baber/WOPTO huggingface dataset:
Patent CN-1067880-A (CN)
Inventor: BVIJS WIM
IPC: C07B61/00
Filed: 1992-06-12
Abstract: 公开了酚的制法，它在含Cu(I)催化剂存在
下，在相应的芳基羧酸的液相中通过氧化脱羧来进
行，其中氧化脱羧在191—270℃下、在有水存在下进
行，所加入的氧量使一定量的铜保持以Cu(I)存
在，后者使对酚的选择性大于92％(在1巴下测定)，
使酚分离出来。该氧化脱羧反应优选通过下列步骤
进行：a)在191—240℃下氧化催化剂至多20分钟，
所加入的氧量使至少0.04wt％的铜保持以Cu(I)
存在；b)在无氧有水存在下，在210—270℃下，步骤
a)被氧化的催化剂进行反应并生成酚。
Patent CN-1088137-A (CN)
Inventor: YUNCHUAN ZHANG
IPC: B21B35/12
Filed: 1992-12-18
Abstract: 一种轧机主传动机构，提供一种分配扭矩，输出
扭矩可在轴线垂直平面内，沿任意规定方向平行分离
或靠拢，扭矩传递过程全部平行的轧机主传动机构，
由一个齿轮连杆组合机构实现，输出机构可以是滑块
铰点上齿轮，也可以是平行四边形机构，可代替人字
齿轮机座和万向接轴，满足普通轧机既要轧制，又要
上辊调开口度，下辊重磨后调标高的需要。
Patent CN-1129264-A (CN)
Title: 聚酯异纤度异断面混纤丝的制程改良
Inventor: ZHENLING LIN
IPC: D01D5/12
Filed: 1995-09-12
Abstract: 本发明利用同一喷丝板中具有不同的多种断面的喷丝口及直接延伸设备生产卷速高于3000m/min的聚酯异纤度异断面混纤丝，由提高纺丝温度、延伸受热时间及适度控制延伸、卷取张力，并选择摩擦系数较高的油剂着手，解决异纤度异断面混纤原丝有破丝及染斑的问题。 
     本发明制得的直接纺丝延伸原丝于染整后，可使布面具有高度的蓬松层次感、干涩清凉感。
Patent CN-1137804-A (CN)
Title: 可贴合的隔离带
Inventor: TODDY J N
IPC: C09J7/21
Filed: 1995-01-04
Abstract: 本发明提供了一种噪声控制的方法，该方法是将由可伸长的材幅和粘合剂制成的合适的片材料插入部件之间，使由部件产生的噪声得以防止，降低或消除，本发明也提供了一种适合于该方法使用的合适的片材料。
Patent CN-1174524-A (CN)
Inventor: LEONARD WILLIAM K
IPC: B05D1/30
Filed: 1995-12-11
Abstract: 用多层涂层涂覆基底(32、102)的方法,包括使基底沿一路线移动通过具有涂层模(10、110)的涂层工位。用第一和第二涂层流体(34、36、104、86)形成一复合层(48、118)。基底(32、102)与流动的复合层相接触,使第一涂层流体(34、104)夹于基底(32、102)和第二涂层(36、86)之间。用从一气体刮刀(54、124)喷出的气体(52、122)来修刮复合层,以从基底上除去该复合层的一些部分。
Patent CN-1164030-A (CN)
Inventor: SCHMID STEFFEN
IPC: G02B6/10
Filed: 1996-08-02
Abstract: 一种具有偏振无关响应的可调声光波导器件，它包含一个双折射光弹性材料的衬底(1)，其上有光信号二个分离偏振分量的至少一个偏振模转换级(20)、分别位于转换组(20)上游和下游的一个第一和一个第二偏振选择元件(18、19)、以及至少一个偏振模转换的补偿级(10；100)，其中至少一个光波导(11；110)以组合形式传送二个偏振分量。一种光信号声光转换的方法，基于利用同二个声波的声光相互作用分别对传送的分离和未分离的光信号偏振分量的二种转换。
Patent CN-1256842-A (CN)
Title: 用于整理来自多个源的数据以形成用于显示的复合节目指引的系统
Inventor: WEHMEYER K R
IPC: F24S23/70
Filed: 1997-09-23
Abstract: 一种视频解码器系统,用于整理从各种本地源和远程源(405,415,420)获得的节目引导信息。从第一源接收节目引导信息并且可以显示可选的节目引导菜单光标。根据菜单光标的选择,通过显示属性整理(425)来自第一源的节目引导信息条目的分类,并且显示所整理出来的节目引导信息条目。分配给节目引导信息条目的分类的显示属性对条目和菜单光标的分类是公用的。利用对节目分类用的相等映射信息,根据主组的节目分类(425)将标识节目分类的码转换成其它码。复合节目映射信息可包括用在对第二源(420)的条目的检索中的分配给节目引导信息条目的新数据。
Patent CN-1249780-A (CN)
Title: Fas受体功能的调节剂－有死亡效应结构域的cash(卡斯酶同系物)
Inventor: WALLACH D
IPC: C12N1/19
Filed: 1998-02-26
Abstract: 本发明公开了能调节或介导MORT－1功能的蛋白质。还公开了编码这些蛋白质的DNA序列,重组产生这些蛋白的方法以及它们的用途。
Patent CN-1242661-A (CN)
Title: 移动式电话机
Inventor: YOSHIO SAITO
IPC: H04M1/02
Filed: 1999-07-02
Abstract: 本发明的移动式电话机,由于将接收和发送信号元件6的框体7的一部分,放置在母基板4和电池9之间,将框体7安装在母基板4上,因此,可以有效地利用母基板4和电池9之间的空间,空间因素良好,可以提供小型的移动式电话机。
Patent CR-20150366-A (CR)
Title: Métodos para incrementar el rendimiento de los cultivos
Inventor: MALEFYT TIMOTHY
IPC: A01N25/00
Filed: 2015-07-09
