JP2007084622A - Light-accumulating color synthetic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-accumulating color synthetic resin, capable of solving such problems that color of conventional products given by mixing a light-accumulating fluorescent substance into a synthetic resin is usually restricted to luminescent color of the light-accumulating fluorescent substance, and therefore their uses are limited, and light emitted from the light-accumulating fluorescent substance is, on the other hand, blocked by a colorant, when the colorant is mixed into the synthetic resin, and therefore enough afterglow characteristics are not exhibited. <P>SOLUTION: This light-accumulating color synthetic resin has the enough afterglow characteristics, by setting an average particle diameter of the light-accumulating fluorescent substance which is mixed into the synthetic resin to about 20 μm, even when the colorant is mixed thereinto. Further, the light-accumulating color synthetic resin having the high afterglow characteristics and decreased color shading is obtained by melting the synthetic resin at a temperature higher than a melting point thereof by not less than 10°C and nor more than 30°C, when produced, and dispersing the light-emitting fluorescent substance in the molten resin, by kneading them. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a luminous synthetic resin using a colorant.

The property of accumulating the energy of light received from sunlight or electric light and emitting light for a long time in the dark is called luminous property, and the substance having luminous property is called luminous phosphor. Since phosphorescent phosphors can repeat light absorption, phosphorescence, and light emission as many times as possible, they are used for emergency displays such as emergency exits, clock faces, and accessories. The characteristics of the phosphorescent phosphor are characterized by the emission color, the emission luminance, the afterglow time (the time for which light continues to be emitted after the light irradiation is stopped), and the like. There are two types of phosphorescent phosphors whose main crystal is zinc sulfide (ZnS) and those whose main crystal is strontium aluminate (such as SrAl ₂ O ₄ ). The former phosphorescent phosphor emits yellowish green light, and the afterglow time is about 0.5 hours. The latter phosphorescent phosphor emits green light and has an afterglow time of 5 hours or longer.

As an example of the usage pattern of the phosphorescent phosphor, as disclosed in Patent Document 1, a product obtained by adding a phosphorescent phosphor to a synthetic resin can be cited. In order to sufficiently exhibit the light emission characteristics of the phosphorescent phosphor, the synthetic resin is preferably transparent. This is because when the synthetic resin is colored, the light emitted from the phosphorescent phosphor is absorbed by the colorant, and the emission luminance of the synthetic resin decreases.
Japanese Patent No. 3260995

  However, the color of the synthetic resin is limited to the emission color of the phosphorescent phosphor simply by adding the phosphorescent phosphor to the transparent synthetic resin. In such a case, since the synthetic resin to which the phosphorescent phosphor is added cannot be a consumer's favorite color, the use is limited. For example, when using a synthetic resin with a strontium aluminate salt phosphorescent phosphor added to a red wall, the green color of the phosphorescent phosphor is noticeable when the illumination is on, and the appearance of the building It will be lost. In order to further increase the demand for a synthetic resin to which a phosphorescent phosphor is added, it is necessary to color the synthetic resin in a consumer's favorite color and maintain the phosphorescent property. In the case of coloring a synthetic resin, a method of mixing a desired colorant in the resin has been conventionally performed. However, when mixed with a phosphorescent phosphor, light emitted from the phosphorescent phosphor by the colorant is emitted. There is a problem that it is difficult to be released to the outside, and the synthetic resin does not have sufficient luminous properties.

  In order to solve the above-mentioned problems, an object of the present invention is to obtain a synthetic resin that exhibits sufficient luminous properties even when a colorant is added. That is, the first invention provides a luminous color synthetic resin comprising a synthetic resin, a luminous phosphor having an average particle size of 10 μm or more and 30 μm or less, and a colorant. A second invention provides the phosphorescent color synthetic resin according to the first invention, wherein the phosphorescent phosphor is contained in an amount of 1% by weight to 20% by weight with respect to the synthetic resin. 3rd invention provides the luminous color synthetic resin as described in 1st or 2nd invention in which the said coloring agent is contained 0.1 to 0.3weight% with respect to the said synthetic resin. To do. A fourth invention provides the phosphorescent color synthetic resin according to any one of the first to third inventions, wherein the phosphorescent phosphor is a strontium aluminate salt phosphorescent phosphor. According to a fifth aspect of the invention, there is provided a melting step in which a synthetic resin is melted to a temperature not lower than 0 ° C. and not higher than 50 ° C. above the melting temperature, and a mixture in which a colorant and a phosphorescent phosphor are added to the synthetic resin melted in the melting step A method for producing a phosphorescent color synthetic resin comprising: a kneading step for kneading a mixture of 1 to 30 minutes; and a molding step for molding the mixture kneaded in the kneading step.

  According to the present invention, it is possible to obtain a synthetic resin that exhibits sufficient luminous properties and is colored in a consumer's favorite color. Therefore, it is possible to increase the demand for synthetic resins to which phosphorescent phosphors are added.

  The best mode for carrying out the present invention will be described below. Note that the present invention is not limited to these embodiments, and can be implemented in various modes without departing from the scope of the invention.

  The first embodiment will mainly describe claims 1, 2 and 3. The second embodiment will mainly describe claim 4. The third embodiment will mainly describe claim 5.

<Embodiment 1>
<Embodiment 1: Concept>
The present embodiment relates to a synthetic resin having a phosphorescent property and colored in a color other than the luminescent color of the phosphorescent phosphor.

<Embodiment 1: Configuration>
The luminous color synthetic resin of the present embodiment is made of synthetic resin, luminous phosphor and colorant. In addition, glass fibers, silica, silicone spheres, and the like may be mixed as necessary.

  The synthetic resin is a base material for the luminous color synthetic resin. Synthetic resins include thermoplastic resins and thermosetting resins, but thermoplastic resins are more preferable because they are easy to process. Examples of the synthetic resin used in this embodiment include polyethylene terephthalate, high density polyethylene, low density polyethylene, polypropylene, polystyrene, polycarbonate, polyoxymethylene, acrylonitrile butadiene styrene copolymer, polymethyl methacrylate, nylon 6, and nylon. 66, polybutylene terephthalate, styrene butadiene rubber, ethylene propylene diene terpolymer, thermoplastic polyurethane, hard and soft PVC resins, and the like.

  The phosphorescent phosphor has an average particle size of 10 μm or more and 30 μm or less. In general, the phosphorescent phosphor has a higher light emission luminance as the average particle size is larger. Therefore, the average particle size is preferably 10 μm or more. On the other hand, if the average particle size is too large, molding becomes difficult, and the surface of the molded product becomes rough and poor in appearance, so the particle size is preferably 30 μm or less.

  The colorant is a pigment for mixing with a synthetic resin to develop a specific color tone. Examples of the colorant used include carbon black (black), phthalocyanine blue (blue), dimethylquinacridone (red), monoazo (yellow), titanium oxide (white), and the like. The colorant is preferably contained in an amount of 0.1 to 0.3% by weight based on the synthetic resin. When the content of the colorant is 0.1% by weight or less, the phosphorescent color synthetic resin is not sufficiently colored. This is because the afterglow characteristics of the resin deteriorate.

  Applications of the luminous color synthetic resin of the present embodiment include stationery such as a ballpoint pen, evacuation route display, ornaments and fishing gear.

<Embodiment 1: Effect>
According to the present embodiment, it is possible to obtain a synthetic resin that exhibits sufficient phosphorescent properties and is colored in a consumer's favorite color. Therefore, it is possible to increase the demand for synthetic resins to which phosphorescent phosphors are added.

<Embodiment 2>
<Embodiment 2: Concept>
The present embodiment relates to a luminous color synthetic resin in which the luminous phosphor is a strontium aluminate salt system.

<Embodiment 2: Configuration>
In this embodiment, the phosphorescent phosphor used is a strontium aluminate salt phosphorescent phosphor. The strontium aluminate salt is a substance whose main constituent elements are three elements of Sr, Al, and O. Specific chemical formulas include SrAl ₂ O ₄ and Sr ₄ Al ₁₄ O ₂₅ . Since the strontium aluminate salt alone does not have phosphorescent properties, the phosphorescent phosphor is usually a substance in which a small amount of Eu, Dy, B or the like is added to the mother crystal with the strontium aluminate salt as the mother crystal. The contents of Eu, Dy, and B in the phosphorescent phosphor are 0.002% or more and 20% or less in terms of a molar ratio to Sr. The phosphorescent phosphor having SrAl ₂ O ₄ as a mother crystal emits green light, and the phosphorescent phosphor having Sr ₄ Al ₁₄ O ₂₅ as a mother crystal emits blue light. A phosphorescent phosphor using a strontium aluminate salt as a mother crystal has an afterglow time about 5 to 10 times that of a conventional phosphorescent phosphor using zinc sulfide as a mother crystal. It is also chemically stable and has light resistance.

A method for producing a strontium aluminate-based phosphorescent phosphor will be described. As starting materials, strontium carbonate (SrCO ₃ ), alumina (Al ₂ O ₃ ), europium oxide (Eu ₂ O ₃ ), dysprosium oxide (Dy ₂ O ₃ ), boric acid (B ₂ O ₃ ) and the like are used. The mixture is fired for several hours in a reducing atmosphere and at a temperature of 1200 ° C. or higher. The reason why the reducing atmosphere is used is to reduce Eu ³⁺ to Eu ²⁺ . Next, the obtained massive substance is pulverized and separated by a filter so as to obtain a powder having a desired particle size. Moreover, in order to remove impurities adhering to the obtained powder, it may be washed with a mixed solution of acetic acid and glycerin.

<Embodiment 2: Example>
FIG. 1 is a photograph of the surface of the luminous color synthetic resin of this embodiment taken with an optical microscope. The synthetic resin is colored orange. The granular substance shown in FIG. 1 is a phosphorescent phosphor whose mother crystal is represented by SrAl ₂ O ₄ . FIG. 1 shows that the average particle diameter of the phosphorescent phosphor is about 20 μm.

