AU7821101A - Artificial stone and formation therefor - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: DOPPEL CO., LTD Invention Title: ARTIFICIAL STONE AND FORMATION THEREFOR The following statement is a full description of this invention, including the best method of performing it known to us: ARTIFICIAL STONE AND FORMATION THEREFOR Technical Field The present invention relates to an artificial stone and its formation. More particularly, the present invention relates to a noctilucent and/or luminescent artificial stone which is useful for a building material, a view material, or the like such as a direction indicator, or a location guide with a decorative or a dark-field illumination taking advantage of the luminosity with an accumulation of light or an absorption of ultraviolet rays, and its formation.

Background Art An artificial a tone caked fromamixture of a crushed natural scone with a resin or the like is conventionally known, Various ideas have been carried out to make this artificial stone have a design of a natural stone style such as marble or granite and besides superior hardness and strength.

As a trial for improving a function and performance of such 20 anartificial stone, it isproposedcogivea luminosity function .to the artificial stone with using a luminescent substance such as a noctilucent substance like a light accumulation material or an ultraviolet ray luminescent material emitting light with ultraviolet rays absorption.

Por instance, a luminescent tile which consists of an inorganic filler, a synthetic resin, and a light accumulation pigment and includes an inorganic filler of more than about 50 of the total amount, is proposed (Japanese Patent Laid-Open No.

60-137862). For instance, on this luminescent tile, a board of 3 to 5mm thick is proposed, which is molded and hardened from a composition of; 75 wt% of silica sand as an inorganic filler with an average particle diameter of 0.2 mm or more, 15 wt% of syrup consisting of MMA polymer/MMA monomer of 25/75 in a weight ratio, and 9 wt% of a light accumulation pigment.

In addition, a luminescent material obtained from the following composition is proposed; a natural or synthesized luminescent stone emitting light by ultraviolet rays and an adhesive resin of 4 to 10 wt% against a total amount along with a natural or synthesized aggregate (Japanese Patent Laid-Open No. 8-1197068).

However, a luminescent material such as a conventional artificial tile or artificial stone which is made noctilucent.

for instance, by the above light accumulation pigment has several hours at most: for sustaininga declining brightness over 3med/m 2 which is a lower limit at which a person can ensure a contour of things, from a saturated state after irradiation at 200Lx with a D65 commonly used light source: and the above proposed material (Japanese Patent Laid-Open No. 60-137862) has only one hour.

*In addition, there was a problem that brightness required for a clear visibility which is thought to be necessary for a refuge instruction in a power cut for about 15 minutes was not in an enough level. These problems were common as a problem that enough luminescence performance is not obtained either in case of a light emission by ultraviolet rays.

Furthermore, there was a problem that only a surface layer of 1 mm deep at most from the surface can emit light and a light accumulation material or the like included in a deeper side of S a compact of an artificial stone can not act at all, in either a case of an artificial atone (an artificial tile) being made noctilucent by blending a light accumulation pigment or a case of an artificial stone being made luminescent by ultraviolet rays.

For this reason, a thick light emission layer could not be provided. Thus there was a fundamental problem on luminescence performance described above that an extension of an noctilucent time was difficult, for instance, on an noctilucent artificial stone mixed with a light accumulation material.

Actually, owing to these problems, a practical use taking advantage of light accumulation noctilucence which fu.nction attracts attention as refuge induction guides in a power cut in an underground shopping center, for instance, is limited to 20 a paint, tape. or a film which includes the light accumulation material.

IT is not practical from the view point of a cost to blend a luminescent substance in an artificial stone as parts which Sdo not contribute to a light emission actually, because the S 25 noctilucent substance such as a light accumulation material and the luminescent substance with ultraviolet rays are expensive and raise a whole cost of an artificial stone product to 3 to times higher even with a small quantity of addition.

In addition, a conventional artificial stone could not be employed for floor materials, for instance, to which an abrasion resistance is required, as it has a problem not only in the luminescence performance but also in a physical property such as a strength, an abrasion resistance, and weatherability.

Thus, the performance and the use of the conventional artificial atone which is noctiluacent or luminescent with ultraviolet rays were extremely limited.

Considering these situations, the present inventors have proposed an artificial stone: which realizes a high strength and high hardness as an artificial stone including an inorganic aggregate and filler with a resin and a deep hue like a natural atone; allowsa light emission with thickness by blending a light accumulation material or an ultraviolet ray luminescent material; enables a contour thickness as an artificial stone Sto be bigger; and besides enables a luminescent time to be longer (for instance, W098/39268, W098/35919).

These proposals are essentially characterized by; using several groups of inorganic materials which average particle diameters are different, ina specific blending ratio; employing transparent inorganic materials for groups with bigger particle diameters; blending light accumulationmaterials or ultraviolet ray luminescent materials for groups with smaller particle diameters, or coating them beforehand on the surface of the transparent inorganic particles with bigger particle diamecers by baking or the like.

And these proposals were based on new findings that it is possible to increase a thickness contributing to a luminosity of a light accumulation material or the like by means of controlling an inner structure of the artificial stone.

Actually, an artificial stone based on the proposal of the present inventors enables brightness of 3 mcd/m 2 or more to continue for about 8 hours.

However, after that, the present inventors have investigated as a big subject to control a relationship between a structure of the artificial stone and the luminescence performance; for the purpose of improving the luminescence performance of light accumulation materials and luminescent materials with ultraviolet rays, for raising the initial brightness of light accumulation luminescence and besides enabling the luminosity at apredeterminedbrightness to continue for a longer time.

Iti torealize alightaccumulationluminescentarcificial stone which shows in maximum non energetic luminescence performance of a predetermined brightness at night or in a power 20 cut and a light emissive artificial stone with ultraviolet rays radiation which shows an energy-saving property in maximum.

Besides, concerning on the control, the present inventors have investigated as a subject to sustain and improve a physical property of extremely high quality and high function such as strength, surface hardness, abrasion resistance, weatherability, a color tone, and waterproofing/chemical resistance, for instance, which the present inventors have realized till now.

Disclosure of Invention The present invention provides the following artificial stones as a solving method for the above subjects; according to a first aspect, an artificial atone including at least one kind selected from a transparent aggregate, a light accumulation material, or a luminescent material by ultraviolet rays along with a resin being characterized by having higher luminescence performance of the artificial stone than that of the included light accumulation material and/or luminescent material by ultraviolet rays per se; according to a second aspect, said artificial atone being characterizedbyhavinghigh luminescence performance in a lower filling factor (volt) of the artificial stone than the maximum filling factor (vol%) of the included light accumulation material and/or luminescent material by ultraviolet rays per se.

In addition, the present invention provides; according to a third aspect, the artificial s one including a transparent 20 aggregate andat leastone kindselected froma light accumulation material or a luminescent material by ultraviolet rays along with a resin being characterized by that a particle diameter is 0.1 mmor more and 1/1.5 or less of a thickness of the artificial Stone after cast and hardened.

