Treated ammonium octamolybdate composition

The present invention relates generally to the production of ammonium octamolybdate compositions, and more particularly to the production of ammonium octamolibate powder compositions useful in the formulation of optically markingable inks and polymers.

Ammonium Octamolib Date: (NH₄)₄Mo₈O₂₆Alternatively, "AOM" is a commercially useful molybdenum composition, available in various phases or isomers. The compound called ammonium octamolybdate is also commonly used in various forms as "diammonium catenatetramolybdate", "ammonium tetramolybdate", "tetraammonium hexamolybdate" or by CAS number 12411-64-2. Is known for. The α phase or α-AOM is of particular interest here, but other phases are known and can be used in several applications.

α-AOM is usually ammonium dimolybdate: (NH₄)₂Mo₂O₇Or it is manufactured by thermal decomposition of "ADM". The pyrolysis process follows the following basic chemical reactions.

(1) 4 (NH₄)₂Mo₂O₇+ Heat α- (NH₄)₄Mo₈O₂₆+ 4NH₃+ 2H₂O Alternatively, α-AOM is also like that disclosed in US Pat. No. 4,762,700 entitled "Ammonium Octamolibdate-α", which is incorporated herein by reference in all that it discloses. It can also be produced by an aqueous or wet process.

Although α-AOM is commonly used as a smoke suppressant for various types of plastic materials, it can also be used in the formation of various types of optically markable ink compositions. Such ink compositions change color in response to light, usually laser irradiation, but other light sources can be used. The color change is the result of a change in the oxidation state and / or the formation of non-stoichiometric products of the AOM constituents of the ink composition.

Several AOM-based optically markable compositions or inks are entitled US Pat. Nos. 7,485,403 and 8,048,605 (both entitled "Laser Markable Compositions", both of which are referred to in reference to all of their disclosures. Included in the specification). Briefly, examples of ink compositions disclosed in the '403 and '605 patents include polyvalent metal oxyanions, solvents, and binders. The oxyanion of the multivalent metal can contain AOM, especially α-AOM, but other materials have also been identified. Solvents can include any wide range of solvents commonly used for inks and lacquers, such as water, ethanol, ethyl acetate, isopropyl alcohol, and hydrocarbons. The binder is usually a polymer and can contain acrylic resin, cellulose, polyvinyl alcohol, polyester and the like. The binder can further contain unstable groups such as hydroxyl, acetoxy, ether acetal, or halogen. The disclosed ink compositions can also include a number of additional additives and compositions due to a wide range of factors and desired ink properties, also as described in the patent above.

Generally speaking, various inks or optically markingable compositions are formed by mixing appropriate amounts of AOM, solvent, and binder material to form a lacquer. The marking material (eg paper or cardboard) is then lacquered and dried. The actual marking and image formation process is carried out by directing the ink to a suitable wavelength of light (eg, a laser beam), thereby changing the color of the ink and thereby forming the desired image. Can be done.

In addition to the ink, in the referenced patents, AOM can also be introduced directly into various types of polymers such as nylon, polyester, polyamide, polycarbonate, polyacrylate, polymethacrylate, ABS polymer, polyolefin and the like. It is also taught that this can be marked directly as desired in a process similar to that subsequently used for inks.

<p num="0009"><patcit num="1"><text>U.S. Patent 4,762,700</text></patcit><patcit num="2"><text>U.S. Patent 7,485,403</text></patcit><patcit num="3"><text>U.S. Patent 8,048,605</text></patcit></p>

<p num="0010"> The treatment method provided an initial supply of ammonium octamolybdate precursor powder with a bimodal particle size distribution; an initial supply of ammonium octamolybdate precursor powder moistened with a constant amount of solvent. Forming body powder; and adsorbing the applied solvent to the moist intermediate powder over a period of time; steps can be included, the amount and time of the applied solvent being substantially monomodal grains. It is sufficient to form a treated ammonium octamolybdate powder composition with a diameter distribution.</p><p num="0011"> In addition, a certain amount of water is added to the initial supply of ammonium octamolybdate powder having a bimodal particle size distribution, and the added water is added to the initial supply of ammonium octamolybdate powder over a certain period of time. The amount and time of water added produced by adsorption is sufficient to produce a treated ammonium octamolybdate powder composition with a monomodal particle size distribution, ammonium octamolybdate composition. Things are also disclosed.</p><p num="0012"> It also contains polyvalent metal oxyanions, solvents, and binders, and improvements include applying a certain amount of solvent to the initial feed of ammonium octamolybdate precursor powder to form a moist intermediate powder. The use of ammonium octamolybdate powder, which is produced by adsorbing the applied solvent on a moist intermediate powder over a certain period of time and has a substantially monomodal particle size distribution, as an oxyanion of a polyvalent metal. Improved optical marking of the type in which the amount and time of solvent to be included and applied is sufficient to form a treated ammonium octamolybdate powder composition with a substantially monomodal particle size distribution. Ink compositions are also disclosed.</p><p num="0013"> In another embodiment, the treatment method provides an initial supply of ammonium octamolybdate precursor powder with a bimodal particle size distribution; an intermediate adsorbent; the intermediate adsorbent is subjected to a constant amount of solvent. And generate an intermediate adsorbent containing the solvent; place the initial supply of the intermediate adsorbent containing the solvent and the ammonium octamolybdate precursor powder in the container; seal the container; and the ammonium octamolybdate precursor. The initial feed of the powder can include adsorbing the solvent desorbed from the intermediate adsorbent over a period of time; the amount and time of the solvent is a treatment with a substantially unimodal particle size distribution. It is sufficient to form the prepared ammonium octamolybdate powder composition.</p><p num="0014"> Yet another aspect of the treatment method is an initial feed of ammonium octamolybdate precursor powder having a bimodal particle size distribution and a retained moisture content of at least about 0.1% by weight as measured by dry weight loss. Feed; place an initial supply of ammonium octamolybdate precursor powder in a container; seal the container; and place the sealed container at a temperature of at least about 30 ° C, substantially monomodal particles. Heat for sufficient time to form a treated ammonium octamolybdate powder composition with a diameter distribution; Can be included.</p><p num="0015"> A currently preferred representative embodiment of an example of the present invention is shown in the drawings.</p>

