Classifications

• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
  • C04B28/18—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing mixtures of the silica-lime type
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
  • B01J20/10—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising silica or silicate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
  • B01J20/28002—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their physical properties
  • B01J20/28004—Sorbent size or size distribution, e.g. particle size
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
  • B01J20/28014—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
  • B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
  • B01J20/28078—Pore diameter
  • B01J20/28085—Pore diameter being more than 50 nm, i.e. macropores
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
  • B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
  • B01J20/28095—Shape or type of pores, voids, channels, ducts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/30—Processes for preparing, regenerating, or reactivating
  • B01J20/305—Addition of material, later completely removed, e.g. as result of heat treatment, leaching or washing, e.g. for forming pores
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
  • C04B38/0051—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity
  • C04B38/0064—Multimodal pore size distribution
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C11/00—Use of gas-solvents or gas-sorbents in vessels
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C11/00—Use of gas-solvents or gas-sorbents in vessels
  • F17C11/002—Use of gas-solvents or gas-sorbents in vessels for acetylene
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
  • C04B2111/00948—Uses not provided for elsewhere in C04B2111/00 for the fabrication of containers

Definitions

• the present invention relates to a novel ceramic porous material, the method of manufacturing this new material, containers containing it, and the use of containers for storing fluids such as gases and / or liquids.
• pressurized containers containing gases such as acetylene, dissolved in a solvent, such as acetone or DMF, in various applications, and in particular for carrying out welding, brazing and heating operations. in combination with a bottle of oxygen;
• These containers are usually filled with solid filling materials, intended to stabilize the gases they contain, which are thermodynamically unstable under the effect of pressure variations and / or temperature and therefore likely to decompose during storage, their transport and / or their distribution.
• These materials must have sufficient porosity to facilitate the adsorption and release of the gases contained in the container. They must also be incombustible, inert vis-à-vis these gases and have good mechanical strength.
• These materials are conventionally made of porous silica-based ceramic masses, obtained for example from a homogeneous mixture in quicklime water or milk of lime and silica (in particular in the form of quartz flour), as described in FIGS. WO-A-93/1601 1, WO-A-98/29682, EP-A-262031, to form a mash which is then subjected to hydro-thermal synthesis.
• the mash is introduced into the container to be filled, under partial vacuum, which is then subjected to pressure and temperature autoclaving, then to baking in an oven to completely remove the water and form a monolithic solid mass of composition Ca x Si y O z , w.H 2 O presenting crystalline structures of the tobermorite and xonotlite type, with a possible residual presence of quartz.
• Various additives can be added to these mixtures of the prior art to improve the dispersion of lime and silica and thus avoid the formation of structural inhomogeneities and shrinkage phenomena observed during hardening of the porous mass.
• the filling materials obtained must in fact have a homogeneous porosity without voids in which pockets of gas could accumulate and lead to explosion hazards.
• EP-A-264550 furthermore indicates that a porous mass containing at least 50%, or even at least 65%, or even at least 75% by weight of crystalline phase (relative to the weight of calcium silicate) makes it possible to meet the dual requirement of compressive strength and shrinkage at hydrothermal synthesis and cooking temperatures.
• the container having a diameter / length ratio of between 0.2 and 0.7, preferably between 0.35 and 0.5, for a minimum water capacity of one liter and preferably between 3 and 10 liters.
• This deficiency is particularly related to the significant pressure drop generated by the microstructure.
• This microstructure consists of a microporosity formed by the stack of sand-lime needles (porous distribution of the material in this case), formed mainly of xonotlite and / or tobermorite and / or other types of CSH-type phases. (foshagitis, Riversideite ). It is understood by CHS the lime / water / silica ratio. The vacant space between the needles thus forms an open porosity which can vary from 60 to 95%.
• Such a microstructure is described in particular in documents EP 1 887 275 and EP 1 886 982.
• the significant loss of pressure is due to the very small size of the pores (between 0.1 ⁇ m and 1 ⁇ m) and their very narrow volume distribution (of almost monomodal type). It is understood by pore size the average stack generated by the needles mainly xonotlite.
