JP4587674B2 - Method for forming phosphorescent coating - Google Patents

Description

  The present invention relates to a method for forming a phosphorescent coating film using an active energy ray-curable coating material.

  Phosphorescent paints are used for painting evacuation guidance signs for ships, buildings, underground malls, fishing gear, hobby equipment, accessories, alarm clocks, etc. The special function that shines in the dark has been heavily used for many years. Conventionally, as a method for increasing the luminance of a phosphorescent paint, a method of applying a solvent-type white paint and then applying a solvent-based phosphorescent paint (see Patent Documents 1 to 3) is known. In any case of factory painting, it took a lot of time to dry the paint, or a special heat drying device was required. In addition, the use of organic solvents has problems such as bad odor, health hazard, and fire.

Thus, considering health and safety, it is possible to make the paint water-based, but there is a problem that the drying time of the coating film becomes longer than that of the solvent-based paint.
JP-A-10-82023 JP-A-10-88025 Japanese Patent Laid-Open No. 10-88031 JP 7-11250 A

  As described above, all the conventional methods for applying the phosphorescent paint have problems, and no definitive method has been found yet. An object of the present invention is to perform painting in a short time without requiring odor / safety measures and without using a special heating and drying apparatus.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have applied a solvent-free active energy ray-curable white paint and then a solvent-free active energy ray-curable transparent paint containing a phosphorescent pigment. The present invention has been completed by finding that the above-mentioned problems can be solved by coating the film.

That is, the method for forming a phosphorescent coating film of the present invention comprises applying a primer coating composed of a solventless active energy ray-curable resin, a photopolymerization initiator and a white pigment, and irradiating the active energy ray to form a half-coated coating film. After forming in a cured state, it consists of a solventless active energy ray curable resin, a photopolymerization initiator and a phosphorescent pigment, and the weight ratio of the active energy ray curable resin / phosphorescent pigment is 100/50 to 100/400 It is characterized in that a certain top coating material is applied and the active energy ray is irradiated to cure the top coating film.

  The method of forming a coating film of the present invention is to apply an undercoat paint composed of a solventless active energy ray-curable resin, a photopolymerization initiator and a white pigment, and after irradiating active energy rays to form an undercoat film, A top coating composition comprising a solventless active energy ray curable resin, a photopolymerization initiator, and a phosphorescent pigment, wherein the weight ratio of the active energy ray curable resin / phosphorescent pigment is 100/50 to 100/400 is applied and activated. By irradiating energy rays and curing the top coat film, it was possible to form a luminous film having excellent adhesion. That is, according to the present invention, it is possible to carry out painting work in a short time even in poorly ventilated indoors such as buildings, underground malls, subways, etc. Further, by using no organic solvent or water, unpleasant odor emission and health problems are prevented. In addition to eliminating the danger of fire, there is no fire caused by ignition, so there is an advantage that construction can be done with peace of mind. Even when the present invention is applied to line coating, energy consumption during drying is reduced and the process is shortened, so the productivity jumps. Improvement.

  The present invention is described in detail below.

  Specific examples of the solventless active energy ray-curable resin used in the undercoat and topcoat of the present invention include relatively low molecular weight polyester resins, alkyd resins, polyether resins, acrylic resins, epoxy resins, urethanes. Resin, silicone resin, polybutadiene resin (meth) acrylate oligomer or prepolymer, and 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dipropylene glycol mono (meta ) Acrylate, (meth) acrylamide, N-vinylpyrrolidone, triethylene glycol di (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaeri Ritoruhekisa (meth) acrylate and their polymers, oligomers, monomers ethylene oxide, either alone or a mixture of reactive monomers such as propylene oxide-modified products thereof as representative.

  Further, as the active energy ray curable resin, ion polymerization type vinyl-2-ethylhexyl ether, vinyl decyl ether, 1,2-epoxycyclohexane, dicyclopentadiene dioxide, sorbitol polyglycidyl ether and the like can be used.