<figref num="1">FIG. 1 illustrates the basic process steps in one aspect of the method of producing a treated ammonium octamolibdate composition.</figref><figref num="2">FIG. 2 is a particle size histogram and a plot of the integrated sieve distribution of standard commercially available standard ammonium octamolybdate precursor materials with a bimodal particle size distribution.</figref><figref num="3">FIG. 3 is a particle size histogram and a plot of the integrated sieving distribution of a treated ammonium octamolybdate powder composition with a monomodal particle size distribution.</figref><figref num="4">FIG. 4 is a scanning electron micrograph of a conventional ammonium octamolibdate precursor material at 2000x magnification.</figref><figref num="5">FIG. 5 is a scanning electron micrograph of the treated ammonium octamolibdate powder composition at 2000x magnification.</figref><figref num="6">FIG. 6 is a particle size histogram and a plot of the integrated sieving distribution of the superground ammonium octamolybdate precursor material.</figref><figref num="7">FIG. 7 is a particle size histogram and a plot of the integrated sieve distribution of the partially treated ammonium octamolybdate powder composition of Experiment 1 of the bed steam treatment process.</figref><figref num="8">FIG. 8 is a particle size histogram and a plot of the integrated sieving distribution of the partially treated ammonium octamolybdate powder composition of Experiment 2 of the bed steam treatment process.</figref><figref num="9">FIG. 9 is a histogram of the particle size and the integrated sieving distribution of the treated ammonium octamolybdate powder composition of Experiment 3 of the bed steam treatment process.</figref><figref num="10a">FIG. 10a is a histogram of the particle size of the second sample portion of the treated ammonium octamolibdate powder composition of Experiment 4 of the bed steam treatment process and a plot of the corresponding integrated under-sieving distribution.</figref><figref num="10b">FIG. 10b is a histogram of the particle size of the third sample portion of the treated ammonium octamolybdate powder composition of Experiment 4 of the bed steam treatment process and a plot of the corresponding integrated under-sieving distribution.</figref><figref num="11a">FIG. 11a is a plot of the particle size histogram and the corresponding integrated under-sieving distribution of the first sample portion of the treated ammonium octamolybdate powder composition of Experiment 5 of the bed steam treatment process.</figref><figref num="11b">FIG. 11b is a histogram of the particle size of the second sample portion of the treated ammonium octamolybdate powder composition of Experiment 5 of the bed steam treatment process and a plot of the corresponding integrated under-sieving distribution.</figref><figref num="11c">FIG. 11c is a histogram of the particle size of the third sample portion of the treated ammonium octamolybdate powder composition of Experiment 5 of the bed steam treatment process and a plot of the corresponding integrated under-sieving distribution.</figref><figref num="12">FIG. 12 is a histogram of the particle size of the ammonium octamolybdate precursor powder material used for the rotary dryer steam treatment process and a plot of the integrated sieving distribution.</figref><figref num="13">FIG. 13 is a particle size histogram and a plot of the integrated sieving distribution of the treated ammonium octamolybdate powder composition produced by the rotary dryer steam treatment process.</figref><figref num="14">FIG. 14 is a particle size histogram and a plot of the integrated sieving distribution of the pretreated ammonium octamolybdate precursor powder material used for the solvent spray process.</figref><figref num="15">FIG. 15 is a plot of the particle size histogram and the corresponding integrated under-sieving distribution of the composition produced in Experiment 1 of the solvent spray process.</figref><figref num="16">FIG. 16 is a plot of the particle size histogram and the corresponding integrated under-sieving distribution of the composition produced in Experiment 2 of the solvent spray process.</figref><figref num="17">FIG. 17 is a plot of the particle size histogram and the corresponding integrated under-sieving distribution of the composition produced in Experiment 3 of the solvent spray process.</figref><figref num="18">FIG. 18 is a plot of the particle size histogram and the corresponding integrated under-sieving distribution of the composition produced in Experiment 4 of the solvent spray process.</figref><figref num="19">FIG. 19 is a schematic representation of the basic process steps in another aspect of the method of producing a treated ammonium octamolibdate composition.</figref><figref num="20">FIG. 20 is a schematic representation of the basic process steps in yet another aspect of the method of producing a treated ammonium octamolibdate composition.</figref><figref num="21">FIG. 21 is a histogram of particle size and a plot of the integrated under-sieving distribution of the composition produced by the intermediate adsorbent process shown in FIG.</figref>

Various aspects of method 10 for producing the treated ammonium octamolybdate composition 12 are shown in FIG. 1, which comprises providing an initial supply of ammonium octamolybdate (AOM) precursor powder 14. Can be done. In a typical embodiment, the ammonium octamolybdate precursor powder 14 can contain an α-AOM powder produced by thermal decomposition of ADM. The α-AOM precursor powder 14 may have a substantially bimodal particle size distribution 16 with two mode peaks 18 and 20, as best seen in FIG. A water-like solvent 22 can then be applied to the initial feed of the ammonium octamolybdate precursor powder 14 to form a moist intermediate powder composition 24.

As described in great detail here, solvent 22, in the form of liquid or water vapor (ie gas), is added or applied to the initial feed of AOM precursor powder 14 in various ways to provide a moist intermediate. The powder composition 24 can be formed. For example, in one embodiment, the solvent 22 is added to the AOM precursor powder 14 in liquid form (eg, as the atomization stream 25 produced by one or more atomization nozzles 26), plus the solvent 22 throughout the AOM precursor powder 14. It can be evenly dispersed. In another embodiment, the solvent 22 can first be vaporized, i.e. converted to steam 28 by the steam generator 30 (in embodiments where the solvent 22 is water). Water vapor 28 can then be applied to the AOM precursor powder 14 (eg, through one or more water vapor ports 32) to form a moist intermediate powder composition 24.

In some embodiments, the initial feed of AOM precursor powder 14 is stirred in rotary or other form during the wetting process to allow solvent 22 (ie, in liquid form or vapor) to the AOM precursor powder 14. It may be desirable to promote a more uniform application. In one embodiment, the drum-type rotary stirrer 34 can be used to stir or rotary stir the AOM precursor powder 14 while applying solvent 22. Alternatively, other arrangements are possible as described in more detail herein.

As mentioned above, applying solvent 22 (ie, in liquid or vapor form) to the initial feed of AOM precursor powder 14 forms a moist intermediate powder composition 24. The wet intermediate powder composition 24 is then adsorbed with the applied solvent 22 for a time sufficient to produce the treated AOM composition 12. During the adsorption process, some physical properties of AOM precursor powder 14 change significantly. For example, during the solvent adsorption process, the particle size distribution of the AOM precursor powder 14 has a single mode peak 38 from a substantially bimodal distribution 16 (FIG. 2) with two mode peaks 18 and 20. It changes or shifts to a substantially monomodal distribution 36 with. See Figure 3.

