KR20010097546A - Method of preparing low-voltage red phosphor - Google Patents

Method of preparing low-voltage red phosphor Download PDF

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KR20010097546A
KR20010097546A KR1020000021711A KR20000021711A KR20010097546A KR 20010097546 A KR20010097546 A KR 20010097546A KR 1020000021711 A KR1020000021711 A KR 1020000021711A KR 20000021711 A KR20000021711 A KR 20000021711A KR 20010097546 A KR20010097546 A KR 20010097546A
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salt
phosphor
red phosphor
flux
mgco
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KR100649242B1 (en
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유일
유영철
유용찬
박규찬
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김순택
삼성에스디아이 주식회사
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    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
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    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/50—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on rare-earth compounds
    • 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
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/64—Burning or sintering processes
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
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    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
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    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

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Abstract

본 발명은 저전압용 적색 형광체의 제조 방법에 관한 것으로서, 이 제조 방법은 스트론튬염, 티타늄염, 프라세오디뮴염, 알루미늄염과 MgCO3를 혼합하고, 상기 혼합물을 1100 내지 1400℃에서 소성하는 공정을 포함한다.The present invention relates to a method for producing a red phosphor for low voltage, the method comprising mixing strontium salt, titanium salt, praseodymium salt, aluminum salt and MgCO 3 and calcining the mixture at 1100 to 1400 ℃. .

상기한 방법으로 제조된 적색 형광체는 휘도가 향상된 형광체이다.The red phosphor prepared by the above method is a phosphor having improved luminance.

Description

저전압용 적색 형광체의 제조 방법{METHOD OF PREPARING LOW-VOLTAGE RED PHOSPHOR}METHOOD OF PREPARING LOW-VOLTAGE RED PHOSPHOR}

[산업상 이용 분야][Industrial use]

본 발명은 저전압용 적색 형광체의 제조 방법에 관한 것으로서, 더욱 상세하게는 휘도가 우수한 저전압용 적색 형광체를 제조할 수 있는 저전압용 적색 형광체의 제조 방법에 관한 것이다.The present invention relates to a method of manufacturing a low voltage red phosphor, and more particularly, to a method of manufacturing a low voltage red phosphor capable of producing a low voltage red phosphor having excellent luminance.

[종래 기술][Prior art]

주로 1kV 이하의 저전압 디스플레이에는 진공 형광 디스플레이(Vaccumm Fluoresent Display: VFD), 전계 방출 디스플레이(Field Emission Display: FED) 등이 있다. VFD는 주로 가전, AV, 자동차 등의 각종 표시 소자로 사용되고 있고 FED는 차세대 소형 평판 표시 소자로 활발히 연구되고 있다.Low voltage displays of less than 1 kV include vacuum fluorescence displays (VFDs) and field emission displays (FEDs). VFD is mainly used for various display devices such as home appliances, AV, automobiles, etc., and FED is being actively researched as a next-generation small flat panel display device.

이러한 VFD 및 FED에 사용되는 적색 형광체로는 ZnS:Zn 등의 황화아연계 형광체, Y2O3:Eu 형광체 및 SrTiO3:Pr,Al 형광체가 있다. 이 형광체 중에서 SrTiO3:Pr,Al 형광체가 디스플레이 내부 및 환경 오염 문제가 발생하지 않으므로 최근 활발히 연구되고 있다.Red phosphors used in such VFD and FED include zinc sulfide-based phosphors such as ZnS: Zn, Y 2 O 3 : Eu phosphors, and SrTiO 3 : Pr, Al phosphors. Among these phosphors, SrTiO 3 : Pr, Al phosphors have been actively studied recently because they do not cause problems in the display and environmental pollution.

SrTiO3:Pr,Al 형광체는 모체 SrTiO3와 부활제 Pr 및 공부활제 Al으로 구성된 형광체로서, 스트론튬염과 티타늄염 및 부활제로 프라세오디뮴(Pr)염과 공부활제로 Al을 혼합하고 이 혼합물을 1100 내지 1400℃에서 소성하여 제조된다.SrTiO 3 : Pr, Al phosphor is a phosphor composed of parent SrTiO 3 , an activator Pr, and a study Al. It is produced by firing at 1400 ° C.

