baber/WOPTO huggingface dataset:
Patent GB-913803-A (GB)
Title: Vacuum seal for high power microwave tubes
IPC: H01J23/36
Filed: 1959-12-18
Abstract: 913,803. Discharge tubes. CSF COMPAGNIE GENERALE DE TELEGRAPHIE SANS FIL. Dec. 18, 1959 [Jan. 5, 1959], No. 43022/59. Class 39 (1). [Also in Group XL (b)] A high-power microwave vacuum discharge tube provided with an output wave-guide has a seal incorporating two wave-guide portions 2, 3 and a window 1 of insulating material, wherein the extremity of each waveguide portion adjacent the window is bent, e.g. by crimping, at 4 and 5, Fig. 1, and 8 and 9, Fig. 2, to form a frame having a rounded inner surface, the window 1 being brazed at 6 to the frames. The window 1 can be of ceramic, alumina, glass or quartz.
Patent GB-1125628-A (GB)
Title: Xerographic development apparatus
IPC: G03G15/10
Filed: 1965-10-11
Abstract: 1,125,628. Developing electrostatic images. RANK XEROX Ltd. Oct.11, 1965 [Oct.28, 1964], No. 43040/65. Heading G2H. Latent electrostatic images are developed with toner suspended in a carrier liquid by causing the developer to flow over ridges 11, Fig.1, to create waves adjacent the surface 13 (17) Fig. 2 (not shown), carrying the image. The developer is agitated by air supplied by pump 1, Fig. 1, and is circulated by a pump 7.
Patent GB-1008484-A (GB)
Title: Drive mechanism for electric contact make and break devices
IPC: H01H3/26
Filed: 1963-11-01
Abstract: 1,008,484. Electromagnetic switches. A. J. L. CROMPTON. Nov. 1, 1963, No. 43200/63. Heading H2B. A switch drive mechanism as described in Specification 881,803 operates a cam 18 acting on a contact spring set 19 as well as or instead of the rotary contact arm. Specification 970,806 also is referred to.
Patent GB-918966-A (GB)
Title: Improvements in the production of acetic anhydride and acetic acid
IPC: B01J19/24
Filed: 1960-12-16
Abstract: <PICT:0918966/IV (b)/1> Acetic anhydride and acetic acid are made by the oxidation of acetaldehyde in a reactor containing a liquid reaction bath essentially consisting of a mixture of acetic anhydride and acetic acid containing an aldehyde oxidation catalyst comprising at least one metal acetate, the reaction products being entrained from the reaction bath by the oxygen-containing gaseous mixture passed through said bath, and the acetaldehyde being introduced in liquid phase into the gas cycle at a point between the gas outlet of the reaction vessel and the residual gas discarding point, so that said acetaldehyde vaporizes at the expense of the heat carried by the gaseous stream thus cooling said gaseous stream. The liquid acetaldehyde is preferably introduced in droplet form and may be sprayed within a zone traversed by the gaseous stream and/or this zone may contain devices adapted to break up the liquid stream.  In particular the liquid acetaldehyde may be fed to the top of a tower which is upwardly traversed by the gaseous stream.  In the drawing, oxygen-containing gas laden with acetaldehyde vapour is introduced at 3 and fed through porous plate 1a into the liquid reaction bath in reactor 1 and the gaseous stream from 1 passes through condenser 6 to saturator 7 filled with Raschig rings and fed at its top with liquid acetaldehyde via pipe 2.  The liquid mixture of reaction products and acetaldehyde from 6a and 7a is fed to a distillation unit. Part of the gaseous stream is removed at 9 and washed and distilled to recover acetaldehyde.  The mixture of fresh oxygen-containing gas introduced at 10 and the remaining acetaldehyde-containing gaseous stream is sent to the reactor by fan 11 via pipe 3.  The process may be combined with the use of a dephlegmator from which condensate is refluxed to the reaction bath to maintain constant volume as described in Specification 910,861.  It is also possible to mix only a part of the acetaldehyde with the gaseous stream, the remainder being introduced in liquid phase directly into the reactor.
Patent GB-1488695-A (GB)
Title: Epoxy resin composition
IPC: H01B3/40
Filed: 1974-10-08
Abstract: 1488695 Epoxy resin composition KUREHA KAGAKU KOGYO KK 8 Oct 1974 [9 Oct 1973 (2)] 43600/74 Heading C3B A composition comprises an epoxy resin and at least one fluoranthene or pyrene of formula in which R is C 1-4  alkyl, x=0-4 and when x>2 each R may be the same or different. From 2-100 parts by wt. of I and/or II may be present per 100 parts of epoxy resin. I and/or II may be present as mixtures of isomers. Uses.-Electrical insulation.
