baber/WOPTO huggingface dataset:
Patent KR-20000020181-A (KR)
Title: Integrated structure of printed circuit board
Inventor: CHO YOUNG MIN
IPC: H05K3/40
Filed: 1998-09-18
Abstract: PURPOSE: An integrated structure of a printed circuit board is provided to utilize a narrow space of the printed circuit board by installing a via hole for connecting a circuit line of each layer on the printed circuit board where a switching terminal is installed. CONSTITUTION: A switching terminal(20) has a copper foil(22) formed to expose an upper part of a film(21) to the exterior and a lead provided on both ends of the copper foil and coupled to a predetermined circuit(13) on the printed circuit board(10). A key pad(30) installed spaced apart from the switching terminal has a carbon layer(32) formed on an opposed plane to the switching terminal, and is closely connected to the switching terminal according to a push by a user so as to flow a predetermined electric signal. At least one via hole(15) electrically connects a circuit line of a layer to the printed circuit board where the switching terminal is installed.
Patent KR-19990029999-A (KR)
Title: 기지국 및 하나 이상의 송수화기를 구비한 전화 시스템에 이러한 시스템을 실행하는 방법, 이러한 시스템에 적합한 가입자 스테이션 및 기지국
IPC: H04W88/02
Filed: 1998-09-21
Abstract: 호출 신호의 교환을 허가하기 위한 본 전화 시스템은 기지국(1) 및 하나 이상의 송수화기(2, 3 ...)를 포함한다. 본 시스템은, 스테이션 사이의 호출 신호(51, 26-52, 40)에서의 중첩된 신호 프레임(frame)을 송신하기 위한 수단과, 신호 프레임(55, 61-56, 62)을 수신하는 동안 호출 신호를 차단하기 위한 수단을 구비한다. 더욱이, 송수화기(2)에는 호출 신호의 차단과 상기 신호 프레임의 수신 사이의 시간 간격을 측정하기 위한 차동 회로(66)가 제공된다. 그러므로 상기 차동의 함수로써 상기 차단의 출현을 변경하기 위한 정정은 회로(62)에서 소개된다. 
     응용: 무선 전화
Patent KR-19980087888-A (KR)
Title: 과실보호커버
Filed: 1998-09-26
Abstract: 본 발명은 과실보호커버에 관한 것으로서, 더욱 상세하게는 과수(果樹)에 열리는 과실에 종이봉지를 씌워주던 것을 합성수지재로 형성된 보호커버를 착탈가능하게 씌워줌으로서, 조류나 우박등으로 부터 과실(果實)이 손상되는 것을 방지 하기 위한 것이다. 
     상기 본 발명에 의한 과실보호커버는, 두 개의 반구형 몸체(2)가 서로 마주보게 형합되어 구형상을 이루도록 일측 접선부위에 힌지부(3)를 형성하여 두 개의 반구형 몸체(2)가 개폐가능하게 하고, 힌지부(3) 반대측의 일측 몸체(2)의 접선부에 걸림부(4)를 형성하고 타측 몸체(2)의 접선부에는 상기 걸림부(4)에 착탈식으로 끼워질 걸림구(5)를 형성하여 양측 몸체(2)의 형합상태를 록킹 해제시키도록 되며, 두 개의 몸체(2)가 형합되는 상측 중앙부에는 과실꼭지(12)가 인출될 과실꼭지 인출구멍(6)이 형성된 것을 특징으로 한다.
Patent KR-20000021419-A (KR)
Title: Method of trench isolation using nitride diffusion
Inventor: WON DAE HEI
IPC: H01L21/76
Filed: 1998-09-29
Abstract: PURPOSE: A method of a trench ioslation using a nitride diffusion is provided to suppress a stress induced in a semiconductor substrate by preventing an oxide gas from diffusing to a silicon of a trench at a thermal process after a trench isolation. CONSTITUTION: A method of a trench isolation includes a first through fourth steps. The first step is to form a trench(104) by selectively etching a semiconductor substrate(101). The second step is to form a thermal oxide layer(105) on the surface of the semiconductor substrate of the trench area. The third step is to diffuse nitride into a boundary between the semiconductor substrate and the thermal oxide layer by annealing at a circumstances of gas including a nitride atom. The fourth step is to bury an insulating layer for isolating components within the trench. The annealing at the third step is performed at a NH3 circumstances.
