JPH1028929A - Light-accumulating fluorescent powder coating material and coating method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reaction of a light-accumulating fluorescent substance with heavy metals and to avoid decrease in afterglow performance by mixing light-accumulating fluorescent particles with powder particles comprising a resin component of a binder preliminarily prepared while maintaining the particle size of particles and then incorporating the mixture into a coating material. SOLUTION: The coating material contains a mixture prepared by mixing light-accumulating fluorescent particles with a powder coating material comprising a resin component of a binder preliminarily prepared while maintaining the grain size of the particles. The light-accumulating fluorescent substance is a compd. obtd. from an oxide compd. expressed by MAl2 O4 as the mother crystal, or a magnesium-added oxide compd. prepared from the oxide compd. above described with addition of magnesium as the mother crystal, or an activated phosphor compd. prepared by adding europium by 0.001 to 10mol% of te element M to the oxide compd. or the magnesium-added oxide compd. above described. The element M is selected from calcium, strontium and barium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphorescent phosphor powder coating which does not impair the performance of a phosphorescent phosphor and a method of coating the same.

[0002]

2. Description of the Related Art So-called luminous phosphors or phosphors are known in which afterglow is observed, for example, for several tens of minutes to several hours, even after the irradiation is stopped by irradiation with ultraviolet rays or the like. When the irradiation of the irradiation light is stopped, the intensity of light emission is rapidly attenuated, and the afterglow time is extremely short, which is distinguished from a so-called phosphor.

For a long time, metal sulfides have been known as phosphorescent phosphors. Specifically, for example, CaS: Bi (purple blue emission), CaSrS: Bi (blue emission), ZnS:
Examples thereof include Cu (green light emission) and ZnCdS: Cu (yellow to orange light emission), which are used for luminous clocks, evacuation guidance signs, and other nighttime displays for indoor use. In addition, these sulfide phosphors have problems in chemical stability and light resistance, and decrease in luminance due to black change due to ultraviolet decomposition under moisture, etc., have a limited range of use. Since the afterglow time which can be visually recognized is as short as about 30 minutes to 2 hours, as a phosphorescent phosphor having improved these problems, for example, as described in JP-A-7-11250, MAl ₂ O ₄ ( In the formula, M is at least one selected from the group consisting of calcium, strontium, and barium.) A compound in which a compound represented by the following formula is used as a mother crystal or a modified product thereof is also known. Has been noted.

[0004]

However, this M
Al ₂ O ₄ and its modified products have a problem that when they come into contact with heavy metals such as iron, the structure is changed and the brightness is reduced. On the other hand, the particle size of the phosphorescent phosphor has a large relationship with the afterglow performance. However, there is also a problem that the afterglow performance is deteriorated when the particles are broken down into fine particles, and when a powder coating using the phosphorescent phosphor as a pigment is manufactured by a general mechanical pulverizing method as in the past, These problems cannot be avoided. That is, a general method for producing a powder coating is that raw materials such as a pigment, a resin for a binder, a curing agent, and a spreading agent are premixed with a stirrer, and the mixture is heated and melted using an extruder and kneaded at a high temperature. The pigments are dispersed in a resin or the like by combining them, then coarsely pulverized, and the coarsely pulverized material is further pulverized by a pulverizer such as a pin mill, and the powder particles are classified by a cyclone, a sieve or the like to obtain a product. When trying to produce a powder coating using a phosphorescent phosphor as a pigment by the manufacturing method, the phosphorescent phosphor comes into contact with strong pressure and high temperature at a high pressure and high temperature with iron metal and the like constituting the inner wall of the extruder cylinder. The metal reacts with the phosphorescent phosphor to transform into a compound that reduces afterglow. On the other hand, when coarsely pulverized by a pulverizer, the phosphorescent phosphor is finely pulverized and remarkably loses its afterglow, so that a powder coating having a phosphorescent phosphor having strong persistence cannot be obtained. The coating using the phosphorescent phosphor as a pigment can be performed by a liquid paint obtained by dispersing the phosphorescent phosphor in a liquid vehicle. It cannot be as thick as several hundred μm.

A first object of the present invention is to provide a luminous phosphor powder coating material and a method of coating the luminous phosphor, which does not react with heavy metals and does not impair the afterglow performance. Things. A second object of the present invention is to provide a luminous phosphor powder coating material in which the luminous phosphor maintains its particle size so as not to impair the afterglow performance, and a method of applying the same. A third object of the present invention is that the film thickness is sufficiently large,
An object of the present invention is to provide a luminous phosphor powder coating material and a method for coating the luminous phosphor powder that can clearly display a luminous phosphor. A fourth object of the present invention is to provide a coating method in which the display by the phosphorescent phosphor is clearly performed even when the ground color of the object to be coated is exposed.