In addition to changes or transitions in particle size distribution characteristics, the treatment process 10 of the present invention is believed to result in changes in the surface morphology or texture of the individual particles of the treated AOM composition 12. For example, with reference primarily to FIGS. 4 and 5, scanning electron micrographs of the untreated AOM precursor powder 14 (FIG. 4) and the treated AOM composition 12 (FIG. 5) show the surface texture of the individual particles. It suggests that some changes have occurred. At this time, changes in surface texture may have some impact on the improved performance of the treated AOM composition 12 of the present invention when used in the formation of optically markable inks and polymers. It is believed that.

Seen primarily back to FIG. 1, the moist intermediate product 24 can be further treated if desired before being recognized as the final treated AOM composition 12. For example, the moist intermediate product 24 can be further heated / dried in an oven or dryer 54 to further reduce the level of residual moisture that may be contained in the intermediate product 24. The intermediate product 24 can also be subjected to further grinding or grinding steps 56 to decompose larger aggregates that may have formed during the treatment process. The grinding or grinding step 56 can be performed on either the untreated intermediate product 24 or the dried intermediate product from the dryer 54.

The final processed AOM composition 12 can then be used in the production of AOM-based optically markingable inks and polymer compositions. The treated AOM composition 12 can be used to replace all or part of the conventional AOM required for a particular formulation to improve the performance of the ink and / or polymer composition.

A major advantage of the treatment method of the present invention is that it produces a treated AOM composition 12 that exhibits improved performance when used in the manufacture of AOM-based optically markingable inks and polymers. For example, the treated AOM composition 12 of the present invention provides improved viscosity performance of the ink lacquer composition produced from the treated AOM composition 12. More specifically, by using the treated AOM composition 12, an ink cracker or composition having a viscosity generally lower than that normally achievable with conventional AOM compositions is obtained. The lower viscosities of the ink compositions produced using the treated AOM composition 12 of the present invention are due to the lower viscosities of additional liquids or other viscosity modifiers during the ink mixing step (these are of dry inks). It is important in that it eliminates the need to add (which can adversely affect performance). In addition, the use of the treated AOM composition 12 also provides improved performance of the ink composition obtained after the optical marking process. Such improved performance includes, but is not limited to, perceived color (ie, whiteness) and optical density characteristics.

Moreover, the ability to easily and quickly transition or convert the particle size distribution from bimodal 16 to monomodal 36 using the treatment methods described herein is also a conventional means (eg milling and / or It is advantageous in that it is difficult to achieve the desired monomodal distribution (by the classification process). For example, as described above, the ammonium octamolybdate composition used in the optically markingable ink generally preferably contains an α form (ie, α-AOM) produced by thermal decomposition of ammonium dimolybdate (ADM). Pyrolysis α-AOM usually shows a bimodal particle size distribution 16 with two mode peaks 18 and 20, as best seen in FIG. Moreover, these mode peaks usually appear at particle sizes of approximately 1 μm and 10 μm. The particle size of 1 μm is very small, usually on the order of particles contained in cigarette smoke and cannot be easily removed or separated from larger dimensions. Although 10 μm particles can be easily reduced in size by various types of grinding or grinding processes, even the smaller dimensions of 10 μm particles have no practical benefit to such grinding or grinding processes for most applications. Become a thing. Further complicating the grinding or classification process is that the α-AOM powder is usually not fluid, which creates difficulty in handling the powder for such a process.

Also importantly, by preliminary testing, the monomodal particle size distribution 36 of the treated AOM composition 12 of the present invention (FIG. 3) is an improvement over the optically markingable ink composition 12 of the present invention. It is shown that it is not always the only factor that provides the desired performance. For example, conventional AOM materials that have been further treated and classified to obtain a substantially monomodal particle size distribution provide an optically markable ink with improved performance of the treated AOM composition 12 of the present invention. There wasn't. That is, between the treated AOM composition and the untreated AOM composition, a monomodal or nearly monomodal particle size distribution of the AOM composition 12 treated by further treating the latter was achieved. Even in some cases, there is still a big difference.

As previously briefly described, at this time, the improved performance (compared to untreated AOM) of the treated AOM composition 12 of the present invention is also a partially treated AOM composition. It is believed that it may also be due to morphological changes in the texture of the 12 individual particles. See Figures 4 and 5. The specific structural basis for the improved performance of the processed AOM12 is not fully understood at this time, but as confirmed herein, a number of process steps have achieved these advantages. Is considered to be extremely important.

Yet another important feature of the treated AOM composition 12 of the present invention is that the treated AOM composition 12 exhibits an anhydrous ignition loss value (LOI) substantially comparable to that of the untreated AOM composition. Is. The LOI value is an important parameter in the formulation of optically markingable ink compositions. The ability to maintain approximately equivalent LOI values in the treated AOM composition 12 of the present invention further demonstrates the further advantages of the treated AOM composition 12 of the present invention.

Various embodiments relating to the formation or production of the treated AOM powder composition 12 of the present invention, as well as the more important properties and advantages of the treated AOM composition 12 relating to the production of optically markingable inks and polymers. Although some of the above have been briefly described, here are detailed description of various preferred embodiments of the method for producing the treated AOM composition 12. However, before proceeding, the following description and the claimed process, unless otherwise indicated, may be any particular specific, such as the amount of reagents, the order of reagent additions, reaction conditions, and other numerical values. It should be noted that it should not be considered limited to operating parameters. Furthermore, specific reaction parameters and other operating factors can be optimized in certain circumstances (taking into account environmental factors, manufacturing scale requirements, etc.) using routine preliminary pilot tests. It should be noted. The discussion given herein includes one or more preferred embodiments designed to give optimal results and not considered limiting or limiting.

Here, with reference primarily back to FIGS. 1 and 2, the method 10 for producing the treated ammonium octamolybdate composition 12 is provided with an initial supply of ammonium octamolybdate (AOM) precursor material 14. Can be included. As previously mentioned, the compound called ammonium octamolybdate is also referred to as "diammonium catenatetramolybdate", "ammonium tetramolybdate", "tetraammonium hexamolybdate", or CAS number 12411-64-2. Usually known in various forms by. Therefore, the term "AOM" as used herein should be considered to include compounds known in various forms by these other names. In one aspect, the AOM precursor material 14 comprises an α-phase ammonium octamolybdate (α-AOM) powder material produced by thermal decomposition of ammonium dimolybdate (ADM), as described herein. .. Pyrolysis α-AOM is readily commercially available from a number of manufacturers and suppliers. By way of example, in the various embodiments and examples shown and described herein, the AOM precursor powder material 14 is pyrolyzed α-manufactured by Ft. Madison, IA (USA) Division of Climax Molybdenum Company. Includes AOM powder material.