Patent KR-20000021641-A (KR)
Title: Control structure of opening angle of hanger for transporting vehicle body
Inventor: KIM JAE U
IPC: B66C1/62
Filed: 1998-09-30
Abstract: PURPOSE: A control structure is provided to avoid interference quickly and easily by controlling an angle of a hanger arm in occurring the interference with other equipment as operating the hanger arm. CONSTITUTION: When a hanger arm(27) is opened or closed by a rotary member(21C) and an operation cylinder(21B) established in a bracket(21A) of a transporter(21), if the lower part of the hanger arm(27) cannot be operated normal by an interference with other equipment, the interference is avoided quickly and easily by easily controlling an opening angle of the hanger arm(27) by fastening or releasing a control bolt(39) of an angle controller(30) established between a filler block(29) and a connection member(24).
Patent KR-20000024883-A (KR)
Title: Method for manufacturing thin film type actuated mirror arrays
Inventor: SHON SUNG YONG
IPC: G02F1/015
Filed: 1998-10-02
Abstract: PURPOSE: A method for manufacturing an actuated mirror arrays(AMA) is provided to enhance driving characteristics of an actuator through an exact forming of a first and a second contorted beds and to prevent point defects of pixels by removing polymer occurred during an etching process for patterning of a second layer. CONSTITUTION: An active matrix(100) including a first metal layer(135) is provided. A first layer, a lower electrode layer(180), a second layer, and an upper electrode layer are formed on the active matrix(100). A first upper electrode(200) and a second upper electrode are formed by patterning the upper electrode layer. The second layer is patterned into a first contorted bed(190) and a second contorted bed. Polymer occurring during the second layer is removed. An actuator(210) is formed by patterning the lower electrode(180). A support part(170) is formed by patterning the first layer. A second sacrificial layer(300) is formed, patterned to form a mirror(260) thereon.
Patent KR-19990036876-A (KR)
Title: 반도체 장치 및 그 제조방법
IPC: H01L21/68
Filed: 1998-10-02
Abstract: 본 발명은 반도체 장치의 제조방법을 제공하는 것을 목적으로 한다. 웨이퍼를 다이아몬드 블레이드를 사용하여 개개의 단편으로 분할한 후에, 각 단편 사이의 간격을 포함시킨 웨이퍼의 표면 전체를 수지로 밀봉하고, 다른 다이아몬드 블레이드보다도 폭이 좁은 다이아몬드 블레이드를 사용하여 웨이퍼를 다시 개개의 단편으로 분할함으로써, 칩의 1개의 측면 상에 수지를 남긴 상태의 칩 사이즈 패키지를 얻을 수 있다. 또한, 상술한 방법에 따르면, 칩 측면이 수지로 밀봉된 상태의 칩 사이즈 패키지를 용이하게 제조할 수 있다.
Patent KR-20000025788-A (KR)
Title: Structure of fire propagation of gas burner
Inventor: CHO HYEON JU
IPC: F23D14/56
Filed: 1998-10-14
Abstract: PURPOSE: A fire propagating structure of a gas burner is provided to maintain the fire propagating flames stably in a fire propagating part and to prevent the occurrence of lifting due to the excessive gas eruption speed. CONSTITUTION: A gas is supplied via a gas supply path(12) of a burner body(10) according to the operation of an operation knob of a gas burner. The gas is delivered to flame holes(25,25') on both sides of the body. And the gas erupted from the flame holes is burned and forms flames according to the generation of spark in an ignition electrode placed on one flame hole(25). The fire propagating to the flame holes is performed by the flames. Then, the eruption speed of the gas via a second eruption hole is decelerated much while the gas is erupted to a second eruption hole(80) by passing through a gas inducement chamber. The flowing speed is decelerated while being flowed into the gas inducement chamber from the gas supply chamber, and more while continuously passing through the first eruption hole and the second eruption hole.
Patent KR-20000026782-A (KR)
Title: Method for formatting optical recording medium and managing fault region
Inventor: PARK YONG CHEOL
IPC: G11B20/12
Filed: 1998-10-20
Abstract: PURPOSE: A method for formatting optical recording medium and managing defect region is provided to decrease the probability of an overflow of a DMA and improve a system performance by converting only sector number of a first sector of a defect block recorded in an SDL into a PDL and performing a slipping alternation of 16 sectors having a defect sector when a flag is set as 1. CONSTITUTION: If a simple formatting method is selected when performing a reformat(601), previous DMA information is read and defect sectors recorded in a P-list of a previous PDL is recorded in the P-list of a new PDL, and then defect sectors recorded in a G1-list of the previous PDL is recorded in the G1-list of the new PDL(602). defect sectors recorded in a G2-list of the previous PDL are recorded in the G2-list of the new PDL(603). Only sector number of a first sector of a defect block recorded in the previous SDL is recorded in the G2-list of the new PDL and residual 15 sectors are not recorded, and then a G2F flag is set as 1 and a corresponding SDL entry is removed(604). If an overflow is occurred in the G2-list of the new PDL(605), residual previous entries are recorded in the new SDL entry(606). The simply formatting for converting the SDL into the G2-list of the PDL is completed(607).