In addition, the present invention provides the followings related to the third aspect; according to a fourth aspect, the *artificial stone characterized by that a particle diameter of aggregates is 0.3 mm or more; according to a fifth aspect, the artificial stone characterized by that an average particle diameter of the transparent aggregates is 1/20 or more and 1/3 or less of a thickness of the artificial stone after cast and S hardened; according to a sixth aspect, the artificial stone characterized by that the transparent aggregates have an irregular surface configuration.

The present invention further provides; according to a seventh aspect, the artificial stone according to the above any one characterized by that each average particle diameter of a light accumulation material and/or a luminescent material by ultraviolet rays in 10 pm or more ard 300 usor less; and according to an eighth aspect, the artificial stone characterized by that the average particle diameter is 40 pm or more and 150 pm or less.

Thepresent inventionprovides; according to a ninth aspect, the artificial stone according to the above anyone characterized by including an inorganic filler with a particle diameter less o. than 0.1 mm; and according to a tenth aspect, the artificial 20 stone characterized by that the average particle diameter of the filler is 30 pun or more and 70 pm or less.

The present invention provides; according to an eleventh aspect, the artificial stone according to the above any one Scharacterized by that a volume rate of a transparency aggregate a is 20 or more and 80 or less and according to a twelfth aspect, the artificial stonecharacterizedby that avolume ratio o f a filler to a light accumulation material, a luminescent material by ultraviolet rays, ox the mixture of the both is 0 or more and 100 or less as filler/(light accumulation material and/or luminescent material by ultraviolet rays).

The present invention provides, according to a thirteenth aspect, the artificial stone characterized by that the transparent aggregate is quartz or rock crystal and the filler is aluminium hydroxide or silica.

The present invention provides, according to a fourteenth a9pect, the artificial stone characterized by that the transparent aggregate is a glass and the filler is silica or aluminium hydroxide.

Furthermore, the present invention provides; according to a fifteenth aspect, the artificial stone according to the above any one characterized by including a nontransparent aggregate along with a transparent aggregate and by that the particle diameter is 1/1.5 or less of a thickness of the artificial stone after cast and hardened and a total volume rate of a transparency aggregate and a nontransparent aggregate is 20 or more and 80 or less of the artificial stone.

o 20 The present invention provides, according to a sixteenth aspect, the artificial stone according to the above any one characterized by that a time from a saturated state after an exposure at 200 Lx with the P65 commonly used light source to brightness of 3 mcd/m 2 is 12 hours or longer.

The present invention provides; according to a seventeenth aspect, theartificialstonecharacterizedbythattheartificial stone of the above any one is lamination constituted as a surface material; and according to an eighteenth aspect, the artificial atone characterized by that the artificial stone of the above any one is constituted as a part of the surface.

The present invention as mentioned in the above is based on knowledges as the following which could be get as a result of the detailed examination by the inventor.

In other words, noctilucence/lumineacence performance is improved greatly with a structure of an artificial stone and its control, as for a structure/control in that case, Particle diameter of transparent aggregate; Configuration of transparent aggregate; Particle diameter of light accumulation material/ultraviolet rays luminescent material; Volume rate of transparent aggregate, and volume ratio against filler; Sort of transparent aggregate, and combination of it and sort of filler an above-mentioned factor,atc is made important, and it is effective to control these factors to a specified condition like 20 the present invention. These factors were made clear for the first time by an investigation of the present inventors.

Brief Description of Drawings Fig. 1 illustrates an aspect of cutting out the artificial stone and the surface processing; Fig. 2 illustrates a lamination composition of the noctilucent/luminescent artificial stone; Fig. 3 shows the recessed noctilucent/luminescent artificial stone; and Fig. 4 shows the integrated noctilucent/luminescent artificial stone by implantation.

Best Mod for Carrying Out the Invention The present invention has the above described features.

Preferred embodiments of the present invention will be described hereinafter.

Fundamentally, the concept in the present invention was not known in prior art at all. The above first and second inventions are provided as a new Icechnical concept which even the present inventors had not acquired as a finding before.

In other words, the noccilucent/luminescent artificial stone of the present invention is an artificial stone including a transparent aggregate, at least one kind selected from a light .accumulation material and a luminescent material by ultraviolet rays, and a filler mixed if needed along with a resin; being characterized by having higher luminescence performance of the 0*C artificial stone than that of the included light accumulation material and/or luminescent material by ultraviolet rays per *00 se.

The luminescence performance with such a feature has never been thought till now. It means that an artificial stone of the present invention, namely is realized as a blended complex .:oS with not only a light accumulation material and/or a luminescent material by ultraviolet rays but also a transparent aggregate, a resin, etc, has superior luminescence performance to that of a luminescent material and/or a luminescent material by ultraviolet rays per se.

The artificial stone having the superior luminescence performance is provided for the first time by the present inventors.

The luminescence performance of a light accumulation material and/or a luminescent material by ultraviolet rays per se, is evaluated in the following ways, for instance.

As for sole luminescence performance of these light accumulation materials and/or luminescent materials by ultraviolet rays per se. since theseare used ina form ofparticle* first of all. theseparticles are charged ina transparent vessel with an upper part opened and with a same depth as a thickness of the artificial stone in casting, and are pressurized with a vibration to be a close packed state. The condition shows the condition where particles consisting of light accumulation materials and/or luminescent materials by ultraviolet rays are packed in maximum keeping the initial size and shape without being damaged, and the condition where any longer it cannot be filledup anymore. This condition is composedby these particles Soee.,.

and air existing among these.

Then, the luminescence performance can be measured in such a close packed state.

For instance, after making each strontium aluminate based light accumulation materials (made in NEMOTO Co. Ltd.) with different particle diameters into the closed packing state in the container with a cepth of Snun. ahd carrying out an irradiation at 200Lx with the D65 light source for 60 minutes (more than saturation timie), initial brightnesseatter15 minures and a ecay time until brightness declines to 3 mcd/m' was measured, and was shown in Table 1.

0 00 0 00 0 *00 0 0 0 00 0 0 00 *0 00 000 0 0 0 00 00 0 00 0 0 0 000 000 0 0 0 0 0 0 0 0 0 00 00 0 0 0 0 0 0 0 0 0 0 00 0 0 0 000 000 000 Table I Light accumulation Average particle diameter (prm) material 102 4 015 0 Maximum fitting factor 30.56 36.11 38.89 41.67 44.44 47.26 (volume Specific gravity 1.1 1.3 1.4 1.5 1.6 1.7 True specific gravity 3.6 3.6 3.6 3.6 3.6 3.6 Brigtnn after 15 minutes (mc/m' 102.3 148.5 189.3 301.8 405.6 395.2 Decay time to 3 mcd/m' 51hJOM 7hl~m l~h4Sn 10b1.5r 1611 17h On the other hand, an artificial stone including a light accumulation material with an average particle diameter of 150 pm shown in Table 1 as a composition, was cast and hardened to be an artificial stone of 5 mm thick, and its luminescence performance was measured. The results are shown in correspondence with a filling factor (volume of a light accumulation material in Table 2.