The α-AOM precursor powder material 14 manufactured by the Climax Molybdenum Company is a fine powder with a bimodal particle size distribution 16 with two mode peaks 18 and 20, as best seen in FIG. Including. Before proceeding, the term "bimodal" as used herein refers to a particle size that includes two mode peaks that appear as maximal in a particle size difference plot or graph, or a separate particle size histogram plot or graph. It should be noted that it refers to the distribution. Similarly, the term "unimodal" refers to a particle size distribution containing a single mode peak or maximum value found in a particle size difference plot or a separate particle size histogram plot. In addition, the particle size distribution plots shown and described herein are formed by one or more different types of liquid dispersion type laser particle size analyzers, as specifically defined in the Examples section. It should be noted that The first type of analyzer is Orleans, France's Compagnie Industrielle des It was the Cilas particle size analyzer model No. 1180 manufactured by Lasers (Cilas). The second type of analyzer was the Microtrac particle size analyzer model No. S3000 / S3500 manufactured by Microtrac, Inc. of Montgomeryville, PA (USA).

Continuing the description here, the bimodal particle size distribution 16 of the α-AOM precursor material 14 used in the present invention is the first mode peak in the particle size range of about 1 to 4 μm (usually about 2 μm). Includes 18 and a second mode peak 20 with a particle size in the range of about 6-10 μm (usually about 8 μm). A scanning electron micrograph of the α-AOM precursor powder material 14 is shown in FIG.

After giving a suitable amount of AOM precursor material 14, solvent 22 can then be applied to the initial feed of precursor material 14 to form or produce a moist intermediate product 24. In one aspect, the solvent 22 can contain deionized water and can be added in an amount sufficient to produce a treated AOM composition having the desired monomodal particle size distribution. Alternatively, other types of solvents such as various alcohols and hydrocarbons 22 can be used. In embodiments where the solvent 22 comprises deionized water, the initial feed of precursor material 14 ranges from about 0.1% to about 1% by weight, preferably from about 0.25% to about 0.5% by weight, more preferably. Deionized water applied in an amount of about 0.5% by weight is sufficient for this purpose.

Solvent 22 can be applied in liquid form or as a gas or vapor (eg, water vapor 28). At this time, it is believed that when solvent 22 is applied to the AOM precursor material 14 (ie, in either liquid or vapor form), smaller particles bind or aggregate by a mechanism of capillary condensation. Capillary action is the result of the hydrophilicity of the AOM precursor material 14 and the relationship between the high surface area and the low gas volume at the interparticle site. The amount of moisture that can be condensed depends on the angle formed between the surfaces of the two particles and the amount of moisture available. In the presence of sufficient moisture (ie in the form of liquid or vapor), the solvent solubilizes in the material. AOM has a dissolution limit in water of about 4 grams / liter (g / L) at 25 ° C, which increases with temperature. Therefore, when exposed to moisture, small "bridges" of AOM are formed between the particles, which allow them to bind together with sufficient strength to hold them together after drying.

We have added about 0.5% by weight of water to the α-AOM precursor powder 14 without significantly increasing the anhydrous ignition loss (LOI) value of the resulting treated AOM composition 12. It was found that the bimodal particle size distribution 16 (Fig. 2) of No. 16 provides agglomeration of particles smaller than sufficient to convert to the monomodal particle size distribution 36 (Fig. 3). As an example, the treated α-AOM composition of the present invention can have a LOI value in the range of about 8% to about 8.8%. However, the addition of solvent 22 may apparently increase the dry weight loss (LOD) value of the resulting treated AOM composition 12.

As mentioned above, the solvent 22 can be applied to the AOM precursor material 14 in any variety of ways. In one embodiment, the solvent 22 (eg, water) is sprayed through one or more atomization nozzles 26 located adjacent to the AOM precursor material 14, as best seen in FIG. It can be added or applied to the initial supply of AOM precursor material 14 in liquid form. The atomizing nozzle 26 decomposes the liquid solvent 22 (for example, water) into fine droplets to form an atomizing stream 25. Dispersing the liquid water over one or more atomization streams 25 facilitates a more uniform distribution of the liquid water (ie, in the form of atomized droplets) across the AOM precursor material 14.

During the solvent application process, the method of applying the AOM precursor material 14 to the treatment, ie, whether the AOM precursor material 14 is deployed in a thin bed of material or given in bulk form containing a thicker bed of material. It may be desirable or advantageous to shake or rotate the AOM precursor material 14 to ensure a more uniform application of solvent 22 throughout the bulk of the precursor powder 14. In one aspect, such shaking or rotary agitation can be performed by placing the AOM precursor powder 14 in a drum-type rotary stirrer 34.

As an example, the rotary stirrer 34 can include a generally elongated cylindrical chamber or drum 40 mounted so as to rotate around a shaft 42. A drive motor 44 operably connected to the drum 40 can be actuated to rotate the drum 40 around a shaft 42 in the direction generally indicated by the arrow 46. The AOM precursor powder 14 is dug up and rotationally agitated as the drum 40 rotates by one or more blades or paddle members 48 provided over the inner surface 50 of the drum 40, thereby causing the precursor powder 14 to rotate. New particles are exposed to the atomized solvent 22 emitted from nozzle 26.

In another embodiment, the solvent 22 can be applied to the AOM precursor material 14 by first vaporizing the solvent 22, i.e. converting it to water vapor 28. A suitable steam generator device 30 can be used for this purpose. The water vapor 28 can then be applied to the AOM precursor powder 14 through one or more water vapor ports 32 located adjacent to the precursor material 14. In one aspect, the steam port 32 can be arranged within the rotary stirrer 34 to ensure uniform exposure of the precursor powder 14 to steam 28.

In some embodiments, it may be desirable to heat the precursor material 14 during the solvent application process. In such a case, the rotary stirrer 34 may be equipped with one or more heating units 52. The heating unit 52 can be started to provide the desired amount of heating at the desired time during the solvent application process. For example, in one embodiment, heating and application of steam can be performed together or alternately to produce the treated AOM composition 12. If heating is desired, temperatures in the range of about 80 ° C to about 105 ° C (more preferably about 100 ° C) can be used.

