MD998Z - Method for the production of building decoration material - Google Patents

Method for the production of building decoration material Download PDF

Info

Publication number
MD998Z
MD998Z MDS20150077A MDS20150077A MD998Z MD 998 Z MD998 Z MD 998Z MD S20150077 A MDS20150077 A MD S20150077A MD S20150077 A MDS20150077 A MD S20150077A MD 998 Z MD998 Z MD 998Z
Authority
MD
Moldova
Prior art keywords
temperature
finishing
well
simultaneous
building
Prior art date
Application number
MDS20150077A
Other languages
Romanian (ro)
Russian (ru)
Inventor
Александр КОТЛЯРОВ
Original Assignee
Александр КОТЛЯРОВ
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Александр КОТЛЯРОВ filed Critical Александр КОТЛЯРОВ
Priority to MDS20150077A priority Critical patent/MD998Z/en
Priority to PCT/MD2016/000001 priority patent/WO2016200247A1/en
Publication of MD998Y publication Critical patent/MD998Y/en
Publication of MD998Z publication Critical patent/MD998Z/en
Priority to IL252180A priority patent/IL252180A/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02Compositions 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
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/02Selection of the hardening environment
    • C04B40/0204Selection of the hardening environment making use of electric or wave energy or particle radiation
    • C04B40/0213Electromagnetic waves
    • C04B40/0218Microwaves
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/50Flexible or elastic materials
    • C04B2111/506Bendable material

Landscapes

  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Toxicology (AREA)
  • Health & Medical Sciences (AREA)
  • Electromagnetism (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Finishing Walls (AREA)

Abstract

The invention relates to building materials, particularly to processes for producing building finishing materials, and can be used for interior and exterior finishing of all surfaces of the residential, industrial and other buildings, as well as fireplaces, furnaces, ceilings, bathrooms, etc.The process for producing a building finishing material comprises mixing of the inorganic binder and/or auxiliary agents with quartz sand with the production of a homogeneous material, formation of the material with its simultaneous reinforcement by a cushioning material, and thermal treatment. The thermal treatment is carried out over the entire volume of the material with the help of a microwave oscillator, at a frequency of 2450 MHz, for 20…40 s, at a temperature of 20…180°C, with simultaneous vacuum evaporation of the air, as well as with subsequent curing of the produced material at a temperature of 25…38°C for 20…40 min.

Description

Invenţia se referă la materiale de construcţie, în special la procedee de fabricare a materialelor de construcţie de finisare, şi poate fi utilizată pentru finisajul interior şi exterior al tuturor suprafeţelor clădirilor de locuit, industriale şi altor clădiri, precum şi ale căminelor, cuptoarelor, tavanelor, camerelor de baie etc. The invention relates to building materials, in particular to processes for manufacturing finishing building materials, and can be used for interior and exterior finishing of all surfaces of residential, industrial and other buildings, as well as fireplaces, ovens, ceilings, bathrooms, etc.

Utilizarea materialelor de finisare naturale necesită un volum mare de muncă şi este costisitoare, deci a apărut necesitatea de a înlocui piatra şi lemnul cu un material greu de deosebit de cel natural, dar care este uşor de instalat, ieftin, durabil, ecologic pur, uşor şi, în plus, un bun izolator termic. The use of natural finishing materials requires a large amount of work and is expensive, so the need arose to replace stone and wood with a material that is difficult to distinguish from natural ones, but which is easy to install, inexpensive, durable, ecologically pure, lightweight and, in addition, a good thermal insulator.

Este cunoscut un procedeu de producere a unui material de construcţie de finisare sau a unui articol de construcţie din gresie silicioasă, care constă în combinarea liantului cu gresia, formarea şi uscarea acestora până la solidificare cu formarea unui material de construcţie de finisare sau a unui articol de construcţie. În procedeul cunoscut liantul se combină cu gresia direct în locurile de formare naturală a acestuia prin impregnarea stratului superficial al stratului geologic de gresie, totodată înainte de impregnare stratul superficial menţionat se nivelează, apoi stratul superficial impregnat se usucă în condiţii climatice naturale până la formarea stratului solidificat. Iar materialul de construcţie de finisare sau articolul de construcţie se formează prin tăierea stratului solidificat menţionat până la forma şi dimensiunea dorită şi desprinderea de la suprafaţa stratului de gresie [1]. A process for producing a finishing building material or a construction article made of siliceous sandstone is known, which consists in combining the binder with the sandstone, forming and drying them until solidification with the formation of a finishing building material or a construction article. In the known process, the binder is combined with the sandstone directly in the places of its natural formation by impregnating the surface layer of the geological sandstone layer, at the same time before impregnation the said surface layer is leveled, then the impregnated surface layer is dried under natural climatic conditions until the solidified layer is formed. And the finishing building material or the construction article is formed by cutting the said solidified layer to the desired shape and size and detaching it from the surface of the sandstone layer [1].