[0006]

In order to solve the above-mentioned problems, the present invention provides (1) a powder coating containing a luminous phosphor and a binder, wherein at least a resin component of the binder prepared in advance. And a phosphorescent phosphor powder coating containing a mixture of the phosphorescent phosphor particles and a mixture of the phosphorescent phosphor particles while maintaining their respective particle sizes. In the present invention, (2) the phosphorescent phosphor is represented by the general formula M
A compound in which an oxide compound represented by Al ₂ O ₄ (wherein M is at least one selected from the group consisting of calcium, strontium and barium) as a mother crystal, Magnesium-added oxide-based compounds in which a magnesium-added compound is used as a mother crystal, or europium as an activator for these oxide-based compounds or magnesium-added oxide-based compounds, in an amount of 0.001% to 0.001% by mol based on M The phosphorescent phosphor powder coating material of the above (1), which is an activated phosphor compound added by 10%;
(3) the phosphorescent phosphor powder coating material according to (1) or (2), wherein the resin component is a thermosetting resin or a thermoplastic resin;
(4) A step of forming a base film having high brightness without thermal yellowing on the object to be coated, a step of heating the base film, and a step of heating the base film. And a method for applying the phosphorescent phosphor powder coating material. Note that, in the above (1), in the method for producing a powder coating containing a phosphorescent phosphor and a binder, a step of preparing a powder coating comprising at least a resin component of the binder; A method of producing a mixture in which the phosphorescent phosphor particles are mixed while maintaining their respective particle sizes, and a method of producing a phosphorescent phosphor powder coating for producing a phosphorescent phosphor powder coating containing the mixture. In the above inventions, the “powder coating composed of at least the resin component of the binder” may be replaced with the “powder coating composed of the binder”. ].

In the present invention, “a mixture mixed while maintaining the respective particle sizes” means “a powder coating composed of at least a resin component of the binder prepared in advance”.
The phosphorescent phosphor particles are a mixture obtained by performing a premixing (simple mixing using a stirring blade) with a stirrer or mixing without performing the premixing by a dry blending method. Dry red method is a mixing method in which objects to be mixed are mainly mixed in the process of floating in the air,
This is a mixing method that does not make strong contact with the wall surface or exert a large shearing force on an object to be mixed. Examples of the stirrer used in such a mixing method include a V-type mixer and a ribbon blender. The former is to insert the material to be mixed from the upper ends of both ends of the V-shaped cylinder, cover it, and then rotate it vertically.The ribbon blender rotates the spiral ribbon inside the cylinder to mix. The materials are mixed while being advanced in the axial direction. These stirrers crush phosphorescent phosphor particles by applying a shearing force, as in the above-described extruder for producing a general powder coating, and the energy is used to pulverize the phosphorescent phosphor particles to reduce the particle size. In addition to reducing the size, the metal that is a constituent material of the vessel wall and the phosphorescent phosphor particles collide strongly, and the phosphorescent phosphor particles react with the metal to change into a substance that reduces the persistence On the contrary, it is designed such that the crushing power for the phosphorescent phosphor particles is weak and the reactivity with the metal is low. In this sense, the “mixture mixed while maintaining the respective particle sizes” is added to the “prepared powder coating composed of at least the resin component of the binder” and the (almost) sheared phosphorescent phosphor particles. With no force applied, the collision of these particles with the (metal) vessel wall of the mixer is weak (to the extent that the phosphorescent phosphor particles do not react with the metal of the vessel wall) and their respective particle sizes are reduced. A mixture maintained and mixed "may be used.

In the present invention, the resin component of the binder is not melted as described above, but the powder particles are simply mixed with the phosphorescent phosphor particles. Since it is different from the general method of producing a powder coating by further pulverizing the dispersion in which the phosphor particles are dispersed, so that the pulverization is not necessary, the "powder coating comprising at least the resin component of the binder" The “phosphorescent phosphor particles” must be sized beforehand except for coarse particles. It is preferable to use those which have passed through a sieve of 70 mesh, preferably 100 to 150 mesh. The above-mentioned “step of producing a mixture in which the powder coating particles and the luminous phosphor particles are mixed while maintaining their respective particle sizes” is referred to as “classifying the powder coating particles and the luminous phosphor particles ( A step of producing a mixture in which the mixture is classified while passing through a sieve having a size of 100 to 150 mesh) while maintaining the respective particle sizes.