그러나 이 방법으로 제조된 화합물은 휘도가 만족할만한 수준에 도달하지 못하고 있다.However, the compounds produced by this method do not reach satisfactory levels of luminance.

본 발명은 상기한 문제점을 해결하기 위한 것으로서, 본 발명의 목적은 휘도가 우수한 저전압용 적색 형광체의 제조 방법을 제공하는 것이다.SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for producing a low phosphor red phosphor having excellent luminance.

상기 본 발명의 목적을 달성하기 위하여, 본 발명은 스트론튬염, 티타늄염, 프라세오디뮴염, 알루미늄염과 MgCO3를 혼합하고; 상기 혼합물을 1100 내지 1400℃에서 소성하는 공정을 포함하는 저전압용 적색 형광체의 제조 방법을 제공한다.In order to achieve the object of the present invention, the present invention is mixed with strontium salt, titanium salt, praseodymium salt, aluminum salt and MgCO 3 ; It provides a method for producing a low-voltage red phosphor comprising the step of firing the mixture at 1100 to 1400 ℃.

이하, 본 발명의 제조 방법을 상세히 설명한다.Hereinafter, the manufacturing method of the present invention will be described in detail.

스트론튬염, 티타늄염과 부활제로 프라세오디뮴염, 공부활제로 알루미늄염 및 융제로 MgCO3를 혼합한다.Strontium salt, titanium salt and praseodymium salt as activator, aluminum salt as study agent and MgCO 3 as flux are mixed.

이때 스트론튬염과 티타늄염은 동몰량으로 사용하는 것이 바람직하며, 스트론튬염과 티타늄염을 동몰량으로 사용하지 않으면 원하는 물성을 갖는 형광체가 제조되지 않을 수 있다. 상기 프라세오디뮴염은 0.1 내지 0.5 몰%로 사용하고, 상기알루미늄염은 5 내지 20 몰%로 사용한다. 또한, 상기 융제인 MgCO3는 티타늄염 중량의 0.5 내지 3 중량%로 사용한다. 융제의 양이 0.5 중량% 미만인 경우에는 휘도 증가가 미미하고, 3 중량%를 초과하는 경우에는 휘도가 감소하는 문제점이 있다.At this time, the strontium salt and the titanium salt is preferably used in an equimolar amount, and if the strontium salt and the titanium salt are not used in an equimolar amount, phosphors having desired physical properties may not be prepared. The praseodymium salt is used in 0.1 to 0.5 mol%, the aluminum salt is used in 5 to 20 mol%. In addition, the flux MgCO 3 is used in 0.5 to 3% by weight of the titanium salt. If the amount of flux is less than 0.5% by weight, there is a problem that the increase in brightness is insignificant, and if it exceeds 3% by weight, the brightness is decreased.

본 발명에서 사용한 융제(flux)란 형광체의 입경을 성장시키고, 입형을 조절하는 역할을 하는 화합물을 말하며, 이와 같이 융제를 사용하여 형광체의 결정성과 입형을 조절할 수 있으므로 얻어지는 형광체의 휘도를 증가시킬 수 있다.Flux used in the present invention refers to a compound that grows the particle diameter of the phosphor and controls the shape of the phosphor. As such, the flux can control the crystallinity and the shape of the phosphor to increase the luminance of the obtained phosphor. have.

상기 스트론튬염으로는 SrCO3또는 Sr(NO3)2가 사용될 수 있고, 상기 티타늄염으로는 TiO2가 사용될 수 있으며, 상기 프라세오디뮴염으로는 PrCl3또는 PrF3가 사용될 수 있다.SrCO 3 or Sr (NO 3 ) 2 may be used as the strontium salt, TiO 2 may be used as the titanium salt, and PrCl 3 or PrF 3 may be used as the praseodymium salt.