Dezavantajul acestui procedeu constă în aceea că materialul este foarte fragil, la căptuşeala exterioară materialul necesită acoperire regulată cu lac hidrofob, ceea ce limitează în mare măsură aplicarea acestuia. The disadvantage of this process is that the material is very fragile; the outer lining requires regular coating with hydrophobic varnish, which greatly limits its application.

Cea mai apropiată soluţie este procedeul de obţinere a acoperirii vizibile, care include amestecarea agentului de stabilizare slab, apei, argilei, metilcelulozei, polizaharidelor, alcoolului polivinilic, cazeinei, argilei nisipoase, saponitului, argilei chineze, oxidului de zinc şi/sau sticlei solubile, sau a oricărei combinaţii a acestora, cu materialul granulat. Totodată materialul granulat este selectat dintre piatra naturală, de preferinţă cuarţ, nisipul de cuarţ, gresie, granit, şist, marmură, tuf, sticlă, plastic, lemn şi/sau metal, sau orice combinaţie a acestora [2]. The closest solution is the visible coating process, which includes mixing the weak stabilizing agent, water, clay, methylcellulose, polysaccharides, polyvinyl alcohol, casein, sandy clay, saponite, china clay, zinc oxide and/or soluble glass, or any combination thereof, with the granulated material. At the same time, the granulated material is selected from natural stone, preferably quartz, quartz sand, sandstone, granite, shale, marble, tuff, glass, plastic, wood and/or metal, or any combination thereof [2].

Dezavantajul procedeului cunoscut constă în elasticitatea scăzută a materialului obţinut, care la curbarea la 80° şi mai mult crapă de-a lungul liniei curburii, deci durabilitatea materialului este redusă. The disadvantage of the known process lies in the low elasticity of the obtained material, which when bent at 80° and more cracks along the line of curvature, so the durability of the material is reduced.

Problema pe care o rezolvă prezenta invenţie constă în îmbunătăţirea calităţii materialului de finisare din contul creşterii rezistenţei, sporirea elasticităţii acestuia, ameliorarea proprietăţilor termoizolante, precum şi reducerea costului de producţie a materialului. The problem solved by the present invention consists in improving the quality of the finishing material by increasing its resistance, increasing its elasticity, improving its thermal insulation properties, as well as reducing the production cost of the material.

Problema se soluţionează prin aceea că procedeul de fabricare a materialului de construcţie de finisare include amestecarea liantului anorganic şi/sau mijloacelor auxiliare cu nisip cuarţos cu obţinerea unui material omogen, formarea materialului cu armarea lui concomitentă printr-un material intermediar, şi tratamentul termic. Totodată tratamentul termic se efectuează pe întregul volum al materialului cu ajutorul unui generator de frecvenţă foarte înaltă, la o frecvenţă de 2450 MHz, timp de 20…40 s, la o temperatură de 20…180°C, cu evaporarea simultană a aerului prin vidare, precum şi cu menţinerea ulterioară a materialului obţinut la o temperatură de 25…38°C timp de 20…40 min. The problem is solved by the fact that the process of manufacturing the finishing building material includes mixing the inorganic binder and/or auxiliary means with quartz sand to obtain a homogeneous material, forming the material with its simultaneous reinforcement by an intermediate material, and heat treatment. At the same time, the heat treatment is carried out on the entire volume of the material using a very high frequency generator, at a frequency of 2450 MHz, for 20…40 s, at a temperature of 20…180°C, with simultaneous evaporation of air by vacuum, as well as with subsequent maintenance of the obtained material at a temperature of 25…38°C for 20…40 min.

Rezultatul tehnic constă în sporirea rezistenţei şi elasticităţii materialului. The technical result consists in increasing the resistance and elasticity of the material.

