SHATTERING ARTICLE, MOULDING COMPOSITION AND METHOD OF PRODUCING A SHATTERING ARTICLE

Abstract: A shattering article comprising a composition consisting of filler material, consolidated binder, and optionally additives, wherein the filler material is a powder consisting of i) fine particles having a particle size from 1 mu m to 50 mu m, and ii) coarse particles having a particle size from 50 mu m to 1500 mu m, having a fine/coarse filler ratio from 5 % to 60 % by volume; and a moulding composition and methods for the production of such a shattering article.

Description: SHATTERING ARTICLE, MOULDING COMPOSITION AND METHOD OF PRODUCING A SHATTERING ARTICLE DESCRIPTION 1. BACKGROUND OF THE INVENTION The present invention relates to a shattering article particularly, but not restricted to, a shooting target such as clay pigeons comprising filler material, consolidating binder, and optionally additives; a moulding composition comprising a mixture of filler material, binder, and optionally additives; and methods of producing shattering articles from such moulding compositions. The Technical Field Shattering articles, particularly flying shooting targets, are commonly formed in a saucer-like shape ideally provi¬ ding a stable flight in the air over a considerable dis¬ tance. They exhibit a relatively fragile or frangible structure which is able to break and fail to clearly indicate a hit. These known shooting targets, however, are encumbered with serious drawbacks. One drawback is that the brittleness of the target mate¬ rial is changed during storage by absorption of water or by variations in temperature whereby - the shape of the target is changed by softening of the material; - the flight is unstable due to deformation of the targe ; - the target does not disintegrate into shattered frag- ments; or - the target does not exhibit an indication of a hit upon impact by a projectile or pellet. Another drawback is that one or more constituing materials are toxic and in addition are not decomposable or only very slowly decomposable in the environment whereby the shattered fragments become dangerous to animals, if eaten. Still another drawback is that one or more of the consti¬ tuting materials may harmfully pollute the soil and/or ground water. Also, these known targets are relatively expensive. Therefore, there is a need to provide a shattering article which overcomes these drawbacks. Prior Art Disclosures US Patent No. 3 840 232 published 8/10-1974 discloses a frangible flying target consisting of 35% to 70% by weight of elementary sulfur and from 65% to 30% by weight of a finely divided inert filler material consisting of lime- stone dust, said frangible flying target being shatterable upon impact by a single pellet. In a particular embodiment of a degradable target, a dimensionally unstable material such as betonite clay is added in the amount of 1-10% by weight of limestone. This flying target has a number of disadvantages, e.g. that low sulfur content results in a stiff liquid mixture of limestone and sulfur which is difficult to process and which requires hydraulic pressed forms which are difficult to handle, thereby increasing the manufacturing costs. German Offenlegungsschrift No. DE-2439247-A1 published 15/1-1976 discloses a frangile shooting target comprising 50-90% sulphur; 9-40% inert filler such as sand, concrete, clay, and silica aggregates having a sieve size from about 18 am to about 250 urn; 1-10% plastiziser, preferably poly- styrene; and optionally 0.5-5% maleinic acid as fire inhibitor. This shooting target has a number of dis¬ advantages. Thus, in order to control the brittleness of the material, the target material contains a platiziser such as polystyrene which can only be degraded very slowly in the environment, producing monomer styrene which is toxic. US Patent No. 3 884 470 published 20/5-1986 discloses a saucer-shaped, thin-walled, frangible target for use as a flying target formed or moulded from a sulfur composition consisting of mainly sulfur with about 0.05-1% strength increasing additives, such as n-decane, naphtalene, bisphenyl, ethane dithiol, lignin sulfonate, sodium sul- fide, or iron sulfide. Such a target has a number of dis- advantages. Thus, in order to control the brittleness of the material, it contains additives which are harmful to the environment, and the predominant components of such additives are expensive. US Patent No. 4 124 550 published 7/11-1978 discloses a clay pigeon