상기 혼합물을 1100 내지 1400℃에서 1 내지 6시간 동안 소성한다. 소성 공정은 대기 분위기, 또는 H2가스의 환원 분위기에서 실시할 수 있다. 이 소정 공정에서, SrTiO3의 매트릭스가 형성되며, 적색 발광 영역을 갖는 Pr이 이 매트릭스 내부로 도핑된다. 이때, 융제는 휘발되어 제거된다.The mixture is calcined at 1100-1400 ° C. for 1-6 hours. The firing step can be performed in an atmospheric atmosphere or in a reducing atmosphere of H 2 gas. In this predetermined process, a matrix of SrTiO 3 is formed, and Pr having a red light emitting region is doped into this matrix. At this time, the flux is removed by volatilization.

제조된 매트릭스는 일부가 덩어리져있을 수 있으므로, 밀링(milling) 공정을 실시할 수 있다. 밀링 공정은 볼밀(ball-mill)을 실시하는 것이 응집된 입자를 제거하고 분산성 및 입도 분포를 향상시킬 수 있어 바람직하다.Since the prepared matrix may be agglomerated in part, the milling process can be performed. The milling process is preferably carried out by ball milling to remove aggregated particles and to improve dispersibility and particle size distribution.

이어서, 소성 공정에서 융제가 남아 있을 수 있으므로, 세정 공정을 더욱 실시할 수 있다. 세정 공정은 밀링한 물질을 산으로 세정하여 잔존하는 융제를 제거한다. 상기 산으로는 일반적으로 형광체 제조 공정에서 융제를 제거하기 위해 사용되는 것은 어떠한 것도 사용할 수 있으며, 그 대표적인 예로는 약 0.5N 농도의 질산 또는 약 1% 농도의 염산을 사용할 수 있다.Subsequently, the flux may remain in the firing step, so that the washing step may be further performed. The cleaning process washes the milled material with acid to remove remaining flux. In general, any of the acids used to remove the flux in the phosphor manufacturing process may be used, and representative examples thereof may include nitric acid at about 0.5N concentration or hydrochloric acid at about 1% concentration.

이어서, 형광체의 결정성을 증가시켜 형광체의 발광 효율을 향상시키기 위하여 소성 공정을 1회 더 실시한다. 이 소성 공정은 질산 또는 염산으로 세정한 물질을 H2가스 또는 N2가스의 환원 분위기 하에서 800 내지 1100℃의 온도로 1 내지 2시간 동안 소성하여 실시한다.Subsequently, in order to increase the crystallinity of the phosphor and to improve the luminous efficiency of the phosphor, the firing step is further performed. This firing step is carried out by firing the material washed with nitric acid or hydrochloric acid for 1 to 2 hours at a temperature of 800 to 1100 ℃ in a reducing atmosphere of H 2 gas or N 2 gas.

제조된 물질을 형광체로 사용할 수 도 있으나, 도전성을 더욱 증가시키기 위하여 In2O3또는 ITO(indium tin oxide)와 같은 도전성 물질과 혼합하여 사용할 수 도 있다. 이때, 도전성 물질의 첨가량은 제조된 SrTiO3:Pr,Al 중량의 5 내지 20 중량%로 한다.The prepared material may be used as a phosphor, but may be mixed with a conductive material such as In 2 O 3 or indium tin oxide (ITO) to further increase conductivity. At this time, the addition amount of the conductive material is 5 to 20% by weight of the manufactured SrTiO 3 : Pr, Al weight.

상기 소성된 물질을 시브(sieve)를 사용하여 분급함으로써 저전압용 적색 형광체를 제조한다.The calcined material is classified using a sieve to prepare a red phosphor for low voltage.

이와 같이, 본 발명에서는 융제로 MgCO3를 사용하여 종래 융제를 사용하지 않고 제조된 SrTiO3:Pr,Al에 비해 휘도가 높은 SrTiO3:Pr,Al 형광체를 제조할 수 있다.As described above, in the present invention, the SrTiO 3 : Pr, Al phosphor having a higher luminance than the SrTiO 3 : Pr, Al manufactured without using a conventional flux using MgCO 3 as a flux can be prepared.