Datorită tratamentului termic se modifică structura straturilor din care constă materialul, şi la limitele acestor straturi creşte elasticitatea materialului, ceea ce permite de a obţine un material de finisare, care poate fi îndoit în mod repetat la 180° fără deformare exterioară şi interioară şi formarea fisurilor. În plus, materialul este energoeconom cu coeficientul de conductibilitate termică λ = 0,137 W/mK, la un cost de producţie redus, materialul este ecologic pur şi fabricarea materialului solicitat de asemenea este ecologic pură. Due to the heat treatment, the structure of the layers of which the material consists changes, and at the boundaries of these layers the elasticity of the material increases, which allows to obtain a finishing material, which can be repeatedly bent by 180° without external and internal deformation and the formation of cracks. In addition, the material is energy-efficient with a thermal conductivity coefficient of λ = 0.137 W/mK, at a low production cost, the material is ecologically pure and the manufacture of the requested material is also ecologically pure.

Materialul de construcţie de finisare, obţinut prin procedeul propus, poate fi uşor lipit pe o suprafaţă de orice configuraţie, nu se deformează, nu crapă şi este uşor de tăiat la dimensiunile necesare, ceea ce reduce esenţial costurile de montare şi timpul de montare în sine, iar în aparenţă nu se deosebeşte de piatra naturală sau lemn. The finishing construction material, obtained by the proposed process, can be easily glued to a surface of any configuration, does not deform, does not crack and is easy to cut to the required dimensions, which essentially reduces installation costs and installation time itself, and in appearance it is indistinguishable from natural stone or wood.

Procedeul se realizează în modul următor. The procedure is carried out in the following way.

Exemplul 1 Example 1

În prealabil se prepară un liant anorganic pe baza unui amestec conţinând un liant anorganic, o soluţie apoasă de dispersie acrilică, un component silicios. Într-un malaxor cu rotor-stator de mare viteză se încarcă materie primă: nisip cuarţos cu dimensiunea particulelor de 5…30,0 µm, ciment alb cu marca 52,5R şi moloz - deşeuri de la producerea marmurei cu dimensiunea particulelor de 20…50 µm. Concomitent se mai încarcă o soluţie apoasă de dispersie acrilică în raportul 1:1. Se realizează amestecarea intensivă a acestui amestec la viteza de agitare de cel puţin 1500 rot/min şi frecvenţa oscilaţiilor particulelor amestecate de 2000…35000 Hz în timp suficient pentru a atinge densitatea necesară de 1,2 g/cm3 timp de 10…30 min. Drept rezultat, amestecul se supune la acţiunea percutant-tangenţială cu obţinerea unui produs omogen uniform. First, an inorganic binder is prepared based on a mixture containing an inorganic binder, an aqueous solution of acrylic dispersion, a siliceous component. Raw materials are loaded into a high-speed rotor-stator mixer: quartz sand with a particle size of 5…30.0 µm, white cement of the 52.5R brand and rubble - waste from marble production with a particle size of 20…50 µm. At the same time, an aqueous solution of acrylic dispersion is also loaded in a 1:1 ratio. Intensive mixing of this mixture is carried out at a stirring speed of at least 1500 rpm and a frequency of oscillation of the mixed particles of 2000…35000 Hz for a time sufficient to achieve the required density of 1.2 g/cm3 for 10…30 min. As a result, the mixture is subjected to percussive-tangential action with the obtaining of a uniform homogeneous product.

Apoi, acest produs obţinut se aplică pe o formă pregătită preliminar cu dimensiunea de 1,2 m x 0,6 m şi grosimea stratului de 0,5 cm. Deasupra se acoperă cu un material intermediar neţesut cu densitatea de 60 g/cm3 şi deasupra din nou se toarnă liantul. Materialul pe întregul volum este apoi supus tratamentului termic cu ajutorul unui generator de frecvenţă foarte înaltă timp de 20…25 s la o frecvenţă de 2450 MHz şi la o temperatură de 20…180°C cu evaporarea simultană a aerului prin vidare. Apoi materialul obţinut se menţine timp de 20 min la o temperatură de 25…30°C. Then, this obtained product is applied to a pre-prepared form with dimensions of 1.2 m x 0.6 m and a layer thickness of 0.5 cm. On top, it is covered with an intermediate non-woven material with a density of 60 g/cm3 and the binder is poured on top again. The material over the entire volume is then subjected to heat treatment using a very high frequency generator for 20…25 s at a frequency of 2450 MHz and at a temperature of 20…180°C with simultaneous evaporation of air by vacuum. Then the obtained material is maintained for 20 min at a temperature of 25…30°C.

După aceasta materialul se separă de la formă şi se taie în plăci de dimensiuni prestabilite. Drept rezultat, se obţine un material elastic cu coeficientul de conductibilitate termică λ = 0,137 W/mK, care poate fi îndoit repetat la orice grad fără formarea fisurilor. After this, the material is separated from the mold and cut into plates of predetermined dimensions. As a result, an elastic material with a thermal conductivity coefficient of λ = 0.137 W/mK is obtained, which can be repeatedly bent to any degree without the formation of cracks.