By applying solvent 22 to the initial feed of AOM precursor powder 14, a moist intermediate powder composition 24 is formed. The wet intermediate powder composition 24 is then adsorbed with the applied solvent 22 for a time sufficient to produce the AOM composition 12 treated as described above. Generally speaking, at least about 12 hours, more preferably about 48 to about 96 hours, is sufficient for this purpose. During the solvent adsorption process, some physical properties of the AOM precursor powder change significantly. For example, as the solvent is adsorbed by the AOM precursor powder 14, the particle size distribution of the AOM precursor powder 14 is from a substantially bimodal distribution 16 with two mode peaks 18 and 20 (FIG. 2). It changes or changes to a substantially monomodal distribution 36 with a single mode peak 38 (Fig. 3). Generally speaking, the treated AOM composition 12 has a single mode peak 38 in a diameter in the range of about 4 μm to about 12 μm, preferably in the range of about 6 μm to about 10 μm, more preferably in a diameter of about 8 μm. Have. The present inventors have found that the monomodal particle size distribution is much more important than the specific position of the monomodal peak. For example, all samples with single peaks in the range of about 6 μm to about 10 μm provided significant performance improvements.

In addition to a change or conversion of particle size distribution characteristics (eg, from substantially bimodal 16 to substantially monomodal 36), the surface of the individual particles of the AOM composition 12 treated by the treatment process 10. Changes in morphology or texture may also be brought about. For example, with reference primarily to FIGS. 4 and 5, scanning electron micrographs of the untreated AOM precursor powder 14 (FIG. 4) and the treated AOM composition 12 (FIG. 5) show the surface texture of the individual particles. Suggests that some changes have occurred. At this time, it is believed that changes in surface texture may have some impact on the improved performance of the treated AOM composition 12 when used in the formation of optically markable inks and polymers. ..

As mentioned above, method 10 can optionally include an additional treatment step on the wet intermediate material 24. For example, the moist intermediate product 24 can be further heated and / or dried in an oven or dryer 54. Such further heating can further reduce the level of residual moisture that may be contained in the intermediate product 24, which allows the dry weight loss (LOD) specification of the AOM composition 12 treated with it. It can also be reduced. When used, such heating should be carried out at any range of temperatures sufficient to dissociate the moisture, eg, temperatures in the range of about 80 ° C to about 100 ° C when water is used as the solvent 22. Can be done.

In addition, the intermediate product 24 also has a further grinding or grinding step with or without a further heating step 54 to destroy larger aggregates that may have formed during the treatment process. You can also call 56.

In this regard, some properties in the treated AOM composition 12 that may be necessary or desired in some applications, using some changes in the particular treatment steps and treatment parameters of Method 10. It should be noted that can be changed or changed. For example, the use of steam 28 instead of atomized water during the solvent application process usually results in a treated AOM composition 12 having a slightly smaller maximum particle size. The use of water vapor 28 can also reduce the particle size associated with the second mode peak 20 of the treated material 12. Furthermore, although not required to produce the treated AOM composition 12, heat can be applied to reduce the time required to produce the processed AOM composition 12. To reduce the dry reduction (LOD) specification of the final processed AOM composition 12 by applying heat either during the solvent application process or to the moist intermediate product 24 formed thereby. It can also be desirable in some applications.

In another aspect 110 shown in FIG. 19, the solvent 122 can be applied to the AOM precursor material 114 with the intermediate adsorbent 123. More specifically, the solvent 122 can be applied to the intermediate adsorbent 123 to form the intermediate adsorbent 123 containing the solvent. The solvent-containing intermediate adsorbent 123 can then be placed in a gas permeable container or bag 125. The solvent-containing intermediate adsorbent 123 can then be placed in the container 135 with a constant amount of AOM precursor material 114 (along with the gas permeable bag 125 if used). The container 135 can then be sealed (eg, substantially airtight). The solvent 122 from the solvent-containing adsorbent 123 is gradually desorbed (and if used) from the intermediate adsorbent 123 before being adsorbed by the AOM precursor material 114 to form the wet intermediate powder composition 124. Pass through a permeable container or bag 125). The desorption / adsorption process can be continued for a time sufficient to produce the processed AOM composition 112. During the desorption / adsorption process, the particle size distribution of the AOM precursor material 114 is changed or transformed from a substantially bimodal particle size distribution to a substantially monomodal particle size distribution.

As with other embodiments, the solvent 122 can contain any wide range of materials, such as water, alcohol, or hydrocarbon materials. The intermediate adsorbent 123 is any wide range suitable for adsorbing a particular solvent 122 and then desorbing or dissociating a certain amount of solvent 122 when the adsorbent 123 is placed in a closed container 135. Materials can be included. As an example, in one embodiment, the solvent 122 comprises deionized water and the intermediate adsorbent 123 comprises amorphous precipitated silica (ie silica gel). The solvent 122 (eg, deionized water) and the silica gel adsorbent 123 desorb a sufficient amount of the solvent 122 from the adsorbent 123 and then adsorb it with the AOM precursor material 114 to produce the treated AOM composition 112. Must be given in sufficient quantity. Generally speaking, it is sufficient to add an intermediate adsorbent 123 having an adsorbed solvent (eg, water) ranging from about 0.3% to about 0.5% by weight of the total amount of AOM precursor material 114 to be treated.

As with method 10, method 110 may optionally include additional processing steps. For example, to further reduce the level of residual moisture that may be contained in Intermediate Product 124 and / or to further reduce the dry weight loss (LOD) specification of the treated AOM composition 112. The intermediate powder 124 can be further heated and / or dried in the oven or dryer 154. When used, such heating is any wide range sufficient to dissociate the moisture, such as temperatures in the range of about 80 ° C to about 100 ° C when using deionized water as the solvent 122. Can be done at the temperature of.

Intermediate product 124 is also subjected to additional grinding or grinding step 156 with or without additional heating step 154 to decompose larger aggregates that may have formed during the treatment process. You can also do it.

In yet another embodiment 210 shown in FIG. 20, the treated AOM composition 212 has a constant amount of time sufficient to change the particle size distribution from a bimodal distribution to a substantially monomodal distribution. It can be produced by heating the AOM precursor material 214 of. In such embodiment 210, the AOM precursor material 214 must contain a sufficient level of retained moisture to allow the treated AOM composition 212 to be produced. Generally speaking, we have a moisture retention level corresponding to a dry weight loss (LOD) in the range of at least about 0.10% by weight, more preferably about 0.10% to about 0.2% by weight. It has been found that the AOM precursor material 214 is sufficient to produce a treated AOM composition 212 having the desired monomodal particle size distribution.