As the photopolymerization initiator used in the undercoat paint and the topcoat paint of the present invention, a radical polymerization type and an ion reaction type are conventionally known, and various known photopolymerization initiators can be used. Specifically, in the radical polymerization type, sulfides such as sodium methyldithiocarbamate sulfide, diphenyl monosulfide, dibenzothiazoyl monosulfide and disulfide; thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-diethyl Thioxanthone derivatives such as thioxanthone; azo compounds such as hydrazone and azobisisobutyronitrile; diazo compounds such as benzenediazonium salt; benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, dimethylaminobenzophenone, Michler's ketone, benzylanthraquinone, t- Butylanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-aminoanthraquinone, 2-chloroanthra Aromatic carbonyl compounds such as non; dialkylaminobenzoates such as methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, butyl p-dimethylaminobenzoate, isopropyl p-diethylaminobenzoate; benzoyl peroxide; Peroxides such as di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide; acridine derivatives such as 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine, benzacridine; 9 1, 10-dimethylbenzphenazine, 9-methylbenzphenazine, phenazine derivatives such as 10-methoxybenzphenazine; quinoxaline derivatives such as 6,4 ′, 4 ″ -trimethoxy-2,3-diphenylquinoxaline; Hydroxyacetophenones such as nyl-2-hydroxy-2-methylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, diethoxyphosphine oxide, bis (2,4 , 6-Trimethylbenzoyl) -phenylphosphine oxide and the like (bis) acylphosphine oxides; bis (η ⁵ -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H) -Pyrrol-1-yl) -phenyl) titanium derivatives such as titanium; 2,4,5-triphenylimidazolyl dimer, 2-nitrofluorene, 2,4,6-triphenylpyrylium tetrafluoroborate salt 2,4,6-tris (trichloromethyl) -1,3,5-triazine, , 3′-carbonylbiscoumarin, thiomihilerketone, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone, 2-benzyl-2-dimethylamino-1- ( 4-morpholinophenyl) -butanone and the like. On the other hand, the ionic polymerization type specifically includes allyldiazonium boron fluoride.

The top coating composition of the present invention contains a photoluminescent pigment that is excited by ultraviolet rays, particularly light of 360 nm or less, and therefore it is preferable to select a photopolymerization initiator that has absorption at 360 nm or more and is excited. Specifically, benzoin ethyl ether, 4,4′-bis (dimethylamino) benzophenone, 1-hydroxycyclohexyl phenyl ketone, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl ) Propanone, 2,4,6-trimethylbenzoin diphenylphosphine oxide, diethoxyphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (η ⁵ -2,4-cyclopentadiene -1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium and the like can be selected.

  The undercoat and topcoat of the present invention may contain various additives such as extender pigments, polymerization inhibitors, curing catalysts, antioxidants, dispersants, leveling agents, and silane coupling agents, if necessary.

  Examples of extender pigments used in the undercoat and topcoat of the present invention include silica sand, silicate, talc, kaolin, barium sulfate, calcium carbonate, powder, flake or fiber glass, polyurethane, polyester, polyethylene, polystyrene, and the like. Typical examples of the resin powder are as follows.

  As the white pigment used in the undercoat paint of the present invention, a white pigment used for a normal paint can be used without any particular limitation.

  Examples of the white pigment used in the present invention include titanium oxide, zinc oxide, and zinc sulfide.

  The phosphorescent pigment used in the top coating composition of the present invention is not particularly limited as long as it is a phosphorescent pigment having an afterglow. For example, a sulfide-based phosphorescent pigment, an oxyacid salt-based phosphorescent pigment, an alumina oxide-based phosphorescent pigment, or the like. included. Examples of sulfide-based phosphorescent pigments include calcium sulfide: bismuth (CaS: Bi), calcium sulfide / strontium: bismuth (CaSrS: Bi), zinc sulfide: copper (ZnS: Cu), and zinc sulfide / cadmium: Examples thereof include copper-based (ZnCdS: Cu).