Exemplul 2 Example 2

Este analogic cu exemplul 1. Totuşi, numărul de straturi de liant anorganic este mai mare de trei. Totodată, timpul de expunere cu ajutorul generatorului de frecvenţă foarte înaltă constituie 30…40 s. Materialul se menţine apoi la temperatura de 32…38°C timp de 30…40 min. Drept rezultat, se obţine un material mai dens, utilizat pentru montajul ariilor mari cu suprafaţă plană. It is analogous to example 1. However, the number of layers of inorganic binder is more than three. At the same time, the exposure time with the help of a very high frequency generator is 30…40 s. The material is then maintained at a temperature of 32…38°C for 30…40 min. As a result, a denser material is obtained, which is used for mounting large areas with a flat surface.

Proprietăţile fizice ale materialului obţinut conform exemplelor menţionate sunt identice. The physical properties of the material obtained according to the mentioned examples are identical.

Utilizarea materialului obţinut prin procedeul solicitat sporeşte esenţial posibilităţile arhitecţilor, designerilor, constructorilor în construcţia şi arhitectura modernă. Utilizarea procedeului permite nu numai de a îmbunătăţi ambianţa locuinţelor din contul utilizării unui material flexibil, uşor, ecologic pur, care imită complet piatra naturală şi lemnul natural, dar şi de a spori izolarea termică a clădirilor şi a le proteja suplimentar de umezeală şi alte acţiuni atmosferice. The use of the material obtained by the requested process significantly increases the possibilities of architects, designers, builders in modern construction and architecture. The use of the process allows not only to improve the ambience of homes due to the use of a flexible, lightweight, ecologically pure material that completely imitates natural stone and natural wood, but also to increase the thermal insulation of buildings and additionally protect them from moisture and other atmospheric influences.

1. EA 200900006 A1 2010.06.30 1. EA 200900006 A1 2010.06.30

2. US 2012171428 A1 2012.07.05 2. US 2012171428 A1 2012.07.05

Claims (1)

Procedeu de fabricare a materialului de construcţie de finisare, care include amestecarea liantului anorganic şi/sau mijloacelor auxiliare cu nisip cuarţos cu obţinerea unui material omogen, formarea materialului cu armarea lui concomitentă printr-un material intermediar, şi tratamentul termic, caracterizat prin aceea că tratamentul termic se efectuează pe întregul volum al materialului cu ajutorul unui generator de frecvenţă foarte înaltă, la o frecvenţă de 2450 MHz, timp de 20…40 s, la o temperatură de 20…180°C, cu evaporarea simultană a aerului prin vidare, precum şi cu menţinerea ulterioară a materialului obţinut la o temperatură de 25…38°C timp de 20…40 min.Process for manufacturing finishing building material, which includes mixing inorganic binder and/or auxiliary means with quartz sand to obtain a homogeneous material, forming the material with its simultaneous reinforcement by an intermediate material, and heat treatment, characterized in that the heat treatment is performed on the entire volume of the material using a very high frequency generator, at a frequency of 2450 MHz, for 20…40 s, at a temperature of 20…180°C, with simultaneous evaporation of air by vacuum, as well as with subsequent maintenance of the obtained material at a temperature of 25…38°C for 20…40 min.
MDS20150077A 2015-06-10 2015-06-10 Method for the production of building decoration material MD998Z (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
MDS20150077A MD998Z (en) 2015-06-10 2015-06-10 Method for the production of building decoration material
PCT/MD2016/000001 WO2016200247A1 (en) 2015-06-10 2016-01-13 Process for producing a building finishing material
IL252180A IL252180A (en) 2015-06-10 2017-05-09 Process for producing a building finishing material

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
MDS20150077A MD998Z (en) 2015-06-10 2015-06-10 Method for the production of building decoration material

Publications (2)

Publication Number Publication Date
MD998Y MD998Y (en) 2016-01-31
MD998Z true MD998Z (en) 2016-08-31

Family

ID=55235468

Family Applications (1)

Application Number Title Priority Date Filing Date
MDS20150077A MD998Z (en) 2015-06-10 2015-06-10 Method for the production of building decoration material

Country Status (3)

Country Link
IL (1) IL252180A (en)
MD (1) MD998Z (en)
WO (1) WO2016200247A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MD1317Z (en) * 2018-03-29 2019-09-30 Александр КОТЛЯРОВ Process for protective finishing of building structures