Abstract: La invención se basa en un efecto más que aditivo inesperado de múltiples aplicaciones de al menos ciclopropeno en el rendimiento de cultivos en comparación con aplicaciones únicas.
Patent CR-20170076-A (CR)
Title: Derivados de pirimidima sustituidos con heterociclilo opcionalmente condensados útiles para el tratamiento de enfermedades inflamatorias, metabólicas, oncológicas y autoinmunitarias
Inventor: HAAHR GOULIAEV ALEX;
IPC: C07D487/04
Filed: 2015-07-31
Abstract: Se divulgan compuestos activos frente a receptores nucleares, composiciones farmacéuticas que contienen los compuestos, y el uso de los compuestos en tratamiento.
Patent CR-20170594-A (CR)
Title: Moduladores de receptor nuclear
Inventor: KORT MICHAEL E
IPC: C07D491/10
Filed: 2016-06-08
Abstract: La invención proporciona compuestos de Fórmula (I), sales farmacéuticamente aceptables de los mismos, en la que la variable se define en el presente documento. Los compuestos de la invención son útiles para tratar afecciones inmunológicas
Patent CR-20190100-A (CR)
Title: Substituted pyrrolizine compounds and uses thereof
Inventor: LAZERWITH SCOTT E
IPC: C07D519/00
Filed: 2017-08-25
Abstract: This application relates to substituted fused pyrrole compounds of formula I, and pharmaceutical compositions comprising them which inhibit HBV replication, and methods of making and using them. Formula (I)Esta solicitud se refiere en general a ciertos compuestos de pirrolizina sustituidos, y a composiciones farmacéuticas que inhiben la replicación de HBV, y a métodos para fabricarlas y usarlas
Patent CR-20190568-A (CR)
Title: A synergistic agricultural formula comprising diacyl or diaryl urea and at least one plant growth regulator
Inventor: SHETH RITESH
IPC: C05F11/10
Filed: 2018-07-02
Abstract: A synergistic agricultural formula including at least one diacyl or diaryl urea, such as a ¿,¿'-diformylurea, and at least one plant growth regulator. This synergistic agricultural formula gives those skilled in the art the ability to regulate important phenotypical parameters that lead to a variety of important agronomic and horticulture traits which improve crop yield parameters leading beyond that of its individual components.
Patent CR-20200168-A (CR)
Title: Bicyclic sulfones and sulfoxides and methods of use thereof
Inventor: HAMILTON GREGORY
IPC: C07D249/16
Filed: 2018-10-30
Abstract: Provided are compounds having the general formula I: wherein R1, R B1, RB2, n, p, q, the A ring and the B ring are as described herein, pharmaceutical compositions including the compounds, and methods of using the compounds. The compounds of formula (I) are inhibitors of RIP1 kinase and thus useful in the treatmemt of inflammatory, neurodegenerative and other disorders.
