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
  • C04B28/02—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 hydraulic cements other than calcium sulfates
• • 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
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/02—Granular materials, e.g. microballoons
  • C04B14/04—Silica-rich materials; Silicates
• • 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
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/02—Granular materials, e.g. microballoons
  • C04B14/04—Silica-rich materials; Silicates
  • C04B14/06—Quartz; Sand
• • 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
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/02—Granular materials, e.g. microballoons
  • C04B14/26—Carbonates
  • C04B14/28—Carbonates of calcium
• • 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
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/38—Fibrous materials; Whiskers
• • 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
  • C04B2111/00034—Physico-chemical characteristics of the mixtures
  • C04B2111/00103—Self-compacting mixtures
• • 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
  • C04B2111/60—Flooring materials
  • C04B2111/62—Self-levelling compositions
• • 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
  • C04B2111/80—Optical properties, e.g. transparency or reflexibility
  • C04B2111/802—White cement
• • 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
  • C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
  • C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
  • C04B2201/52—High compression strength concretes, i.e. with a compression strength higher than about 55 N/mm2, e.g. reactive powder concrete [RPC]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P40/00—Technologies relating to the processing of minerals
  • Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/91—Use of waste materials as fillers for mortars or concrete

Definitions

• the subject of the present invention is an ultra high performance, self-compacting concrete which is not heat treated as well as the process for the preparation and the uses of this concrete.
• concrete means a body of cement matrix which can, according to the works to be carried out, include fibers, and being obtained by hardening of a cement composition mixed with water.
• ultra high performance concrete is understood to mean a concrete having a characteristic compressive strength at 28 days equal to or greater than 150 MPa, this value being given for a concrete stored and maintained at 20 ° C., which n has not undergone any cure or heat treatment.
• self-placing concrete is understood to mean a very fluid homogeneous and stable concrete, which is implemented without vibration.
• Very high performance concretes are known to those skilled in the art.
• European patent application EP 0 934 915 A1 describes a very high performance and self-leveling concrete, containing in particular cement, a mixture of calcined bauxite sands of different particle sizes, silica smoke, adjuvants such as an agent anti-foam and a water-reducing superplasticizing agent, possibly fibers and water.
• Such concretes have high mechanical properties, in particular a characteristic compressive resistance to
• the Applicant has succeeded in developing an ultra high performance concrete with a light shade by replacing the silica smoke with ultrafine particles of calcium carbonate having a specific surface of at least 10 m 2 / g and an IF form index of at least minus 0.3, preferably 0.4.
• shape index IF of a set of particles is meant, within the meaning of the present invention, the ratio of the sum of the thicknesses ⁇ E of the particles (E being the thickness of a particle) over the sum of the lengths ⁇ L of these same particles (L being the length of a particle), in a sample of several hundred particles.
• the shape coefficient will be determined from the observation of the particles and the measurement of their dimensions using a field effect scanning electron microscope (SEM).
• SEM field effect scanning electron microscope
• the procedure is as follows: - sampling from a batch of ultrafine particles of calcium carbonate of samples comprising approximately one hundred particles each, - preparation of the samples for observation by SEM by metallization of the particles then fixation of the metallized particles with the sample holder, - observation by SEM of the samples, - measurement of the smallest and the largest dimension of each grain using the stage, the smallest dimension constituting the thickness E of the particle , and the largest dimension constituting the length L of this particle, and calculation of the shape index IF for each sample, - calculation of the average of the shape index over all the examined samples.
• the shape index IF of a set of spherical particles is equal to 1, and that of a set of cubic particles is approximately of the order of 0.58.
• the average "diameter" of a grain denotes the diameter of the smallest sphere in which said grain can be included.
• the present invention therefore relates to an ultra high performance and self-consolidating concrete comprising: - a cement, - a mixture of calcined bauxite sands of different particle sizes, the finest sand having an average particle size of less than 1 mm and the most sand coarse with an average particle size of less than 10 mm, - silica smoke, 90% of the particles of which have a diameter of less than 1 ⁇ m, the average diameter being approximately 0.5 ⁇ m, - an anti-foaming agent, - a water reducing superplasticizer, - possibly fibers, and - water, characterized in that the silica smoke represents at most 15 parts by weight relative to 100 parts by weight of cement, in that it also comprises ultrafine particles of calcium carbonate having a specific surface equal to or greater than 10m 2 / g, preferably equal to or greater than 15 m / g, and better still of the order of 20 m / g, as well as an IF form index equal to or greater than
• the degree of clarity of the concrete according to the invention is a function of the proportion of ultrafine particles of calcium carbonate m compared to silica smoke in concrete.