• a solution of the invention is a ceramic porous material comprising:
• a microstructure comprising a material of crystalline structure xonotlite and / or tobermorite crystallized in the form of needles bonded to each other so as to form between them a pore diameter D95 greater than or equal to 0.4 ⁇ m and less than 5 ⁇ m and an average pore diameter D50 greater than or equal to 0.4 ⁇ m and less than 1.5 ⁇ m; preferentially from 0.4 to 1 ⁇ m; and
• a macrostructure consisting of a continuous stack and / or discontinuous macro pores.
• macro pores with a diameter of between 10 and 2,000 ⁇ m. These macro pores can be spherical, oval, sticks, ...
• microstructure is meant the microscopic structure of the material.
• Macro structure means the architecture of matter.
• this architecture in the form of macropores interconnected or not allows the formation of preferential paths continuous or discontinuous for the diffusion of fluids within the microstructure.
• Figure 1 shows on the left the current single needle microstructure of a ceramic porous mass for the storage of gas and / or liquid and on the right the combination microstructure - macro structure (here we are dealing with shaped pore stacks). "Sticks").
• pore diameter D95 is meant a diameter at which 95% by volume of the pore diameter less than 5 microns.
• pore diameter D 50 is meant a diameter at which 50% by volume of the pore diameter is less than 1.5 ⁇ m.
• Xonotlite is a calcium silicate of formula CaOSi 6 On (OH) 2 , which has repeating units consisting of three tetrahedra.
• tobermorite is also a calcium silicate, of formula Ca 5 Si 6 (O, OH) is.5H 2 O, crystallized in orthorhombic form.
• All the intermediate phases preferably represent from 0 to 10% and more preferably from 0 to 5% of the weight of the crystalline phase present in the porous material.
• the calcium carbonate and the silica each preferably represent less than 3% of the total weight of these final crystalline phases.
• porous material in the form of a stack of needles entangled with each other allows the structure to have the qualities required to stabilize the solvent in which the gas and / or the liquid is dissolved and to limit its decomposition. confining it in an infinite number of microscopic spaces, thus ensuring the safety of the containers and their regulatory compliance with normative tests, such as ISO 3807-1.
• the interconnected macro-pores or not have a mean diameter greater than 10 microns.
• the macro porosity of the ceramic porous mass will be the consequence of the stacking of the porogens, and the continuity or not of the network will be the consequence of the interconnection of so-called pore-forming, this interconnection being a function of the volume content and the shape of the said blowing.
• the advantage of this technique is that it is possible to vary the macro structure of the porous mass as a function of the porogen (or of the mixture of porogens) used during manufacture, namely its rate in the starting block (formulation) and its / its geometric shapes.
• the shape and dimensions of the pores are directly related to the initial pore-forming agents. It is understood by initial pore-forming agent a natural carbon compound (starch, potato starch, etc.) or not (PMMA, polystyrene, etc.). Continuous stacking and / or batch is a function of the initial rate of porogen (s) in the starting formulation. It is commonly understood that if the content is less than 35% by volume with respect to solids volumes the interconnection will be discontinuous majority. Beyond this value the macro structure will be considered continuous.
• the porous material may have one or more of the following characteristics:
• the macro-structure is constituted by macro-pores with a diameter of between 10 ⁇ m and 10 mm, preferably between 10 ⁇ m and 2 mm;
• the macro-pores have a geometric shape chosen from spheres, platelets, cylinders, cubes or a combination of these forms;
• said needles have a length ranging from 2 to 10 ⁇ m, preferably from 2 to 5 ⁇ m, a width ranging from 0.010 to 0.25 ⁇ m and a thickness of less than 0.25 ⁇ m;
• the material contains at least 70% by weight of crystalline phase, preferably at least 90%.
• the porous material may also comprise fibers selected from synthetic carbon-based fibers, as described in particular in US-A-3,454,362, alkaline-resistant glass fibers, as described in particular in the document EP-A-262031, and mixtures thereof, without this list being limiting.
• These fibers are useful in particular as reinforcing materials, to improve the impact resistance of the porous material, and also make it possible to avoid the problems of cracking during drying of the structure.
• These fibers can be used as is or after treatment of their surface.
• the porous ceramic material may furthermore in its production process (formulation of the paste) include dispersing agents or binders, such as cellulose derivatives, in particular carboxymethylcellulose, hydroxypropylcellulose or ethylhydroxyethylcellulose, polyethers, such as polyethylene glycol, synthetic clays of smectite type, amorphous silica of specific surface area advantageously between 150 and 300 m 2 / g, and mixtures thereof, without this list being limiting.