Table 2 Light accumulation Brightness after material filling factor 15 minutes Decay time to 3mcd/m 2 (volume (mcd/m 2 0.29 61.29 1.44 105.3 6h 3.19 178.6 10h45m 4,37 217.6 11.19 372.3 19h45m 15.61 426.1 24h o By the way, brightness and its decay in Table 1 and Table 2 are measured with "BW33 luminance meter" made by TOPCON 9 CORPORATION. It is similar in the following description as well.

As is clear, for instance, in a comparison between Table 1 and Table 2 for a case of a light accumulation material of average particle diameter 150pm, it is understood that the decay time to 3 mcd/m 3 of an example of an artificial stone with a filling factor of 11.19 volume in the present invention was 19 hours and 45 minutes which exceeded a level of 18 hours of a light accumulation material per se; and that initial brightness after i minutes of an artificial stone with a filling factor of 15.61 volume was alsohigher than that of a light accumulation material per se.

These kind of resulto are confirmed not only in case of a light accumulation material with an average particle diameter of 150 um, but also in any case with 10 to 300 pm shown in Table 1.

It is thought tobe common that the luminescence performance of a sole luminescent material will drop bymeans of being blended with other components. However, it is surprising that the luminescence performance of the artificial stone of the present invention is superior to that of a aole light accumulation material, in other words, that the luminescence performance is, on the contrary, improved with blending, being different from such a common knowledge.

The following reasons can be guessed.

In the artificial stone, almost all light accumulation materials caneffectivelyabsorbanenergyof light (ultraviolet rays) given with radiation such as a sun light and a fluorescence light, as a result of scattering or irregular reflection of the light in inside of the artificial stone due to a blend or a conjugation with transparent aggregates and others.

Therefore, the absorbed light in inside of the artificial stone is accunulated effectively and che luminescence can be made effective.

The above-mentioned phenomenon is recognized not only in a light accumulation material but also in luminescent materials by ultraviolet rays of the present invention.

Thus, in the present invention, a composition is provided for a preferred artificial stone to allow the above-mentioned phenomenon.

This artificial stone, at first, comprises an inorganic aggregate, a light accumulation material (in other words, a light accumulation luminmucent material) or a luminescent material emitting light by means of ultraviolet irradiation, and a resin, wherein a part or a whole of said inorganic aggregate consists of a transparent aggregate. When a transparent aggregate is one part of the inorganic aggregate, the ratio is determined with a consideration to a physical function which is needed by an application of a noctilucent/luminescent artificial stone of the present invention or its formation, and to a luminescent function.

Therefore, in the present invention, the transparent aggregate is included as an indispensable matter.

And the artificial stone includes, as needed, an inorganic r organic filler, and a minor constituent of a silane coupling agent, a hardening agent, or the like.

A transparent aggregate in these compositions includes inorganic substances with a high transparency such as quartz (silica rock), rock crystal, glass, and silica, for instance.

For these transparent aggregates, an inorganic aggregate such Snatural rocks of no-transparency, minerals, and ceramics as natural rocks of non-transparency, minerals, and ceramics can be concomitantly employed in a permitted range.

A filler blended with anaggregate asneededis small granule powder with a much finer particle diameter than aggregate, and includes, for instance, inorganic substances such as aluminium hydroxide, glass powder, silica powder, quartz (silica rock) powder, and calcium carbonate, and organic substances such as plastic powder or a plastic bead.

Fora light accumulation material ora luminescent material by ultraviolet rays, various kinds of materials including a conventionally known material or a commercial material can be employed appropriately. There is, for instance, a strontium aluminate base substance, a zinc sulfidebase substance, or the like.

As a result of further investigation on details of the noctilucent/luminescent artificial stone which inventors have already proposed, the present inventors have found that the luminescence performance can be unexpectedly and remarkably improvedwith a minute control of the structure, and have proposed the followings. One of the important factors is, in the first place, a particle diameter of a transparent aggregate.

By the way, the luminescence performance is evaluated with a light accumulation luminescence in the following. In the evaluation method, according to JIS "light accumulation safety sign board" Z9100-1987. after irradiating at 200Lx by the common light source until brightness is saturated, a decay time until brightness becomes 3 mcd/ma is considered as the standard in the case of evaluating a performance. Incidentally.

brightness of 3mcd/m is considered to be a lower limit at which a person can visibly identify a contour of a thing. In addition, in the present invention, brightness at an elapsed time after irradiation such as initial brightness after 15 minutes is also evaluated.

In the present invention, the particle diameter of the transparent aggregate is determined to be 0.1 mm or more and 1/1.5 or less of a thickness of the artificial stone after the artificial stone was cast and hardened. In the above, "cast and hardened" means a state that a material mixture or a composition of the artificial stone in a flow condition is formed and hardened with compression or the like after being cast in a mold or is formed and hardened to a predetermined shape from the flow condition by means of a continuous belt formation or the like. The particle diameter of a transparent aggregate is determined to be 1/1.5 or less of a thickness of the artificial atone in such a "cast and hardened" state.

In the present invention, a preferable particle diameter of the aggregate is determined to be 0.3 mm or more.

In case of a particle diameter of a transparent aggregate with less than 0.1 mm. the decay time to brightness of 3 mcd/m is merely several hours, namely, i to 3 hours which is the same performance as the conventional one. In order to make the time at least six hours, the maximum particle diameter of the transparent aggregate must be 0.1 mm or more of a thickness of the artificial stone. In order to make the time for reaching form the saturated state to the brightness of 3 mcd/m 2 8 hours or longer and further 12 hours or longer, the preferable particle diameter may be 0.3 mm or more.

On the other hand, the particle diameter should be 1/1.5 or less of the thickness of the artificial stone. Because, in a case exceeding 1/1.5, a practical noctilucent/luminescent artificial stone is not actually provided, as a physical property such as strength required to the artificial stone is difficult to be obtained after the artificial stone was cast and hardened.

The luminescence performance of the artificial stone (a board thickness of 5 mm) including merely 2 vol% (3.89 wt%) of an strontium aluminate base light accumulation material (NEMOTO Co., Ltd., G-300C) for a light accumulation material, for instance, is indicated in Table 3. In Table 3, .the results are shown with the decay time after a saturated state being irradiated at 200Lx with the D65 commonly used light source for 60 minutes.

A composition (volume of the artificial stone is as Quartz (pulverized product) 19.98 Aluminium hydroxide 32.11 (average particle diameter 40 pm) Light accumulation material 2.00 (average particle diameter 40 pm) MMA resin 44.74 *i Others remainder S 25 (Silane coupling agent, a hardening agent, etc.) TablA 3 Luminescent timne Out diamneter range (mm) after irradiation Us than byliht(h) 2.5-1.2 1.2-0.6 0.6-0.3 0.3-0.1 1 35.47 29.48 30.39 24.56 14.23 2 16.82 13.20 13.16 11.13 3.871 4 7.253 5.957 5.671 4.97 1 6 4.372 3.972 3.872 3.082 8 3.326 3.121 3.012 3.087 In the table 3. about sample5 including merely 2 vol% of alight accumulation mate riial, chanige of the brightness (med/n 2 by the time after radiation is shown for every quartz particle diameter range.