used as a target in trap shooting which pigeon is produced by molding a composition comprising a low molecular weight thermoplastic resin such as petroleum resin, polystyrene or polyterpene resin; a high molecular weight thermoplastic resin such as polyethylene, poly¬ propylene or polystyrene; or an inorganic powdered filler selected from the group consisting of calcium carbonate, talc, clay, alumina white, mica powder, aluminium sulfate, barium sulfate, gypsum, calcium sulfite, lithopone, pumice powder, glass powder, zinc white, magnesium carbonate, metal powder, asbestos powder and titanium oxide with a particle size in the range from 0.01 to 500 urn. This clay pigeon has the disadvantage of being non-degradable in the environment, difficult to process, and requiring relative¬ ly expensive thermoplastic binders. US Patent No. 4 568 087 published 4/4-1986 discloses a non-toxic clay pigeon produced from a mixture consisting essentially of plaster (CaSO.,^H^O), water in excess for setting the plaster, calcium carbonate, and one or more additives such as surfactants, organic binders, release agents, set-controlling agents, and brittleness-promoting agents; and optionally fly ash, and heavy spar; by subjec¬ ting said mixture to compression in a mould heated to a temperature of 100 °C to 160 °C; said clay pigeon alleged- ly being non-toxic to animals, non-polluting of the environment, capable of withstanding mechanical impacts during transport and from throwing apparatus, and sufficiently frangible to break when hit by pellets. This clay pigeon has the drawbacks of a tendency to change in shape, not to break in part or produce a visual indication of a hit presumably caused by inadequate removal of the excess process water, and the material has an open porosity which results in absorption of water thereby changing the weight and material strength of the pigeon. Further, it was found that heavy metals were released from clay pigeons comprising fly ash. US Patent No. 4 623 150, published 18/11-1986 discloses a projectable and frangible target comprising an inert filler component such as limestone, gypsum, anthracite, sand, and mixtures thereof, in an amount between about 85% and about 96% by weight; and a solidified naturally occurring water soluble binder component such as starches, dextrines, gums, glues, lignins, waxes, alginates, col¬ loidal silica, silicates, phosphates, aluminates, clays, and mixtures thereof, in an amount between about 4% and 15% by weight; said binder being capable of forming ag¬ glomerates or moulding granules with said inert filler component without heating. The moulding granules are com¬ pressed to the desired form without application of heat sufficient to alter the binder, and the compressed form of granules is then dried by evaporating the solvent to form a solid binder. This target has the drawback of being porous which results in the absorption of water thereby changing the weight and strength of the target. Further, in the preparation of these targets, the preparation of the agglomerates or moulding granules is critical whereby the target properties such as appearance, green strength (i.e. the strength immediately after moulding, but prior to drying), frangibility, dimension stability, temperature sensitivity, etc. are difficult to control. US Patent No. 4 921 250 published 1/5-1990 discloses a frangible article for the use as a target, or as a projec¬ tile, comprising a mixture of sand and a decomposable bin- der which is formed and cured to a desired shape, said binder comprising by weight 20-60% grain flour; 5-30% salt; 0.5-5% petroleum lubricant; and water; said article allegedly being bio-degradable, non-toxic, resistent to moisture absorption, and having a consistent frangibility characteristic. This frangible article has the disadvan¬ tage of absorption of water resulting in degradation and change of physical properties of the article. 