In the present invention, the phosphorescent phosphor is
The ones mentioned in the above section of "Prior Art", in particular,
An oxide described in JP-A-11250 is preferable, but an oxide represented by the general formula MAl ₂ O ₄ (where M is at least one selected from the group consisting of calcium, strontium and barium). A compound in which a base compound is used as a mother crystal, a magnesium-added oxide compound in which a compound obtained by adding magnesium to this oxide-based compound is used as a mother crystal, or activation of these oxide-based compounds or magnesium-added oxide-based compounds Activated phosphor compounds in which europium is added in an amount of 0.001% to 10% by mole based on M as an agent are exemplified. At this time, lanthanum, cerium, praseodymium, neodymium, samarium, gadolinium, terbium, dysprosium,
Homamium, erbium, thulium, ytterbium,
At least one element of the group consisting of lutetium, manganese, tin, and bismuth in an amount of 0.0
It is also preferable to add from 01% to 10%. Among these phosphorescent phosphors, it is also preferred that when irradiating ultraviolet light and visible light of 200 to 450 nm at room temperature, it has a glow peak of thermoluminescence in a high temperature region of at least 50 ° C or more. Specifically, Nekko Special Chemical Co., Ltd. N night light DP-
007 and the like.

The average particle diameter (μm) of the phosphorescent phosphor and the relative value of the afterglow luminance (%) (the phosphorescent phosphor N is sieved to determine the relative luminance based on the persistence luminance of the average particle diameter of 60 μm). value)
Dependence of afterglow luminance on the particle size (irradiation condition: excitation with a common light source D ₆₅ , illuminance of 400 Lx for 20 minutes, measurement condition: 22 ± 10 ° C., measured value of afterglow luminance after 30 minutes)
Is shown, for example, in FIG. The average particle size of the luminous phosphor is obtained by producing the luminous phosphor and classifying it with a sieve or the like.

As the powder coating used in the present invention, either a thermoplastic powder coating or a thermosetting powder coating can be used. The powder coating contains a binder, and the binder has at least a resin component. If necessary, additives such as a plasticizer, a coloring agent (including a dye or a pigment), a spreading agent, and an anti-yellowing agent are used. And kneaded into a powder. When a colorless and transparent clear paint excluding the pigment is used as the powder paint, the luminescence of the phosphorescent phosphor can be improved without impairing the luminance of the phosphorescent phosphor. As the resin component, a thermoplastic resin such as a polyolefin resin such as a polyethylene resin, a polyvinyl chloride resin, a polyamide, an ethylene-vinyl acetate resin, a fluorine resin, and a polyester can be used. For the thermosetting resin, epoxy resin, polyester resin, hybrid resin consisting of epoxy resin and polyester resin, acrylic resin, hybrid resin consisting of acrylic resin and polyester resin, fluorine resin resin, etc. are used. can do. When using a polyvinyl chloride resin-based resin, it is not preferable to use a compound containing a heavy metal such as lead as a stabilizer because it reacts with the phosphorescent phosphor and impairs the afterglow performance. In other resin systems, it is not preferable to use a compound containing a heavy metal such as lead or tin as an additive such as a reaction catalyst or a stabilizer for the same reason.

The ratio of the luminous phosphor to the resin is preferably 30/70 to 50/50 by weight. If the luminous phosphor content is less than this, the afterglow luminance of the coating film is low and the practicality is low. Even if the phosphorescent content is increased more than 50/50, the afterglow luminance of the coating film hardly increases.

The luminous phosphor powder coating composition of the present invention comprises a powder coating composition comprising a resin component, a powder coating composition comprising a binder obtained by mixing the above components as required, and other components. Any of the powder coatings added, and the phosphorescent phosphor is contained as a pigment, and each of these powder paints and the phosphorescent phosphor may be dry-blended as described above. Other components may be added when the paint and the phosphorescent substance are dry-blended.

As a method of applying the luminous phosphor powder coating of the present invention, the luminous phosphor powder coating can be applied directly to the object to be coated, but the ground color of the object has an adverse effect on the coating film of the luminous phosphor powder coating. In such a case, it is preferable to apply a high-brightness paint without heat yellowing first, form a base film, and then apply a phosphorescent phosphor powder paint as usual. In order to prevent heat yellowing, a paint using, for example, a heat-resistant resin is used, and in order to increase brightness, a paint using a high-brightness colorant such as, for example, a white pigment is used.
In this case, the coating for the base film may be a liquid coating,
The above-mentioned powder coating may be used. At this time, the underlying film is heated,
Alternatively, a phosphorescent phosphor powder coating may be applied in a wet state with a solvent, or in the case of a liquid coating in an undried state, so as to improve the adhesive strength of the coating to the object to be coated. Further, the phosphorescent powder coating may be baked by the heating.