Table 3 shows that it is necessary to not the aggregate partice di.ameter to 0.1mmn or more. and that it in desirable .*10 to set aggregate particle diameter to 0.3mm or more ini order to make time to 3 med/rn into 6 hours or longer.

In addition, when the particle diamger of the transaparent aggregate exceeded 1/1.5 of the board thickness, that is 3.4 mm', though the result isnot shownin Table1, the cast and hardened artif icial stone had a weak bend strength and was not a practical product.

In addition, when the aggregate particle diameter is less than 0.-1 mmI the luminmacence performance wao improved with an increase of blending rate of a light accutnuldtion material.

However, as a light accumulation material is an extremely expensive, it is not practical to increase the used quantity at all. For this reason, it is extremely important for the noctilucent/luminescent artificial stone to achieve the best luminescence performance with a minimum use rate of a light accumulation material.

In such a point of view, a prescription of the particle diameter of the transparent aggregate related to the present invention shows a conspicuity of the invention.

In the present invention, the average particle diameter of the transparent aggregate is further preferably 1/20 or more and /3 orlees of the thickneesof the east and hardenedartificial stone. By making average particle diameter into this range.

it becomes possible to lengthen certainly the decay time until brightness declines to 3 mcd/m 2 in 12 hours or longer.

Table 4 shows changes of the decay time to brightness of 3 mcd/m 2 with variation of average particle diameters of quartz on the artificial atone (board thickness of 5 mrn) of the following 0 composition (volume

S*S*

Quartz (pulverized product) 49 Aluminium hydroxide 14 (average particle diameter 40 pm) Light accumulation material G-300C (average particle diameter 40 pm) MMA reein 31 In the above composition, minor constituents such as a silane coupling agent or a hardening agent are omitted. It is similar in the following description as well.

Table 4 Maximum particle Average panicle Time to 3 mcd/n 2 diameter (mm) diameter (mm) 2.38 0.25 12hl5m 2.38 1.0 13h30m 2.38 1.2 13h45m 2.38 1.6 13h 2.38 1.8 9h45m Time to 3 mcd/ m 2 after irradiation at D 65 200Lx X 60 minutes (more than saturation time) is shown.

From Table 4, a significance of the average particle diameter with 1/20 or more and 1/3 or less of a board thickness 10 of a cast and hardened artificial stone is understood.

on the other hand, it is preferable to employ a transparent 0* aggregate, having not a regular crystal cleavage plane and not a spherical shave but an irregular surface configuration. This is characterized at first in a comparison between quartz (silica 15 rock) and rock crystal. These are usually pulverized to become a predetermined particle diameter of product. A pulverized product of rock crystal tends to have a regular surface as it is highly crystalli2ed- On the other hand, a quartz product does not have such a tendency. The quartz product consists of grains with an irregular and rough-hewn surface configuration as a whole. In addition, in case of a glass bulb, there is not such an irregular surface on it as is seen ona pulverized product of quartz or normal glass.

Such a difference affects the luminescence performance of the noctilucent/luminescent artificial stone.

Table 5 shows such a contrast.

In any case, composition (volume was as follows.

Transparent aggregate Aluminium hydroxide 14 Light accumulation material G-300C MMA resin The maximum particle diameter of the transparent aggregate was 2.38 mm, and the board thickness of cast and hardened artificial stone was S na. The decay time to 3mcd/m 2 after irradiation at 200Lx with the D65 commonly used light source to a saturated state is shown in Table S.

Table S *0 Transparent aggregate Decay time to 3 mcd/m Glass pulverization product 1 Glass ball 9h Quartz pulverization product 13h SRock crystal pulverization product 8h30m A clear contrast is recognized in Table 5. It is guessed that such a contrast reflects a degree of irregular refraction frequexicy in grains of the light: which entered the transparent; aggregate. It is conceivable that r'ock crystal with a highly crystallized plane or a glass ball with a spherical ourface hae less degree of such an irregularity than the pulverized product of quartz or glass, Wheun it explains more an f or the light accumulation material blended with che nort:i lucent/ luminescent artiricial san& i~n case of the present invention, according to the examination by the present inventors, it confirms that it in excellent with a viewpoint of the lumninuous perform~ance as much as the particle diarieter of the light accumulation material is large, that r-he time necessary for irradiation by light for roachirig the initial saturated state gets long on one aide ao mchas aparticle diameter is largre.

For ingtance, about the artificial otone including 5 vol% of a lighr- accumulation macerial, 49 volt of an aggregate ana 31 vol% of MEA resin, as is shown in Table 6, it is understood that it is desirable to use a strontium aluminate base light accumulation material with an average particle diameter of Pm~ or more, further preferably 40 pim or more, in order to extend the decay time to brightness of 3 mcd/n 2 after irradiation at 200Lx with D65 to a aturated state in miore than 12 hours.

Table 6 Average particle diameter of light accumulation material (pm) Brightness/time 20 40 80 150 Brighmess after 3.213 3.809 4.346 4.529 4.975 ten hours (mcd/m2) Brightness after 3.007 3.415 3523 4079 12 hours (mcd/m) Decay time to 10hlim 12h 13hlSm 13h30m 15hl5m 3 mcd/m In the present conditions, it is desirable to employ the average particle diameter of less than about 300 pm and further preferably less than 150 pm from a view point of availability.

In addition, in the artificial atone of the present invention, an inorganic filler with a smaller particle diameter than the inorganic aggregate such as said transparent aggregate.

in other words, with a parccile diameer less than 0 1 mm, can 10 be used. A blend of these inorganic fillers is not always needed for a composition of the noctilucent/luminescent artificial stone of the present invention. However, the filler is expected to enable a used amount of a resin in a composition of the artificial stone tobe reduced, to contribute toa dense structure 15 of theartificial stone, andfurther tocontributetoaneffective

S

luminescence with a little amount of used light accumulation materials.

The preferable average particle diameter of these filler is 30 pm or more and 70 pm or less.

The filler with a particle diameter of 0.1 mm or more makes it difficult toprovide adense structure in the artificial stone, and consequently makes a factor fr decreasing the luminescence performance.

In the noctilucent/luminescent artificial stone of the present invention, blending ratio of the aggregate, filler, and a light accumulation material and/or a luminescent material should be paid attention along with a definition on the particle diameter as the above. In the blending ratio, especially, a volume rate occupying in a three-dimensional structure of the artificial stone is important. According to our findings, the volume rate is clearly appreciable factor from the viewpoint of the luminescence performance along with a physical property of the artificial stone as a three-dimensional structure.

In the noctilucent/luminescent artificial stone of the present invention, a preferable volume rate of the transparent S* aggregate is determined to be 20 4 or more and 80 or less.

