FI74699C - MARKERINGSMEDEL SOM ANVAENDS I SPRAENGAEMNEN, FOERFARANDE FOER DERAS FRAMSTAELLNING OCH DERAS ANVAENDNING VID MARKERING AV SPRAENGAEMNEN. - Google Patents

Abstract

1. A tracer (marking agent) containing a) at least 1 per cent by weight of iron powder and/or powder of a ferromagnetic alloy and at least two of the following groups of substances : b) fluorescent pigments ; c) organic solvent-soluble, water-insoluble fluorescent materials ; d) colorant pigments ; e) sparingly soluble and heat-stable oxides and/or salts of rarer metals ; f) oxides and/or sparingly soluble salts of rare-earth metals ; in microanalytically well detectable amounts in the form of a homogeneous mixture with a thermoplastic material, characterized in that the thermoplastically processable material is a high molecular weight synthetic materials having a low water absorption capacity, a high specific heat capacity, a low thermal conductivity, and a low specific gravity, more specifically a synthetic material selected from the group consisting of polyethylenes, polypropylenes, polyamides, polycarbonates, polyesters, polyoxymethylenes and acrylonitrile-butadiene-styrene copolymers.

Description

The present invention relates to tracers for explosives which make it possible to identify the substance used by microanalytical methods in terms of origin and composition and, possibly, also the date of manufacture. The invention further relates to a process for the preparation of such markers and their use in the marking of explosives. The increasing theft and unauthorized use of explosives has led to the need to be able to clearly demonstrate the quality of the explosives and possibly also the time of manufacture. This need has led to legal provisions, including 15 Decree of the Swiss Federal Council on Explosive Substances of 26 March 1980, Art. 5, sentence 3, which reads: "An explosive must contain a tracer which allows its origin to be ascertained even after the explosion. The tracer requires the permission of the central warehouse, 20 which must take account of changed circumstances." To date, only one such marker has entered the market. It is a business name for a 3M product consisting of a laminate of 9 layers of melamine resin. Various substances are included in the layer 9 of the melamine resin, such as, for example, a fluorescent pigment, dyes and a magnetic substance. Presumably, in this case, films or sheets are first made, which are then crushed and ground. A product of this type is described, for example, in U.S. Patent 4,053,433.

It is known from U.S. Pat. No. 3,770,200 and the corresponding German Pat. No. 2,343,774 to mix four different, mostly rare elements in the form of their oxide, to melt them in a muffle furnace into a glass mass and then to make microglass beads from this melt by a conventional method. Although these products are resistant to explosive explosion, 2 74699 they are only very difficult to recover and separate from explosive waste. U.S. Patent No. 3,897,284 discloses this product for improvement by using non-stick organic materials having a melting point above 60 ° C instead of glass. According to the publication, the improvement is in particular in that the products thus obtained are more compatible with the explosive and do not tend to increase the sensitivity of the explosives as with glass beads. In the examples, only extremely low molecular weight polyethylenes, paraffin waxes or epoxy resins were used as non-stick organic substances, since only these make it possible to obtain a powder which must be prepared from the mixture after mixing with the metal oxide. This is done in all pre-15 characters by spray drying. However, spray drying is only possible in the case of organic substances which have a very low viscosity at the given temperatures. The products thus obtained, in turn, were apparently unsuitable in practice and did not lead to trade-20 products.

U.S. Pat. No. 4,131,064 and U.S. Pat. No. 4,197,104 disclose other tracers which are prepared with particles of potassium silicate binder and optionally further coated with a thin layer of polyethylene. In addition, by adding different ferrites, an attempt was made to obtain products with different Curie points. These products have also apparently had a negative impact on the stability and shelf life of explosives. Furthermore, the coding appears to have changed more or less strongly in the event of an explosion due to a different temperature effect, so that a clear interpretation of the code is no longer possible. It is known from U.S. Patents 3,961,106, 3,967,990 and 3,998,838 to coat the markers previously described above with a thin layer of low molecular weight polyethylene or wax to improve compatibility with the explosive.

3,74699

However, even such products have so far clearly not been able to meet all practical requirements. A tracer that satisfies all the requirements must meet the following conditions: 5 a) The tracer must remain unchanged in the explosive for many years. It must not render the explosive unstable or alter its composition.

b) The tracer must be able to withstand an explosion and remain at the explosion site.