2. DISCLOSURE OF THE INVENTION Object of the Invention It is the object of the present invention to provide a shattering article which exhibits a controllable britt¬ leness; particularly a controllable brittleness at a low binder content. It is another object to provide such an article which can be produced using cost effective materials. It is still another object to provide such an article com¬ prising materials which are easy to process and which are not harmful to the environment. Solutions According to the Invention According to the invention, these objects are fulfilled by providing a shattering article comprising the constituents defined in the introductory portion of claim 1 and charac¬ terized by the features of the characterizing portion of claim 1, wherein the filler material comprises at least two powdery materials, including i) a fine filler material consisting of fine particles having a particle size in the range from 1 urn to 50 urn, and ii) a coarse filler material consisting of coarse par- tides having a particle size in the range from 50 urn to 1500 urn, having a fine/coarse filler ratio in the range from 5% to 60% by volume, whereby it is obtained - that the composition of the filler material consists of fine particles having a particle sizes sufficiently small to partially fill up the void between the coarse particles, and - that the volume of fine filler material can be chosen in a range which allows control of the available volume of the consolidated binder, thereby ensuring that the shattering article exhibits a controllable brittleness; particularly a controllable brittleness at a low binder content. It has surprisingly been shown that by reducing the amount of binder, the strength and brittleness of a shattering article can be maintained if the filler material used in addition to a coarse filler material also comprises a fine filler material. Further, by varying the volume of fine filler material with respect to the volume of the total filler material, a means of controlling the volume available to the consoli¬ dating binder and consequently the brittleness of the con¬ solidated composition can be obtained. Further, because the consolidating binder is the most costly component, the material costs can be reduced due to the possibility of using cheap filler materials in increased amounts. Another advantage is that the consolidating binder and filler materials can be chosen among materials which are not harmful to the environment. Even if the shattering article should comprise a consoli¬ dating binder material which is harmful e.g. to the environment, the small amount of consolidating binder may be acceptable under special circumstances. Preferred Embodiments "Filler material" Suitable filler materials are known in the art including finely divided materials such as clay, limestone, gypsum (calcium sulfate), anthracite, fine sand; further filler materials include the filler materials disclosed in e.g. US Patents Nos. 4 124 550 and 4 623 150, the contents of which are hereby incorporated by reference. The fine and coarse filler materials are selected with respect to the available filler materials, their particle size, and the required strength and brittleness of the shattering article. According to the invention, the fine/coarse filler ratio is in the range from 5% to 60% by volume depending on the desired amount of consolidating binder. However, if it is desired to reduce the amount of binder, it is preferred that the fine/coarse filler ratio is chosen in the range from 10% to 30% by volume, preferably about 25% by volume. An optimal fine/coarse filler ratio can be determined for the starting materials by experimentally measuring the tap density at different fine/coarse filler ratios. It is pre¬ ferred that the fine/coarse filler ratio is such that the density of the filler composition is about its maximum. Thus, for given starting materials having known fine fil¬ ler particles sizes and coarse filler particle sizes, a person skilled in the art would be able to choose an optimal fine/coarse filler ratio providing a high density of the composition corresponding to a desired brittleness. In a preferred embodiment, at least 95% of the fine filler particles have a particle size from 10 μm to 20 μm, preferably an average particle size of about 12 μm, and at least 95% of the coarse filler particles have a particle size from 100 μm to 300 μm, preferably an average particle size of about 200 urn. It is preferred that the filler material and the optionally additives constitute from 20% to 95% by weight of the composition. The particle sizes of the fine and coarse filler materials can be obtained by methods known in the art including sieving and sedimentation. "Fine filler material" According to the invention, the fine filler material is a powdery material which consists of fine particles of suf¬ ficiently small particle sizes compared to the larger coarse filler particles and optionally powdery additives, so that the fine particles can fill