Examples of the alumina oxide phosphorescent pigment include aluminum oxide / calcium: europium (CaAl ₂ O ₄ : Eu), aluminum oxide / strontium: europium (SrAl ₂ O ₄ : Eu), aluminum oxide / barium: europium (BaAl ₂ O ₄ : Eu) and the like are included. The alumina oxide phosphorescent pigment includes the phosphorescent phosphor disclosed in Patent Document 4. As disclosed in Patent Document 4, when europium is used as an activator and a rare earth element such as terbium or dysprosium is used as a coactivator, a phosphorescent pigment having a long afterglow time is obtained. More specifically, the product name “N Yakko Luminova” manufactured by Nemoto Special Science Co., Ltd. can be suitably used as the alumina oxide phosphorescent pigment. The phosphorescent pigments can be used alone or in combination of two or more.

  The phosphorescent pigment is composed of a metal compound and a rare earth element as described above, and is adjusted as a ceramic by mixing and firing the metal compound and the rare earth element. The average particle diameter of the phosphorescent pigment is not particularly limited, and is, for example, about 0.1 to 50 μm, preferably about 0.5 to 30 μm. When the average particle size is too small, the afterglow characteristics are deteriorated. On the other hand, if it is too large, separation of the pigment component is likely to occur, the coloring property of the phosphorescent pigment is lowered, and furthermore the roughness of the coating film surface becomes excessive, so that the appearance is impaired, and the phosphorescent pigment from the coating film There is a possibility of causing dropout of particles, which is not preferable.

  The undercoat paint used in the present invention comprises the above-described active energy ray-curable resin, photopolymerization initiator, and white pigment.

  The mixing ratio of these components is 0.1 to 20 parts by weight, preferably 1.0 to 15.0 parts by weight of the photopolymerization initiator with respect to 100 parts by weight of the active energy ray-curable resin. . If the amount is less than 0.1 parts by weight, the polymerization rate tends to be slow, and it tends to require long-time light irradiation in order to satisfy hardness and scratch resistance, and sometimes tends to be uncured. On the other hand, when it is added in an amount exceeding 20 parts by weight, the flexibility of the coating film is lowered, and functions such as wear resistance and weather resistance are liable to be lowered. The white pigment is added in an amount of 10 to 60 parts by weight, preferably 15 to 50 parts by weight, with respect to 100 parts by weight of the active energy ray-curable resin and the photopolymerization initiator. If it is less than 10 parts by weight, the concealability of the coating film is lowered, and the light emission of the top coating material containing the phosphorescent pigment tends to be unclear. On the other hand, when it is added in an amount exceeding 60 parts by weight, the transmission of active energy rays into the undercoat paint becomes insufficient, and the undercoat paint needs to be irradiated with light for a long time and sometimes uncured.

  In the present invention, it is preferable that the coating film formed by irradiating active energy rays after applying the undercoat paint is in a semi-cured state. Subsequently, the top coating composition of the present invention is applied, the active energy ray is applied again, and the top coating film is cured. At this time, the transmittance of ultraviolet / visible light having a wavelength of 360 nm to 700 nm is 3 If it is at least%, the undercoat film in a semi-cured state is easily cured at the same time. Therefore, there is a tendency that a multilayer coating film having extremely good interlayer adhesion between the undercoat film and the top coat film is formed.

  The top coating used in the present invention comprises the above-described active energy ray-curable resin, photopolymerization initiator, and phosphorescent pigment.