10 c) The tracer must be detectable in other explosive wastes, distinguishable from these and clearly analyzable.

d) The tracer must be able to withstand a system that varies greatly and then contains compounds that are not present in the environment, at least in the same combination.

e) The tracer must be well and clearly analyzable on a micro scale.

f) The tracer must be resistant to water and conventional solvents.

The 3M product described above partially meets these conditions, but due to its complex manufacturing process, it significantly increases the cost of the explosive. The object of the invention was to provide a tracer which meets all the above-mentioned requirements for tracers for explosives.

It has surprisingly been found that high molecular weight polyethylene and polypropylene with low water absorption, high specific heat, low thermal conductivity and low specific gravity are suitable for thermoplastic processing so as to bind a) at least 1% by weight or iron powder homogeneously mixed ferromagnetic metal alloy powder and at least two of the following two groups of substances: 4 74699 b) fluorescent pigments, c) organic solvent soluble, water-insoluble fluorescent substances, d) color pigments, 5 e) rare and water-resistant and heat-resistant oxides of rare metals oxides and / or sparingly soluble salts of earth metals in detectable amounts, and form a tracer with excellent properties. It is clear that such plastics containing the above-mentioned substances can no longer be converted to a powder by spray-drying; however, after cooling the melt, they can be granulated and ground. After grinding, the particle size is preferably 100-1200 yarn. The products thus obtained meet all the above requirements for a good tracer.

It is essential for the invention that the plastics used are high molecular weight as well as thermoplastic, and at the same time have a low water absorption capacity, a high specific heat, a low thermal conductivity and a low specific gravity.

Iron powder and / or ferromagnetic alloy powder must be at least 1% in order for the tracer to be exposed to explosive waste by means of magnets. The markers according to the Kek-25 invention use 3 to 20% by weight of ferromagnetic material. Amounts of 5-12% by weight have proven to be particularly advantageous.

For clear coding and interpretation of the coding of the tracer according to the invention, there must be at least two of the groups of substances: fluorescent pigments, fluorescent substances, color pigments, rare metal oxides and / or salts and rare earth oxides and / or sparingly soluble salts. The more different groups of substances are used, the greater the variability and the easier it is to find out the manufacturer of the explosive, the date of manufacture and the composition. In order for the groups of substances in the tracers according to the invention to also be well determined microanalytically, they must be present in the following amounts: b) fluorescent pigments 0.1 to 8% by weight, preferably 2 to 5% by weight; C) fluorescent substances 0.1-5% by weight, preferably 1-3% by weight; d) color pigments 0.5 to 8% by weight, preferably 1 to 5% by weight; e) oxides and / or salts of rare metals 0.5 to 8% by weight, preferably 1 to 5% by weight; f) oxides and / or salts of rare earth metals from 0.5 to 5% by weight, preferably from 1 to 3% by weight.

According to the invention, these tracers are prepared by mixing the various ingredients into a homogeneous mixture in a melt of thermoplastic polymer, cooling the melt, granulating and grinding to a grain size of 100-1200 μm.

Fluorescent pigments should be insoluble in water and organic solvents, while fluoro-20 sensitizers should be insoluble in water but soluble in organic solvents. Based on this, these groups of substances can be easily distinguished from each other and determined analytically independently of each other. Color pigments, rare metal oxides and / or salts and rare earth oxides and / or sparingly soluble salts must also be insoluble in water and organic solvents, so that they remain in the residue and can be reliably analyzed side by side.

In order to homogeneously divide the different groups of substances into the tracer, they must be added to the melt of polymers and mixed vigorously. Mixing devices with a particularly good shear and mixing effect have proven to be suitable for this mixing. The single-screw press-35 met is not yet suitable for this purpose. Twin-screw presses are well suited for generating 6,74699 high shear forces. For example, a two-screw mixer of the trade name Werner & Pfleiderer, Stuttgart, which is a model ZSK, has proved to be suitable. A batch-type Banbury-type forced agitator also seems suitable for a 5-van. The homogeneous mixtures are then granulated. The edge length of the granules should be 2-6 mm. Such granulated products can be easily ground into a powder having a grain size of 100-1200 μm. It is desirable to have a relatively small grain size distribution because parts of the same size behave more uniformly under explosive conditions than products with a very wide grain size distribution. If the lengths of the edges of the granules are greater than 6 mm, a tracer with a relatively wide grain size distribution is obtained during grinding, which is not desirable in the case of the marking of explosives. In explosives, optimal results have been achieved with tracers with as uniform a grain size as possible in the range of 200-600pn. If desired, particles with particularly large or particularly small edge lengths can be separated from the ground product by screening, thus achieving a narrower grain size distribution. Otherwise, the optimal grain size distribution may also depend to some extent on the quality of the explosive to be marked, as the markers should also be mixed as homogeneously as possible with the explosive in question.