• dispersing agents or binders such as cellulose derivatives, in particular carboxymethylcellulose, hydroxypropylcellulose or ethylhydroxyethylcellulose, polyethers, such as polyethylene glycol, synthetic clays of smectite type, amorphous silica of specific surface area advantageously between 150 and 300 m 2 / g, and mixtures thereof, without this list being limiting.
• the porous ceramic material may furthermore also contain initial silico-calcareous compounds, such as wolastonite (CaSiOs) for example, as nucleating agent (s) (Seeding operation) allowing a faster germination of the tobermorite and / or xonotlite crystals.
• initial silico-calcareous compounds such as wolastonite (CaSiOs) for example, as nucleating agent (s) (Seeding operation) allowing a faster germination of the tobermorite and / or xonotlite crystals.
• nucleating agent Seeding operation
• the content of nucleating agent ranges from 0.1 to 5% by weight relative to all the solid precursors.
• the ceramic porous material may further contain phosphoric acid in its production process (formulation of the mash) ( ⁇ 1% of the total volume of the mash containing the lime, silica and water).
• the porous material contains fibers, in particular carbon and / or glass and / or cellulose fibers.
• the amount of the fibers is advantageously less than 55% by weight, relative to all the solid precursors used in the process for manufacturing the porous material. It is preferably between 3 and 20% by weight.
• the porous material according to the invention preferably has a compressive strength greater than or equal to 15 kg / cm 2 , ie 1.5 MPa, more preferably greater than 25 kg / m 2 , ie 2.5 MPa.
• the mechanical compressive strength can be measured by taking a cube of 100 x 100 mm 2 from the porous material and applying a pressure force on the upper surface thereof while it is held against a horizontal metal plate. This force corresponds to the pressure from which the material begins to crack.
• the present invention relates to a method of manufacturing the porous material according to the invention, comprising the following steps:
• This mixture may also contain glass fibers, organic compounds, nucleating agents and phosphoric acid,
• step b) a step of introducing, into the mixture prepared in step a), a mixture of at least one pore-forming agent that can be thermally decomposed at temperatures between
• step c) a step of hydrothermal synthesis of the porous material around the stack of porogenic agents of step b), starting from the mixture resulting from step a) and comprising the porogens of step b), d) a step of drying the porous material resulting from step c), and
• FIG. 2 illustrates the different steps of the manufacturing method according to the invention.
• this method may comprise other steps than those mentioned above, which may be preliminary, intermediate or additional steps thereto.
• the manufacturing method according to the invention may have one or more of the following characteristics:
• porogens are polymeric
• the porogens are based on PVC, polymethyl methacrylate, polystyrene, polyurethane, polyethylene, vegetable fibers (starch, potato starch, coconut, etc.), carbon or a mixture of these elements. Indeed, the nature of the porogens must be based on polymer, carbon or natural.
• the porogens can be of different forms: beads, fibers, nodules, platelets.
• the size of the porogen will be chosen according to the macroporosity that one wishes to obtain. In general, it will be between 10 ⁇ m and 2 mm.
• the second step (step b)) consists in introducing a mixture of porogenic agent (s) carbon (s) preferentially polymeric and / or natural in the starting mixture comprising precursors silico-limestone (lime and silica).
• Porogenic agent is understood to mean a set of small shaped elements (spherical, fiber or other) and of controlled size. It is the stacking of a multitude of these elements that forms a macro structure that will be used as a negative to obtain a macroporosity.
• step c) is carried out, which consists in subjecting the lime-silica mixture of step a) in which the porogens have been introduced to a hydrothermal synthesis at a temperature between 170 ° C. and 300 ° C., preferably between 180 and 220 ° C., for a duration ranging from 10 h to 70 h, depending on the volume of the container to be lined, for example close to 40 h for a container with a volume in water equal to 6 liters.
• the fourth step of the process (step d)) or drying step serves not only to evacuate the residual water, but also to give the treated mass a predominantly crystalline structure. This operation is carried out in a traditional electric oven or gas (the same or not that used for the hydrothermal synthesis operation), at atmospheric pressure.
• the fifth step of the process (step e)) consists in extracting the porogens by combustion.