The treated AOM composition 212 places a constant amount of AOM precursor material 214 (ie, having a sufficient level of retained moisture as measured by LOI (% by weight)) in the container 235 and the container 235. It can be produced by sealing and making it substantially airtight. Next, in step 253, the closed container 235 is treated with a treated AOM having the desired unimodal particle size distribution at a temperature of at least about 30 ° C, more preferably about 30 ° C to about 50 ° C. It can be heated for a time sufficient to produce the composition 212. Generally speaking, heating 253 performed for a time ranging from at least about 7 days, more preferably about 7-10 days is sufficient for this purpose.

Importantly, we have recirculated the retained moisture in the AOM precursor material 214 during the treatment process, thereby making it extremely "new", i.e. the most recently pyrolyzed AOM precursor material 214 ( It has been found that (ie having a low moisture content) can provide sufficient moisture for the treatment process. That is, the moisture adsorbed into smaller particles during the capillary condensation process tends to be dissociated after the aggregation process, which allows the moisture to be utilized for further capillary condensation at other particle sites. it can. For example, after sealing in container 235, most AOM precursor materials 214 have been treated with relative humidity in the closed container 235 within a reasonable amount of time (eg 7-10 days). Contains enough retained moisture to raise to a level in the range of 80-100%, which is sufficient to produce.

Method 210 may optionally include additional processing steps. For example, the treated AOM powder product 212 can be subjected to a further grinding or grinding step 256 to decompose larger agglomerates that may have formed during the treatment process.

Treated AOM compositions, such as 12, 112, 212, can be used to benefit in the production of AOM-based optically markingable inks and polymer compositions. In one embodiment, the treated AOM compositions 12, 112, 212 are used with the conventional AOM required for a particular formulation to achieve one or more performance improvements and advantages described herein. Can be replaced in part or in whole.