Patent KR-19990045544-A (KR)
Title: 스퍼터링 장치 및 이것을 이용한 엠오에스 트랜지스터를 갖는 반도체장치의 제조방법
IPC: H01L21/285
Filed: 1998-11-25
Abstract: 도전층은 반도체 기판 위에 게이트 전극이 형성될 영역 및 소스 및 드레인 확산층이 형성될 영역에 형성된다.  그 후, 금속막은 스퍼터링용 타겟과 도전층 사이에, 접지된 챠지 트랩부재를 구비하고 상기 타겟을 스퍼터링하는 것에 의해 형성된다.
Patent KR-19990045596-A (KR)
Title: 스퍼터링 및 아크 증착용 장치
Filed: 1998-11-26
Abstract: 본 발명은 코팅 침착이나 이온 처리를 위해 증발이나 플라즈마 소스로 사용되는 선형 마그네트론 캐소드에 관한 것이다.  상기 캐소드는 2개의 대향측부를 따라 양단부 주위에서 바아의 원주 주위로 권취되는 증착면으로부터 발생되는 재료의 기화에 의해 신장된 장방형 바아의 형태를 취한다.  자장은 전체 증착면위에 설정되며, 이러한 증착면에 평행하고 캐소드의 길이방향 축선에 수직하며 아크나 스퍼터링 플라즈마 방전을 향하는 원주 주위에 폐쇄루프 자기 터널을 형성하는 성분을 갖는다.  캐소드는 자장 강도와 측부 한정수단을 적절히 선택하므로써 스퍼터링이나 캐소드 아크 증착을 위한 형태를 갖는다.  본 발명은 신장된 길이에 대해 양방향으로 증착된 재료 스트림과 균일한 캐소드 부식을 제공하며, 넓은 영역에 균일한 침착이나 주입을 허용한다.  또한, 양방향 증기 방출 분포의 효과적인 사용을 허용하는 기질 장착과 이동에 대해서도 서술되어 있다.
Patent KR-20000034721-A (KR)
Title: Method for controlling fan in refrigerating chamber
Inventor: PARK HYEONG NAM
IPC: F25D17/06
Filed: 1998-11-30
Abstract: PURPOSE: A controlling method of a fan in a refrigerating chamber is provided to improve cooling speed of a refrigerating chamber by resetting a driving on/off point of a refrigerating chamber sensor at initial operation of a refrigerator or when inputting overload. CONSTITUTION: A temperature sensed in a temperature sensor of a refrigerating chamber is decided to be a certain weak cooling sensing point or not. If the temperature is over the weak cooling sensing point, the driving on/off point is reset and operation is performed by high speed cooling mode. If the temperature is under the weak cooling sensing point, an R fan is decided to be driving or not. If the R fan is not driving, the on point of an R sensor is decided. If the point is driving on, the R fan is driven. If the R fan is driving, the driving off point of the R sensor is decided. If the point is driving off, the driving of the R fan is turned off. If the temperature is over 6°C, the refrigerating chamber starts to be operated by high speed cooling mode.
Patent KR-20000040116-A (KR)
Title: Array structure of thin film transistor liquid crystal display device
Inventor: LEE GYEONG HA
IPC: G02F1/136
Filed: 1998-12-17
Abstract: PURPOSE: An array structure of thin film transistor liquid crystal display device is provided to prevent defects due to a step coverage between a thin film transistor and a storage electrode when rubbing. CONSTITUTION: An array structure of thin film transistor liquid crystal display device includes a lower substrate(20), a gate bus line(21), a data bus line(23), a thin film transistor(25), a pixel electrode(27), a storage electrode(28), and an alignment layer. The gate bus line(21) is extended to an x axis on the lower substrate(20). The data bus line(23) is extended to an y axis on the lower substrate and confines a unit pixel with the gate bus line. The thin film transistor(25) is implemented around the cross section between the gate and data bus lines. The pixel electrode(27) is implemented on the unit pixel area and contacts the thin film transistor. The storage electrode(28) is imposed on a lower portion of the pixel electrode. The alignment layer is implemented on the lower substrate.