Patent GB-1508876-A (GB)
Title: Manufacturing aluminium by molten salt electrolysis of aluminium oxide
IPC: C25C3/12
Filed: 1975-10-23
Abstract: Aluminium oxide is dissolved in a salt melt. The melt contains aluminium sodium fluoride as the main constituent. Arranged in the melt there are an anode and a cathode. Between the anode and the cathode there flows direct current. As a result, the aluminium oxide is electrolysed. Part of the anode or the cathode comes into contact with the salt melt. At least this part is made of an electron-conducting composition or covered with an electron-conducting composition. The composition contains at least 50% by weight of at least one electron-conductive, ceramic oxide material. The oxide material corresponds to the formula:     1. XYO2   2. X2Y2O7   3. XYO4   4. <IMAGE>     5. AxOy.Ta2O5   6. AxOy.Nb2O5   In the formulae, A, Ai, Bj, XAi, XBj, i, j, k, l, X, Y, x and y have the meanings specified in claim 1. The anode or cathode, respectively, does not react with oxygen and is chemically resistant to the melt.
Patent GB-1207840-A (GB)
Title: Racket frame and production methods therefor
Inventor: TRYSINSKY STANLEY
IPC: A63B60/02
Filed: 1967-09-26
Abstract: 1,207,840. Games racket frames. S. TRYSINSKY. 26 Sept., 1967 [22 Nov., 1966], No. 43747/67. Heading A6D. A racket frame for tennis and like games comprises a head and a fitment for a handle moulded in one piece from monofilamentary material, e.g. glass fibres, bonded with a thermo-setting resin, e.g. a polyester or epoxy resin. A handle is affixed after moulding. Manufacturing details are given.
Patent GB-1505204-A (GB)
Title: Method for forming glass bottles
IPC: C03B9/16
Filed: 1976-10-22
Abstract: 1505204 Glass bottles OWENS-ILLINOIS Inc 22 Oct 1976 43876/76 Heading C1M Bottles with thin walls of uniform thickness are made by feeding a gob to a fixed inverted one-piece parison body mould having a split shoulder and neck moulds thereon; compacting the charge into the mould cavity; counter blowing against a baffle at the top of the mould; removing the baffle and body mould; blowing the parison whilst supported by the shoulder and neck moulds to give a parison of uniform wall thickness in the expanded portion; removing the shoulder mould, inverting the parison and removing the neck mould; enclosing the parison in a blow mould and allowing it to sag to less than half the height of the blow-mould; and then expanding the parison to its final form (e.g. by applying a vacuum to the mould cavity and optionally blowing through the neck).
Patent GB-1489251-A (GB)
Title: Air cargo container
IPC: B65D88/14
Filed: 1974-10-10
Abstract: 1489251 Container traffic ; securing containers in aircraft FRUEHAUF CORP 10 Oct 1974 [11 March 1974] 43914/74 Headings B8P and B8Q [Also in Division F2] A cargo container comprises extruded aluminium floor members 18 and side rails 33 of channel section having a securing flange 36 to which side panels 38 are riveted. One end wall is of similar construction, Fig. 3, and the other end has two hinged doors 120 fitted with seals 110. The top cover is formed of a sheet 70 supported by cross beams (not shown) and rails 97, 104 the latter having a rain gutter 103 above the doors. The side and end panels are reinforced with box section ribs, such as those shown at 96 on one end wall. The floor members are in several sections with overlapping flanges which allow some adjustment of the width of the container before the floor sections are finally welded together. The side rails 33 carry pairs of spaced anchoring blocks 150, 151 which receive latches for securing the container in position. A T-section track 40 is provided on both the upper and lower securing flanges 36 to facilitate securing the cargo within the container.