<p num="0055"> Α-treated according to the teachings given herein by three variations of the disclosed treatment process 10, referred to herein as "floor steam treatment", "rotary dryer steam treatment", and "solvent spraying" process. Compositions of various examples of AOM product 12 were made. In the floor steam treatment process, a thin layer or floor of α-AOM precursor material is placed in a shallow vessel or "boat", which is then placed at 100 ° C. at 100% relative humidity as further described below. Placed in the oven. The processed AOM composition 12 produced by the rotary dryer steam treatment process places the α-AOM precursor material 14 in a rotary dryer or rotary stirrer 34 provided therein with a steam port 32. Obtained by that. Finally, the treated AOM composition 12 produced by the solvent spray process was obtained by exposing the α-AOM precursor material 14 to a spray of atomized water 25 in a rotary stirrer 34. Further details regarding the specific process parameters, precursor materials, and processed products for the various processing processes are given below.</p><p num="0056"> Floor steam treatment process: Five separate experiments, referred to here as Experiments 1-5, were performed to prepare the treated α-AOM composition 12 from two different types of α-AOM precursor powder material 14. In the first four experiments (ie, Experiments 1-4), commercially available or "standard" α-AOM precursor material 14 was used. The standard α-AOM precursor material 14 showed a bimodal particle size distribution 16 (Fig. 2) typical of such material 14. The standard α-AOM precursor material 14 is treated either partially (for Experiments 1 and 2) or completely (for Experiments 3 and 4) and the corresponding partially or completely treated α. -AOM composition was produced. Experiment 5 involved treating the "superground" α-AOM precursor material 14. The ultra-milled precursor material was further milled in a hammer mill to produce the precursor material 14 having the nearly unimodal particle size distribution best shown in FIG.</p><p num="0057"> Table I gives some properties of two different types of α-AOM precursor powder material 14 (ie, standard and ultra-milled). Particle properties were obtained by mixing a small sample of each α-AOM precursor material with isopropyl alcohol and analyzing the mixture with a Cilas laser particle size analyzer. The Cilas particle size analyzer also produced a corresponding particle histogram and a plot of the integrated sieve particle distribution, which are shown in Figures 2 (for standard α-AOM precursor powder material) and Figure 6 (supermilled α- Reproduced in (for AOM precursor powder material).</p><p num="0058"><tables num="1"><img id="000003" he="81" wi="147" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0059"> All experiments (ie, Experiments 1-5) were subjected to steam and / or heat to both types of α-AOM precursor material 14 (ie, standard and superground precursor materials) as described below. Included in the production of various experimental compositions. As described herein, Experiments 1 and 2 included partially treating the standard α-AOM precursor material 14 to produce a partially treated α-AOM powder composition. Experiment 1 included partial treatment of the standard precursor material 14 first, while Experiment 2 included further treatment of the composition of Experiment 1. The particle size data for the compositions of Experiment 1 and Experiment 2 are shown in Table II. The particle size histograms of the compositions of Experiments 1 and 2 are reproduced in FIGS. 7 and 8, respectively, showing the gradual progression of the powder from a bimodal particle size distribution to a monomodal particle size distribution.</p><p num="0060"> Experiment 3 involved completely treating the standard α-AOM precursor material 14 to produce a fully treated α-AOM composition 12. Grain size data for the fully treated α-AOM composition of Experiment 3 is also shown in Table II. The particle size histogram of the composition of Experiment 3 is reproduced in FIG.</p><p num="0061"> Experiment 4 also included complete treatment of standard α-AOM precursor material 14, but with a larger sample size (1 kg) compared to the smaller sample sizes of Experiments 1-3 (50 g precursor material 14). Precursor material 14) was included. Particle size data and histograms of the three individual samples of the fully treated AOM composition of Experiment 4 are shown in Table III and in Figures 3, 10 (a) and 10 (b), respectively.</p><p num="0062"> Experiment 5 included complete treatment of 100 g of superground α-AOM precursor material 14. Particle size data and histograms of the three individual samples of the fully treated AOM composition of Experiment 5 are shown in Table IV and FIGS. 11 (a-c).</p><p num="0063"> Experiments 1 and 2: As mentioned above, Experiments 1 and 2 included partial treatment of 50 g of standard α-AOM precursor powder material 14. The standard α-AOM precursor material 14 contained a heat loss or dried α-AOM commercially available from the Ft. Madison division of the Climax Molybdenum Company as described herein. A 50 g sample of standard α-AOM precursor material 14 is spread in a thin layer or floor in a shallow uncovered container and placed in a 100 ° C oven with a container of boiling water in it. Placed. Boiling water in the oven was used to maintain a relative humidity of approximately 100% during the treatment process. The precursor material 14 was heated and subjected to such steam treatment for about 6 hours to produce a partially treated AOM powder composition. The partially treated AOM powder composition of Experiment 1 was then removed from the oven and cooled and dried at room temperature for approximately 1 hour. A small sample of the composition of Experiment 1 was then mixed with isopropyl alcohol and analyzed with a Cilas laser particle size analyzer as described herein.</p><p num="0064"> Experiment 2 was a continuation of Experiment 1 and included returning the composition of Experiment 1 to the oven and subjecting the composition to further heating at 100 ° C and 100% relative humidity. The composition of Experiment 2 was heated and exposed to steam for an additional 8 hours. The partially treated composition of Experiment 2 was then removed from the oven and cooled and dried at room temperature for approximately 1 hour. Next, a small portion of the composition of Experiment 2 was mixed with isopropyl alcohol and analyzed with a Cilas laser particle size analyzer.</p><p num="0065"> The particle size data for Experiments 1 and 2 are shown in Table II. Particle histograms for the powder compositions of Experiments 1 and 2 are reproduced in Figures 7 and 8, respectively. As can be seen from the histogram, the partial treatment of the AOM precursor material 14 increases the treatment time and gradually reduces the intensity of the two mode peaks. However, it should be noted that for the composition of Experiment 2, additional mode peaks appeared at a particle size of about 0.3 μm. The appearance of this mode peak is considered to be the result of decomposition of agglomerated particles by the sonicator of the Cilas laser particle size analyzer.</p><p num="0066"> Experiment 3: The procedure for Experiment 3 was similar to that used for Experiments 1 and 2, except that Experiment 3 included complete treatment of 1 kg of standard α-AOM precursor material 14. The standard α-AOM precursor material 14 also contained a heat loss or dried α-AOM powder commercially available from the Climax Molybdenum Company described herein. Standard α-AOM precursor material 14 was developed in a thin layer or floor in a shallow lidless container and heated in an oven at 100 ° C. for about 70 hours at 100% relative humidity. The fully treated AOM composition of Experiment 3 was then removed and cooled and dried at room temperature for about 2 hours, but the cooling time is not important.</p><p num="0067"> Next, a small sample of the composition of Experiment 3 was mixed with isopropyl alcohol and analyzed with a Cilas laser particle size analyzer. The particle size data for the sample in Experiment 3 is also shown in Table II. The corresponding particle size histogram is reproduced in Figure 9. The sample of Experiment 3 is also completely monomodal except for the mode peak at about 0.3 μm. Again, the presence of the mode peak at about 0.3 μm is considered to be the result of the action of the sonicator of the laser particle analyzer.</p><p num="0068"><tables num="2"><img id="000004" he="87" wi="157" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0069"> Experiment 4: Experiment 4 included treatment of 1 kg of standard α-AOM precursor material 14. The standard α-AOM precursor material 14 again contained a heat loss or dried α-AOM from the Climax Molybdenum Company. AOM precursor material 14 was deployed in a thin floor in a shallow lidless container and placed in an oven at 100 ° C. with a container of boiling water in it. AOM precursor material 14 was retained at 100 ° C for approximately 72 hours in an atmosphere of 100% relative humidity. Next, the composition of Experiment 4 was dried at a heating temperature of 105 ° C.</p><p num="0070"> Next, three individual samples of the composition of Experiment 4 were mixed with isopropyl alcohol and analyzed with a Cilas laser particle size analyzer. The particle size data for the three samples of the composition of Experiment 4 are shown in Table III. Particle size histograms for the three samples are reproduced in Figures 3, 10 (a), and 10 (b).</p><p num="0071"> As can be seen from the histograms for the three samples, the composition of Experiment 4 is completely monomodal, with modal peaks for various samples appearing in particle sizes ranging from about 5 μm to about 6 μm. Note that none of the histograms of the three samples of the composition of Experiment 4 show mode peaks at smaller particle sizes. It is probable that the sample of the composition of Experiment 4 did not undergo particle decomposition by sonication during the measurement process.