Polyethylene and polypropylene in particular have proven to be suitable as plastics of high molecular weight thermoplastic polymers with low water adsorption capacity, high specific heat, low thermal conductivity and low specific gravity. These polymers can be mixed homogeneously melted homogeneously with analytically detectable groups of substances. They are also suitable for keeping these substances unchanged for a long time and for enabling their analytical determination for the interpretation of the code 35. Because the polymers used have reproducible thermal properties that can be microanalytically determined by differential thermal analysis, these criteria can also be used for identification and interpretation of coding. The molecular weight or melt viscosity of the polymers are uncritical as long as the polymers are thermoplastically processable, but still withstand water and organic solvents sufficiently well at room temperature. High specific heat and low thermal conductivity protect materials imported into plastic from the effects of explosive heat. The low specific gravity allows the markers according to the invention to be more easily separated from the explosive waste by means of liquids with a suitable specific gravity.

As stated above, the ferromagnetic parts are only intended for the separation and enrichment of the tracers according to the invention from explosive wastes and not for the analytical interpretation of the coding. Iron powders with a maximum grain size of less than 60 microns have proven to be particularly suitable as ferromagnetic substances. Such iron powders with a purity of 99.5% are available, for example, under the name RZ60 from Mannesmann-DEMAG. In principle, all other ferromagnetic alloys are also possible, provided that they are available in powder form. If these alloys contain relatively rare alloying metals, they can in principle also be used for identification and interpretation of coding.

- · The substances added to the tracers according to the invention should be able to withstand a short-term thermal effect of 200-300 ° C. Suitable fluorescent pigments are, in principle, pigments which can be clearly distinguished on the basis of their fluorescence-30 inner spectrum and their own color. Examples of suitable fluorescent pigments are the orange, green and yellow pigments sold under the trade name Industrial Colors Ltd. in England under the name FLARE 910, or the pigments LUMILUX C-luminescent under the trade name Riedel-de Haen AG, 35 West Germany. Suitable fluorescent substances are, in principle, all fluorescent substances which are soluble in organic solvents and which can be dissolved from the tracer by means of an organic solvent. Fluorescent substances should be insoluble in water, so that they cannot dissolve in the tracer under the influence of water. Examples of suitable fluorescent substances are the products sold under the trade name Ciban under the name UVITEX OB, UVITEX 127 and UVITEX OB-P, and under the trade name ICI under the name Fluolite XNR and FLUOLITE XMP. On the other hand, all sufficiently insoluble and heat-10-resistant pigments with a clearly identifiable emission spectrum can be used as color pigments. Suitable color pigments are, for example, Sicoplast yellow 12-0190 and Sicoplast red 32-0030, as well as, for example, pigments sold under the trade name ICI under the name Waxoline in the colors blue, ruby red, 15 green and yellow.

Suitable sparingly soluble and heat-resistant rare metal oxides and / or melts are, for example, titanium dioxide, copper oxide, zinc oxide, strontium carbonate, cadmium sulphide, antimony trioxide, barium sulphate, lanthanum trioxide and bismuth trioxide.

Suitable rare earth metal oxides and / or sparingly soluble salts are, in particular, cerium (IV) oxide and other oxides of lanthanides, and possibly oxalates. Alternatively, sparingly soluble and heat-resistant oxides and / or salts of all metals may be used alone or in combination as long as they can be clearly identified microanalytically, e.g. by X-ray fluorescence spectrometry.

The tracers according to the invention are in principle suitable for labeling substances in terms of their origin, composition and date of manufacture, in so far as there is serious interest in this. Such interest exists or arises mainly in the case of substances that may endanger the safety of the general public. Thus, the tracers according to the invention can be used in particular for the identification of powdered substances, the identification of which in terms of substance type, manufacturer and date of manufacture is important or reasonable for safety or criminological reasons. This issue is of particular importance for explosives. The marking agents according to the invention are therefore proposed for use in particular for the marking of explosives.

The following examples describe some typical embodiments of the tracers of the invention, as well as their preparation. All 10 percentages presented herein are by weight.