• the extraction leads to the formation of pores facilitating the diffusion of liquid or gaseous fluids within the microstructure.
• a temperature is applied to the porous material that burns the porogenic carbonaceous elements. This temperature must remain below 600 0 C to avoid destroying the initial microstructure.
• This step can be coupled with the drying step.
• a continuous and / or discontinuous stack corresponding to the shape of the initial pore-forming agents is obtained within the ceramic porous material.
• a macro porosity coupled according to the invention to a microporosity, formed by a double porosity (micro and macro-pores).
• Figure 3 comprises on the left an overview of the porous material according to the invention and on the right a zoomed view of the same porous material.
• This figure shows the macrostructure formed by interconnected macro pores. These macro-pores are between 0.1 and 0.2 mm in size.
• Figure 4 shows 4 photographs showing more precisely the interconnected macro pores. The photographs were taken by electron microscopy on a FESEM Zeiss ultra 55.
• Figure 4 shows on the left two photographs (a global view and a zoomed view) showing the porous material according to the state of the art, that is to say without interconnected macropores, and on the right two photographs (a global view and a zoomed view) showing the porous material according to the invention, that is to say with interconnected macro pores.
• the invention also relates to a container containing a porous material as described above, which container is adapted to contain and distribute a fluid.
• the container may be thermally insulated at its outer wall and able to contain and dispense a cryogenic fluid.
• the container usually comprises a metal shell enclosing the porous material described above.
• the metal casing may consist of a metallic material such as steel, for example a standard carbon steel P265NB according to the NF EN10120 standard, the thickness of which makes it capable of withstanding at least the test pressure of 60 bar (6 MPa), normative value for the regulation of acetylene under the conditions described above.
• the container is also usually cylindrical and generally provided with closure means and a pressure regulator. This container preferably has a diameter / length ratio of between 0.2 and 0.7, more preferably between 0.35 and 0.5, and a minimum water capacity of one liter. Usually, such a container will be in the shape of a bottle.
• the fluids stored in the packing structure according to the invention may be gases or liquids.
• gas there may be mentioned pure compressed gases or mixtures in gaseous or liquid form, such as hydrogen, gaseous hydrocarbons (alkanes, alkynes, alkenes), nitrogen and acetylene, and gases dissolved in a gas.
• solvents such as acetylene and acetylene-ethylene or acetylene-ethylene-propylene mixtures dissolved in a solvent such as acetone or dimethylformamide (DMF).
• organometallic precursors such as Ga and In precursors, used in particular in electronics, as well as nitroglycerine. All the alcohols or mixtures of alcohol can also be mentioned.
• the container according to the invention contains acetylene dissolved in
• the container may alternatively be thermally insulated at its outer wall and able to contain and dispense a cryogenic fluid such as: hydrogen, helium, oxygen, nitrogen or any other liquid gas.
• a cryogenic fluid such as: hydrogen, helium, oxygen, nitrogen or any other liquid gas.
• the ceramic porous material according to the invention with a controlled macroporosity makes it possible to reduce these negative effects while maintaining a satisfactory safety factor.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Analytical Chemistry (AREA)
• Ceramic Engineering (AREA)
• Mechanical Engineering (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Inorganic Chemistry (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Nanotechnology (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Porous Artificial Stone Or Porous Ceramic Products (AREA)
• Catalysts (AREA)

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• 2009
  • 2009-08-05 FR FR0955510A patent/FR2948884B1/fr not_active Expired - Fee Related
• 2010
  • 2010-07-19 RU RU2012108078/03A patent/RU2012108078A/ru unknown
  • 2010-07-19 CN CN201080034581.0A patent/CN102471158A/zh active Pending
  • 2010-07-19 MX MX2012001499A patent/MX2012001499A/es unknown
  • 2010-07-19 CA CA2767774A patent/CA2767774A1/fr not_active Abandoned
  • 2010-07-19 WO PCT/FR2010/051506 patent/WO2011015751A1/fr not_active Ceased
  • 2010-07-19 BR BR112012007894A patent/BR112012007894A2/pt not_active Application Discontinuation
  • 2010-07-19 EP EP10752037A patent/EP2462077A1/fr not_active Withdrawn
  • 2010-07-19 IN IN925DEN2012 patent/IN2012DN00925A/en unknown

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