Patent GB-1368288-A (GB)
Title: Power tools
IPC: H02K7/14
Filed: 1971-09-21
Abstract: 1368288 Portable electric drills MCGRAW EDISON CO 21 Sept 1971 [6 Oct 1970] 43997/71 Addition to 1277518 Heading B3C The subject-matter of this Specification is the same as that described in Specification 1,277,518 with the addition of further methods of attaching the two plates together and fitting them in a tool housing. Figure 2 shows two plates riveted together but having out turned stiffening flanges 136 that engage in T-slots in webs of a tool housing. Figure 4 illustrates plates having complementary struck out eye portions and cut outs with rods 194 enaging through the eye portions to connect the plates together. Fig. 7 shows plates joined by C-clips 220 whilst Fig. 10 shows a plate 224 having turned back edge portions to clamp plate 220. Fig. 12 illustrates plates where the struck out bearing recesses are replaced by bearing blocks 240, 242 fixed between the plates via stub shafts 244.
Patent GB-1218225-A (GB)
Title: Screening apparatus
Inventor: HARRIS JOHN HENRY
IPC: B07B1/00
Filed: 1968-09-17
Abstract: 1,218,225. Wet screening apparatus. CONSOLIDATED TIN SMELTERS Ltd. 16 Sept., 1969 [17 Sept., 1968], No. 44054/68. Headings B1D and B2H. A screening apparatus suitable for a wet separating process comprises a downwardlyextending concave sheet of woven wire provided on its convex side with a downwardlysloping, transverse deflector which directs pulp away from the screen surface. The deflector may consist of two crimps in the sheet. The wire is of stainless steel. A feed box supplies a stream of pulp vertically downwards over the concave surface. A number of screens in series may be provided.
Patent GB-1027541-A (GB)
Title: Separation process and apparatus
IPC: C12H6/04
Filed: 1962-11-22
Abstract: 1,027,541. Centrifugal contacting of liquids. ESSO RESEARCH & ENGINEERING CO. Nov. 22, 1962 [Dec. 4,1961], No. 44239/62. Addition to 1,022,235. Headings B1F and B2P. Baffle means are provided in the disc stack centrifuge of the parent specification in the path of flow through the opening between the frustoconical dividing means 9 and the inner wall of the shell 14. Example are given in Figs. II to IV (not shown). The solid material in the liquids being centrifuged is coagulated by the baffles.
Patent GB-1510313-A (GB)
Title: Refractory tiles
IPC: B22D7/10
Filed: 1975-11-12
Abstract: 1510313 Moulding tiles RESIL PROCESSES Ltd 12 Nov 1975 [11 Oct 1974] 44243/74 Heading B5A [Also in Divisions C3 and B3] A tile for use in a hot top or feeder having a layer of a ceramic fibre composition comprising a ceramic refractory fibre, a high temperature binder and a low temperature binder and a backing layer therefor formed of a backing composition comprising 70-95% by weight of refractory aggregate, 2-12% by weight of fibrous organic material and 1-9% by weight of resin binder is prepared by forming an aqueous slurry of the ceramic fibre composition, introducing a layer of said slurry into a mould, lightly pressing the layer of ceramic fibre composition, introducing a slurry of backing composition the solids content of which comprises 70-95% by weight of refractory aggregate, 2-12% by weight of fibrous organic material and 1-9% by weight of resin binder to fill the mould, pressing the composition within the mould to express water from the mould in a direction substantially coaxial with the direction of pressing, removing the green shape from the mould and thereafter drying and/or curing the green shape at an elevated temperature. In a modification the backing composition is first applied to the mould following by the slurry of ceramic fibre composition. The high temperature binders are defined as retaining their bonding properties at temperatures around 1000‹ C., e.g. argillaceous material or colloidal silica, whilst the low temperature binders are usable only up to 150‹ C., e.g. a phenol formaldehyde resin or starch. Suitable tiles have a layer of ¢ inch of compacted ceramic fibre composition on a ¥ inch of backing composition. The specific example discloses the production of a tile the backing layer of which comprises paper, refractory aggregate, expanded fireclay, synthetic resin and sulphite lye and the ceramic fibre layer of which comprises ceramic refractory fibre, ball-clay and synthetic resin.