When thefilleris employed, though it ianot specifically limited, it is a desirable mode to control filler/light accumulation material and/or luminescent material by ultraviolet rays (by the volume ratio) into 100 or less.

S. Table 7 shows a decay time to brightness of 3 mcd/m 3 after irradiation at 200LX with the D65 commonly used light source to a saturated state, for samples consisting of; strontium aluminate base light accumulation material (G-300C) with an average particle diameter of 40 m as the light accumulaton average particle diameter of 40 uim as the light accumulation material, aluminiumhydroxide with an average particle diameter of 40 pm as the filler, quartz (a pulverized product) with a maximum particle diameter of 2.38 mm and an average particle diameter of 1.2 mm as the transparent aggregate, and MMA resin.

Table 7 Aggregate (quartz) volume rate 10 20 60 80 Time to 3md/m 2 6.5 12.5 13.5 12 (hr) From Table 7. it is understood that the above prescribed range enables the decay time to 3 mcd/ma to be 12 hours or longer.

Furthermore, in the noctilucent/luminescent artificial stone of the present invention, the luminescence performance can be improved by means of a combination with the transparency aggregate and the filler. Table 8 shows the above combinationa 15 The employed materials are; the transparent aggregate with a maximum particle diameter of 2.38 mm and an average particle diameter of 0 mm, the filler with an average particle diameter o of 40 pm, and the light accumulation material (strontium aluminace base: G 300C) with an average particle diameter of 40 pm. The volume ratios are; SO of a transparent aggregate,

S

of a MMA resin. 15 of the filler, and 5 of the light accumulation material.

Table 8 Brightness after one Deccay time t Transparent aggrogate Filler hour of irradiation by t lisht (incd/M 2 3mdm Aluminium, hydroxide 25 .83 I 3h3Orr (pulvrizput Silica 24.98 1 2h (pl eie rd c) Glass powder 23.71 Siia57-49 12hl15M Alunxinwm hydroxide 52.041h (pulverized Product) Gls powder 25.26 6 Calcium cabonate 38.14

S

Quartz, powder 18.68 4h45m *Commnhly commercial soda glass is used for glass.

Table 8 also shows results after irradiation at 2 0 Lx withi the V65 commonly used light~ source to a vaturated state. it is underatood that alumidnium hydroxide or silica as the filler ine preferable for qu~artz as the traparefley aggregate. arid that silica or aluinium~ hiydroxcide is preferable for glass.

In addition, it is understood that selection of such combinations enables the decay tim~e to 3 mcd/ M 2 to become 12 hours or longer.

It im grasped in Table 9 from a contrast of a light transmittance that the ef fectiva luminescence performanlce with is chess comjbinlationsB is seen irl case of lumnescent materials by ultraviolet rays.

Table 9 Transparent FAle bvmeaml Ditfusivily Perality aggregateFilrp eaiiy M Prabit Glass Aluminiurn hydroxide 44.14122.

(pulverized Glass powder 3. 321.

product) Calcium carbonate 21.8 2. Quartz powder 22.5 21.0 5.2 Table 9 shows the resultis on smpnles of the glass for the transpArent aggregate in Table 7. it it. well understood that the above Comzbination is preferable.

Au io described in the above, for instance, the present invention provides a noctilucen/lumileBcenc artificial stone including the transparent aggregate, the filler, and the light accumulation material along with a resin characterized by that the time to 3 mcd/m 2 after irradiation at 20OLx with the 065 commonly used light source to a saturated state is 12 hours at The artificial stone of the present invention having the euperior luminescence performance as described in the above may have various compositions as above and various manufacturing methods ao well.

About composition, an appropriate blending with function components such as the filler and trace components along with the above transparent inorganic aggregate and a reain may be considered for the artificial stone from the viewpoint of strength, weatherability, abrasion resistance, surface non-alipperiness, acolortone, incombustibility, andothermany functions.

of course, the transparent aggregate may occupy a whole amount of aggregate components as was described already, or inorganic aggregates of non-transparency may be used jointly as one part of aggregates, in the noctilucent/luminescent artificial stone of the present invention. However, even in the case of the combined use, the amount of the transparent aggregate is preferably 20 volt or more and 80 volt or less of the cast and hardened artificial stone in order to realize the superior performance like 12 hours or longer of the decay time to brightness of 3 mcd/m' after irradiation at 200Lx with the commonly used light source to a saturated state.

The total amount of the transparent aggregate and non-transparent aggregate is preferable to be similarly in a S* range of 20 vol% or more and 80 vol:or less.

It is needless to say that the inorganic aggregate including the non-transparent aggregate should have a maximum particle 20 diameter of 1/1.5 or less of the board thickness after cast and hardened and may be blended as a mixture with various particle diameters having a particle diameter distribution.

In practical, it is preferable that the inorganic aggregate "consisting of the transparent aggregate or the transparent aggregate and non-transparent aggregate has aparticle diameter distribution of a close-packing or the vicinity as is well known in a concrete engineering, and besides that the average particle diameter is 1/20 or more and 1/3 or less of the thickness of the cast and hardened artificial stone as is described above.

In addition, it should be a naturally considered point what kind of color tone and design inbright field wouldbe the obtained noctilucent/lumineacent artificial setne. An appearance of granite and marble is often aimed at because the product is hard to be obtained as they are natural and their color and luscer are beautiful. Inthis case, the color and luster is an important subject to determine a value of granite and marble. There are various sorts of colors in the natural granite and marble, such as complete black to white or red, and different degrees in the same color.

When giving a color to each kind of: an artificial stone.

a color reproducibility is a problem to obtain a product with a medium color tone. though, in case of a black product, for i instance, just black particulate matters of natural rocks have only to be used. In addition, it is not so easy to obtain the unique luster of the marble, even if the color is obtained.

It used to be difficult to give a luecer or a depth, even in the case of giving a color by a blended resin with dye or pigment.

I

As opposed to this, in the artificial scone of the present invention, transparent inorganic aggregates can be principally i employed. For instance, the transparent inorganic aggregate obtained by crushing quartz base natural-rock, glass, or fused silica can be employed.

By means of employing these transparent aggregates, the color of the artificial atone in a bright field can be controlled and allowed to have a depth and a luster owing to the existence of a quartz base granule component with transparency.

In addition, in the noctilucent/luminescent artificial stone of the present invention, the much finer filler than the aggregate is employed along with it, for instance, preferably, with a particle diameter of 0 .1 mm or less and an average particle diameter of 30 Mm or more and 70 pm or less. The filler includes natural or various kinds of artificial materials preferably such as aluminium hydroxide, silica, andglasspowder, for instance.

These inorganic fillers have much finer particle diameter than the above aggregates, and contribute to properties. uch as hardness, softness, and surface non-lipperinessof the obtained artificial stone, while they invade into spaces among the inorganic aggregates and locato to fill the spaces among grains.

