JPH0430037Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a plastic laminate having luminescent properties.

BACKGROUND ART Luminescent pigments are commercially available and have the property of accumulating light when received from sunlight, fluorescent lights, etc. and continuing to glow in the dark even after the light source has disappeared, and are used for a variety of purposes. For example, by mixing it with plastic to make a sheet or plate-like product,
It is used by cutting out the desired shapes and letters and pasting them on concrete. It can also be mixed with liquid synthetic resin and applied as a fluorescent paint. However, these luminescent products have various problems, such as reduced luminescence due to wear, combustibility, insufficient adhesive strength and easy to fall off, and high prices, making them extremely difficult to use. Limited.

The present inventors completed this invention as a result of studies to compensate for the above-mentioned drawbacks.

This device is a laminate product in which a luminescent layer obtained by polymerizing and curing a liquid transparent synthetic resin containing a luminescent pigment is provided on a transparent synthetic resin layer containing 50% by weight or more of an inorganic filler.

The light-emitting layer can be formed from a transparent synthetic resin and a light-emitting substance such as a luminescent pigment.

Luminescent pigments are substances that emit phosphorescence, such as artificial alkaline earth metal sulfides (calcium sulfide, strontium sulfide, barium sulfide).
It is a phosphor whose main ingredients are zinc sulfide and the like, with trace amounts of heavy metals (manganese, copper, lead, zinc) added. When a small amount of radioactive element such as radium is added to these luminescent pigments, the radiation causes them to retain phosphorescence for a long time and continue to emit light in the dark. Products made from zinc sulfide as a base material, with a trace amount of copper added as an activator, mixed with an alkali metal flux, and fired are less likely to darken due to sunlight, etc., than alkaline earth metal sulfides. stability. The luminescent pigment may be contained in the luminescent layer in an amount of about 0.5 to 50% by weight.

One of the other components used in the present invention is a transparent synthetic resin. Specifically, they include furan resin, epoxy resin, unsaturated polyester resin, urethane resin, polystyrene resin, and methacrylic resin. The greater the transparency of the synthetic resin, the greater the luminance of the laminate. Particularly preferred synthetic resins are unsaturated polyester resins and methacrylic resins.

Unsaturated polyester resin is made by mixing a vinyl compound such as styrene with an unsaturated polyester obtained through a polycondensation reaction of a glycol compound and an unsaturated dicarboxylic acid, and using a catalyst to cause crosslinking by a polymerization reaction and hardening. It is a polymerizable liquid synthetic resin. When unsaturated polyester resin is used, the surface hardness of the laminate is high.

Liquid synthetic resin (hereinafter sometimes referred to as "acrylic syrup"), which is a polymerizable mixed solution of methyl methacrylate polymer and a monomer mainly composed of methyl methacrylate, is produced by a polymerization reaction using a catalyst. and give methacrylic resin. When methacrylic resin is used, a laminate product with excellent properties such as water resistance, weather resistance, and luminance can be easily obtained. In the methacrylic resin, the content of methyl methacrylate units is preferably about 50% by weight or more. The acrylic syrup preferably contains about 5 to 40% by weight of methyl methacrylate polymer and has a solution viscosity of about 0.5 to 30 poise at 25°C. Examples of the catalyst include radical polymerization catalysts such as benzoyl peroxide, lauroyl peroxide, and azobisisobutyronitrile. Radical polymerization catalysts can be used alone or in combination with other substances. When a redox catalyst, for example a combination of a peroxide such as benzoyl peroxide and a tertiary amine such as N,N-dimethylaniline, is used, unsaturated polyester resin liquid and acrylic syrup can be produced not only under heating but also at room temperature of 10 to 35°C. Can be cured in a short time.

The laminate of the present invention is obtained by pouring a mixture containing the polymerizable liquid synthetic resin onto a layer with or without luminescent properties and polymerizing and curing the mixture. Adhesives and adhesive operations are not particularly required to produce the laminate. Since the laminate is integrated by polymerization and curing of the synthetic resin, there are advantages such as easy and complete integration, and the shape of the laminate is not easily restricted.

The laminate according to the present invention contains a large amount of inorganic filler. Therefore, a product with excellent flame propagation resistance (flame retardancy), abrasion resistance, shape stability, etc. can be obtained. The inorganic filler is not an essential component in the light-emitting layer, or is an essential component in the layer provided below the light-emitting layer.

Specific examples of inorganic fillers include calcium carbonate, barium sulfate, talc, kaolin, alumina, alumina hydrate, mica, river sand, silica sand,
Examples include inorganic glass powder, crushed limestone, crushed serpentine, and the like, and these can be used alone or in combination of two or more. The layer provided below the light-emitting layer contains an inorganic filler in an amount of 50% by weight or more, preferably about 70% by weight or more. When such a large amount is included, the laminate of the present invention has excellent properties such as shape stability and flame retardancy. There are no particular limitations on the type of inorganic filler included in the layer provided below the light emitting layer.