Patent GB-444819-A (GB)
IPC: C09B45/16
Filed: 1934-09-27
Abstract: Chromium compounds of azo dyes are made by treating with an agent yielding chromium a pyrazolone-azo dyestuff at the general formula <FORM:0444819/IV/1> in which R = aryl, R1 = C6H5 or COO--alkyl, R2 = an aryl radicle containing a carboxylic acid group in one o-position to the azo group and no hydroxy group in the other o-position to the azo group, and wherein at least one of the radicals R and R2 must contain at least one sulphonic acid group.  They dye wool, silk and leather in yellow to orange shades.  In examples: (1) the dyestuff anthranilic acid --> 1 - (2<1> : 5<1> - disulphophenyl) - 3 - phenyl - 5-pyrazolone is treated with chromium formate, and (2) the dyestuff anthranilic acid --> 1-(2<1>-sulphophenyl) - 3 - phenyl - 5 - pyrazolone with chromium fluoride, (3)--(7) the following dyestuffs are similarly chromed : 2-amino-3-chloro-5-sulphobenzoic acid --> 1-(2<1>-phenoxy-5-sulphophenyl) - 3 - phenyl - 5 - pyrazolone, anthranilic acid --> 1-(2<1> : 4<1>-disulphophenyl)-5 - pyrazolone - 3 - carboxylic acid ethyl ester, 2-amino-3-chloro-5-sulpho-1-benzoic acid --> 1 - (2<1> - phenylsulphoyl - 5<1> - sulphophenyl) - 5-pyrazolone - 3 - carboxylic acid ethyl ester, 5 - sulpho - 2 - amino - 1 - benzoic acid --> 1 - (4<1>-sulphophenyl) - 3 - phenyl - 5 - pyrazolone and anthranilic acid --> the 5-pyrazolone-3-carboxylic acid ethyl ester from 2-naphthylamine-4 : 8-disulphonic acid.  Other components specified are 3-bromo-, 3 : 5-dichloro-, 5-chloro-, 4-nitro-, 4-sulpho- and 3 : 5-disulpho-2-amino-benzoic acids, 4-aminodiphenyl-3-carboxylic acid, 2 : 3-aminonaphthoic acid; 1-phenyl-3-phenyl-5-pyrazolone, 1-phenyl-5-pyrazolone-3-carboxylic acid ethyl ester, 1-(2<1>-chlorophenyl)-3-phenyl-5-pyrazolone, 1-(2<1>-chloro-5<1>-sulphophenyl)-3-phenyl-5-pyrazolone, 1 - (4<1>-sulphophenyl)-5-pyrazolone-3-carboxylic acid ethyl ester, 1 - (2<1> - carboxy - 5<1> - sulphophenyl) - 3 - phenyl-5-pyrazolone, 1-(4<1>-sulphonaphthyl)-3-phenyl-5-pyrazolone, 1-(2<1>-phenylsulphoyl-5<1>-sulphophenyl) - 3 - phenyl - 5 - pyrazolone, 1 - (2<1>-hydroxy-3<1>-carboxy-5<1>-sulphophenyl) -3-phenyl-5-pyrazolone and 1-(2<1> : 4<1>-dichloro-6<1>-sulphophenyl)-3-phenyl-5-pyrazolone.
Patent GB-1434079-A (GB)
Title: Agricultural vehicle pallet loading machine
IPC: B60P1/38
Filed: 1973-09-24
Abstract: 1434079 Agricultural spreaders MASCHINENFABRIK FAHR AG GOTTMADINGEN 24 Sept 1973 [28 Sept 1972] 44655/73 Heading AID [Also in Division B8] An agricultural spreader vehicle 2 has a linkage 8 for raising and lowering a container 3 provided with a scraper chain 5, a spreading device 6, and a transverse conveyer belt 7, all of which are driven from a power means on a tractor 4 via an hydraulic, belt, or chain, drive which operates at varying container elevations.
Patent GB-1283219-A (GB)
Title: Turbine rotor
Inventor: SWEARINGEN JUDSON S
IPC: F01D5/04
Filed: 1969-09-10
Abstract: 1283219 Turbine rotors J S SWEARINGEN 10 Sept 1969 [9 July 1969] 44662/69 Heading FIT The flow passages of a turbine rotor are designed such that at given points the passage walls extend substantially parallel to the resultant of the deceleration and centrifugal forces acting on a particle entrained in the working fluid at the respective given point such that the particle is not directed against the passage walls. The working fluid may be a gas containing dust or liquid droplets, a vapour which partially condenses or a liquid which vapourizes in passing through the rotor. Flow through the latter may be initially radially inwards with axial or radial discharge, initially radially inwards changing to radially outwards, or axial. In a radially inward flow rotor it may not be practical for the blade surfaces to be arranged parallel to the resultant force in regions adjacent the blade outlet edge BD. Thus the edge may be cut back or a lip 20 or ridges 23 provided on the blade together with ridges 22 on the base of the flow passage, the lips and ridges influencing the working flow so as to reduce impingement of entrained particles on the passage walls. The path of an entrained particle through a flow passage is described in detail.
