Production of high purity titanium suboxide

[Detailed Description of the Invention]

[Industrial Application] The present invention relates to the manufacturing method of high purity titanium suboxide using the reduction reaction by a solid phase-solid phase materials system. [Description of the Prior Art] Since blackish brown and which gray or black color tone are presented by reduction unlike a titanium dioxide and also it has good electric conduction performance, the object for Existence of the titanium suboxide is carried out as a conductive filler of color paints or various materials. How to carry out high temperature reduction of the titanium dioxide by gas, such as hydrogen or ammonia, as a means to manufacture this titanium suboxide conventionally (JP,59-50604,B) The method of heating the mixture of titanium dioxides, such as JP,57-205322,A, and titanium metal in a vacuum or a reduction atmosphere is known as typical art. Among these, the former method uses the reduction reaction by a solid phase-gaseous phase materials system, and although the titanium suboxide obtained is average particle diameter 0.05~0, and 3 micrometers and detailed quality, an in-house has a problem that reducing gas, such as hydrogen or ammonia, remains. On the other hand, the latter method uses the reduction reaction by a solid phase-solid phase materials system, and is indicated by JP,49-5432,A, for example. It is considered as important requirements for setting to 10 or less am the particle size of the titanium metal which serves as a starting material in the method of using this solid phase-solid phase materials system to advance a reaction smoothly, and is general, Although methods, such as carrying out machinery pulverization of the titanium metal obtained by carrying out sodium reduction of mechanical pulverization of titanium sponge or the 4 titanium oxide for powder-izing titanium metal with the salt which is a reaction product, are taken, The limit of the degree of crushed grain by these methods is about at most 149 micrometers, and it is difficult to acquire a particle size level [ aptitude / as materials ]. There is the method of carrying out dehydration of the titanium hydride powder obtained by once grinding titanium sponge as a fine grinding means of titanium metal superior to this after hydrogenating. however -- the case where it is based on this method -- pulverization-Sieve -- it is necessary to carry out by repeating another process, and there is a fault which causes contamination of the secondary impurities from crushing equipment etc., especially mixing of iron in this process. [Problem(s) to be Solved by the Invention] Recently, vapor deposition of titanium oxide is performed in fields, such as an optical system and opto-electronics. Titanium suboxide is used also as vapor deposition material of this object by the relation with high steam pressure as compared with the titanium dioxide. Although vacuum deposition formation of the titanium suboxide used for vapor deposition material is carried out as a titanium oxide thin film in a substrate side after dissolving by resistance heating or an electron beam heating, In this case, in a vapor deposition process, it cannot fuse uniformly that titanium suboxide is fine powder too much, but the phenomenon in which one kimono disperses arises. If the splash and out gas in a vacuum heating state are large, the trouble which a vapor deposition thing adheres to an evaporation apparatus, or an electron gun filament oxidizes and uniform vapor deposition is not not only made at a substrate, but deteriorates will occur. If a lot of impurities contain in titanium suboxide, the refractive index of a vapor deposition film will be changed and it will become Cause which degrades tunic performances -- an absorption feature becomes large. Therefore, the quality characteristic required of titanium suboxide aiming at vapor deposition material is in the particle state which is seldom fine powder, and is that there is little content of gas constituents and impurities as much as possible. If the titanium suboxide obtained by the conventional production technology mentioned above is made to contrast with this demand characteristic, since existence of occluded gas and particle diameter are too small when based on a solid phase-gaseous phase system, it is unsuitable, and in the case of a solid phase-solid phase materials system, there will be much impurities content, and it will satisfy neither of the cases. The present invention cancels the problem of the above conventional technologies, and provides the manufacturing method of high purity titanium suboxide with which it may be satisfied of the demand characteristic