Example 1 15.2 kg of low pressure polyethylene powder (76%) 2.0 kg of iron powder (10%) 1.6 kg of fluorescent pigment (8%) 15 0.6 kg of cerium (IV) oxide (3%) 0.6 kg of antimony trioxide (3 %) is mixed as a dry powder in a high-speed centrifugal mixer model Henschel FM 75 with a volume of 75 l, using a mixer at a speed of 1600 rpm for 2 minutes. This mixture is poured

Werner & Pfleiderer ZSK 53 M in a 50-screw twin-screw mixer feed tank and homogenized to a coil rotation speed of 200 rpm and a pulp temperature of 170 ° C. The homogenized mixture is taken out and granulated into cylindrical granules with a side length of "· * · 4 mm, in a Pallmann PP8 type grit at a carrier gas temperature of not more than 4 ° C, up to an upper grain size limit of 630. The finished tracer has a grain size distribution of 80-630. with a weighted average of 310 μm The following commercial materials were used as raw materials: Low pressure polyethylene powder ELTEX A 4090 P with a grain size distribution of 30-900 μm, melt index (2.16 Kp / 190 ° C) 9 g / 10 min and density (23 ° C) 3 0.953 g / cm ELTEX is a trademark of 35 Solvay, Belgium.

10 74699

Iron powder RZ 60 with an upper grain size limit of 60 μm and a purity of 99.5%. RZ is a trademark of Mannesmann-DEMAG, West Germany.

5 Fluorescence pigment FLARE 910 orange 4, orange natural color. FLARE is a trademark of INDUSTRIAL COLORS LTD, England.

Cerium (IV) oxide 10 Product of the trade name MERK, West Germany, with a purity of 99.9%.

Antimony trioxide TIMONOX-WHITE STAR, purity 99%. TIMONOX-WHITE STAR is a quality mark of the business name ASSOCIATED LEAD Manufactures Ltd., 15 England.

Example 2

The following dry, powdered components are mixed in a Lödige FM 130D plow mixer with a volume of 130 l and using a mixer rpm of 20 rpm for four minutes and then placed in a Battenfield-EKK PWE EV-type rotary roller press feed tank, homogenized 30 rpm and a pulp temperature of 145 ° C, taken out and granulated: 25 31.6 kg high pressure polyethylene powder (79%) 4.0 kg iron powder (10%) 2.4 kg fluorescent pigment (6%) 1.2 kg lanthanum (III) oxide (3%) 0.8 kg of titanium dioxide (2%) 30 The cylindrical granules thus obtained with a side length of 3 mm are ground according to Example 1 to a final fineness of 80-630 .mu.m.

The following types of raw materials available on the market were used: 35 High pressure polyethylene powder

Coathylene HO 2454, based on Lotrene MD 0707, π 74699 grain size distribution 80-630 μm, melt index (2.16 Kp / 190 ° C) 7 g / 10 min and density (23 ° C) 0.924 g / cm 3. Coathylene is a quality mark of the company name Plast-Labor SA, Switzerland, Lotrene is a quality mark of the company name CdF, France.

5 Iron powder

According to Example 1.

Fluorescence fragment FLARE 910 yellow 27, yellow natural color, vendor as in Example 1.

10 Lanthanum (III) oxide

Business name Merk, West Germany, product, purity 99.9%. titanium oxide

Kronos CL 220, purity 92.5%. Kronos is a quality mark of the business name Kronos-Titan GmbH, West Germany.

15 Example 3

According to the method of Example 1 (mass temperature, however, 195 ° C), the following dry, powdery components are prepared into cylindrical granules with a side length of 5 mm and ground according to the method of Example 1 to a final fineness of 80-630 μm: 15.4 kg of polypropylene powder (77 2.0 kg of iron powder (10. 1.4 kg fluorescent pigment (7%) 0.6 kg yttrium (III) oxide (3%) 25 0.6 kg zinc oxide (3%) The following types of raw material available on the market were used:

polypropylene powder

Moplen FL V 20 with a grain size distribution of 40-450 μm, 30 melt index (2.16 Kp / 230 ° C) 16 g / 10 min and density (23 ° C) 3 0.90 g / cm. Moplen is a quality mark from Montedison, Italy. Iron powder

According to Example 1.

Fluorescence Detector 35 Flare 910 green 8, green own color, seller as in example 1.

12 74 69 9

Yttrium (III) oxide

Business name Merkin, West Germany, product with a purity of 99.9%.

Zinc oxide 5 Product of the trade name Lehmann & Voss, West Germany, with a purity of 99.5%.