Patent GB-1065029-A (GB)
Title: A photographic camera
IPC: G03B19/12
Filed: 1965-10-22
Abstract: 1,65,029. Single lens reflex cameras. N. F. SEROV, I.S. BATJUTA and D. P. SIDOROVA. Oct.22, 1965, No. 44918/65. Heading G2A. In a single lens reflex camera having a movable mirror in a mount which mirror reflects light from the camera lens into a viewfinder 11 there is provided a movable light-proof blind 8 which is moved in front of the viewfinder by rotation of the mirror to its inoperative position prior to film exposure.
Patent GB-1069607-A (GB)
Title: Improvements in or relating to the production of quaternary fatty alkyl ammonium halides
Inventor: WILMSMANN HERMANN
Filed: 1965-10-26
Abstract: Novel quaternary pyridyl methyl fatty alkyl ammonium halides of the formula <FORM:1069607/C2/1> wherein R1 represents a saturated or unsaturated C8- 20 alkyl radical, R2 and R3 represent C1- 4 alkyl or hydroxyalkyl radicals and X represents hydrogen or a methyl group, are prepared by reacting a tertiary fatty amine of the formula NR1R2\R3 with a halo-methyl pyridine of the formula <FORM:1069607/C2/2> in a solvent.
Patent GB-1212760-A (GB)
Title: Preparation of salts of alkyl hydroxymethylene malonates
Inventor: TULL ROGER JAMES
IPC: C07C69/732
Filed: 1968-09-24
Abstract: 1,212,760. Alkyl hydroxymethylene malonates and salts thereof. MERCK & CO. Inc. 24 Sept., 1968 [2 Oct., 1967], No. 45361/68. Heading C2C. Alkali metal salts of C(1-5) alkyl hydroxymethylenemalonates are prepared by reacting a C(1-5) alkyl malonate with a C(1-5) alkyl formate in the presence of a strong alkali metal base. The reaction is carried out either with a molar excess of formate; in a closed system; at between 20 and 35‹ C; or using methyl formate as the alkyl formate. A positive pressure of carbon monoxide may be maintained and the resulting salts reacted with strong acid to produce the corresponding alkyl hydroxymethylene malonate which may be alkylated e.g. with dimethyl sulphate to the alkylalkoxymethylene malonate.
Patent GB-1401352-A (GB)
Title: Anchor devices
IPC: F16B19/00
Filed: 1972-10-02
Abstract: 1401352 Clamps ILLINOIS TOOL WORKS Inc 2 Oct 1972 [2 Oct 1971] 45363/72 Heading E2B A one piece plastics clamping device comprises a base portion comprising parts 1 and 1', a cam element 3 pivotally connected to the part 1' a clamping part 2 pivotally connected to the part 1, the part 3 having a projection 8 which, when the cam element 3 is moved to abut the clamping part, pivots the clamping part to clamping position where it is retained by a latch. An edge of an article inserted between the parts 1 and 2 is clamped between ridges 4, 5 on the parts when the projection 8 engages the part 2 and a notch 9 in the projection engages a shoulder 7 on the part 2. Reinforcing ribs 10 and 11 (not shown) on the part 2 are provided. An anchor member 13 extends from the part 1 and comprises a stem and spring fingers. The device, Fig. 4 comprises hollow parts with central internal reinforcements and with an external reinforcing rib 24 extending between an extension of the base parts 14 and 18.