also to the vapor deposition material object. [Means for solving problem] Namely, conventional technology is a manufacturing method of the high purity titanium suboxide which used different solid phase-solid phase materials systems, and the present invention is the composition, In the temperature region of 700~1600 degreeC, heating calcination of the mixture of titanium hydride powder with a particle size of 80 micrometers or less and a titanium dioxide is carried out under a vacuum or inactive gas atmosphere. Titanium hydride used as the starting material of the present invention is powder-ized as follows. Granular titanium hydride is heated to the temperature of 400~700 degreeC in a hydrogen atmosphere. The state after cooling is converted into the same quality as heating before that can be easily pulverized by hydrogen embrittlement though it is granular. Pulverization can be performed using a usual grinder like a ball mill and a vibrating mill. When a powdered particle size becomes larger than 80 micrometers, the reduction reaction in a calcination process becomes uneven, and it becomes impossible to obtain titanium suboxide of fixed composition. Therefore, as for particle size adjustment of titanium hydride, it is more appropriately desirable to use 50 micrometers or less 80 micrometers or less. In order to grind in particle size of 50 micrometers or less, it ends with the case where a vibrating mill is used about 10~30 minutes by a ball mill, extremely with about 5~20 minutes for a short time, and can also perform comparatively easily particle size adjustment not more than it. Thus, the titanium hydride powder of 80 micrometers or less which carried out particle size adjustment is mixed with a titanium dioxide by a predetermined compounding ratio. Since the hydrogen ingredient which constitutes titanium hydride is finally removed as gas in a calcination process, after the compounding ratio of titanium hydride and a titanium dioxide considers the hydrogen which vaporizes as gas, it is set up. For example, the reaction at the time of generating TiO among titanium suboxide is based on a following formula. T i O+T i Hz->2 T i O+H, ↑, for this reason a compounding ratio serve as 38.44 % of the weight of T i Hz, and Ti Ox 61.56%. However, it becomes possible by changing this compounding ratio and controlling the degree of reduction to obtain various kinds of low order titanium oxide, such as Tt, O, Ti, and O. The mixture or the kneading apparatus ordinarily used by dry type or a Warm type method can perform mixture of titanium hydride powder and a titanium dioxide. As for a mixture, it is preferred to fabricate to a pellet type beforehand before heating calcination. Although carried out using the press molding apparatus of usual oil or mechanical type, in order that a metallic mold may gnaw fabrication and it may improve prevention and a mold-release characteristic, it is Response(ed) by necessity and may add a proper binder component. When the heating temperature performed in the temperature region of 700~1600 degreeC using an electric furnace etc. is less than 700 degreeC, a reduction reaction does not advance smoothly, but a heating calcination process becomes difficult [ it / to obtain titanium suboxide of fixed composition ]. On the other hand, if it heats at the temperature exceeding 1600 degreeC, the amount of evaporation of titanium suboxide will increase and yield will fall sharply. Although it is necessary to hold the atmosphere at the time of calcination in an inactive atmosphere like a vacuum or argon, and a helium, in order to remove the hydrogen content in titanium suboxide effectively, maintaining at a vacuum atmosphere is desirable. It cools in the state where it held in a vacuum or inactive gas atmosphere, and after heating calcination takes out as a product the titanium suboxide which carried out reaction generation. [For Work ] Since selection use of the titanium hydride is carried out as a starting material used as a reducing agent according to the present invention, the pulverization to a predetermined particle size becomes very easy. For example, the time required which pulverization of the same particle size takes can be shortened to 1/2~l/10 compared with the time of grinding a titanium metal lump. Therefore, the impurities mixed from a device etc. in a pulverization process can be pressed down at worst. the hydrogen gas which a reduction reaction advances smoothly and carries out reaction generation in a heating calcination process -- the in-house of titanium suboxide -- occlusion Monkey -- it vaporizes without things. It functions, in order that these mechanisms may always manufacture titanium suboxide with little gas content efficiently in high purity conjointly with the operation of particle size limitation (80 micrometers) of titanium hydride. [Example] Hereinafter, an example and a comparative example explain the present invention. Example 1 The particle size of 44 micrometers or less (average particle diameter of 7*6 micrometers by an optical penetration method), hydrogen content! 