Although an inorganic filler can be included in the light-emitting layer, the luminance may vary depending on the type of filler.

When an inorganic filler with an average particle size of about 0.2 mm or more is included in the light emitting layer, it is difficult to block the emitted light, so the luminance becomes high. When the luminescent layer contains an inorganic aggregate with an average particle size of approximately 0.2 mm or more, such as highly transparent silica sand containing approximately 50% by weight or more of silicon dioxide or calcium carbonate, or crushed limestone, the luminescence brightness is increased. . Other preferred inorganic fillers for use are hydrated fine-grained inorganic powders. Specifically, calcium sulfate dihydrate, basic magnesium carbonate dihydrate,
Alumina trihydrate, etc., and mixtures of these hydrated fine inorganic powders, unsaturated polyester resins, methacrylic resins, etc., are more sensitive than calcium carbonate, etc.
Emission brightness tends to increase, and the flame propagation resistance (flame retardance) of the laminate of the present invention is also highly improved.

This idea will be explained using figures. FIG. 1 and FIG. 2 are sectional views each showing one embodiment of this invention. Figure 1 shows a mixture of a polymerizable liquid synthetic resin and an inorganic filler placed on a luminescent synthetic resin (for example, a 2 mm thick methacrylic resin plate molded product containing 10% by weight of luminescent pigment). This is an example of a laminate product in which a light-emitting layer 1 and a synthetic resin layer 2 containing an inorganic filler are laminated and integrated during polymerization and curing by being filled and then polymerized and cured. It has characteristics such as good surface gloss, easy to obtain a desired shape, high strength, and flame retardancy.

2 shows another example of the present invention, in which a mixture of inorganic filler, phosphorescent pigment, and liquid synthetic resin is poured to a desired thickness (e.g., 2 mm) onto a non-luminous transparent synthetic resin (e.g., a methacrylic resin plate with a thickness of 1 mm), and then a mixture of inorganic filler and liquid synthetic resin is poured to a desired thickness (e.g., 20 mm) and cured to laminate and integrate three layers: non-luminous layer 2, luminous layer 4, and non-luminous layer 3. Since luminous layer 4 is protected by layers 2 and 3, the phosphorescent pigment is highly durable against sunlight, rainwater, etc. Therefore, it is particularly suitable for outdoor use.

In FIG. 2, layer 3 may be a preformed article, such as a hardened plate made of synthetic resin and inorganic filler, which is laminated together by a polymerizable liquid synthetic resin forming layer 4. can be converted into
If, instead of layer 2 in FIG. 2, it is poured onto a releasable casting surface (e.g. a steel surface), a laminate with particularly good abrasion resistance, in which layers 3 and 4 are integrated, is obtained.

Specific examples of the mixture for forming layer 3 include 10 to 20% by weight of an unsaturated polyester resin liquid having a viscosity of about 1 to 10 pounds at room temperature, 10 to 30% by weight of powder such as calcium carbonate, and coarse bones such as river sand. It is a mixture consisting of 50 to 80% by weight of carbon dioxide and a small amount of redox catalyst (such as a combination of methyl ethyl ketone peroxide and cobalt naphthenate). Can be polymerized and hardened.

A specific example of a mixture forming layer 4 is an acrylic syrup having a viscosity of about 1 to 10 pounds at 25°C.
~20% by weight, zinc sulfide phosphor with trace amounts of copper (specific gravity approximately 4) 1-10% by weight, alumina trihydrate 10
~20% by weight, 50-79% by weight of coarse aggregate such as crushed limestone, and a small amount of redox catalyst, and has similar polymerization hardening properties as described above.

The laminate of the present invention has excellent weather resistance, abrasion resistance, and flame retardancy, so it can be used as an emergency evacuation sign for outdoors, underpasses, tunnels, movie theaters where the public gathers, high-rise buildings, basements, etc. Suitable for marking tiles, etc. Furthermore, even after external light sources such as electric lights are extinguished, it emits light all the time or for 1 to 2 hours in the dark, so it also has a display effect and is suitable as a member of furniture and building materials.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views showing examples of embodiments of the laminate of this invention.

Claims (1)

[Scope of utility model registration request] A plastic laminate product having luminescence properties, which is formed by providing a luminescent layer obtained by polymerizing and curing a liquid transparent synthetic resin containing a luminescent pigment on a transparent synthetic resin layer containing 50% by weight or more of an inorganic filler.