• the ratio, by weight, of the amount of ultrafine particles of calcium carbonate in concrete to the amount of silica fume can vary from 1: 99 to 99: 1, and preferably from 50: 50 to 99: 1. If if you want an ultra high performance concrete with a very clear, even almost white color, it is possible to completely replace the silica smoke with the ultrafine particles of calcium carbonate.
• the invention therefore also relates to an ultra high performance and self-consolidating concrete, in which the silica smoke has been completely replaced by ultrafine particles of calcium carbonate.
• Such concrete comprises: - a cement, - a mixture of calcined bauxite sands of different particle sizes, the finest sand having an average particle size less than 1 mm and the coarser sand having an average particle size less than 10 mm, - ultrafine particles of calcium carbonate, having a specific surface equal to or greater than 10 m 2 / g, preferably equal to or greater than 15 m 2 / g, and better still of the order of 20 m 2 / g, as well as an IF form index equal to or greater than 0.3, preferably equal to or greater than 0.4, - an anti-foaming agent, - a water-reducing superplasticizer, - optionally fibers, - and water, cements, sands, ultrafine particles of calcium carbonate having a particle size distribution such that there are at least three and at most five classes different particle sizes, the ratio between the average diameter of a particle size class and that of the immediately higher class being approximately 10.
• ultrafine particles of calcium carbonate preference is given to ultrafine particles of calcium carbonate crystallized in the form of small cubes. This shape contributes to making the concrete very fluid in the fresh state, these particles of calcium carbonate being able to be inserted easily between the grains of cement and the grains of sand.
• the cement used in the present invention is preferably a white cement. It can be chosen from Portland type CEM 1 cements, having additional characteristics such as "Sea setting-PM” or even better “Sea setting and resistant to sulfates-PM-ES” or their mixtures.
• white cement is meant within the meaning of the present invention an essentially white-colored cement, the composition of which comprises very pure raw materials such as limestone and kaolin, and which is essentially free of all traces of oxide of iron.
• white cement usable in the concrete of the invention mention may be made of the white cement CPA 52.5 from Section marketed by LAFARGE.
• mixture of calcined bauxite sands is meant, within the meaning of the present invention, not only a mixture of calcined bauxite sands of different particle sizes, but also a mixture comprising calcined bauxite sand with aggregates having very large resistance and hardness such as, in particular, aggregates of corundum, emery or metallurgical residues such as silicon carbide, or else with another type of sand, and preferably calcareous sand because it has a clear hue.
• a mixture of two or three calcined bauxite sands of different particle sizes is preferably used.
• this mixture of sands consists of: - a sand of average particle size less than 1 mm comprising 20% of aggregates of dimension less than 80 microns, - a sand of particle size between 3 and 7 mm, and - optionally a sand with a particle size between 1 and 3 mm.
• the sand of smaller particle size can be replaced in whole or in part by: - cement, mineral additions such as ground slag, fly ash or even calcined bauxite filler whose average diameter is close to that of cement, for which is the fraction of 20% of aggregates of dimension less than 80 ⁇ m, and - sand with a particle size greater than 1 mm (for example 3 to 7 mm) with regard to the other fraction.
• the concrete according to the invention comprises silica smoke (in mixture with ultrafine particles of calcium carbonate)
• the silica smoke can be densified or non-densified, that is to say that it has a density comprised between 200 and 600 kg / m3.
• This silica smoke must contain, once dispersed in the concrete, at least 40% of particles of dimension less than one micron, the dimension of the remaining particles being less than 20 ⁇ m.
• an anti-foaming agent conventionally used for oil drilling is used, that is to say in applications requiring very precise adjustment of the density of the cast material.
• defoamers are called "defoamer and deaerator admixtures”. These agents are available in dry or liquid form.
• anti-foaming agents which can be used in the concrete according to the invention, mention may in particular be made of mixtures of dodecyl alcohol and polypropylene glycol, dibulylphthalates, dibutylphosphates, silicone polymers such as polydimethylsiloxane, and modified silicates.
• a silicate agent treated with a polymerized glycol sold by the company TROY CHEMICAL CORPORATION under the brand TROYKYD® D126 is used as anti-foaming agent.
• water-reducing superplasticizer use is preferably made of a water-reducing superplasticizer of the modified polycarboxylic ether type, such as GLENIUM® 51 sold by the company MBT France, or a water-reducing superplasticizer of the synthetic acrylic vinyl copolymer type. such as the superplasticizer NISCOCRETE 5400F sold by the company SIKA France, or even a water reducing superplasticizer in the form of an aqueous solution of modified polycarboxylates such as NISCOCRETE 20HE, also sold by the company SIKA France.
• fibers are incorporated into the concrete. These fibers can be synthetic organic, mineral or metallic. They can in particular be chosen from among the fibers made of homopolymer or copolymer of polyethylene, polypropylene, polyamide, polyvinyl alcohol, carbon fibers, Kevlar®, and steel fibers. These fibers can have any shape. However, in order to obtain good workability of the concrete, it is preferred to use straight fibers. These fibers have a diameter between 0.1 and 1.0 mm, preferably between 0.2 and
• the granular matrix is modified. Indeed, the fibers having to be taken up, it is therefore necessary that the quantity of fines, that is to say particles of dimension less than 0.1 mm, increases.
• the quantity of ultrafine particles of calcium carbonate, and where appropriate of fumes of silica, cement, sand of smaller particle size and / or mineral additions is therefore greater than that of a concrete without fibers.