up a substantial part of the void between the larger particles while leaving minimum space for the binder. It is preferred that the fine filler material is a ma¬ terial having lubricating properties whereby the larger particles can be compacted without applying large com¬ pression energies; and whereby the composition material comprising the mixture of filler material, binder, and optionally additives becomes more fluid and subsequently obtains an improved floatability which ensures better processing properties. Further, the presence of fine particles ensures that a smoothly and easily floating moulding composition is ob¬ tained, and that the tendency of sedimentation of the lar¬ ger sand particles in the melted binder is reduced. In a preferred embodiment, the fine filler material is chalk or talc. "Coarse filler material" The coarse filler material is a powdery material of rigid particles which may be porous or non-porous. It is pre¬ ferred that the coarse filler material is non-porous whereby the surface area is reduced and subsequently the necessary amount of binder is reduced. In a preferred embodiment, the coarse filler material is sand, ash, or gravel. Any sand or gravel having a particle size distribution from 50 urn to 1500 urn may be used. It is preferred to use washed and dried quartz sand whereby a neutral effect to the environment is obtained. Alternatively, ash in form of ash from the combustion of straw in combined power and heating plant stations may be used. The ash consists of K-silicates with uncombusted carbon which then can be recirculated to the plants providing a positive effect to the environment. Further, the ash contains micro pores which increases the surface area and subsequently requires more binder than unporous coarse filler materials. "Consolidated binder" The consolidated binder is selected among binding mate- rials which can consolidate a mixture of the powdery filler material, binder, and optionally additives to the suitable strength and brittleness. Binding materials are known' in the art including curable materials which are cured by methods such as a) hydratization, e.g. gypsum and cement; b) evaporation of solvent, e.g. one-component adhesives, starch or modified starch dissolved in water; c) polymerization, e.g. epoxides; and d) melting/solidification; e.g. pitch and petroleum resin based clay pigeons; further binding materials include the binding materials disclosed in e.g. US Patents Nos. 4 124 550 and 4 623 150, the contents of which are hereby incorporated by referen¬ ce. Binders cured by melting/solidification processes are pre- ferred for the purpose of mass production because a mel¬ ting/solidification process can be carried very fast in a temperature cycle around the melting point of the mixture. Meltable binders include low temperature melting binder melting from 50 to 200 °C, e.g. alkyd resin, single component protein based glue, sodium benzoate, polyethylene glycol, polyvinyl acetate, polyvinyl alcohol, petroleum resin, paraffin vax, sucrose, sulfur, pitch; and high temperature binders, e.g. clay. In a preferred embodiment, the binder is sulfur, pitch, petroleum resin, phenolic resin, paraffin wax, or sucrose. A particularly preferred binder is sulfur which is cheap water insoluble, harmless to the environment, as it can be metabolized by sulfur bacteria which are naturally found in nature. It is preferred that the binder is 5% to 80% by weight of the composition, preferably , from 20% to 45%, most preferred from 29% to 33%. "Possible additives" Examples are additives which may modify or add some particular features to the shattering article or the composition from which it is made. Other additives include color pigments such as carbon black and fire inhibitors such as various ammonium hydrogen phosphates. In a preferred embodiment, an optional additive consists of a color pigment, preferably a high surface area carbon black powder, in a concentration in the range from 0.5 to 2%, particularly about 1% by weight whereby the article is provided with a deep black color making it more visible against the sky when it is implemented in form of a shooting target. In another preferred embodiment, an optional additive con¬ sists of a fire inhibitor, preferably ammonium hydrogen phosphate, in a concentration in the range from 2% to 5%, particularly about 3% by weight whereby the the risk of setting the shattering article on fire is avoided, i.e. either during storage