  The blending ratio of these components is 0.1 to 20 parts by weight, preferably 1.0 to 15.0 parts by weight of the photopolymerization initiator with respect to 100 parts by weight of the active energy ray-curable resin. If it is less than 0.1 parts by weight, photopolymerization is slow, and it tends to require long-time light irradiation for curing the coating film, and sometimes tends to be uncured. On the other hand, when it is added in excess of 20 parts by weight, the physical properties of the coating film become brittle and functions such as wear resistance and weather resistance are liable to deteriorate. The phosphorescent pigment is added in an amount of 50 to 400 parts by weight, preferably 80 to 300 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin and the photopolymerization initiator. If it is less than 50 weight part, the afterglow brightness | luminance of a coating film will fall easily. On the other hand, if it is added in excess of 400 parts by weight, the physical properties of the top coating become brittle, the smoothness of the coating film becomes poor, and the fluidity of the coating is remarkably lowered, which hinders the painting operation.

  The top coat used in the present invention preferably has a transmittance of 3% or more of ultraviolet and visible light having a wavelength of 360 nm or more and 700 nm or less of the coating film. If the transmittance is lower than 3%, the semi-cured undercoat film is cured at all or very little upon irradiation with active energy rays after the top coat, and may be separated between layers.

  The top coating used in the present invention contains a coloring pigment in an amount that does not significantly impede the light absorption and emission of the phosphorescent pigment in the composition and that can maintain an ultraviolet / visible light transmittance of 3% or more. Is preferred.

  Color pigments include titanium oxide, zinc sulfide, zinc white, lead white, lithopone, carbon black, oil smoke, bitumen, phthalocyanine blue, ultramarine, carmine FB, yellow lead, zinc yellow, Hansa yellow, ocher, bengara, insoluble metal-containing metal Representative examples include azo dyes. In addition, fluorescent pigments can also be used. The organic fluorescent pigment is obtained by forming a solid solution of an organic fluorescent dye such as Basic Violet 10, 11 or Basic Yellow HG, Rhodamine 6G, or B in a synthetic resin and pulverizing it to a particle size of 0.1 to several tens of μm. And trade names FZ, FR, FA series manufactured by Shinroihi Co., Ltd., and the like.

  Arbitrary methods can be adopted for adjusting the undercoat and topcoat of the present invention, but the active energy ray-curable resin alone, or a part of the mixed solution, a pigment and, if necessary, a thermal polymerization inhibitor, Add additives such as wetting agent, dispersing agent, antifoaming agent, and disperse with dispersers such as paint shaker, ball mill, sand mill, triple roll, attritor, homomixer, etc., and the remaining active energy ray curable resin A method in which a photopolymerization initiator and various additives as required are added and dissolved uniformly is suitable.

  As the method for applying or printing the undercoat and topcoat of the present invention, conventional methods such as brush coating, spray coating, roller coating, spin coating, roll coating, barcode, doctor blade, dipping, screen printing, etc. Can be done.

As an irradiation apparatus for active energy rays used in the present invention, an ultraviolet light source such as a low pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a xenon lamp, an excimer laser, or a dye laser can be used. The amount of irradiation is suitably in the range of 50 to 3000 mJ / cm ^{2 in} the case of ultraviolet rays. In general, the film thickness of the undercoat paint is preferably in the range of 10 to 100 μm, and the film thickness of the overcoat paint is generally preferably in the range of 50 to 500 μm.

  The phosphorescent coating film formed by the paint of the present invention can be applied in various fields including iron, concrete structures, building materials, roads, ships, airplanes, vehicles, electrical equipment and electronic equipment, and as a specific base material In addition, metals, synthetic resins, glass, ceramics, wood, paper, and the like are listed as applicable targets.

  Specific examples include road tunnels, subways, various signs for railway vehicles, emergency stairs such as underground malls and buildings, road evacuation guidance signs, digesters, fire hydrant marks, signs, and the like.

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the examples and comparative examples.
<Undercoating paint A>
Epoxy acrylate oligomer (trade name “Lipoxy SP-1509” manufactured by Showa Polymer Co., Ltd.); 60 parts, N-vinylpyrrolidone; 20 parts, triethylene glycol diacrylate; 20 parts, rutile titanium oxide (product of Sakai Chemical Industry Co., Ltd.) Name “R-5N”); 40 parts were mixed using a stirrer and then kneaded with a sand mill to obtain a mill base. The crushing of the mill base according to JIS-K-5600 2-5 dispersity distribution method was 25 μm. Next, 5 parts of bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; 5 parts was added to the mill base and stirred uniformly to prepare a white undercoat paint A.