In the method of applying the phosphorescent phosphor powder coating and the base powder coating, these powder coatings are applied to the surface of the object to be coated via a base film or directly. It is possible to use an electrostatic coating method in which a charged powder coating is supplied to the grounded surface of the object to be coated and the powder coating is applied to the surface of the object by electrostatic attraction. The powder paint can be adhered to the surface of the object to be coated without the need for attractive force due to static electricity, so that the powder paint is simply mechanically sprayed, for example, the powder paint is transferred from a hopper by a transfer device. It may be sprayed through a screen that is stopped or vibrating back and forth on the surface of the object to be coated, may be sprayed without applying a voltage, or may be sprayed with powder paint, or high-pressure air may be applied from a perforated plate provided at the bottom of a closed container. The gas is a jet, can any method capable of supplying a flow immersion method other powder coating for coating putting the coated body in a fog was brow up powder placed on the porous plate is applied. To bake the applied powder coating powder,
The heating method may be convection heating, heating by irradiating near-infrared rays, far-infrared rays (ceramics or the like as a radiator), or any other baking means.

In the present invention, the object to be coated is a metal substrate, a wooden substrate, concrete, casting, ceramic product,
A porous substrate such as a paper product or the like, or any other substrate to which a powder coating can be applied, such as electrostatic coating or spray coating described below, can be used.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As will be described in detail in the following examples, mixing of a powder coating material and a luminous phosphor is performed with a classified particle size. Since there is no contact, the particle size of the phosphorescent phosphor is maintained, and its afterglow performance is not impaired. Also,
The use of a base film having no thermal yellowing and high lightness can prevent the luminance of the coating film of the phosphorescent phosphor powder coating from being impaired.

[0018]

Next, embodiments of the present invention will be described. Less than,
“Parts” indicates “parts by weight”. Example 1 After weighing each raw material with the following composition, premixing, kneading with a bus kneader Co-Kneader PR-46, then pulverizing with a pulverizer, removing coarse particles with a 150 mesh sieve,
An epoxy resin powder coating for clearing is obtained. XAC-5017 71.9 parts (Nippon Ciba-Geigy Co., Ltd. epoxy resin EQ = 760) LS-H05 (phenolic curing agent) 25.9 parts 2MZ (Shikoku Chemicals 2-imidazole (curing accelerator)) 0.4 part Modaflow (flowing agent manufactured by Monsanto Chemical Co., Ltd.) 1.7 parts Total 100.0 parts The epoxy resin powder coating material and the phosphorescent phosphor were stirred and mixed for 15 minutes with a V-type mixer in the following composition, and then 100 mesh. To obtain phosphorescent phosphor powder coating material A. Epoxy resin powder paint 50.0 parts N night light DP-007 50.0 parts (Nemoto Chemical Co., Ltd. phosphorescent phosphor pigment) Total 100.0 parts In addition, the particle size distribution (interval distribution, cumulative) of N night light DP-007 2) is shown in FIG. The average particle size is about 20 μm,
As can be seen in comparison with the particle size dependence of the afterglow luminance, particles having a larger particle diameter than the average particle diameter mainly contribute to the afterglow luminance.

Next, in order to apply the phosphorescent phosphor powder coating material A, a metal plate having a thickness of 1 mm and a length and width of 1000 mm was coated on a metal plate having a powder size of 4000 and a white base (a polyester powder coating material manufactured by Toube Co., Ltd.). , White) by electrostatic powder coating, baking at 160 ° C for 20 minutes, film thickness 40 µm
To form a coating film. Next, the white painted plate is heated so that the temperature of the white painted plate becomes 230 ° C. by the residual heat. Then, the phosphorescent phosphor powder coating material A was applied using an electrostatic powder coating machine and baked. The thickness of the coating film was 250 μm, and the total thickness with the white coating film was 290 μm. The coated plate was allowed to stand overnight to dark in the dark state, after completely removing the afterglow, using D ₆₅ common light source, 400 Lx afterglow luminance after excitation 20 minutes at an intensity of (mcd / m ² ) was measured. Table 1 shows the results.