or upon a hit by a pellet. "Shooting targets" The shattering article may take any suitable form serving its purpose. In a preferred embodiment, the shattering article is in form of a shooting target such as a clay pigeon. Moulding Compositions In another aspect of the invention, there is provided a moulding composition for the production of a shattering article as defined in claims 12-21 whereby the effects and advantages of the shattering article according to the invention, as described above, can be obtained. The binder or optionally additives may be in any suitable liquid or solid form. Mouldingr Methods In a further aspect of the invention, there is provided a method of producing a shattering article, particularly a shooting target such as a clay pigeon comprising the steps of providing a moulding composition containing a binder; treating the composition in order to melt the binder; shaping the melt in a mould under pressure, extruder, or a transfer press; and allowing the melt to solidify; wherein the moulding composition is a moulding composition accord¬ ing to any one of claims 12-21. It has been shown that a moulding composition according to the invention has a number of advantages when it is melted and subsequently shaped in compression or extrusion pro¬ cesses. Thus, the moulding composition has suitable lubricating properties whereby the larger particles can be compacted without applying large compression energies; further, the moulding composition has improved float- ability which ensures better processing properties than known compositions; and the tendency of sedimentation of the larger sand particles in the melted binder is reduced. In still a further aspect of the invention, there is provided a method of producing a shattering article, par¬ ticularly a shooting target such as a clay pigeon compri¬ sing the steps of providing an homogeneous, dry, moulding composition containing a binder; melting and shaping the composition in a mould under pressure and simultaneous application of ultrasonic energy; and allowing the melt to cool; wherein the moulding composition is a moulding com¬ position according to any one of claims 12-21. When simultaneously applying pressure and ultrasonic energy dissipation, it was surprisingly observed that the lubricating properties of the fine filler material were not required. Further, it was observed that the amount of binder could be less than the perculation limit of 25.6% by volume to 6.55% by volume of binder, thereby obtaining about 75% reduction of the amount of binder. Definition of Expressions In the context of the present invention, the expression "shattering article" is intended to designate an article capable of disintegrating into shattered fragments upon impact of a projectile or a pellet, and at the same time capable of withstanding the vigorous action required to project it for a considerable distance in the air. Shat¬ tering articles include shooting targets known as "clay pigeons" used for trap and skeet shooting. 3. BRIEF DESCRIPTION OF THE DRAWING Fig. 1 shows experimental tab densities (D) versus volume chalk/cyclone sand ratios (%). 4. DETAILED DESCRIPTION "Control of brittleness" For the control of the brittleness of the shattering art¬ icle produced from given starting materials, the optimal fine/coarse filler ratio by 'Volume of the fine and coarse filler material corresponding to the desired amount of consolidating binder and consequently the desired brittle¬ ness of the article material, can be determined from a series of tab densities measured at different fine/coarse filler ratios. The tab density can be determined by transferring a mix¬ ture of fine and coarse filler material to a graduated glass cylinder until a loose volume of 10 ml. The glass cylinder is then tapped against a support to obtain a packed state where the volume is constant. The packed vol¬ ume is read on the graduated scale and the weight is measured. The tap density is then taken as the ratio between the measured weight and the packed volume. Fig. 1 shows experimental tab densities (D) versus volume chalk/cyclone sand ratios (%) obtained for mixtures of chalk (fine filler) having a mean particle size of 2 μm and cyclone sand (coarse filler) having a predominant particle size in the range from 150 to 250 μm. It is seen that the density of the mixture increases by addition of chalk. Generally, the fine/coarse filler ratio providing the highest density, and consequently the