</p><p num="0072"><tables num="3"><img id="000005" he="85" wi="158" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0073"> Experiment 5: Experiment 5 included treatment of approximately 100 g of "superground" α-AOM precursor material 14. The ultra-crushed α-AOM precursor material 14 is obtained by grinding standard heat loss or dried α-AOM from the Climax Molybdenum Company in a hammer mill until the particle size distribution is almost monomodal. Manufactured by. See Figure 6. The ultra-crushed α-AOM precursor material 14 was developed in a thin floor in a shallow lidless container and placed in an oven at 100 ° C. with a container of boiling water. The superground α-AOM precursor material 14 was kept in an atmosphere of 100% relative humidity at 100 ° C. for about 72 hours. Next, the composition of Experiment 5 was dried at a heating temperature of about 105 ° C. Next, three individual samples of the composition of Experiment 5 were mixed with isopropyl alcohol and analyzed with a Cilas laser particle size analyzer. The particle size data for the three samples of the composition of Experiment 5 are shown in Table IV. The particle size histograms for the three samples are reproduced in FIGS. 11 (a to c).</p><p num="0074"> The composition of Experiment 5 is completely monomodal, with modal peaks appearing at a particle size of about 10 μm for various samples. As with the composition of Experiment 4, the histograms of the three samples of the composition of Experiment 5 also show no mode peaks at smaller particle sizes. It is probable that the sample of the composition of Experiment 5 also did not decompose particles by sonication during the measurement process.</p><p num="0075"><tables num="4"><img id="000006" he="85" wi="158" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0076"> Rotating dryer steam treatment process: The steam treatment process of the rotary dryer included placing a constant amount of AOM precursor powder material 14 in a rotary drum rotary stirrer 34 and exposing the precursor material 14 to steam with rotary stirring. The resulting moist intermediate powder product 24 was then removed from the rotary stirrer 34 and dried. No heat was applied to the sample during or after the steam treatment process.</p><p num="0077"> This particular example included treatment of approximately 2 kg of standard AOM precursor powder material 14. The standard α-AOM precursor material 14 again contained a heat loss or dried α-AOM from the Climax Molybdenum Company. The particle size data and histogram of the α-AOM precursor material are shown in Table V and FIG. 12, respectively. It should be noted that the particle size data and histograms for the rotary dryer steam treatment process were formed by the Microtrac particle size analyzers described herein. The AOM precursor material 14 was then placed in a rotary stirrer 34 and exposed to water vapor. After rotary stirring and steam treatment, the wet intermediate powder 24 was removed from the rotary stirrer 34.</p><p num="0078"> Next, a sample of the composition steam-treated with a rotary dryer was mixed with isopropyl alcohol and analyzed with a Microtrac laser particle size analyzer. The particle size data for this sample composition is shown in Table V. The particle size histogram for this sample is reproduced in FIG.</p><p num="0079"> As can be seen from the histogram for the sample, the composition steamed in a tumble dryer is predominantly monomodal and has a mode peak that appears at a particle size of about 10 μm. Note that the histogram of the composition steamed in a tumble dryer shows a small mode peak at about 0.2 μm. Again, the appearance of this mode peak is considered to be the result of decomposition of the agglomerated particles by the sonicator of the Microtrac laser particle size analyzer.</p><p num="0080"><tables num="5"><img id="000007" he="84" wi="157" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0081"> Solvent spraying process: The solvent spraying process involved placing a constant amount of AOM precursor powder material 14 in a rotary drum rotary stirrer 34 and exposing the precursor material 14 to an atomized spray of water with rotary stirring. The moist intermediate powder product 24 was then removed from the rotary stirrer 34 and dried. No heat was applied to the sample during or after the solvent spraying process.</p><p num="0082"> Four separate experiments (Experiments 1-4) were performed in which the treated α-AOM composition 12 was prepared from the pretreated α-AOM precursor powder material. The pretreated α-AOM powder material was made from standard α-AOM precursor material, to which 0.14 wt% water was added. The particle data for the pretreated precursor material is shown in Table VI. The particle histogram of the pretreated material is reproduced in FIG. Particle data and histograms for the materials involved in the solvent spray process were formed by a Microtrac laser particle size analyzer.</p><p num="0083"> As can be seen from FIG. 14, the pretreated α-AOM material has a bimodal particle size distribution, with a small third peak at a particle size of about 0.3 μm, which is here. However, it is considered that this is the result of decomposition of agglomerated particles by the sonicator of the laser particle size analyzer.</p><p num="0084"><tables num="6"><img id="000008" he="91" wi="111" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0085"> Experiments 1 to 4 produce treated α-AOM compositions by adding varying amounts of water (ie, in the form of atomized spray) to the pretreated α-AOM material, as shown in Table VII. Included. After adding water, the resulting moist intermediate powder 24 was removed from the rotary stirrer 34.</p><p num="0086"> A small amount of sample from each of the four experimental compositions was then mixed with isopropyl alcohol and analyzed with a Microtrac laser particle size analyzer. The particle size data for the sample composition is shown in Table VII. The particle size histograms of the compositions of Experiments 1 to 4 are reproduced in FIGS. 15-18, respectively, showing the gradual progression of the powder from a bimodal particle size distribution to a monomodal particle size distribution. Note that the histogram for the composition produced by the solvent spray process also shows a small mode peak at a small particle size of about 0.2 μm. Again, the appearance of these mode peaks is considered to be the result of decomposition of the agglomerated particles by the sonicator of the laser particle size analyzer.</p><p num="0087"><tables num="7"><img id="000009" he="100" wi="164" file="JP2016507635A_D0001.tif" img-format="tif" img-content="drawing" /></tables></p><p num="0088"> Intermediate adsorbent process: Another example included process 110 in which solvent 122 was first applied to intermediate adsorbent 123. The intermediate adsorbent 123 containing the resulting solvent was then placed in a sealed container 135 with the AOM precursor material 114. The AOM precursor material 114 also contained a heat loss or "dried" α-AOM powder from the Climax Molybdenum Company, as shown herein. The AOM precursor material 114 had the typical bimodal particle size distribution described above for other AOM precursor materials. In this example, deionized water was added to about 28 g of silica gel adsorbent 123. Silica gel adsorbent 123 absorbed about 30-35% by weight of deionized water, which was consistent with theoretical values for silica gel at its temperature and 100% humidity. The resulting solvent-containing silica gel intermediate adsorbent 123 (contained in a gas permeable bag 125) was then placed in container 135 with about 100 g of AOM precursor material 114. The container 135 was then sealed (ie, substantially airtight) and held at room temperature (ie about 22 ° C) for about 120 hours (about 5 days).</p><p num="0089"> Before proceeding, it should be noted that the amount of silica gel intermediate adsorbent 123 used in this example was much higher than the amount normally used in one embodiment of the invention. There were two reasons for this. First, to determine if the AOM precursor material 114 produces a paste-like material by supersaturation by this method; second, how much from the silica gel intermediate adsorbent 123 under conditions where AOM is not optimal. This was to determine whether to adsorb moisture. The silica gel intermediate adsorbent 123 contained much more solvent 122 (ie water) than would be required for the treatment process, but the AOM precursor material 114 did not become a paste. Subsequent analysis showed that the silica gel intermediate adsorbent 123 dissociated about one-third (ie, 33%) of the adsorbed solvent 122, which was about 3 by weight of the treated AOM material 112 in total. It means that it contained ~ 4% water. On a large scale, the addition of silica gel intermediate adsorbent 123, which is added in an amount sufficient to add water between about 0.3% by weight and about 0.5% by weight, gives good results.</p><p num="0090"> Continuing the description here, a small sample of the resulting treated AOM material 112 was then mixed with isopropyl alcohol and analyzed with a Cilas particle size analyzer. The obtained particle size histogram is reproduced in FIG. As can be seen from the histogram, the particle size distribution of the treated AOM material 112 was substantially monomodal and had a modal peak at about 7 μm. Note that additional mode peaks appeared at a particle size of about 0.2 μm. Again, the appearance of this mode peak is considered to be the result of decomposition of the agglomerated particles by the sonicator of the laser particle size analyzer.</p><p num="0091"> In conclusion, the claimed products and processes show significant advances in molybdenum technology overall. The treated AOM compositions described above are not only characterized by having a substantially monomodal particle size distribution that is difficult to achieve by conventional methods, but also untreated AOM compositions. Produces an optically markable ink composition having superior performance and harmony as compared to a composition produced from. The treatment methods described herein make it possible to produce large quantities of treated AOM compositions characterized by a uniform particle size distribution.</p><p num="0092"> Although preferred embodiments of the present invention have been shown herein, suitable modifications can be made to it, which are still believed to remain within the scope of the invention. Therefore, the present invention is construed only according to the claims.</p>