  FIG. 2 is another photoluminescent color synthetic resin, which is a photograph taken with an optical microscope of the surface of a light emitting luminance lower than that of the synthetic resin shown in FIG. The average particle diameter of the phosphorescent phosphor is about 50 μm, and other conditions are the same as those of the phosphorescent color synthetic resin in FIG. From the above results, it is understood that the average particle diameter of the phosphorescent phosphor mixed with the synthetic resin is appropriately about 20 μm.

FIG. 3 shows the afterglow luminance measurement result of the phosphorescent color synthetic resin obtained by mixing 5 wt% of the phosphorescent phosphor with respect to the synthetic resin, and FIG. 4 is the mixture of 10 wt% of the phosphorescent phosphor with respect to the synthetic resin. Synthetic resin is transparent, but because the phosphorescent phosphor weakens the transparency of the synthetic resin, the phosphorescent color synthetic resin containing 5 wt% phosphorescent phosphor is translucent and contains 10 wt% phosphorescent phosphor The phosphorescent color synthetic resin is opaque. The afterglow is recognized by the naked eye at about 0.3 mcd / m ² , and it can be seen that any color has an afterglow time of 1 hour or more.

<Embodiment 2: Effect>
Since the phosphorescent phosphor used in the phosphorescent color synthetic resin of the present embodiment has higher afterglow characteristics than the conventional zinc sulfide-based phosphorescent phosphor, a product with high emission luminance can be obtained.

<Embodiment 3>
<Embodiment 3: Concept>
The present embodiment relates to a method for producing a synthetic resin that exhibits sufficient luminous properties even when a colorant is used.

  The phosphorescent color synthetic resin manufacturing method of this embodiment includes a melting step (S0301), a kneading step (S0302), and a molding step (S0303).

  In the melting step (S0301), the synthetic resin is melted to a temperature higher than the melting point temperature by 0 ° C. or more and 50 ° C. or less. The melting temperature of the synthetic resin is preferably higher than the melting point temperature by 10 ° C. or more and 30 ° C. or less. When the melting temperature of the synthetic resin is higher than the melting point temperature + 50 ° C., darkening occurs due to the reaction between the synthetic resin and the phosphorescent phosphor, and when the melting temperature is lower than the melting point temperature + 10 ° C., the synthetic resin is not sufficiently softened and kneaded. Have difficulty.

  In the kneading step (S0302), a mixture obtained by adding the colorant and the phosphorescent phosphor to the synthetic resin melted in the melting step (S0301) is kneaded for 1 minute to 30 minutes. When the kneading time is 1 minute or less, the phosphorescent phosphor is not sufficiently dispersed in the synthetic resin, resulting in uneven color during light emission. When the kneading time is 30 minutes or longer, the synthetic resin reacts with the phosphorescent phosphor, and darkening occurs.

  In the molding step (S0303), the mixture kneaded in the kneading step (S0302) is molded. As molding methods, there are mainly extrusion molding and injection molding. In extrusion molding, a kneaded mixture is passed through a mold to form a rod or plate, and the extruded rod or plate is cut into a desired shape. In injection molding, a kneaded mixture is poured into a mold and molded. In addition to these, there are molding methods such as transfer molding and compression molding.

<Embodiment 3: Effect>
According to this embodiment, a phosphorescent color synthetic resin in which phosphorescent phosphors and colorants are dispersed in the entire product can be obtained, and sufficient luminous properties can be exhibited and appearance can be improved.

A photograph of the surface of phosphorescent color synthetic resin observed with an optical microscope. When the average particle diameter of the phosphorescent phosphor is about 20 μm. A photograph of the surface of phosphorescent color synthetic resin observed with an optical microscope. When the average particle diameter of the phosphorescent phosphor is about 50 μm. Afterglow luminance measurement result of translucent type phosphorescent color synthetic resin. Afterglow luminance measurement result of opaque type phosphorescent color synthetic resin.

Claims (5)

Synthetic resin,
A phosphorescent phosphor having an average particle size of 10 μm or more and 30 μm or less;
A colorant;
Luminescent color synthetic resin.   The phosphorescent color synthetic resin according to claim 1, wherein the phosphorescent phosphor is contained in an amount of 1 wt% to 20 wt% with respect to the synthetic resin.   The luminous color synthetic resin according to claim 1 or 2, wherein the colorant is contained in an amount of 0.1 wt% to 0.3 wt% with respect to the synthetic resin.   The phosphorescent color synthetic resin according to any one of claims 1 to 3, wherein the phosphorescent phosphor is a strontium aluminate salt phosphorescent phosphor. A melting step in which the synthetic resin is melted to a temperature that is 0 ° C. or more and 50 ° C. or less higher than the melting point temperature;
A kneading step of kneading a mixture of the synthetic resin melted in the melting step with a colorant and a phosphorescent phosphor added thereto for 1 to 30 minutes;
A molding step for molding the mixture kneaded in the kneading step;
A method for producing a luminous color synthetic resin.