Patent EC-SP066319-A (EC)
Title: Metodo para extraer aceite del fruto de la palma y aparato para esterilizarlo
Inventor: CHOONG HWA DOONG
IPC: A23L3/16
Filed: 2006-01-26
Abstract: Se proporciona un método para extraer aceite del fruto de la palma de aceite que podría comprender: alimentar directamente los racimos de fruta dentro de un esterilizador vertical que esteriliza los racimos cargados de fruta con vapor y agua; y descargar directamente los racimos de fruta desde el esterilizador vertical a un transportador de racimo para el posterior procesamiento. La introducción de agua en el esterilizador podría ser para desplazar aire, lavar la fruta y amortiguar el impacto en la fruta durante el movimiento en el esterilizador. Un desplazamiento sistemático de aire, agua y condensado, utilizando medios mecánicos y el ingreso de vapor presurizado en el esterilizador, esteriliza la fruta. Preferiblemente, los medios mecánicos se podrían seleccionar de una bomba de vacío o al menos dos válvulas de entrada de vapor que operan en secuencia. Podría ser ventajoso utilizar un mecanismo de empuje de la fruta para evacuar la fruta esterilizada del esterilizador vertical. El procesamiento adicional, después de la descarga desde el esterilizador, comprende los procesos de separación, prensado o recuperación de grano.También se proporciona un aparato para esterilizar los racimos de fruta de la palma de aceite, el aparato podría comprender un contenedor con su altura mayor que su diámetro. El contenedor podría comprender: al menos una abertura de entrada para cargar racimos de fruta; al menos una abertura de salida para descargar los racimos de fruta; al menos una válvula de ventilación para la salida de vapor y agua del contenedor; al menos dos válvulas de entrada de vapor para la entrada de vapor al contenedor; al menos una válvula de escape para la salida de condensado del contenedor; al menos una válvula de agua para el control de entrada de agua dentro del contenedor; y al menos una válvula de ventilación de aire para permitir la ventilación de aire desde el contenedor. Preferiblemente, un desplazamiento sistemático de aire, agua y condensado, utilizando medios mecánicos e ingreso de vapor presurizado en el aparato, esteriliza la fruta. Los medios mecánicos podrían ser una bomba de vacío o al menos dos válvulas de entrada de vapor que operan en secuencia. Es preferible que el contenedor sea cilíndrico o invertido en forma cónica. Ventajosamente, el contenedor invertido en forma cónica permite que la fruta pase al contenedor y la pulpa no tenderá a formar puentes debido a la forma. Ventajosamente, el aparato además podría incluir una placa inclinada perforada que actúe como un tamiz. Podría ser ventajoso para el aparato incluir además un triturador arqueado. El aparato, preferiblemente, podría incluir además un mecanismo de empuje de la fruta.
Patent EC-SP067077-A (EC)
Title: Derivados de pirrolopiridina y su uso como antagonistas de crth2
Inventor: BALA KAMLESH
IPC: C07D471/04
Filed: 2006-12-12
Abstract: De acuerdo con la invención, se proporcionan compuestos de Fórmula (I):en forma libre o de sal, donde R1, R2, R3, R4, R5, R6, Q, W, X, m, n y p son como se describen en la especificación, un proceso para su preparación, y su uso como productos farmacéuticos.
Patent EC-SP077976-A (EC)
Title: Formulaciones de quinina
Inventor: DU JIE
IPC: G16H20/10
Filed: 2007-11-30
Abstract: En la presente se divulgan formulaciones de quinina de liberación controlada y métodos para la preparación de las mismas. También se revelan métodos para prevenir o tratar la malaria, calambres de las piernas, o la babesiosis mediante la administración de formulaciones de quinina de liberación controlada. Las formulaciones de quinina de liberación controlada pueden ayudar a reducir o eliminar los efectos colaterales adversos típicamente asociados con la dosificación de quinina.
Patent EC-SP088592-A (EC)
Title: Compuestos dímeros agonistas de los receptores de los fgf (fgfr)
Inventor: OLSEN JACOB ALSBOEK
IPC: C07D519/00
Filed: 2008-07-01
Abstract: Compuestos agonistas de los receptores FGF que responden a la fórmula general: M1-L-M2 en la que M1 o M2 idénticos o diferentes representan cada uno independientemente el uno del otro una unidad monómera M y L representa un grupo de unión que une M1 y M2 de manera covalente, con dicha unidad monómera que responde a la fórmula general M siguiente: (I). Proceso de preparación y aplicación en terapéutica.