<Undercoating paint B>
Using an agitator, 60 parts of ethoxylated trimethylolpropane triacrylate, N-vinylpyrrolidone; 20 parts, triethylene glycol diacrylate; 20 parts, and 25 parts of zinc flower (trade name “Zinc Flower No. 1” manufactured by Sakai Chemical Industry Co., Ltd.) And mixed with a sand mill to obtain a mill base. The crushing of the mill base according to JIS-K-5600 2-5 dispersity distribution method was 25 μm. Next, 5 parts of bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; 5 parts was added to the mill base and stirred uniformly to prepare a white undercoat paint B.

<Undercoating paint C>
White solvent paint "Mighty Epo Sealer White" (trade name, manufactured by Dainippon Paint Co., Ltd.)

<Topcoat a with phosphorescent pigment>
Urethane acrylate oligomer (Nippon Gosei Co., Ltd., trade name “purple light UV7000B”); 30 parts, 2-hydroxyethyl methacrylate; 55 parts, dipropylene glycol monoacrylate; 15 parts, phosphorescent pigment (trade name, manufactured by Nemoto Special Chemical Co., Ltd., N Nightlight Luminova GLL-300F); 50 parts, talc powder (trade name: Simgon, manufactured by Nippon Talc Co., Ltd.); 10 parts were mixed, and then kneaded in a sand mill. The crushing according to the distribution diagram of the mill base JIS-K-5600 2-5 dispersity was 60 μm. Next, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide; 3 parts, 2-hydroxy-2-methyl-1-phenyl-propan-1-one; 2 parts are added to the mill base and stirred until uniform. Then, the top coat a was prepared.

<Topcoat b, c, d, e, f, g with phosphorescent pigment>
Thereafter, the top coating materials b, c, d, e, f, and g were prepared by the same adjustment method as that for the top coating material a and with the composition described in Table 1 of the attached sheet.

<Solvent paint with phosphorescent pigment h>
"Combination Luminous Paint" (trade name made by Sinloihi)

(Example 1)
After applying the white undercoat paint A to the concrete substrate with a brush, it was irradiated with ultraviolet rays (distance 15 cm, irradiation for 1 second) with a handy type ultraviolet irradiator (1 KW mercury lamp). In this state, the top coat a was applied with a brush and then irradiated with the ultraviolet irradiator (distance 15 cm, irradiation for 3 seconds). Table 1 shows the properties and performance test results of the obtained coating films.

(Example 2)
In Example 1, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 1 except that b was used for the top coat. The results are shown in Table 1.

(Example 3)
In Example 1, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 1 except that c was used for the top coat. The results are shown in Table 1.

Example 4
In Example 1, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 1 except that B was used for the undercoat paint and d was used for the topcoat paint. The results are shown in Table 1.

(Example 5)
In Example 4, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 1 except that e was used for the top coat. The results are shown in Table 1.

(Comparative Example 1)
In Example 1, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 1 except that f was used for the top coat. The results are shown in Table 1.

(Comparative Example 2)
In Example 4, a multilayer coating film was prepared and performance was evaluated in the same manner as in Example 4 except that g was used for the top coat. The results are shown in Table 1.

(Comparative Example 3)
The undercoat paint C was applied to the same concrete base material as in Example 1 with a brush, and then dried at room temperature for 24 hours. Next, the top coat h was applied with a brush to obtain a multilayer coating film. For this comparative example, the room temperature drying paint was dried for 1 week in a room temperature environment and subjected to the test. Table 1 shows the properties and test results of the obtained coating films.