3.85% of titanium hydride powder 769g and 1231 g of titanium dioxide powder (average particle diameter of 0.60 micrometer by an optical penetration method) were blended, and it mixed for 30 minutes with the dry blending machine. This end of mixed powder was fabricated by the pressure of 300 kg/c+! using the hydroforming press, and it was considered as the tablet form pellet of diameter 10 m+a and thickness 4 big building. Subsequently, the titanium suboxide by which heating calcination might be carried out for 3 hours at the temperature of 1300 degreeC is a substance which assumes a brownish black color, filling up a vacuum atmosphere furnace with 2 kg of Peret, and holding the inside of a furnace to the degree of vacuum of 6.OX 10-'To r r, and it was checked that it is TiO as a result of an X diffraction. Content impurities were measured per this titanium suboxide, and it was shown in Table 1. Example 2 Titanium suboxide was manufactured according to the same conditions as Example 1 except [ all ] having used the compounding ratio as titanium hydride powder 345g and titanium dioxide powder 1655g. The obtained titanium suboxide was assuming a black color, it TizO(ed) and came out as a result of the X diffraction, and a certain thing was accepted. Content impurities were measured simultaneously and it was shown in Table 1. Example 3 Titanium suboxide was manufactured according to the same conditions as Example 1 except [ all ] having used the compounding ratio as titanium hydride powder 222g and titanium dioxide powder 1788g. The obtained titanium suboxide is assuming a black color and it was checked that it is T i 30 s as a result of an X diffraction. The content impurities were measured and it was shown in Table 1. Comparative example 1 The vacuum atmosphere furnace was filled up with 8 kg of the same titanium hydride as Example 1, and it held to the temperature of 700'C under the vacuum for 2 hours. The last ultimate pressure in this case was 1.5X 10-"Torr. The obtained massive titanium metal was broken by the mortar made from stainless steel among argon atmosphere after cooling, and it ground for about 40 minutes in the amount of about 0.6kg/minute feeding among argon atmosphere using the continuation vibrating mill succeedingly. The part class was carried out by Sieve with a particle size of 44 micrometers after pulverization, on Sieve, grinding treatment of 2 kg of the titanium metal was again carried out by the continuation vibrating mill, and it was altogether adjusted to the particle size of 44 micrometers or less. The average particle diameter by this optical penetration method was 20.6 micrometers. Subsequently, it mixed according to Example 1 and fabricated the same titanium dioxide powder 1250g as titanium metal powder 750g and Example 1 to Vered. The vacuum atmosphere furnace was filled up with 2 kg of this pellet, and heating calcination was carried out for 3 hours at the temperature of 1300 degreeC, holding the inside of a furnace to the degree of vacuum of 5.2X 10-'Torr. The obtained titanium suboxide is presenting the color tone of the brownish black color, and it was checked that it is TiO as a result of an X diffraction. Content impurities were measured about this titanium suboxide, and it carried jointly in Table 1. Comparative example 2 Titanium suboxide was manufactured on the same conditions as comparative example 1 except [ all ] having used the compounding ratio as titanium hydride powder 333g and titanium dioxide powder 1667g. The obtained titanium suboxide was black and it was checked that it is 'pifoff as a result of an X diffraction. Measurement of content impurities was also performed and the analysis result was carried jointly in Table 1. comparing each example of the present invention with a comparative example from the result of Table 1 -- un-'I / 1. -- a snout -- content is decreasing and it becomes clear that especially the iron ingredient is decreasing remarkably. Effect] of [invention The manufacturing method of the present invention guarantees the thing with little gas content acquired titanium suboxide 1 in high purity quickly and smoothly by the process shortened by using titanium hydride for a starting material. Therefore, the use field which can be applied also becomes extensive and becomes industrial very advantageous.