JPH11106540A - Luminescent resin foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a remarkable luminescent effect by dispersing luminescent powder in a resin and sending sufficient light to a light storing material contained therein. SOLUTION: A synthetic resin is a thermoplastic resin or a thermosetting resin such as an ethylene-vinylacetate copolymer, polyolefin, an epoxy resin, a polyurethane resin, etc. A foaming ratio of a foamed product is preferably 2-30 times. A luminophor is a fluorescent material or a light storing material such as a strontium aluminate and a zinc sulfide having a diameter of 20-150 μm and 4-20 pts.wt. thereof is preferably formulated with 100 pts.wt. of the resin. It is further preferable to mix 10-35 pts.wt. of transparent glass beads having 10-300 μm for scattering and collecting of light. Abrasion resistance of the foamed product is enhanced by cutting a fluorescent resin foamed product having dispersed transparent glass beads and a fluophor with a sharp blade to expose the transparent glass beads and the fluophor on the cut surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin foam having a characteristic of emitting light in the dark.

[0002]

2. Description of the Related Art Hitherto, a luminous body having a property of emitting light in the dark by applying a luminous paint or containing a luminous substance has been used for nighttime display and emergency display.

[0003]

However, the conventional luminous body as described above has a problem that sufficient luminous intensity and luminous time cannot be obtained. Considering the cause, when the phosphorescent paint is applied, there is a large reason that a sufficient amount of light energy cannot be stored because the phosphorescent substance applied to the surface has only an amount to form a thin layer. If the phosphorescent paint is applied thickly, the amount of the phosphorescent substance will increase, but the lower phosphorescent substance will not be able to reach sufficient light energy due to the obstruction of the phosphorescent substance on the surface layer. Sufficient luminous intensity and luminous time could not be obtained in that, even if the luminous light was emitted, it did not reach the outside because it was hindered by the phosphorescent substance on the surface layer.

Further, even if the layer containing the phosphorescent substance is made thick to contain a large amount of phosphorescent substance, sufficient light energy does not reach the phosphorescent substance inside, as described above.
There is a problem that light emitted from the inside does not sufficiently reach the outside.

As described above, according to the conventional idea, even if the amount of the luminous substance is increased, only the cost is increased, and it is not an effective solution in terms of the light emission intensity and the light emission time. Therefore, an object of the present invention is to provide a luminous body capable of obtaining a remarkable luminous effect at a low cost by utilizing the function of the luminous substance to the maximum.

[0006]

The luminescent resin foam according to the first aspect of the present invention is characterized in that luminescent powder is dispersed in a synthetic resin foam. As the synthetic resin, a thermoplastic resin or a thermosetting resin may be used, and a polyolefin resin, an epoxy resin, a polyurethane resin, or the like can be used.

[0007] The expansion ratio of the foam is preferably 2 to 30 times. If the expansion ratio is too small, the voids are small and light is easily attenuated. If the expansion ratio is too large, strength cannot be obtained. The powder of the luminous body preferably has a particle size of 20 to 150 μm. If the particle size is too small, the emission intensity is weak and a large amount of luminous bodies must be dispersed, so that the cost increases. If the particle size is too large, uniform emission cannot be obtained due to uneven distribution. The content ratio of the luminous body powder to the synthetic resin is preferably 4 to 20 parts by weight, and more preferably 7 to 13 parts by weight, based on 100 of the synthetic resin. If it exceeds 20 parts by weight, it will be difficult to knead when dispersing it in the synthetic resin. If the amount is less than 4 parts by weight, the light emitting effect is insufficient.

The foam may be an open cell or a closed cell. The foaming method may be a mechanical foaming method such as forced stirring, a chemical foaming method by adding a chemical substance such as a carbonate, or a foaming method. A foaming method by heating or adding a substance having a low boiling point may be used.

[0009] The luminous body is a substance that emits fluorescence,
It is a substance having a light storage function or a substance having a coloring or light emitting function. The luminous body is, for example, strontium aluminate or zinc sulfide, and the ratio to the resin is 3% to 50%.

A second aspect of the present invention is characterized in that spherical transparent glass beads are dispersed in the luminescent resin foam of the first aspect. The transparent glass beads are preferably substantially spherical and transparent glassy. The particle size of the transparent glass beads is preferably 10 to 300 μm. If the particle size is too small, it is difficult to uniformly disperse the particles. If the particle size is too large, the presence of glass beads is unevenly distributed, and a uniform light emitting effect cannot be obtained. Further, the content ratio of the transparent glass beads to the synthetic resin is preferably 2 to 50 parts by weight, and more preferably 10 to 35 parts by weight, based on 100 of the synthetic resin. If the content ratio is too small, the effect is weak, and if it is too large, the cost increases.