Patent KR-20000040843-A (KR)
Title: Method for generating and recording time map information of recording digital data stream
Inventor: YU JE YONG
IPC: G11B20/08
Filed: 1998-12-16
Abstract: PURPOSE: A method for generating and recording the time map information of a recording digital data stream is provided to reduce operating amount while detecting a certain recording data stream while not increasing the size of the time map information in recording the digital data stream to a recording medium. CONSTITUTION: A received digital data stream is recorded in a recording medium. Then, the recorded digital data stream is separated into identifying sized recording units for generating and recording the size information of recording time for each separated recording unit. And the size information of accumulated time from the starting point of the first recording unit to the recording unit of corresponding stream is generated and recorded. Herein, the recording unit is separated by identified number of sectors.
Patent KR-20000041486-A (KR)
Title: Band pass filter
Inventor: KIM OK HYUN
IPC: H03F1/02
Filed: 1998-12-22
Abstract: PURPOSE: A band pass filter is provided to generate an image trap frequency varied according to a channel by use of a voltage controlled diode in order to remove an image frequency. CONSTITUTION: A band pass filter comprises resistors(10,20), blocking capacitances(30,40), inductances(50,60), and voltage controlled diodes(70,80). The resistors(10,20) limit a current from a tuning voltage terminal(Vt), and are connected in parallel with each other. The blocking capacitances(30,40) interrupt a direct current transferred from the tuning voltage terminal to the inductances(50,60). The inductance(50) is connected in series to the voltage controlled diode(70), and the inductance(60) is connected in parallel with the voltage controlled diode(80). Capacitance values of the voltage controlled diodes(70,80) are varied by the tuning voltage terminal(Vt), and the voltage controlled diodes(70,80) generate a resonance frequency and an image trap frequency by a connection with the inductances(50,60).
Patent KR-20000043299-A (KR)
Title: Video signal delay method in satellite broadcast receiver
Inventor: LEE EUNG DON
IPC: H04N7/20
Filed: 1998-12-28
Abstract: PURPOSE: A video signal delay method is provided to output an image and a voice at the same time by delaying a video signal in the case that the video signal is received earlier than the audio signal. CONSTITUTION: A method comprises the steps of: detecting video and audio signals from a received satellite broadcast signal(S102); extracting the video and audio signals of a predetermined time interval from the detected video and audio signals(S103); converting the extracted video and audio signals into digital signals(S104); judging whether the video signal is received earlier than the audio signal based on the digital video and audio signals(S105); and delaying the received video signal by a predetermined time in case that the video signal is received earlier than the audio signal(S107).
Patent KR-20000045449-A (KR)
Title: Method for manufacturing semiconductor device
Inventor: PARK JIN YO
IPC: H01L21/28
Filed: 1998-12-30
Abstract: PURPOSE: A method for manufacturing a semiconductor device is provided to prevent a damage of a semiconductor substrate due to an over-etch and reduce a junction leakage current. CONSTITUTION: A method for manufacturing a semiconductor device comprises the following steps. A MOSFET(Metal Oxide Semiconductor Field Effect Transistor) is formed on a n upper portion of a semiconductor substrate(10). A pad nitride layer and a first interlayer dielectric are formed on a whole surface of the structure. A first photoresist pattern is formed on an upper portion of the first interlayer dielectric. A first bit line contact hole and a storage electrode contact hole are formed by etching the first interlayer dielectric and the pad nitride layer. A second photoresist layer pattern is formed on the upper portion of the whole surface. A metal wiring contact and a second bit line contact hole are formed by etching the first interlayer dielectric and a capping nitride layer. The second photoresist layer pattern is removed. A bit line contact plug, a metal wiring contact plug, and a storage electrode contact plug are formed. A second interlayer dielectric(42) is formed on the upper portion of the whole surface. A bit line(44) is formed to be connected to the bit line contact plug. A third interlayer dielectric(50) is formed the upper portion of the whole surface. A metal wiring contact hole(52a,52b,52c) is formed by etching the third, the second, and the first interlayer dielectrics.