smallest pore volume is selected as the optimal fine/coarse filler ratio. How¬ ever, depending on the specific materials used, deviations may occur which makes it more preferably to use more or less fine or coarse filler material, respectively. The control of brittleness by varying the fine/coarse filler ratio is illustrated in the following examples. Shooting target in form of flying targets such as clay pigeons shall meet the specifications according to the International Shooting Union, 8000 Munich, Germany: size: a diameter of 110 mm, and a height from 25 mm to 26 mm; weight: from 100 to 110 g; color: red, yellow, black, or black-white; flight: stable, minimum 90 m; and others: shall break or give a clear visual sign if hit. 5. EXAMPLES In the examples, the following materials were used: Fine filler: "Powder Chalk" (chalk), calciumcarbonate having a particle size distribution with 10% (cumulative mass percent) of the particles having a particle size less than 0.5 um, 50% having a particle size less than 1.7 μm, and 90% having a particle size less than 6.0 μm; and the density of 2.7 g/cm a ; supplied by Grena Kalkbrud, Grena, Denmark; the particle size distribution was measured by sedimen- tation using a Sedigraph 5000 ET, from Micrometric, IMI. Coarse filler: "Cyclone Sand" (sand) (quarts powder ob¬ tained by cyclone- filtration of sand) having a particle size distribution with 65-70% of the particles in the range from about 150 μm to about and 250 μm; and a density of 2.3 g/cm 3 ; supplied by Dansk Kvarts Industri A/S, Skanderborg, Denmark; the particle size distribution was characterized by sieving using the following sieves: Binder: "Sulphur Powder" (sulfur) (325 mesh extra refined); supplied by Superfos Kemikalier A/S, Vedbaek, Denmark; Additives: "Ketjen Black" (carbon black); and Ammonium hydrogen phosphate; supplied by Struers Chem A/S, Roedovre, Denmark. Example 1 Sulfur-Chalk Based Clay Pigeons , 45S-55C (Comparison) A 12 kg moulding composition comprising 45% sulfur and 55% chalk by weight was heated to about 120 °C, mixed to form a homogeneous melt, and transferred to a compression mould shaped for the production of clay pigeons according to the specifications of the International Shooting Union. The chalk made the melted composition dry, but lubric¬ ating. The melted composition was compressed by applying a pres- 2 sure of 1 kg/cm and cooled within a period of about 5 seconds . Clay pigeons having a weight from 100 to 110 g, a diameter of 110 mm, a height from 25 to 26 mm, and a yellow color were produced. The clay pigeons were found to have an apparently good quality, however, of a low strength and extremely brittle. An unacceptable large number was unable to resist the material stress during handling. Example 2 Sulfur-Sand Based Clay Pigeons , 60S-40Q (Comparison) Clay pigeons were prepared as in example 1 with the use of 40% cyclone sand by weight instead of chalk. The quarts powder made the melted composition less dry than chalk. However, shooting field tests showed that the pigeon could not in all events produce a reliable indication of a hit, e.g. in form of dust or a fragment, although there was clear evidence that the material had been hit; several shots were just leaving holes in the pigeon. Example 3 Sulfur-Cuarts-ChalJ Based Clay Pigeons , 44S-5C-51Q Clay pigeons were prepared as in example 1 with the use of 44% sulfur, 5% chalk, and 51% cyclone sand by weight. The fine/coarse filler ratio was about 7.,7% by volume. The chalk prevented sedimentation of solid particles in the melted composition. The clay pigeons contained unde- sired voids, the strength was too high, and the brittle¬ ness was low. Shooting field tests showed that pigeons could be hit without indicating a hit. Example 4 SuIfur-øuarts-Chalk Based Clay Pigeons , 41S-29C-30Q Clay pigeons were prepared as in example 1 with the use of 41% sulfur, 29% chalk, and 30% cyclone sand by weight. The fine/coarse filler ratio was about 45% by volume. The same properties as in example 3 were obtained but with a lower strength. Shooting tests of 50 clay pigeons showed satisfactory shattering of the pigeon after a hit. Example 5 Sulfur-øuarts-Sand-Chalk Based Clay Pigeons , 29S-20C-51QS Clay pigeons were prepared as in example 1 with the use of 29% sulfur, 20% chalk, 40% cyclone sand and additional 11% sand by weight having a particle distribution in the range from 300 urn to 600 μm, and heating to 155 °C. The fine/coarse filler ratio was