As a part of blend for these fillers, components such as manganese dioxide, titanium dioxide, zirconium silicate, and iron oxide maybe added for adjusting a color tone; and antimony trioxide, boron compound, bromine compound and the like for giving a flame retardance.

n addition, an inorganic antimicrobial agent may be combined. The artificial stone of antibacterial activity is useful for a bathroom. floor of rest rooms, wall, and handrail, for instance. It is also useful in a medical facility, a food processing facility, and the like.

As aninorganic antimicrobial agent, thereare silver, zinc, and copper base inorganic materials. for instance.

Resins can be selected from the wide range as described above.

The resin includes, for instance, an acrylic resin, a methacrylic resin, an unsaturated polyester resin, an epoxide resin, a silicone resin, a silicone rubber, and the like. In these, a methacrylic resin, an epoxide resin, the mixture, or the copolymerization resin is shown to be preferable.

An organic pigment such as an azo base, a phthalocyanine base, dye. etc, may be blended to these resins in order to adjust the color tone.

In addition, a light stabilizer or a fire retardant may be included.

Resin components contrAbute to wrapping the aggregate and the filler which are component for forming a skeleton of the artificial stone and bonding the whole, and have a function for giving an elasticity or a tensile strength to the completed artificial stone.

About resin component, the volume rate may be about 70 or less, but more preferably in practical 25 vol% or more and 3 5 vol% or less when characteristics uchau strength, durability, ~natural rock-like appearance, and tint, or non-slipperiness and the like for the artificial stone are considered.

The artificial stone product with an excessive resin component appears plastics, and the artificial stone becomes merely nominal. When the resin component is excessively little.

Ra** the product becomes fragile and not suitable for use though the appearance of the product approaches to a natural tone.

About resin components in the present invention, every kind of resin can realize the artificial stone having the superior and essential performance for the noctilucent/luminescent artificial stone. However, a mechacrylic resin, particularly MMA (methyl methacrylate) resin is preferably employed as a main component, in the artificial Stone for the use to which weatherability, chemical resistance, hardness, abrasion resistance, transparency, depth of color tone and the like are demanded.

Instead of the main composition of the artificial stone consisting of the inorganic aggregate, the inorganic filler, and the resin as described above, the flexible composite with high hardness which have been already proposed by the present inventors can be composed for the artificial stone similar to the noetilucent/luminescent artificial stone.

That is an artificial stone with a surface hardness of 400 9 ormorewichVickerahardness (JISZ2244) andaradiusof curvature of R25mm at which bending is possible without damaging for a board of 3 to 15 mm thick.

In the composite, the inorganic components including the inorganic aggregate can occupy 50 vol% or more of the total and organic components such as resin can be less than 50 vol%. A main component of the organic component is a metbacrylate resin.

SMore concretely, it is shown as adenatured MMA resinwith blending polymethylmethacrylate (PMMA) and one ormore materials selected from methyl methacrylate (MMA) monomer, 2-ethylhexyl methacrylate monomer, 2-ethylhexyl acrylate monomer, 2-ethyl pentyl methacrylate monomer. butylmethacrylate monomer, and cyclohexyl methacrylate monomer.

Table 10 shows the light accumulation luminescence performance namely the noctilucent property of the artificial stone obtained with each kind of resin.

The employed materials are; the aggregate of pulverized quartz with a maximum particle diameter of 2.3 8mm and an average particle diameter of 1.2 mm. a filler of aluminium hydroxide with average particle diameter of 40 m, and a strontiumaluminate base light accumulation material with an average particle diameter of 40pm The compositions are S0 volof the aggregate, 13 volt of the filler, S vol lof the light accumulationmaterial, and 30 vol% of the resin. The thickness of the cast and hardened artificial stone is 5 mm.

*e ea a.

9 e *o Table Brightness after one hour Resin of irradiation by light 3mcd/m 2 (mcd/m 2 3mcd/m MMA resin 58.72 12h Unsaturated polyester (DAINIPPON INK AND CHEMICALS, 57.85 1 INCORPORATED "FG208") Degeneration MMA resin 57.98 11h45m (Mitsubishi Rayon Co., Ltd. "XD7005") *Light irradiation irradiation at 200Lx with D65 for minutes (more than saturation time) In addition, in the noctilucent/luminescent artificial stone of the present invention, the above transparent aggregate may be baked or coated at a room temperature with a noctilucenct light accumulation material or a luminescent material by 10 ultraviolet rays.

In case of a coating with baking, fine particles with a diameter of several pm to several dozens pm, for instance, to 50 pm, more preferably 20 to 40 pm maybe coated on the surface of the transparent aggregate particles. More concretely, the coating can be carried out with a baking at a high temperature of around 120 to 1200 °C.

The luminescent coating substance may include various kind of light accumulating substances or light emitting substances by ultraviolet irradiation such as scrontium aluminate and zinc sulfide.

As for a baking method, various conventional methods may be employed. For instance, the transparent inorganic aggregates are mixed in a dispersed solution of particles of light accumulation materials such as strontium aluminate or the paste, are dried and baked.

A coating at a room temperature can be done in the above dispersion solution or a paste with a transparent sticky substance (binder).

The nocTilucent/luminescent artificial stone of the present invention can be made with casting and hardening a liquid or floating mixed raw material or composition.

Casting and hardening can be done with a casting formation, a compression molding, and a stepless belt formation.

A compression molding, for instance, is done in the followingway; casting, beforehand, anecessary quantityof the composition for the eompletedproduct such as inorganic aggregate, filler, and resin components into a drag as a horizontal molding-flask; matching a cope; and compression molding, for S*instance, with a bearing stress of 5 to 100 kgf/cm 2 At a compression of this molding, the composition can be heated to a temperature of roughly 80 to 180 oC for 5 minutes to several hours.

In addition, in the compression molding with heating, oscillation can be given to the molding-flask along with compression to improve a flowability of the above material in the molding-flask.

S Of course, a shape for the real product with the artificial stone in the present invention does not need to be limited to a flat board. It maybe an induction projection for an eyesight handicapped person, have a surface with projections, or be composed a a stepped shape. Many other shapes may be considered.

In the present invention, a rough- urfaced processing may be done on the surface of a cast and hardened compact.

As a method for this purpose, first of all, a selective removal method of a resin component is adopted. In other words, skin surface processing with squirting highly pressurized wacer onto a surface of a compact after removing from a molding-flask, for instance, is effective. That is water-jet machining.

In this water-jet machining, many conditions are selected; such as a surface hardness and a surface strength of the processed material, and a hydraulic pressure, a diameter of an ejection nozzle, and a distance between a material surface and a nottle outlet for forming a predetermined depthof grooves on the surface in uniformity coping with these properties. It is not defining, but, for instance, a hydraulic pressure of about 100 to 1500

S.

l. /cm 2 can be usually employed for a nozzle of around S to SO mm high.

There is no limit in particular about a nozzle for squirting .***highly pressurized water and the system. All kinds of nozzles are employed.

By means of water-jet machining, surface roughening is realized and the artificial stone, for instance, with 25 non-slipperiness and a deep touch of a material is produced- Besides, what should be emphasized in the present invention, is no clouding of a color of the artificial stone by means of water-jet machining.