이하 본 발명의 바람직한 실시예 및 비교예를 기재한다. 그러나 하기한 실시예는 본 발명의 바람직한 일 실시예일 뿐 본 발명이 하기한 실시예에 한정되는것은 아니다.Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

(실시예 1)(Example 1)

SrCO31몰, TiO21몰, PrCl30.1몰, Al(OH)310몰 및 MgCO3를 혼합하였다. 이때, MgCO3는 SrCO3와 TiO2혼합 중량의 1 중량%의 양으로 사용하였다. 이 혼합물을 대기 분위기 하에서 1200℃의 온도로 3시간동안 1차 소성하였다. 1차 소성한 물질을 3시간 동안 볼밀을 실시한 후, 1% 농도의 염산으로 세정하였다. 산으로 세정한 물질을 H2가스에서 1000℃의 온도로 2시간 동안 2차 소성하였다. 2차 소성된 물질을 분급하여 저전압용 적색 형광체를 제조하였다.1 mol of SrCO 3, 1 mol of TiO 2 , 0.1 mol of PrCl 3 , 10 mol of Al (OH) 3 and MgCO 3 were mixed. At this time, MgCO 3 was used in an amount of 1% by weight of the mixed weight of SrCO 3 and TiO 2 . The mixture was first calcined for 3 hours at an temperature of 1200 ° C. under an atmospheric atmosphere. The first calcined material was ball milled for 3 hours, and then washed with 1% hydrochloric acid. The acid washed material was calcined for 2 hours at a temperature of 1000 ° C. in H 2 gas. The secondary fired material was classified to prepare a red phosphor for low voltage.

(비교예 1)(Comparative Example 1)

SrCO31몰, TiO21몰, PrCl30.1몰 및 Al(OH)310몰을 혼합하였다. 이 혼합물을 대기 분위기 하에서 1200℃의 온도로 3시간동안 소성하였다. 소성된 물질을 분급하여 저전압용 적색 형광체를 제조하였다.1 mol of SrCO 3, 1 mol of TiO 2 , 0.1 mol of PrCl 3 and 10 mol of Al (OH) 3 were mixed. The mixture was calcined for 3 hours at an temperature of 1200 ° C. under an atmospheric atmosphere. The calcined material was classified to prepare a red phosphor for low voltage.

상기 실시예 1 및 비교예 1의 방법으로 제조된 적색 형광체의 휘도를 측정한 결과 실시예 1의 형광체의 휘도가 비교예 1의 형광체의 휘도보다 100V 구동 조건에서 20% 증가하였다.As a result of measuring the luminance of the red phosphors prepared by the method of Example 1 and Comparative Example 1, the luminance of the phosphor of Example 1 was increased by 20% at 100V driving conditions than the luminance of the phosphor of Comparative Example 1.

상술한 바와 같이, 본 발명의 제조 방법은 융제를 사용하여 향상된 휘도를 갖는 저전압용 적색 형광체를 제조할 수 있다.As described above, the production method of the present invention can produce a low-voltage red phosphor having an improved luminance by using a flux.

Claims (2)

스트론튬염, 티타늄염, 프라세오디뮴염, 알루미늄염과 MgCO3를 혼합하고;Strontium salt, titanium salt, praseodymium salt, aluminum salt and MgCO 3 are mixed; 상기 혼합물을 1100 내지 1400℃에서 소성하는Calcining the mixture at 1100 to 1400 ° C. 공정을 포함하는 저전압용 적색 형광체의 제조 방법.The manufacturing method of the red fluorescent substance for low voltages containing a process. 제 1 항에 있어서, 상기 MgCO3의 양은 티타늄염 중량의 0.5 내지 3 중량%인 제조 방법.The method of claim 1, wherein the amount of MgCO 3 is 0.5 to 3% by weight of the titanium salt.
KR1020000021711A 2000-04-24 2000-04-24 Method of preparing low-voltage red phosphor KR100649242B1 (en)

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JPS5947288A (en) * 1982-09-10 1984-03-16 Toshiba Corp Fluophor
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JP3790854B2 (en) * 1998-04-01 2006-06-28 化成オプトニクス株式会社 Strontium titanate phosphor
JP2000144130A (en) * 1998-09-01 2000-05-26 Nichia Chem Ind Ltd Red light-emitting fluorescent material and luminous screen using the same

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