Example 4

In analogy to the procedure described in Example 1, the following components were mixed, homogenized, granulated and ground: 16.6 kg of high pressure polyethylene powder (83%) 2.0 kg of iron powder (10%) 0.2 kg of fluorescent substance (1%) 0.6 kg of color pigment ( 3%) 15 0.6 kg strontium stearate (3%) The following types of raw materials available on the market were used:

High pressure polyethylene powder As in Example 1.

20 Iron powder

As in Example 1.

Fluoresenssiaine

Uvitex OB, no intrinsic color, but blue fluorescence at 435 nm (max. ^). Uvitex is a quality mark of the business name Ciba-Ceigy AG, 25 Switzerland.

the color pigment

Sicoplast-Gelb 12-0190, which has a yellow intrinsic color and consists of cadmium-zinc sulphide. Sicoplast is a quality mark of the business name BASF, West Germany.

30 Strontium stearate

Product of the trade name Bärlocher, West Germany, with a purity of 98%.

Example 5

The tracers of Examples 1-4 above were mixed in amounts of 0.05-1% by weight of the explosives 74,699. The tracer residues from the test blasts were enriched with magnets. The mixture of tracers and other ferromagnetic residual components was separated by aqueous solutions of different densities. The fraction containing 5 tracers alone was analyzed for its constituents. It was, of course, possible to distinguish between the different tracers and thus to identify the explosive used.

Claims (2)

14 74 6 9 9 1. Tracer for use in explosives containing 5 a) at least 1% by weight of iron powder and / or powder of Ferro magnetic alloys and at least two of the following groups of substances: b) fluorescent pigments, c) soluble in organic solvents, insoluble in water fluorescent substances, d) color pigments, e) sparingly soluble and heat-resistant oxides and / or salts of rare metals, f) oxides and / or sparingly soluble rare earth metals in a thermoplastic material in micronanytically well-detectable amounts, known homogeneously mixed therewith, - the material to be processed is high molecular weight polyethylene or polypropylene having low water adsorption capacity, high specific heat, low thermal conductivity and low specific gravity, and that the tracer contains: a) iron powder and / or ferromagnetic alloy powder from 3 to 20% by weight and at least the following two degrees ä: 25 b) fluorescent pigments 0.1-8% by weight, c) fluorescent substances 0.1-5% by weight, d) color pigments 0.5-8% by weight, e) oxides and / or salts of rare metals 0, 5-8% by weight and 30 f) oxides and / or salts of rare earth metals 0.5% by weight, and the ingredients are mixed into a homogeneous mixture as a melt, which is then granulated and ground to a grain size of 100-1200. 2. A process for the preparation of a tracer for use in explosives containing 1β 74699 (a) at least 1% by weight of iron powder and / or ferromagnetic alloy powder and at least two of the following groups of substances: b) fluorescent pigments, 5 c) soluble in organic solvents, water-insoluble d) color pigments, e) sparingly soluble and heat-resistant oxides and / or salts of rare metals, 10 f) oxides of rare earth metals and / or sparingly soluble salts in thermoplastic material in microanalytically highly detectable amounts, homogeneously mixed, characterized in that the low water adsorption , a melting of high molecular weight polyethylene or polypropylene with a high specific heat, low thermal conductivity, 15 and low specific gravity is homogeneously mixed with a) iron powder or ferromagnetic alloy powder from 3 to 20% by weight of the total weight of the mixture and from at least 20 b) fluorescent pigments 0.1-8% by weight, c) fluorescent substances 0.1-5% by weight, d) color pigments 0.5-8% by weight, e) oxides and / or salts of rare metals 0.5-8% by weight and f) oxides and / or salts of rare earth metals 0.5-5% by weight of the total weight of the mixture, the melt is cooled, granulated and ground to a grain size of 100-1200. Use of a tracer 30 according to claim 1 for the labeling of explosives. 74699 BC 1. Markers for use in the manufacture and use of 5% of the following: (d) a color pigment; the thermoplastic material is made of polyethylene or polypropylene with a wattage button, a specific color, a color warping method and a ferrule with a special weight, and the following markings are used: a) from 3 to 20% by weight and at least one of the sub-groups in the group ande game: 25 b) fluorescent pigment 0.1-8 wt%, c) fluorescent pigment 0.1-5 wt%, d) fluorescent pigment 0.5-8 wt%, e) oxide och / eller salt with a content of 0 , 5-8 wt.%, 30 f) oxide and / or salt of a jordart metal of 0.5-5 wt.%, And ingredients of a mixture of homogeneous bleaching in the form of granules and malt to the batches of 100-1200 μm. 35 2. For the purposes of this Regulation, the following shall apply in particular and in particular: