare a display board having a stereoscopic image.

A bending test was conducted on the obtained display panel in the same manner as in Example 1, and the results are shown in Table 2.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

EFFECTS OF THE INVENTION According to the method for producing a stereoscopic image display panel of the present invention, two or more layers of a photocurable resin film made of a specific photopolymerizable resin composition are laminated on a base material, and exposed and cured. As a result, a three-dimensional image is formed, so that the obtained image has excellent adhesion to the substrate and further has flexibility.
It has excellent durability and does not peel off due to bending.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a state of exposing a photocurable resin film used in an example of the present invention.

FIG. 2 is a schematic cross-sectional view showing a stereoscopic image formed by exposing and curing a photocurable resin film used in Examples of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photocurable resin film 2 Base material 3 PET film 4 Laminated body 5 Photomask 6 Ultraviolet light 7 Stereo image 8 Display board

Claims (1)

[Claims] 1. A photocurable resin film is laminated on a substrate,
A method for manufacturing a display panel, which comprises exposing a film through a mask and curing it, and removing an uncured portion to form a predetermined image pattern, wherein the photocurable resin film comprises (a) a carboxyl group-containing α, β- A linear copolymer having a weight average molecular weight of 20,000 to 500,000, which comprises 10 to 40% by weight of an unsaturated ethylenic monomer and 60 to 90% by weight of an α, β-unsaturated ethylenic monomer other than the above-mentioned components. 100 parts by weight of polymer (b) 5-150 parts by weight of at least one photopolymerizable unsaturated compound selected from the group consisting of compounds represented by the following general formula (I): (In the formula, R ¹ and R ² are hydrogen groups or methyl groups, and n is 1 to
An integer of up to 15, R ³ is a hydrocarbon group having 1 to 10 carbon atoms, m is an integer of 1 to 100, and X is a divalent hydrocarbon group having 2 to 20 carbon atoms. (C) Photopolymerization initiator sensitized by actinic rays 0.1 to 1
A photopolymerizable resin composition consisting of 0 parts by weight is used as a component, and two or more layers of this photocurable resin film are laminated on a substrate to give 0.15
A method for producing a three-dimensional image display panel, which has a thickness of 2.5 mm, is exposed and cured to form an image pattern.