• the concrete comprises, in parts by weight: - 100 of cement, - 50 to 200 of mixtures of calcined bauxite sands, of different particle sizes, the finest sand having a average particle size less than 1 mm, and the coarsest sand having an average particle size less than 10 mm; - 5 to 25 of ultrafine particles of calcium carbonate and silica smoke, the silica smoke representing at most 15 parts by weight; - 0.1 to 10 anti-foaming agent; - 0.1 to 10 of water reducing superplasticizer; - 15 to 24 fibers; and - 10 to 30 of water.
• the ratio, by weight, of the quantity of ultrafine particles of calcium carbonate in the concrete to the quantity of silica smoke which can vary from 1: 99 to 99: 1, and preferably from 50: 50 to 99: 1. If it is desired to obtain a concrete of light shade, while retaining a characteristic compressive strength at 28 days high, the best results are obtained with a concrete according to the invention completely free of silica smoke, which comprises, in parts in weight: - 100 of cement, - 80 to 150, preferably 100 to 125, of mixtures of calcined bauxite sands, of different particle sizes, the finest sand having an average particle size less than 1 mm, and the coarsest sand having an average particle size less than 10 mm ; - 10 to 20, preferably 13 to 17 of ultrafine particles of calcium carbonate; - 0.2 to 5, preferably 0.5 to 0.7, anti-foaming agent; - 5 to 7 of water reducing superplasticizer; - 17 to 20 fibers; and - 10 to 20, preferably
• the concrete composition according to the invention from 0.5 to 3 parts, preferably from 0.5 to 2 parts, and more preferably still 1 part of calcium oxide or of calcium sulphate.
• Calcium oxide or calcium sulphate is added in powder or micronized form and must make it possible to compensate for the endogenous shrinkage inherent in formulations based on hydraulic binders associated with very small quantities of water.
• the quantities of the various constituents of the concrete can be adjusted by a person skilled in the art depending on the use and the desired properties of the concrete. The higher the proportion of ultrafine particles of calcium carbonate in the concrete compared to the silica smoke, the lighter the color of this concrete. Thus, in the case of a complete substitution of the silica smoke by the ultrafine particles of limestone, and the use of a white cement, one then obtains a concrete of almost white tint.
• the invention also relates to a process for the preparation of concrete. According to a first embodiment of the invention, all the constituents of the concrete according to the invention are introduced into a kneader, kneading and a concrete ready for molding or pouring is obtained which has very good workability.
• all the dry granular materials are mixed first, that is to say the cement, the sands, the calcareous ultrafine particles and, where appropriate, the silica smoke, and optionally the superplasticizer and the anti-foaming agent then, this premix is added to a mixer to which water, the superplasticizer and the anti-foaming agent are added, if these are in liquid form, and the fibers if necessary.
• the mixture of powders is first prepared, then, at the time of use, the powders are kneaded with the desired quantities of fibers and of water, optionally of water-reducing superplasticizer, and of anti-foaming agent insofar as these are in liquid form.
• bags or other types of packaging (for example "big bags") of dry premixed product ready for use are prepared, which are easy to keep and store since they have a very high low water content.
• a mixer with the desired amounts of fiber and water, and possibly of water-reducing supe ⁇ lasticizer.
• the concrete according to the invention obtained can be molded without difficulty, given its very high spreading performance.
• the concrete according to the invention has no need to undergo a heat treatment to achieve the required performance. Of course, a heat treatment could be envisaged to further improve the performance, but this would entail an additional cost.
• the present invention also relates to ready-to-use dry premixed products.
• the concrete according to the invention can be used in all fields of application of reinforced concrete or not. More particularly, taking into account the fact that this concrete is self-compacting, it can be poured in place for the production of posts, beams, beams, floors, etc. It can also be used in all prefabrication applications. Given its characteristics of cohesion and viscosity, it can be used for formwork comprising inserts. It can also be used to create keyways between structural elements.
• the concrete according to the invention can also be used for the production of pavements, civil engineering structures, prestressed parts or composite materials. Furthermore, its high compressive strength allows a reduction in the dimensioning of structures implementing it.
• the concrete according to the invention would be particularly useful for example for all the elements, drums, tubes, containers, used for sanitation. It also has a very low coefficient of friction which is not modified over time, which makes it entirely suitable for transporting materials conventionally corrosive to concrete.
• the concretes according to the invention having a reduced or even zero content of silica fume can be used in all architectural applications, because of their clear color which is particularly sought after for such applications, and their good mechanical properties, especially high compressive strength.
• the present invention will be explained in more detail using the following single example, which is not limiting. The quantities are given in parts by weight unless otherwise indicated.
• Raw materials - the cement used is a white CPA 52.5 white Section cement marketed by Lafarge;
• the mixture of bauxite sands used is a mixture of a bauxite sand with a particle size less than 1 mm, and a bauxite sand with a particle size between 3 and 7 mm;
• the ultrafine calcium carbonate particles are ultrafine additions of synthetic calcium carbonate crystallized in the form of cubes and marketed by SOLNAY under the brand SOCAL® 31;
• the fibers used are straight steel fibers, 0.3 mm in diameter and 20 mm in length;
• the water reducing superplasticizer is marketed by the SIKA France company under the trade name NISCOCRETE 5400 F;
• the anti-foaming agent used is an anti-foaming agent sold by the company