Note 1) Product name made by Nippon Synthetic Chemical Company
Note 2) Product name manufactured by Nemoto Special Chemical Co., Ltd. N Yoko Luminova GLL-300F
Note 3) Product name manufactured by Dainichi Seika Kogyo Co., Ltd. Phthalocyanine Blue 5030S
Note 4) Product name made by Nippon Talc Co., Ltd. Simgon Note 5) Product name made by Tatsumori Company AA
Note 6) Product name made by Sinloihi Co., Ltd. Sinroihi color FZ6037
Note 7) Lucirin TPO
Note 8) DAROCUR 1173

  Each item in Table 1 was evaluated and measured according to the following method.

<Adhesiveness>
Conforms to JIS-K-5600-5-6 adhesion test method. A 25 mm square cut test was conducted, the peeled state was confirmed with an adhesive tape (trade name: cellophane tape), and the remaining number in 25 was displayed.

<Balance brightness>
Compliant with JIS-Z-9107 safety sign board phosphorescence luminance test method. The values in Table 2 were used as a reference.

<Odor test>
Conforms to JIS-K-1901. A coating plate immediately after painting (undercoat A, B, and top coats a, b, c, d, e, f, and g after irradiation with active energy rays) is applied on the inner surface of a dedicated chamber of 300 × 300 × 300 mm with a load factor of 2.2. The chamber was ventilated with clean air so that the ventilation rate was 0.5. The odor of the gas in the chamber 1 hour after the start of the test was evaluated by a sensory test.

  ○: No odor. Or just not to worry.

  Δ: Slight organic solvent odor

  ×: Strong organic solvent odor, irritation of nose, throat and eyes.

  The luminance at regular intervals was measured with a color luminance meter (BM-5A manufactured by Topcon Corporation).

  From Table 1, the ratio of active energy ray-curable resin / phosphorescent pigment was set to 100/50, 100/150, and 100/300. Each of Examples 1, 2, and 3 satisfies the phosphorescence luminance standard of the phosphorescent sign board in the safety sign board specified in the above JIS-K-9107, but Comparative Example 1 having the same ratio 100/35 is Comparative Example 2, which is lower than the above JIS standard and has the same ratio of 100/450, satisfies the above JIS standard, but has too much pigment, so that the fluidity of the paint is poor and the adhesion of the coating film is also poor.

  Example 4 is an example when phthalocyanine blue is used in combination as a color pigment, and a fluorescent blue color in which phosphorescence from a phosphorescent pigment and a non-fluorescent pigment blue color are mixed is obtained. Example 5 was obtained by adding a pink color of a fluorescent pigment in addition to a phosphorescent pigment, and a nocturnal paint that emits a very clear fluorescent color was obtained.

  Comparative Example 3 is a case where a solvent-type undercoat paint and the same topcoat paint containing a phosphorescent pigment were used. Compared to the Examples, the coating interval was longer, and the organic solvent odor was strong in the odor test. .

Claims (4)

After applying an undercoat paint consisting of a solventless active energy ray-curable resin, a photopolymerization initiator, and a white pigment, and irradiating active energy rays to form an undercoat film in a semi-cured state, a solventless active energy It consists of a line curable resin, a photopolymerization initiator and a phosphorescent pigment, and is coated with a top coat having a weight ratio of the active energy ray curable resin / phosphorescent pigment of 100/50 to 100/400 and irradiated with active energy rays. A method for forming a phosphorescent coating film, characterized by curing the top coat film. The method for forming a phosphorescent coating film according to claim 1, wherein the photopolymerization initiator is a photopolymerization initiator that is absorbed and excited by light having a wavelength of 360 nm or more.   The method for forming a phosphorescent coating film according to claim 1, wherein the top coating contains a color pigment.   The method of forming a phosphorescent coating film according to any one of claims 1 to 3, wherein the top coating film has an ultraviolet / visible light transmittance of 3% or more at a wavelength of 360 nm or more and 700 nm or less.