Patent KR-20000045663-A (KR)
Title: Super-multifiber cable and manufacturing method for manufacturing thereof
Inventor: JEON YONG HAN
IPC: G02B6/00
Filed: 1998-12-30
Abstract: PURPOSE: A super multi-fiber cable and a manufacturing method thereof are provided to increase an optical-fiber density in a multi-slot core of the cable by widening widths of grooves of the multi-slot core, inserting a ribbon-like loose tube in a central portion of the slot core and installing a tension means at a predetermined position of the cable. CONSTITUTION: A number of grooves(12) of a multi-slot core(10) of a super multi-fiber cable are formed spirally along its peripheral surface to have widths relatively wider than those of the prior art. 16-fiber ribbons(40) are inserted into the grooves(12) and a ribbon-like loose tube optical-fiber(20) is inserted into an axially-penetrated central hole(15) provided in the relatively larger central portion of a first layer(11) of the multi-slot core(10), thereby increasing an optical-fiber density. In a number of inserting holes(13) of the first layer(11) between the grooves(12), a number of tension lines(30) made of steel cords are inserted to cope with outer tensional force. The inserting holes(13) are communicated with the outside by cut-away grooves(14) to facilitate the insertion of the tension lines(30).
Patent KR-19990036334-A (KR)
Title: 세라믹 필터 및 그 제조방법
IPC: H01P1/203
Filed: 1997-05-13
Abstract: 본 출원은 세라믹 필터 뿐만 아니라 그 제조방법을 서술한다. 이러한 필터는 필터의 작동중에 전자기적으로 결합되며 세라믹 유전체에 의해 분리되는 인쇄 금속층의 형태인 스트립라인 공진기를 두 개 이상 구비한다. 본 발명에 따르면, 금속층(바람직하게는 팔라듐의 금속층)은 최소 10 마이크로미터의 두께를 가져야만 하며, 단면 형상이 실질적으로 장방형이다. 이 특징을 갖는 필터는 작동중에 대단히 낮은 삽입 손실을 보인다. 본 발명은 소위 브로드라인-결합(broadline-coupling) 필터에 매우 효과적으로 사용될 수 있다.
Patent KR-19990044314-A (KR)
IPC: D21F3/02
Filed: 1996-09-24
Abstract: A top roll lifting arrangement for a roll press in a press section of a papermaking or boardmaking machine where the roll press includes a top roll and a bottom roll, the rolls being opposed and parallel and having main axes defining a press plane and forming between them a press nip. The press has a framework including two side frames in parallel relationship to each other, one located on the drive side of the machine and the other one on the tender side of the machine. Each side frame has a first vertical column upstream of the press nip and a second vertical column downstream of the press nip. The upper roll is carried by a brackets extending between the upstream and downstream vertical columns. The brackets have bevelled ends that co-operate with inclined surfaces of plate members on the vertical columns.
Patent KR-19990044579-A (KR)
IPC: A63B71/06
Filed: 1996-09-18
Abstract: A method and a facility for playing a game with a golf club and golf balls, the facility comprising: a site having a range area visibly divided into a plurality of contiguous target regions, each said target region being associated with a target identifier, and a tee area having a plurality of contiguous tees from which golf balls may be hit toward said range area; scoring means located at said site for scoring a game, said scoring means setting out a sequence of said target identifiers so as to establish a corresponding sequence of designated target regions to which golf balls are to be hit from the tee with a golf club in order, and said scoring means providing means for recording a point score for each time a player hits a golf ball; and a scoring system associated with said scoring means for awarding a point score according to the observed resting position of the golf ball relative to the designated target region.
Patent KR-19990077035-A (KR)
Title: 압력 감지성 잉크 수단, 및 사용 방법
IPC: G01L1/20
Filed: 1996-12-11
Abstract: 압력 감지성 잉크는 압력 감지성 장치의 압력 감지성 성분으로서 사용하기 위하여 설계된 선택적 압력 감지성을 갖는다.  장치의 잉크는 탄성의 중합체 결합제와 결합제에 바람직하게는 균일하게 분산된 반도성 나노입자의 충전제로 형성되어 있다.
Patent KR-20000064513-A (KR)
IPC: B01J23/02
Filed: 1997-03-14
Abstract: Propylene is oxidized to propylene oxide in the vapor phase using an oxygen-containing gas and a supported silver catalyst comprising silver and a support comprised in whole or in substantial part of certain alkaline earth metal compounds. The alkaline earth metal compound may, for example, be a calcium compound such as calcium titanate, tribasic calcium phosphate, calcium molybdate, or calcium fluoride, a magnesium compound such as magnesium aluminate, or a strontium compound such as strontium titanate. Such supports provide significantly higher selectivity to the desired epoxide than would be expected from the performance of related materials. Propylene oxide selectivity may be further enhanced through the introduction of nitrogen oxide species such as NO, alkyl halides such as ethyl chloride, and carbon dioxide into the oxygen-containing gas.