Patent EC-SP088706-A (EC)
Title: Antagonistas de receptor de factor de crecimiento de tipo insulina (igf-ir) como auxiliares para tratamiento de cáncer de próstata
Inventor: LUDWIG DALE
IPC: A61K38/00
Filed: 2008-08-28
Abstract: La presente invención se refiere a un método para tratar cáncer de próstata con terapia de privación de andrógeno y un antagonista de receptor de factor de crecimiento de tipo insulina (IGF-IR). Aunque la velocidad de respuesta de cáncer de próstata a la terapia de privación de andrógeno (ADT) es alta, las células de cáncer que sobreviven invariablemente se vuelven independientes de andrógeno (AI) y sigue el crecimiento del tumor. La invención inhibe o retrasa la transición de cáncer dependiente de andrógeno a cáncer independiente de andrógeno, significativamente reduce el riesgo de recurrencia, y mejora el resultado del tratamiento.
Patent FI-20125975-A (FI)
Inventor: ERIKSSON LASSE
IPC: G01C9/00
Filed: 2012-09-20
Abstract: To facilitate the use of a crane, an angle feedback information on a rope angle (theta)of the crane is received, the angle feedback information being measured by means of a sensor at or adjacent to a trolley; and the angle feedback information is corrected by compensating an error caused by a speed change, and processed to provide movement instructions or other control information relating to the crane on the basis of real-time corrected angle information.
Patent FR-1587512-A (FR)
IPC: E05F3/12
Filed: 1968-10-15
Granted: 1970-03-20
Abstract: 1,221,449. Door closer with resilient throttle mounting. DORKEN & MANKEL K.G. 30 Oct., 1968 [4 Nov., 1967], No. 51467/68. Heading E2M. . In an automatic door closer of the type employing spring closing and hydraulic damping, the damping device includes an annular seating member 17 spring-loaded against the end wall 15 of the chamber of the working cylinder 10, a pin 21 co-operating with the annular member 17 to define a throttle opening for controlling the flow of damping medium, and an adjusting screw 24 with a conical portion 23 to displace the pin 21 axially relative to the seating member 17 to vary the throttle opening, the spring-loading being such that if the pin 21 is pushed in too far it will lift the seating member 17 from its normal position. During the door closing movement the piston 11 moves to the right against the force of the spring 12 bearing against the seating member 17, which is partially slidably carried in a bore 14 in the end wall 15, and the damping medium flows under pressure through the passage 18 and the throttle opening and past flats 22 cut on the surface of the pin 21. At least the pin 21 is preferably made of plastics material having a high coefficient of heat expansion to compensate for variations in viscosity of the damping medium.
Patent FR-1603179-A (FR)
Title: Fish filleter
IPC: A22C25/16
Filed: 1968-07-30
Granted: 1971-03-22
Abstract: Fish filleter handles all sizes and comprises a flat, veed table with groove for the upper belly and back fins and an inverted vee cover leading to two double-cone wheels to run each fish under a fork. Two paired sets of knives make four lengthways incisions either side of the backbone so that top and bottom chains engage these slits and another set of knives can lower down between the chains in between lower saw blades provided. The top cover acts as a switch to lower the upper knives, and spiked rollers help to feed the fish to the conveyor chains by driving their spikes between the vertebrae of the spine. As the chains run down to the lower guide they help to draw the flesh away from the spine. The outer ends of the tips of these two chains lie spaced to admit the vertebrae between and draw these downwards. The chains are angled so that the rims fo the fillets bear on the top guides, thus easing the backbones clear to drop into an offtake channel.