The noctilucen/luminescent artificial stone of the present invention needs to provide non-slipperiness when an application, for instance, forapassage or a step in which refuge induction is needed at the dark background atmosphere such as a road or a platform and a step in a station in a power cut is considered. Water-jet machining can give such nonslipperiness to the artificial stone.

As for giving the non-slipperiness, the present inventors have proposed in other invention an artificial stone; fundamentally including an inorganic aggregate and a resin and having a convexeconcave surface in which inorganic aggregates are exposed, wherein an average depth of the surface grooves are 0.02 mm or more and 1.0 mm or leas, particularly of 0.05 mm or more and 0.8 mm or less.

By the above invention, the followings are enabled to be provided; anon-alipperyartificial atone including an inorganic aggregate and a resin and having a convexoconcave surface in which inorganic aggregates are exposed, being characterized by that a skid resistance value BPN(ASTM E303) is 60 or more at a wetting face and 20 or more at an oil face. and a non slippery artificial stone characterized by that a skid resistance value BPN is or more at a wetting face and 35 or more at an oil face; a non slippery artificial stone including an inorganic aggregate and a resin and having a convexoconcave surface in which inorganic aggregates are exposed, being characterized by that a skid resistance value C.S.R. (JISAS 705 and JI A 1454 are referenced) is 0.8 ormore at a wetting face formen's shoes anda non slippery artificial stone characterized by that a skid resistance value C.S.R. is 0.45 or more at an oil face; a non slippery artificial stone including an inorganic aggregate and a resin and having a convexoconcave surface in which inorganic aggregates are exposed, being characterized by that a skid resistance value C.S.R.B. (JIS A 5705 and JIS A 1454 are referenced) is 1.4 or more ata wetting face fora barefootand anon alipperyartificial stone characterized by that a skid resistance value C.S.R.B.

is 0.8 or more at a wetting face with soap for a barefoot; and a non slippery artificial stone including an inorganic aggregate anda resin andhaving a convexoconcave surface inwhich inorganic aggregates are exposed, being characterized by that a surface contactangleofdistilledwater is45 to 7degreeon an average.

A scraped amount from the surface of the artificial stone by water-jet machining is about 10 cm 3 /m 2 from a view point of S. a surface concave groove depth of 0.02 to 1.0 mm as a general rule of thumb, while it varies depending upon a sort of inorganic aggregate and resin, their composition rate. and the formation condition. and is decidedappropriatelyconsidering thesepoints.

In a case of the artificial stone with a use of quartz as an inorganic aggregate and MMA resin, for instance, the measure can be 30 to 38 cm/m' for the average surface concave groove depth of 0.05 mm and 80 to 92 cm/m 2 for the average surface concave groove depth of 0.2 mm.

An effluent treatment for water-jet machining is easy in comparison with an etching method which employs an organic solvent.

Of course, Parts of the surface can be removed, if needed, bymeas of processing inanarganic solvent, softeningormelting a resin component.

The organic solvent used in the above purpose may be selected in correspondence with a resin component. It includes, for instance, a halogenated hydrocarbon such as ethylene chloride.

dichloromethane, and chloroform; carboxylic acid and the ester compound such as acetic acid anhydride, ethyl acetate, and butyl acetate; or acetone, tetrahydrofuran, DMF, and DMSO.

Convexoconcaves on the surface of the artificial stone compact can be formed by means of removing a softened or melted resin component from the surface after dipping the compact in these organic solvent or spraying or flowing these organic solvents on the compact.

The softened resin component may be scraped off from the surface with a wire brush or other scraping means.

In addition, particles may be exposed to the surface of the product as sections by means of grinding the surface and as the result, breaking the surface partially. Surface texture with unique depth, luster, and gloss are realized hereby. This is caused by a unique phenomenon of reflected light.

A means for surface polishing is not limited in particular.

It can be carried out with a tool such a a grind stone, an abrasive cloth, and an abrasive belt, or an abrasive such as a buffing compound and a rubbing compound.

As abrasives, the followings are appropriately employed; diamond, boron carbide, corundum, alumina, and zirconia for mainlygrinding, and tripoli, dolomite, alumina, chromium oxide, and cerium oxide for mainly polishing.

S The surface can be roughened, after being polished in the above method.

The noctilucenc/luminescent artificial atone product auited for various uses which includes products with or without non-slipperiness, is to be provided in the present invention with various manufacturing methods such as various forming methods, or various processing methods like cutting, scraping.

laminating, and etching.

Various members and formations, for instance, for decorations for the night, buildings and public works such as direction indicators and guides for location by luminescence in a dark atmosphere, anddisasterprevention, are tobeprovided It is needles to say that the above products are utilized as a luminescent member or an optical formation for using no energy or saving energy.

By the way, there are several points which should be paid 9 attention to, in the present invention.

It is that the following products are included in the noctilucent/luminescent artificial stone of the present invention; a product, for instance, as is shown in Fig. i.

25 consisting of the cut out artificial stone (12) as a thinner board than the molded board from the molded artificial stone (11) after cast and hardened; or the artificial stone (13) which was further processed on the artificial stone (12).

In addition, it is natural, but it is needless to say that acutoutartificial stone (15) n a sheet form from anartificial stone (14) which was carried out with non slip processing on the molded artificial stone (11) as is shown in Fig. 1, is also included in the artificial stone of the present invention.

The present invention also provides a formation in which the noctilucent/luminescent artificial stone is laminated as a surface material, or a formation in which the noccilucent/luminescent artificial stone is composed as a part of the surface.

As for a lamination composition, an integrated body is illustrated, which is composed of; the noctilucenc/luminescent artificial stone of the present invention as a surface material; and a resin plate, a metal plate, a stone, a ceramic plate or a cement plate on the back, which is laminated with an adhesive, oooe°: or bonded mechanically with metal fittings or fit bonds.

The followings are also illustrated: an integrated product 4*9 in which the noctilucent/luminescent of the present invention is composed with an inorganic material such as a mortar concrete *or a gypsum, or a resin as a backing material by means of casting *9S* and molding after the artificial stone was cast and hardened or semi-hardened; a product obtained by placing a tile, a gypsum oo plate, ametalplate. andglass at a predetermined siteand casting 25 and hardening the artificial stone; and a product obtained by *e* molding the artificial stone of the present invention, and in the semi-hardened condition on the back side. placing a tile.

a gypsumplate, ametalplate, andglass at a predetermined site.

and hardening it with compression.

The following various products, as are shown in Fig. 2 (A) for instance, maybe included in the laminated composition; not only a product in which the noctilucent/luminescent artificial stone of the present invention (21) is entirely laminated with other sort of materials (22) but also a product partly laminated in a gridiron shape like Fig. 2 and a product laminated in a multi layer.