The foam can be colored to a desired color using colored transparent glass beads.

According to a third aspect, the synthetic resin of the first or second aspect is an ethylene-vinyl acetate copolymer (EVA copolymer). The amount of vinyl acetate added is preferably 5 to 18 parts by weight.

According to a fourth aspect of the present invention, the surface state of the synthetic resin foam of the first, second or third aspect is such that the transparent glass beads and the powder of the luminous body are exposed. By shaping the luminescent resin foam in which the transparent glass beads and the powdered illuminant are dispersed with a sharp blade, the cut surface is in a state where the transparent glass beads and the illuminant are appropriately exposed. Especially,
The particles that hit the blade due to the elasticity of the luminescent resin foam are temporarily buried in the foam while elastically deforming the foam, and protrude after the blade passes by the elastic restoring force of the foam.
In this manner, a state in which the transparent glass beads and the particles of the light emitting body are appropriately exposed on the surface of the light emitting resin foam can be easily obtained.

According to a fifth aspect of the present invention, the synthetic resin foam of the first, second, third or fourth aspect is a foam formed of a single cell by independent foaming. By using independent foam,
Even if it is elastically deformed, it has a high restoring force and excellent compressibility and elastic restoring force can be obtained. In addition, because it does not allow water or air to pass, waterproof,
Soundproof and heat insulating properties can be obtained.

Since the luminous body is dispersed in the synthetic resin foam, there are many voids due to foaming and light attenuation is small, so that external light reaches not only the luminous body on the surface of the foam but also the luminous body inside. Light energy is effectively stored. Further, light emitted from the luminous body passes through the foam having many voids and sufficiently reaches the outside. In addition, because the transparent glass beads are dispersed, the voids due to foaming are in a state where it is difficult to attenuate the light, and in addition, the glass beads are also difficult to attenuate the light, so the light from the outside is more internal than foaming alone. Light also has little attenuation.

Further, since the transparent glass beads refract light, the light can be dispersed and collected. In particular, since the glass beads exposed on the surface collect light from the surroundings and transmit it to the inside, a high luminous action is obtained, and even inside the foam, light is dispersed and collected by the transparent glass beads. In order to spread the light evenly. By the above action, not only the light emitter on the surface but also the light emitter inside absorbs sufficient light energy in a short time, and when emitting light, not only light from the light emitter on the surface but also light from the internal light emitter Since the light is radiated to the outside, it is possible to effectively store and emit light.

Further, since the glass beads exposed on the surface have higher hardness than the foam, an effect of increasing the abrasion resistance of the foam can be obtained. Furthermore, by making the transparent glass beads substantially spherical, it is difficult to scratch the surface of the contacting object.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a luminescent resin foam according to the present invention will be described in detail with reference to the drawings. In FIG. 1, reference numeral 1 denotes a light-emitting resin foam, in which a light-emitting body 11 made of strontium aluminate and transparent glass beads 12 are dispersed on a base material 10 made of an ethylene-vinyl acetate copolymer (EVA copolymer). . On the surface of the foam, as shown, the luminous body 11 and the transparent glass beads 12 are held in an exposed state. 13 is a void formed by foaming.

The luminescent resin foam 1 has an ethylene-vinyl acetate copolymer (EVA copolymer) weight of 10%.
When it is set to 0, the light emitting body 11 has a particle diameter of 100 μm and 11 parts by weight, and the transparent glass beads 12 have a particle diameter of 100 μm and 23 parts by weight. Ethylene vinyl acetate copolymer (E
VA copolymer) is 8% with 15% vinyl acetate added.
It is double foamed and has a hardness of 50 degrees.

The luminous body is preferably a powder containing 3% to 50% of strontium aluminate. It should be noted that the above components and the like are only examples, and it goes without saying that various components can be used without departing from the scope of the claims.

According to the light-emitting resin foam 1 having the structure shown in FIG. 1, light from the outside emits light from the light-emitting body 11 exposed on the surface,
The transparent glass beads 12 and the substrate 10 are irradiated. Light directly applied to the light emitting body 11 on the surface is absorbed by the light emitting body 11 and stored. In the transparent glass beads 12 on the surface, light from all directions is collected and guided inside.
The light that has passed through the transparent glass beads 12 in this manner is guided to the inside with almost no attenuation, and a part of the light is emitted from the light-emitting body 1 inside.
The light is illuminated and illuminated, and a part of the illuminant is passed through while being attenuated by the base material 10, passes through another transparent glass bead or a gap, and is further illuminated and illuminated by the light emitting body 11 inside.

The light applied to the base material 10 on the front surface is attenuated while passing therethrough and reaches the inside.
The light is stored at 1, and a part of the light passes through the transparent glass beads 12 and is further guided inside.