Patent GB-1050152-A (GB)
IPC: G10H1/057
Abstract: 1,050,152. Electrophonic organs. BURGE ELECTRONICS Ltd. Dec. 12, 1962 [Sept. 15.. 1961], No. 33122/61. Heading G5J: Oscillations corresponding to a note 1 are fed over a potentiometer 20 and diodes 21, 12 to a bus-bar 15. The diodes are normally biased to cut-off by positive battery on resistor 13. As shown, pairs of diodes 21, 12 are enabled to pass notes 1 to 5 to corresponding bus-bars 15 by negative bias connected over a common time constant circuit 18, 16 by a single key contact pair 11. Condenser 16 and the associated resistors control attack and decay for all the notes controlled by the single key. Fig. 2 shows a keying circuit A in the swell organ and leads to similar circuits B, C in the great organ and D in the pedal organ all the circuits corresponding to a single note. In the swell organ, C is an octave above B. The corresponding keys in the swell, great and pedal organs operate contacts 11, 11a to 11c and 11d to 11f. Normally only contacts 11, 11a, 11d are operative but the others can be brought into use by operation of coupler contacts 29 to 32. In Fig. 3 (not shown), bus-bar 37 is connected to a different diode 38 for each stop and controls sforzando. For crescendo switches 36, 39 &c. are closed in sequence to bring in a succession of stops. Each bus-bar 40, 41 &c. is connected to a different stop or group of stops. The key contacts 11 may be arranged between positive bias and resistor 13. The contacts are normally closed and resistor 18 is connected to negative keying potential.
Patent GB-1050418-A (GB)
IPC: G21G4/06
Abstract: 1,050,418. Radioactive materials. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. May 28, 1965 [June 17, 1964], No. 25002/64. Heading G6R. A soluble low-activity radioactive source comprises a tablet of soluble inactive carrier having on one surface -thereof a low-activity deposit of a soluble compound containing a radioactive isotope. In Example 1, tablets of inactive KI are treated with one drop each of an aqueous solution of NaI containing 1-131, and then dried under an infra-red lamp. In: Example 2, tablets of inactive sodium orthophosphate are similarly treated with an aqueous solution of the same salt containing P-32. Reference is made also to depositing sodium chloride, carbonate, or bicarbonate containing N1-22 on an inactive tablet of the same salt. The tablets are used to prepare solutions of known radioactivity by dissolving in water or other solvent.
Patent GB-1050549-A (GB)
IPC: A23G3/04
Abstract: 1,050,549. Sugar confectionery; caramel. SOC. ANON. LA PIE QUI CHANTE. March 6, 1964 [March 18, 1963], No. 9555/65. Heading A2B. In the continuous processing of ingredients for the manufacture of sugar based confectionery, a sugar-containing syrup-like mixture in the form of a thin layer is subjected to a rapid rise in temperature over a limited period to avoid inversion, browning and crystallization, the while subjecting the layer to a vigorous stirring action, thereby eliminating water, subjecting the mixture to cooling, adding further ingredients to the mixture during the cooling if required and then passing the mixture for further manipulation. Thus, the syrup may be passed through the narrow annular space between an outer heated cylinder and an inner rotating surface having a helical rib on its periphery, such that the mixture is brought from 70‹-90‹C. to the treatment temperature in not more than one second. The cooling may be effected in the same vessel, by having a portion of the wall cooled, or in a second similar vessel. Preferably the mixture traverses the cooling zone more slowly than the heating zone and the heating zone may have vented recesses in its upper portion for the escape of water vapour. The process is useful for the preparation of boiled sugar, caramel, and toffee products.
Patent GB-1051752-A (GB)
IPC: H02M5/00
Abstract: 1,051,752. Frequency changing. ENGLISH ELECTRIC CO. Ltd. Sept. 18, 1963 [Sept. 22. 1962], No. 36117/62. Heading H2F. [Also in Division G3] In an automatic control system for regulating the output voltage from a controlled rectifier frequency converter, signals are derived from each phase of the output voltage which is compared with the rectifier grid control voltages and the difference applied to the rectifier grids to maintain the output voltage constant. Signals derived from a, symmetrical earthed resistance network R1-R3 are smoothed by circuits 11-13 and compared with the grid control voltages before being passed through amplifiers 14-16 to the rectifier grids. The resistance network may be replaced by magnetic amplifiers, the control current of which is derived from the output voltage.
Patent GB-1052891-A (GB)
IPC: E04B1/78
Abstract: 1,052,891. Strengthening edges of sheet material. OWENS-CORNING FIBERGLAS CORPORATION. March 13, 1964, No. 10757/64. Heading B5K. [Also in Divisions E1 and F4] An insulating stud for use in insulating a floor, wall or ceiling of, e.g. a cold storage room, comprises a web formed from one or more lengths of a fibrous, heat insulating material, e.g. glass wool board, bonded along each edge to a basically channel-sectioned capping member of, e.g. extruded aluminium. The capping member may be of simple channel section, or of top-hat or #-section, and the method of bonding to the web comprises dipping the respective web edge in hot asphalt, draining briefly, inverting dipped edge, inserting dipped edge into channel of capping member, repeating steps for the other capping member, clamping the three members together, re-heating to cause the asphalt to flow again and finally cooling the stud to cause the asphalt to bond the web to the capping members.