about 25% by volume. The material was homogeneous. The clay pigeons had the desired properties, and showed satisfactory shattering after a hit. Example 6 Sulfur-øuarts-Sand-Chalk Based Clay Pigeons , 29S-20C-51QS, Containing Carbon Black Clay pigeons were prepared as in example 5 with the use of 29% sulfur, 20% chalk, 39% cyclone sand, 11% sand (particle size 0.3-0.6 mm) and additionally 1% carbon black by weight. The fine/coarse filler ratio was about 26% by volume. The clay pigeons had all the desired properties as in example 5. In addition, all pigeons were black in color. Example 7 Sulfur-Quarts-Sand-Chalk Based Clay Pigeons, 29S-20C-51QS, Containing Fire Inhibitor Clay pigeons were prepared as in example 5 with the use of 29% sulfur, 20% chalk, 37% cyclone sand, 11% sand and additional 3% ammonium hydrogen phosphate by weight. The fine/coarse filler ratio was about 26% by volume. The clay pigeons had all the desired properties as in example 5. In addition, all pigeons tested extinguished themselves when put on fire. Example 8 Sulfur-Ouarts-Sand-Chalk Based Clay Pigeons , 6S-20C-74QS, Produced Ultrasonic Moulding Clay pigeons were prepared as in example 5 with the excep- tion that 6% sulfur, 20% chalk, 63% cyclone sand, and 11% sand (particle size 0.3-0.6 mm) were mixed and pressed in 2 a mould at 1 kg/cm simultaneously applying ultrasonic energy of 40 kHz by means of an ultrasonic moulding apparatus, BRANSON 150 W. The fine/coarse filler ratio was about 18% by volume. 2 The pressure was raised up to 2 kg/cm for a period of 2 seconds. The clay pigeons had all the desired properties as men- tioned in example 5. Compared to conventional mixing and heating, ultrasonic mixing and heating provide clay pigeons with much less sulfur. Example 9 Sulfur-øuarts-Sand-Chalk Based Clay Pigeons , 29S-20C-51QS Clay pigeons were prepared as in example 5 with the excep¬ tion that liquid sulfur was pressed into a mixture of quarts, sand and chalk powder pre-heated to 120 °C and evacuated for air. The sulfur containing material was allowed to cool to 105 °C whereafter it could be removed from the mould. The clay pigeons had all the desired properties as men¬ tioned in example 5. Example 10 Comparison with Conventional Clay Pigeons Clay pigeons were prepared as in example 5 with the composition as shown below in Table 1. The sand had a particle size from 100 to 300 μm, with 88% having a particle size of 180 urn. Chalk was of size 12 μ (>91%). The pigeons were tested for brittleness by being dropped on a concrete floor from a height of 50 cm. The average number of shattered pieces were compared with that of a resin-chalk based clay pigeon (pigeon 6) and a tar-pitch- chalk based pigeon (pigeon 7) supplied from Quick Lerduer, Kolding, Denmark. It is seen that the pigeons nos. 4 and 5 compare well with the conventional pigeons. Table 1 Cyclone Filler Pigeon Sulfur Chalk Sand Sand Weight Ratio 1 Pieces : No. (%) (%) (%) (%) (g) (%) (1) Fine/coarse filler volume ratio (2) Average number per pigeon for an average number of pigeons of 10 per each pigeon number i.d. Indefinite SUBSTITUTE SHEET ISA/EP

Claims: P a t e n t C l a i m s 1. A shattering article comprising filler material, consolidating binder, and optionally additives, CHARACTERIZED in that the filler material is a powder mixture of at least two components comprising i) fine particles a substantial part of which having a particle size from 1 μm to 50 μm, and ii) coarse particles a substantial part of which having a particle size from 50 μm to 1500 μm, having a fine/coarse filler ratio from 5% to 60% by volume. 2. A shattering article according to claim 1, CHARACTERIZED in that the fine/coarse filler ratio is in the range from 10% to 30% by volume, preferably about 25% by volume. 3. A shattering article according to any one of claims 1- 2, CHARACTERIZED in that at least 95% of the fine particles have a particle size from 10 urn to 20 urn, and that at least 95% of the coarse particles have a particle size from 100 um to 300 μm, preferably an average particle size of about 200 μm. 4. A shattering article according to any one of claims 1- 3, CHARACTERIZED in that the fine filler material is chalk or talc. 5. A shattering article according to any one of claims 1- 4, CHARACTERIZED in that the coarse filler material is sand, ash, or gravel. 6. A shattering article according to any one of claims 1- 5, CHARACTERIZED in that the fine and coarse filler materials and the optionally additives constitute from 20% to 95% by weight of the composition. 