Since there are many voids 13 inside the foam 1, light traveling from the outside to the inside is slightly attenuated and is guided further inside.
Further, the transparent glass beads 12 inside the foam 1 collect the light that has passed through the surrounding base material 10 by the lens effect, and efficiently guide the light further inside. Furthermore, some of the light refracted by the transparent glass beads 12 may be directed not only to the inside but also to the side or the front side. Therefore, the surrounding light-emitting bodies 11 receive light from various directions, and thus store light more effectively.

In this manner, the light applied to the surface is accumulated in each light emitting body 11 while being sequentially guided inside.
In particular, if only the base material 10 is used, the light-emitting body 11 inside the base material 10 is not attenuated due to attenuation.
In the interior of the device, a gap 13 that does not attenuate light and a transparent glass bead 12 that collects light are dispersed, so that sufficient light energy is guided not only to the luminous body 11 on the surface but also to the luminous body 11 inside. Also, the light is sufficiently stored in the light emitting body 11 inside.

Although the function of the gap and the transparent glass beads in the light storage has been described above, the light emitting body 11 inside the light emitting element is also similarly formed in the light emission by the gap and the transparent glass beads.
The light emitted from is also efficiently guided to the surface. Since the internal light is dispersed in various directions by the transparent glass beads 12 existing inside, the luminous body 11 having insufficient light storage receives light from another luminous body 11 and stores the light. Then, the insufficient light energy is gradually replenished, and light is emitted with the same light amount as other light emitters. In this way, light is emitted almost uniformly at all positions inside the foam 1 with the elapse of time after the start of light emission.

Thus, the entire foam 1 emits light uniformly.

As described above, according to the luminescent resin foam 1 having the above structure, when the surroundings are bright, the light energy of the surroundings is efficiently absorbed and stored in a short time, and when the surroundings are dark, the stored light is stored. Since the light energy is radiated brightly for a long time, the effect of being able to be clearly recognized even in darkness is obtained. In addition, an energy source such as a battery is not required, and excellent light emission characteristics of emitting light for 12 hours or more can be obtained as described later.

Next, the manufacturing process of the luminescent resin foam will be described with reference to FIG. The luminescent resin foam of the present invention is, for example, an EVA polymer containing 15% vinyl acetate, a strontium aluminate luminous body (particle diameter 100 μ) and transparent glass beads (particle diameter 100 μm).
μ) is dispersed and foamed 8 times to form a thick plate-like foam 5
Get 0. This foam 50 is made with a sharp blade and has a thickness of 3
A thin plate-shaped material 51 of mm is obtained. At this time, when the foam 50 is made with a sharp blade, if the tip of the blade hits the luminous body or the transparent glass bead, the luminous body or the transparent glass bead passes over the blade so as to be buried in the base material. That is, it is held in a state where a part thereof is exposed to the cut surface. In this way, a foam having the luminous body and the transparent glass beads exposed on the surface is obtained.

The material 51 is appropriately cut to form various commodities utilizing the light emitting action.

Experimental data of the light emission time of the material obtained as described above are shown in Tables 1 and 2 in comparison with the case of a solid body which is not foamed. Sample 1 is an EV without foaming
A light-emitting material composed of strontium aluminate is dispersed in a solid body of polymer A.

Components of each sample

[0032]

[Table 1]

Light emission time of each sample

[0034]

[Table 2]

Common Conditions for Each Sample Material Size Plate 10 cm × 20 cm Experimental Method After exposure to clear sunlight for 10 minutes, the time during which light emission could be distinguished in a dark room was measured as the light emission time.

Since the material 51 has flexibility and can be sewn freely, it can be processed into various products. For example, it is sewn in a bag shape and is convenient as a case of a mobile phone or PHS, and can be used for various signs and displays such as an emergency guidance sign. Also, a light emitting rope can be obtained by forming a string, and the string formed to increase the strength may be covered with a transparent tube made of vinyl chloride resin or a colored translucent tube. .

Furthermore, by using independent foaming, waterproofness, heat retention and flexibility can be obtained, and the specific gravity is small and buoyancy can be obtained. Therefore, it is an optimal material for life jackets and the like.

A night display for a doorknob will be described below with reference to FIG. 3 as an application example of the luminescent resin foam according to the present invention. In FIG. 3, reference numeral 20 denotes a night display for a door knob using the luminescent resin foam of the present invention. This night display body 20 for a doorknob is formed by hollowing out a central portion of a disk having an outer diameter of 135 mm and a thickness of 3 mm into a circular shape having an inner diameter of 90 mm.