In addition, as for a product a part of which the noctilucent/luminescent artificial atone composes, the following appropriate constitutions are to be considered; a product in which the artificial stone similar to the noctilucent/luminescent artificial stone is placed through joints; a product in which the noctilucent/luminescent artificial atone (31) is arranged at a part of step of stairs as is shown in Fig. 3; a product as is shown in Fig. 4 in which an artificial stone, concrete materials, tile materials or the 0..

like without luminescence is molded with implantation in a predetermined place of the noctilucent/luminescent artificial s stone (41) of the present invention as a base material.

Manufactured examples of the noctilucent/luminescent artificial stone of the present invention are described below.

Of course, the present invention needs not to be limited by the following examples.

<Example 1> The materials are prepared to have the following composition, employing the aggregate of pulverized quarcz (pulverized product) with a maximum particle diameter of 2.5 mm, an average particle diameter of 0. 5 mm, MMA resin for a resin. and the filler of aluminium hydroxide with a particle diameter of 0.1 mm or less; Ouartz aggregate 47 vol% Resin 29 vol% Aluminium hydroxide 10 vol% (average particle diameter of 40 pm) Light accumulation material 13 volt (strontium aluminate base ;G-300C) (average particle diameter 40 pm).

Each weight ratio was as follows.

Quartz aggregate 59 wt% 15 Resin 15 wtr Aluminium hydroxide 9 wt% Light accumulation material 14 wt% Avery small amount of a silane coupling agent and a hardening :0**0 agent was also blended.

20 The mixture of the aggregate and the others as a syrup of MMA resin was cast into a molding-flask and was molded with compression to a board of S mm thick.

The obtained artificial stone was irradiated by light at 200Lx with the D65 commonly used light source for 60 minutes 25 (more than saturation time). The brightness afcer one hour of irradiation was 27.86 mcd/m 3 and the decay time to 3 mcd/m 2 was 14 hours and 30 minutes.

<Example 2> The artificial stone provided in Example 1 was removed from the mold and the surface was roughened by means of squirting water-let of 1500 kg/cma through a nozzle 30 mm distant from the surface. The artificial stone with surface concave grooves of 0.2 mm deep on an average hereby.

For the artificial stone, the bending strength was 90 N/cm.

the hardness was 7 with Mohe' hardness of a quartz aggregate, and the water absorption was zero.

In addition, any abnormality was not recognized by an acid and alkaline resistance test with immersion in an aqueous solution of 3 I hydrochloric acid for 8 hours and of 3 sodium hydroxide for 8 hours respectively.

Non-slipperiness of this artificial stone was excellent 15 as follows; C.S.R. (men's shoes) 0 Wet plane 0.871 0* Oil plane 0.629 C.S.R.B (bare foot), *ooee0 S 20 Wet plane 1.465 Soap plane 1.223 The luminescence performance of the artificial stone to which non-slipperiness was given, was evaluated in the same method as Example 1 to confirm that the decay time to 3 mcd/m 2 25 was 14 hours 15 minutes and about the same value as Example 1.

As described indetail intheabove, in thepresent invention, the improvement of the luminescence performance such as a longer 47 continuation time of a light accumulation luminescence is enabled, and besides giving physical properties of extremely high and functional qualities such as strength, surface hardness, abrasion resistance, weatherability, and non-slipperiness are also enabled by a control of the structure of the artificial stone.

Throughout this specification and the claims, the words "comprise", "comprises" and "comprising" are used in a non-exclusive sense, except where the context requires otherwise.

It is to be clearly understood that any reference herein to a prior art publication does not constitute an admission that the document forms part of the common general knowledge in the art in Australia or in any other country.

o *e e*o H Shery IM',Keep\ P4 15R3 doc 4 10/01

Claims (16)

1. An artificial stone including a transparent aggregate and at least one kind of a light accumulation material and a S luminescent material byultraviolet raysalongwith a resin being characterized by that luminescenceperformance of the artificial stone is higher than that of the included light accumulation material and/or luminescent material by ultraviolet rays per se.

2. The artificial stone according to claim 1, being characterized by having high luminescence performance in a lower filling factor (volt) of the artificial atone than a maximum filling factor (vol%) of the included light accumulationmaterial and/or luminescent material by ultraviolet rays per se. 5 3. Theartificial stoneaccordingto claim 1 or 2, wherein a particle diameter of the transparent aggregate is 0,1 mm or more and 1/1.5 or less of a thickness of the artificial stone after cast and hardened. S5oo

4. The artificial stone according to claim 3, wherein the 20 particle diameter of the transparent aggregate is 0.3 mm or more. S. The artificial stone according to claim 4, wherein an average particle diameter of the transparent aggregate is 1/20 or more and 1/3 or less of the thickness of the cast and hardened artificial stone. 2 25

6. The artificial stone according to any one of claim 3 to 5, wherein the transparent aggregate have an irregular surface configuration.

7. The artificial stone according to any one of claim 1 to 6, wherein each average particle diameter of the light accumulation material and/or the luminescent material by ultraviolet rays is 10 pm or more and 300 pm or less.

8. The artificial stone according to claim7, wherein the average particle diameter is 40 pm or more and 150 pm or less.

9. The artificial stone according to any one of claim 1 to 8, being characterized by including an inorganic filler with a particle diameter less than 0.1 num.

10. The artificial stone according to claim 9, wherein an average particle diameter of the inorganic filler is 30 pm or more and 70 pm or less.

11. The artificial stone according to any one of claim 1 to 10. wherein a volume rate of the transparent aggregate is 20 t or more and 80 or less.

12. The artificial stone according to claim 11. wherein a volume ratio of the filler to the light accumulation material, the luminescent material by ultraviolet rays or the mixture of the both, is 0 or more and 100 or less. defined as filler/light 20 accumulation material and/or luminescent material by ultraviolet rays.

13. The artificial stone according to any one of claim 1 to 12, wherein the transparent aggregate is quartz or rock crystal and the filler is aluminium hydroxide or silica.

14. The artificial stone according to any one of claim 1 to 12, wherein the transparent aggregate is glass and the filler is silica or aluminium hydroxide. 50 The artificial stone according to any one of claims 1 to 14, characterized by including a nontransparent aggregate along with the transparent aggregate and by that its particle diameter is 1/1.5 or less of a thickness of the artificial stone after cast and hardened and a total volume rate of the transparent aggregate and the nontransparent aggregate is 20% or more and 80% or less of the artificial stone.

16. The artificial stone according to any one of claims 1 to 15, wherein a time from a saturated state after irradiation at 200Lx with a D65 commonly used light source to brightness of 3 mcd/m 2 is 12 hours or longer.

17. The artificial stone according to any one of claims 1 to 16, wherein the artificial stone is constituted with lamination as a surface material.

18. The artificial stone according.to any one of claims 1 to 17, wherein the artificial stone is constituted as a part of the surface.

19. An artificial stone substantially as herein 20 described in any Example. Dated this 4th day of October 2001 DOPPEL CO., LTD By their Patent Attorneys 25 GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia o H:\SheryIM\KCeP\P435R3.doC 4,1/01