7. A shattering article according to any one of claims 1- 6, CHARACTERIZED in that the binder is sulfur, pitch, petroleum resin, phenolic resin, paraffin wax, or sucrose, preferably sulfur. 8. A shattering article according to any one of claims 1- 7, CHARACTERIZED in that the binder constitutes from 5% to 80% by weight of the composition, preferably from 20% to 45%, most preferred from 29% to 33%. 9. A shattering article according to any one of claims 1- 8, CHARACTERIZED in that an optional additive consists of a color pigment, preferably a high surface area carbon black powder, in a concentration in an amount from 0.5 to 2%, particularly about 1% by weight. 10. A shattering article according to any one of claims 1-9, CHARACTERIZED in that an optional additive consists of a fire inhibitor, preferably ammonium hydrogen phos- phate, in a concentration from 2% to 5%, particularly about 3% by weight. 11. A shattering article according to any one of claims 1-10 in form of a shooting target such as a clay pigeon. 12. A moulding composition for the production of a shattering article comprising a mixture of filler materials, consolidating binder, and optionally additives, CHARACTERIZED in that the filler material is a powder mixture consisting of i) fine particles a substantial part of which having a particle size from 1 μm to 50 μm, and ii) coarse particles a substantial part of which having a particle size from 50 μm to 1500 μm, having a fine/coarse filler ratio in the range from 5% to 60% by volume. 13. A moulding composition according to claim 12, CHARACTERIZED in that the fine/coarse filler ratio is from 10% to 30% by volume, preferably about 18% by volume. 14. A moulding composition, according to any one of claims 12-13, CHARACTERIZED in that at least 95% of the fine particles have a particle size from 1 um to 50 μm, prefer¬ ably from 10 um to 20 um, and that at least 95% of the coarse particles have a particle size from 100 um to 300 um, preferably an average particle size of about 200 μm. 15. A moulding composition according to any one of claims 12-14, CHARACTERIZED in that the fine filler material is chalk or talc. 16. A moulding composition according to any one of claims 12-15, CHARACTERIZED in that the coarse filler material is sand, ash, or gravel. 17. A moulding composition according to any one of claims 12-16, CHARACTERIZED in that the fine and coarse filler materials and the optionally additives constitute from 20% to 95% by weight of the composition. 18. A moulding composition according to any one of claims 12-17, CHARACTERIZED in that the binder is sulfur, pitch, petroleum resin, phenolic resin, paraffin wax, or sucrose, preferably sulfur. 19. A moulding composition according to any one of claims 12-18, CHARACTERIZED in that the binder constitutes from 5% to 80% by weight of the composition. 20. A moulding composition according to any one of claims 12-19, CHARACTERIZED in that an optional additive con¬ sists of a color pigment, preferably a high surface area carbon black powder, in a concentration in the range from 0.5 to 2%, particularly about 1% by weight. 21. A moulding composition according to any one of claims 12-20, CHARACTERIZED in that an optional additive con- sists of a fire inhibitor, preferably ammonium hydrogen phosphate, in a concentration in the range from 2% to 5%, particularly about 3% by weight. 22. A method of producing a shattering article, particu- larly a shooting target such as a clay pigeon comprising the steps of providing a moulding composition containing a binder; melting the binder; shaping the melt in a mould under pressure, an extruder, or a transfer press; and allowing the melt to cool; CHARACTERIZED in that the moulding composition is a moulding composition according to any one of claims 12-21. 23. A method of producing a shattering article, particu¬ larly a shooting target such as a clay pigeon comprising the steps of providing an homogeneous, dry, moulding com¬ position containing a binder; melting and shaping the com¬ position in a mould under pressure and simultaneous appli¬ cation of ultrasonic energy; and allowing the melt to cool; CHARACTERIZED in that the moulding composition is a moulding composition according to any one of claims 12-21.

Inventors: MALLING JESPER, MALLING, JESPER
Applicants: INNOVISION AS, MALLING JESPER, INNOVISION A/S
Application year: 1992
Main classification: F41J9
IPC codes: F41J1