Patent GB-1225085-A (GB)
IPC: H01Q5/49
Filed: 1969-07-28
Abstract: 1,225,085. Aerials. ROHDE & SCHWARZ. 28 July, 1969 [8 Oct., 1968], No. 37759/69. Heading H4A. In an aerial of the backfire type, comprising an end-fire array having a main reflector at one end and an auxiliary reflector at the other end, one or more active elements are incorporated directly in said end-fire array. As described, an aerial comprises a flat surface main reflector 1, Fig. 2, and an auxiliary reflector 2 formed, for example, by individual rods or by a circular metal disc, and at a distance L 2  from the reflector 1, which provides resonance at the lower end of the operating frequency band. A feed dipole 4 is near the main reflector 1, and incorporates an active element 5, such as an amplifying transistor. Between the dipole 4 and the auxiliary reflector 2 are director elements 3 and an additional element 6, next to the reflector 2, which incorporates an electronically controllable active element 7, such as a diode or a transistor. The element 6 is at a distance L 1  from the reflector 1 and when it is made fully reflective by suitable adjustment of the voltage upon the active element 7, it provides resonance at the upper end of the operating frequency band. For other voltages upon the active element 7, the element 6 is partially reflective, and resonance is obtained at intermediate frequencies within the operating frequency band. In another embodiment, a feed dipole (4), Fig. 1 (not shown), incorporating an active element (5), is placed near an auxiliary reflector (2), and the aerial further comprises only director elements (3) and a main reflector (1).
Patent GB-1225207-A (GB)
IPC: F16K11/085
Filed: 1969-04-17
Abstract: 1,225,207. Valves. H. J. AIROLA, and P. J. PELTOLA. 17 April, 1969 [26 April, 1968], No. 19599/69. Heading F2V. [Also in Division G3] A bi-metal spiral for operating a three or four way distribution valve in say a central heating system is situated in a closed housing and is heated by a lamp 16 which gives more rapid response than previously used heaters. The spiral may have a blacked surface and the interior surface of the housing may be treated to increase thermal radiation. An arcuate adjustable transparent member 10-12 may set the operating point of the valve and allow the operation of the lamp to be observed. A flexible member (19, 20), Fig. 4 (not shown), may allow some misalignment. The valve may be used in a central heating system comprising a boiler controlled by inlet water temperature, a pump 2 and valve 3 controlled by temperature measured at 6 forming a primary circulation system, and a secondary circulation system including a valve 4 controlled by a room thermostat T, radiators or other heating load 5, and pump I. It is stated that the electric lamp, normally of 20-25 watts consumption is more easily replaceable then previously used resistance heaters.
Patent GB-1227201-A (GB)
IPC: G03C5/08
Filed: 1968-02-20
Abstract: 1,227,201. Fraud preventing. LITTON BUSINESS SYSTEMS Inc. 20 Feb., 1968 [20 Feb., 1967], No. 5196/68. Heading B6A. [Also in Divisions C4 and D2] To prevent unauthorized reproduction of printed data a sheet bearing permanent data comprises photochromic material, the data having the same colour as that of the material in excited state. The photochromic material is incorporated in or coated on paper. Examples of the material are phosphotunstic acid and a binder of polyvinyl butyral in ethyl alcohol; silico- and phospho-tungstie acids glycerine and an aqueous acetate acrylic copolymer emulsion and #-tetrachlorketonaphthalene in methyl ethyl ketone. Other photochromic materials are CuCl 2 , benzyldihydraphenol, hydrazine, spiropyrans, bilophenes and triarylmethaneleucocyanides. The material is applied by roller, brush or spray. In electrophotographic copying apparatus photochromic paper 11 carrying data passes between rollers 12, 13 under a flashing light source 19, e.g. a gas filled tetrode and a projector 6 which produces an image of paper 11 on paper 2 coated with a photoconductive composition charged by device 4. The image is developed by passing the paper 2 through a cascade of fusible resin particles and tiny glass carrier beads and over a heating drum 17. The paper 11 is excited by source 19 thereby rendering the data indistinguishable and preventing reproduction. After passing through the apparatus the paper is kept in the dark and thereby reverts to its original state. The apparatus forms the subject matter of Patent (Application No. 49831/70).