As shown in FIG. 1, a luminous body 11 made of strontium aluminate, a base material 10 made of ethylene vinyl acetate copolymer (EVA copolymer), and Transparent glass beads 12 are dispersed. In addition, on the surface of the foam forming the night display body 20 for the doorknob, as shown, the luminous body 11 and the transparent glass beads 12 are held in an exposed state. 13 is a void formed by foaming.

According to the night display 20 for a doorknob using the luminescent resin foam having the above-described structure, when the surroundings are bright, the surrounding light energy is efficiently absorbed and stored, and when the surroundings are dark, the stored light is stored. It radiates energy and shines brightly in a ring, so the position of the door knob is clear even in the dark,
The effect that the door opens and closes smoothly is obtained. In addition, since an energy source such as a battery is not required, and light is emitted for 12 hours or more as described later, the effect that the position of the door is clear all night can be obtained.

Further, since it is a foam, it has an appropriate elasticity, and an effect that it can be easily attached to and detached from the door knob can be obtained.

Light reflecting means may be provided on the back surface of the night display body 20 for doorknob using the luminescent resin foam having the above-described structure, as viewed from the foam side. The light reflecting means may be, for example, a mirror-finished metal surface, and the metal surface may be a nickel film. Alternatively, a surface such as a white plastic may be provided. As a method of attaching the door knob night display body 20 to the door knob, it may be simply hung on the door knob, or may be adhesively fixed to the door by providing an adhesive layer on the back surface or the like.

The luminescent resin foam according to the present invention can be applied not only to a night display for a doorknob but also to various display means such as a display of a key ring or a switch.

[0044]

According to the luminescent resin foam of the first aspect of the present invention, since the luminescent powder is dispersed in the synthetic resin foam, there are many voids due to foaming and light attenuation is small. The external light reaches not only the luminous body on the surface of the foam but also the luminous body inside, so that light energy is effectively accumulated. Further, light emitted from the luminous body passes through the foam having many voids and sufficiently reaches the outside. In this way, the effect of absorbing and accumulating sufficient light energy in a short time and emitting light for a long time can be obtained.

According to a second aspect of the present invention, since spherical transparent glass beads are dispersed in the luminescent resin foam of the first aspect, the voids due to the foaming are in a state where light is hardly attenuated. Since it is difficult to attenuate light, both external light and internal light are less attenuated than foaming alone. In addition, the transparent glass beads refract light, thus providing a light scattering and collecting action. Therefore, light is sufficiently stored in a short time, and bright light is emitted for a long time.

According to a third aspect, since the synthetic resin of the first or second aspect is an ethylene vinyl acetate copolymer (EVA copolymer), a material having an appropriate elasticity and touch can be obtained.
It can be applied to various articles.

According to a fourth aspect of the present invention, the surface of the synthetic resin foam of the first, second, or third aspect is made such that the transparent glass beads and the powder of the luminous body are exposed, so that the glass exposed on the surface is provided. The beads collect light from the surroundings and transmit it to the inside,
High luminous action is obtained, and even inside the foam, light is dispersed and collected by transparent glass beads,
By distributing the light uniformly, a longer-time light-emitting effect can be obtained. In addition, the glass beads exposed on the surface are higher in hardness than the foam, so that the abrasion resistance of the foam is increased, and the transparent glass beads are made substantially spherical, thereby scratching the surface of the contacting object. This makes it difficult to develop many applications as an excellent material.

According to a fifth aspect of the present invention, since the synthetic resin foam of the first, second, third or fourth aspect is a foam formed of a single cell by independent foaming, it has a high restoring force even when elastically deformed. Compressibility and elastic restoring force are obtained. In addition, since it does not allow water or air to pass, waterproofness, soundproofness, and heat insulation can be obtained.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view near the surface of a luminescent resin foam according to the present invention.

FIG. 2 is a diagram illustrating a process for obtaining a thin material from a foam.

FIG. 3 is a perspective view of a use state of a night display body for a door knob using the luminescent resin foam of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Luminescent resin foam 10 Ethylene vinyl acetate copolymer (EVA copolymer), base material 11 Luminous body 12 Transparent glass beads 13 Void 20 Night display for door knob

Claims (5)

[Claims] 1. A luminescent resin foam, wherein a luminescent powder is dispersed in a synthetic resin foam. 2. The luminescent resin foam according to claim 1, wherein spherical transparent glass beads are dispersed in the luminescent resin foam. 3. The luminescent resin foam according to claim 1, wherein the synthetic resin is an ethylene vinyl acetate copolymer. 4. The luminescent resin according to claim 1, wherein the surface of the synthetic resin foam is such that the glass beads and the luminescent powder are exposed. Foam. 5. The foam of a synthetic resin is a foam formed as a closed cell by independent foaming.
The luminescent resin foam according to 2, 3, or 4.