Patent GB-1062935-A (GB)
Title: Electrophotographic copying material
IPC: C07D241/42
Filed: 1963-11-18
Abstract: 1,062,935. Electrophotographic material. KALLE A.G. Nov. 18, 1963 [Nov. 24, 1962], No. 45452/63. Heading H1K [Also in Division G2] An electrophotographic material has a support bearing a photoconductive insulating layer containing one or more 2 : 3-disubstitutedquinoxalines which may be further substituted in the carbocyclic ring by monovalent substituents or by ortho-condensed carbocyclic rings. The quinoxaline has to contain at least one substituted or unsubstituted amino group. Many suitable quinoxalines are listed. Commonly known supports are suggested. A resinous binder is optional. Suitable examples are given. The photoconductive layer may include a dyestuff sensitizer. Specific materials disclosed are: (A) 2-phenyl.3-(4<SP>1</SP>-diethylamino. phenyl)-quinoxaline with a polyindene resin and crystal violet, supported by pre-treated paper; (B) 2 - phenyl - 3 - (4<SP>1</SP>- dimethylaminophenyl)-quinoxaline with a ketone resin and Brilliant Green on an aluminium-paper laminate; (C) An equimolecular mixture of the 6- and 7- methoxy derivatives of the quinoxaline of Example B mixed with a styrene copolymer having carbonyl groups and with Rhodamine B, and applied to a severely roughened aluminium foil; (D) 2 : 3-bis-(4<SP>1</SP>-methoxy-phenyl)- 6 - amino - quinoxaline with a resin - modified maleic acid resin and Eosin S, on pre-treated paper; (E) A mixture of 2-(4<SP>1</SP>-chlorophenyl)- 3 - (4<SP>1</SP> - dimethylamino -  phenyl) - quinoxaline, 2- phenyl - 3 - (4<SP>1</SP> - dimethylamino - phenyl) - 6 : 7- benzo-quinoxaline, and 2 : 3-bis-(4<SP>1</SP>-methoxyphenyl) - 6 - amino - quinoxaline, on a brushed aluminium foil; (F) An equimolecular mixture of the 6- and 7-chloro derivatives of the quinoxaline of Example B together with an equimolecular mixture of the 6- and 7-methoxy derivatives of the same quinoxaline and a phenol-formaldehyde resin and Patent Blue AE applied to pre-treated paper; (G) 2-phenyl- 3 - (4<SP>1</SP> - dimethylamino - phenyl) - 6 : 7 - benzoquinoxaline mixed with 2 : 5-bis-(4<SP>1</SP>-dimethylamino - phenyl) -1 : 3 : 4 - oxadiazole, a ketone resin, and methyl violet applied to an aluminium-paper laminate; (H) 2 : 3 - bis - (4<SP>1</SP>- amino-phenyl)-quinoxaline, chlorinated rubber, and Bengal Rose on pre-treated paper; (J) An equimolecular mixture of the 6- and 7-amino derivatives of the quinoxaline of Example B mixed with a processed natural resin and applied to pre-treated paper; (K) 2 : 3-bisphenyl - 6 - dimethylaminophenyl - quinoxaline with a maleinate resin and Rhodamine B Extra on a roughened aluminium foil.
Patent GB-1108976-A (GB)
Title: A process for the manufacture of benz[e]idenes
IPC: C07D317/16
Filed: 1966-10-11
Abstract: Compounds of the formula <FORM:1108976/C2/1> (wherein R1 is lower, i.e. C1- 6, alkyl; and Z is CO or CHOR2, R2 being H, lower alkyl, lower alkanoyl, benzoyl, nitro-benzoyl, carboxy-lower alkanoyl, carboxyl-benzoyl, trifluoro-acetyl or camphorsulphonyl) are prepared by hydrogenating in the presence of a noble metal catalyst compounds of the formula <FORM:1108976/C2/2> (wherein Z1 is CO or CHOR20, R20 being H, lower alkyl, lower-alkoxy-lower alkyl, phenyl-lower alkyl, tetrahydropyranyl, lower alkanoyl, benzoyl, nitro-benzoyl, carboxy-lower alkanoyl, carboxy-benzoyl, trifluoroacetyl or camphorsulphonyl; and T is -CX=CH-, -C(OR3)=CH- or -Q-CH2-, R3 being lower alkyl, X being Cl, Br or I, and Q being CO, lower alkylenedioxymethylene, di-lower alkoxy-methylene, hydroxymethylene, tetrahydropyranyloxy-methylene or phenyl-lower alkoxy-methylene) to yield a mixture of a compound of the formula <FORM:1108976/C2/3> (wherein T1 has all the above values of T except the last two) and a corresponding 3ab ,4b -stereoisomeric derivative thereof, epimerizing, and cyclizing the epimerization product of the formula <FORM:1108976/C2/4> said cyclization being carried out simultaneously with or following said epimerization. These last-named processes may be effected with acid or base.  Deketalization may occur simultaneously or may be effected separately. An enol-ether or enol-halide side chain may also be hydrolysed in the acid treatment. A side chain hydroxy group should be oxidized to a keto group before cyclization.  Products of the present process may be resolved by standard procedures, or resolved starting materials may be used. 3-Hydroxy products may be oxidized to 3-ketones.