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MD20070299A (en) * 2007-11-05 2009-07-31 Vitalie Cotelea Composition for decorative coating of the building elements, process for obtaining and application of the decorative coating
EA200900006A1 (en) * 2008-11-21 2010-06-30 Валерий Григорьевич Глига METHOD OF OBTAINING CONSTRUCTION AND FINISHING MATERIAL AND PRODUCTS OF SILICON BREEDS
US20120171428A1 (en) * 2009-06-02 2012-07-05 Holger Marohn Method for Producing a Visible Covering

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2085866B (en) * 1980-10-21 1984-12-12 Teubert Juergen Hardening bodies made from a mixture of building materials with mineral components
US9067383B2 (en) * 2004-09-16 2015-06-30 United States Gypsum Company Flexible and rollable cementitious membrane and method of manufacturing it
JP5578975B2 (en) 2010-07-16 2014-08-27 キヤノン株式会社 Information processing apparatus, processing method thereof, and program
WO2014024259A1 (en) * 2012-08-07 2014-02-13 株式会社エスイー Process for producing concrete formed body

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MD20070299A (en) * 2007-11-05 2009-07-31 Vitalie Cotelea Composition for decorative coating of the building elements, process for obtaining and application of the decorative coating
EA200900006A1 (en) * 2008-11-21 2010-06-30 Валерий Григорьевич Глига METHOD OF OBTAINING CONSTRUCTION AND FINISHING MATERIAL AND PRODUCTS OF SILICON BREEDS
US20120171428A1 (en) * 2009-06-02 2012-07-05 Holger Marohn Method for Producing a Visible Covering

Also Published As

Publication number Publication date
WO2016200247A1 (en) 2016-12-15
IL252180A (en) 2017-12-31
IL252180A0 (en) 2017-06-29
MD998Y (en) 2016-01-31

Similar Documents

Publication Publication Date Title
CN102561532A (en) Functionally-graded cellular-concrete thermal-insulating material and preparation method thereof
US20060083591A1 (en) Method of forming surface seeded particulate
CN104131680A (en) Special floor for magnesium container house and manufacturing method of special floor
CN103240927B (en) Reinforced cement machine-made board with three-dimensional cavity fiber structure and production method of board
KR101172820B1 (en) Manufacturing process of incombustible concrete panel using coated EPS lightweight aggregate
CN111734046A (en) Foamed ceramic composite panel and its preparation method and building wall panel
CN105347732A (en) Antifreeze durable resin and concrete composite water-permeable floor tile
CN104695659B (en) Imitating stone type foaming cement heat-preservation and decoration integrated board and manufacturing method thereof
CN104343219A (en) Inorganic polymer composite board
CN102828597A (en) Stone-saving artificial granite integral decorative plate and production method thereof
CN110395957A (en) A kind of EPS lightweight aggregate thermal insulation and decoration integrated board and preparation method thereof
KR101181433B1 (en) Method for manufacturing FRP artifical stone and FRP artifical stone manufactured thereby
MD998Z (en) Method for the production of building decoration material
CN110451916A (en) A kind of expanded perlite light thermal insulation decoration integrated board and preparation method thereof
CN106866043A (en) A kind of environmental-friendly construction material
EA017880B1 (en) Dry decorative finishing mixture
CN102797335B (en) Integrated decorating plate of energy-saving stone and artificial sandstone and production method thereof
CN106626599A (en) Silicon dioxide aerogel sandwich plasterboard and manufacturing method thereof
CN208056619U (en) A kind of multi-layer fireproofing thermal insulation board and the heat insulation decoration integrated plate comprising multi-layer fireproofing thermal insulation board and self-heat conserving cast-in-situ template
CN106759962A (en) A kind of environment-friendly waterproof sheet material and preparation method thereof
CN102653973A (en) Sintering-free exterior wall face brick with thermal insulation function and low water absorption rate
CN105271999A (en) Simulation stone for thermal insulation of buildings and production method of simulation stone
CN106542779B (en) A kind of light thermal-insulation exposed wall facing brick and its production technology
CN202831495U (en) Energy-saving stone and imitation sandstone integration decorative plate
CN105216096A (en) A kind of preparation method of baking-free ceramic tempering minute surface non-metal sound barrier

Legal Events

Date Code Title Description
FG9Y Short term patent issued
KA4Y Short-term patent lapsed due to non-payment of fees (with right of restoration)
NF4Y Restoration of lapsed short term patent
ND4Y Validity of short term patent extended [from 6 to 10 years]

Expiry date: 20250610

MK4Y Short term patent expired