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• Civil Engineering (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Preparation Of Clay, And Manufacture Of Mixtures Containing Clay Or Cement (AREA)

Priority Applications (10)

Applications Claiming Priority (2)

Publications (2)

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Cited By (17)

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• 2004
  • 2004-02-13 FR FR0401492A patent/FR2866330B1/fr not_active Expired - Lifetime
• 2005
  • 2005-02-11 EP EP05717623.2A patent/EP1713740B1/fr not_active Expired - Lifetime
  • 2005-02-11 CN CN2005800086482A patent/CN1934052B/zh not_active Expired - Fee Related
  • 2005-02-11 US US10/589,138 patent/US7641731B2/en active Active
  • 2005-02-11 RU RU2006132737A patent/RU2359936C2/ru not_active IP Right Cessation
  • 2005-02-11 ES ES05717623.2T patent/ES2630184T3/es not_active Expired - Lifetime
  • 2005-02-11 AU AU2005212878A patent/AU2005212878B2/en not_active Ceased
  • 2005-02-11 CA CA 2555590 patent/CA2555590C/fr not_active Expired - Fee Related
  • 2005-02-11 PT PT57176232T patent/PT1713740T/pt unknown
  • 2005-02-11 JP JP2006552669A patent/JP5106860B2/ja not_active Expired - Fee Related
  • 2005-02-11 ZA ZA200607632A patent/ZA200607632B/xx unknown
  • 2005-02-11 BR BRPI0507638-2A patent/BRPI0507638B1/pt not_active IP Right Cessation
  • 2005-02-11 KR KR20067018343A patent/KR101204872B1/ko not_active Expired - Fee Related
  • 2005-02-11 WO PCT/FR2005/000334 patent/WO2005077857A2/fr not_active Ceased
• 2006
  • 2006-08-07 MA MA29245A patent/MA28349A1/fr unknown
  • 2006-08-14 IN IN4680DE2006 patent/IN2006DE04680A/en unknown
  • 2006-09-13 NO NO20064135A patent/NO342641B1/no not_active IP Right Cessation

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