Example 2 In Example 1, an epoxy resin powder paint and N nocturnal DP-
A phosphorescent phosphor powder coating material B was obtained in the same manner except that the mixing ratio with 007 was changed as follows. Hereinafter, the same raw materials as in Example 1 will be described only by their trade names. Epoxy resin-based powder coating 70.0 parts N night light DP-007 30.0 parts Total 100.0 parts This phosphorescent phosphor powder coating B was also applied in the same manner as in Example 1, and the coated body was tested. Table 1 shows the results.

Example 3 Each raw material having the following composition was weighed and premixed, kneaded with a bus kneader Co-Kneader PR-46, crushed with a crusher, and coarse particles were removed with a 150-mesh sieve.
A thermoplastic polyester resin powder coating for clearing is obtained. 98.0 parts of Byron 200 (Toyobo company-made thermoplastic polyester resin) Modaflow 2.0 parts 100.0 parts in total 100.0 parts The thermoplastic polyester resin powder coating material and the phosphorescent phosphor were mixed in the following composition by a V-type mixer to obtain a mixture of 15 parts. The mixture was stirred and mixed for minutes, and then passed through a 100-mesh sieve to obtain a phosphorescent phosphor powder coating material C. Thermoplastic polyester resin powder coating 60.0 parts N luminous DP-007 40.0 parts Total 100.0 parts This phosphorescent phosphor powder coating C was also coated in the same manner as in Example 1, and the coated body was coated. The test results are shown in Table 1.

Example 4 A steel plate having a thickness of 1 mm and a length and width of 1000 mm is spray-coated with a baking type acrylic resin paint (liquid paint) manufactured by Kawakami Paint Co., Ltd. Put the coated body in a dryer,
After heating for 0 minutes, take out and apply the phosphorescent phosphor powder coating material C as in Example 1. In this method, 1
Powder coating can be finished by one coat baking (single coating, single baking). Table 1 shows the results of testing the coated body in the same manner as in Example 1.

Comparative Example 1 The following materials were weighed, mixed for 5 minutes with a Henschel mixer (a mixer with a shearing force of a stirring blade), kneaded with a Buss Co. kneader PR-46, and then crushed with a crusher. The coarse particles were removed with a 150-mesh sieve to obtain a phosphorescent phosphor powder coating material a. XAC-5017 36.0 parts LS-H05 12.9 parts 2MZ 0.2 parts Modaflow 0.8 parts Benzoin 0.1 parts N night light DP-007 50.0 parts Total 100.0 parts This phosphorescent phosphor powder The coating material a was applied in the same manner as in Example 1, and the coated body was tested. The results are shown in Table 1.
In the above embodiment, the phosphorescent phosphor powder coating material may be directly applied to the object to be coated in some cases.

[0024]

According to the present invention, the phosphorescent phosphor does not react with heavy metals and does not impair its afterglow performance, and the phosphorescent phosphor maintains its particle size to improve its afterglow performance. It is possible to provide a phosphorescent phosphor powder coating material and a coating method thereof that do not cause harm. And the film thickness is sufficiently thick,
It is possible to provide a luminous phosphor powder coating material and a method of coating the luminous phosphor powder coating so that the display by the luminous phosphor can be performed clearly, by applying the ground color of the object to be coated through the base film. Can be hidden.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the particle size and luminance of a phosphorescent phosphor according to the present invention.

FIG. 2 is a graph showing the particle size distribution.

[Table 1]

Claims (4)

[Claims] 1. A luminous phosphor powder coating containing a luminous phosphor and a binder, wherein a powder coating composed of at least a resin component of the binder prepared in advance, and the luminous phosphor particles are A luminous phosphor powder coating containing a mixture in which the respective particle sizes are maintained. 2. The phosphorescent phosphor is an oxide compound represented by the general formula: MAl ₂ O ₄ (where M is at least one selected from the group consisting of calcium, strontium and barium). Europium is used as an activator for the magnesium-added oxide-based compound or the oxide-based compound or the magnesium-added oxide-based compound which is a mother crystal or a compound obtained by adding magnesium to the oxide-based compound. The phosphorescent phosphor powder coating according to claim 1, which is an activated phosphor compound added in an amount of 0.001% to 10% in mol% based on M. 3. The phosphorescent phosphor powder coating according to claim 1, wherein the resin component is a thermosetting resin or a thermoplastic resin. 4. The method according to claim 1, wherein a step of forming a high-brightness underlayer without thermal yellowing on the object to be coated, a step of heating the underlayer, and a step of heating the underlayer are performed. A method for coating a luminous phosphor powder coating, which comprises coating the luminous phosphor powder coating according to the above.