Patent KR-19990077237-A (KR)
Title: 플라즈마 처리장치의 세정방법 및 플라즈마 처리방법
IPC: C23C16/44
Filed: 1997-11-13
Abstract: 진공용기의 내부에 부착된 불소를 함유하는 카본막의 세정에 요하는 시간을 단축하고, 또한 세정의 경우에 재치대의 표면을 보호하는 것. 
     예컨대, 플라즈마 처리장치에서 CF막을 성막한 후에, 세정가스로서 O 2 가스를 진공용기(2) 내에 도입하고, 진공용기(2)의 내부에 부착된 CF막의 세정을 행한다.  세정에서는 O 2 가스를 플라즈마화 하고, 플라즈마에 의해 생긴 O의 활성종에 의해 CF막의 표면을 물리적, 화학적으로 C-C결합이나 C-F결합을 절단한다.   O 2 가스는 절단된 곳으로부터 CF막의 내부로 들어가고, CF막의 C와 반응하여 CO 2 를 생성하여 비산해 간다.   한편, F는 F 2 로서 비산해 가고, 이렇게 하여 CF막이 제거된다.
Patent KR-19990082412-A (KR)
Title: 활성 유체 물질 증발 장치
IPC: A01M1/20
Filed: 1996-02-09
Abstract: 본 발명은 액체 활성 물질 증발 장치에 관한 것이다. 상기 장치는 액체 활성 물질(12)에 담겨 있어 이 활성 물질을 운반하는 심지(7)를 포함한다. 액체 활성 물질(12) 밖으로 튀어나온 심지의 한쪽 끝 부분에 가열 장치(3)가 형성되어 있다. 상기 장치에는 액체 활성 물질(12)이 적어도 심지가 액체 물질(12)에 담겨 있는 길이 방향의 외부 표면을 통과하지 못하고, 심지(7)의 액체 밖으로 튀어나온 부분에 반대되는 부분의 밑면 영역(10)으로 액체 활성 물질(12)이 통과할 수 있도록 심지가 형성되어 있다. 또한, 증발하는 활성 물질(12)은 심지가 가열될 때 상기 가열 장치(3)를 통해 통과한다. 따라서, 액체 활성 물질이 균일하게 심지로 상승하게 된다.
Patent KR-19990087758-A (KR)
Title: 엔도쎌린 활성의 길항작용
Filed: 1997-03-13
Abstract: 급성 NO 합성효소 차단에 이은 고혈압 기구는 엔도쎌린-배개성 혈관수축을 경유한다. 따라서, NO는 엔도쎌린의 발현을 차단함으로써 엔도쎌린 활성을 억제해주는 것으로 여겨진다. "정상적인" 생리적 상태의 환자에게 엔도쎌린 안타고니스트를 투여하면 특정 신체부위에서 혈관확장이 일어날 수 있다. 이러한 처치는 발기부전의 치료에 이용될 수 있다.
Patent KR-20000016254-A (KR)
Title: Sterically hindered 4-amino-piperidine with a low dimer content, its production and use
Inventor: JULIUS MANFRED
IPC: C07B63/04
Filed: 1997-05-28
Abstract: PURPOSE: A process for reducing the dimerization of piperidine is provided which gives a simple method for preparing 4-amino-piperidine at a low cost of production and can manufacture HALS compounds having a low content of a by-product. CONSTITUTION: A process for reducing the dimerization of piperidine of formula (I) in which R1 to R4 are C1 to C6 alkyl, R1 and R2 and/or R3 and R4 together are a CH2 chain with 2 to 5 C atoms is described. The process is characterized in that to the piperidine is added 0.001 to 0.2 wt % of a reducing agent of the formula MXH4-mYm, in which M is an alkaline metal, NR4, where R is the same or different C1-4 alkyl groups, or an equivalent of an alkaline earth metal or an equivalent zinc, X is boron or aluminium, Y is H or CN and m is 0 or 1. Also described is a mixture of piperidine (I), 0.001 to 0.2 wt % of a reducing agent and 1 to 1000 ppm of the dimer of the piperidine (I), and the production of HALS stabilizers therefrom.