baber/WOPTO huggingface dataset:
Patent GB-1440460-A (GB)
Title: Acyl hydrazones
IPC: C08L27/00
Filed: 1973-09-17
Abstract: 1440460 Phenolic antioxidants SANDOZ Ltd 17 Sept 1973 [21 Sept 1972 4 Oct 1972] 43512/73 Heading C3P [Also in Division C2] Plastics material, e.g. polypropylene powder is stabilized against oxidative degradation by a compound of the formula wherein R 1  is tertiary alkyl (C 4 -C 12 ), R 2  is alkyl (C 1 -C 20 ), cycloalkyl (C 5 -C 12 ), cycloalkyl (C 5 -C 11 ) alkyl (C 1 -C 7 ), aralkyl (C 7 -C 12 ) phenyl, or aralkyl (C 7 -C 12 ) or phenyl mono- or di-substituted on the aromatic nucleus thereof by alkyl (C 1 -C 6 ), R 3  is hydrogen or alkyl (C 1 -C 20 ), X is a direct linkage, or 1,3- or 1,4-phenylene, Y is oxygen or -NH- and Z is hydrogen; alkyl (C 1 -C 22 ); cycloalkyl (C 5 - C 12 ); cycloalkyl (C 5 -C 11 ) alkyl (C 1 -C 7 ); aralkyl (C 7 -C 12 ); aryloxyalkyl (C 7 -C 12 ); arylthioalkyl (C 7 -C 12 ); aralkyl (C 7 -C 12 ), aryloxyalkyl (C 7 - C 12 ) or arylthioalkyl (C 7 -C 12 ), monosubstituted on the aromatic nucleus thereof by alkyl (C 1 -C 4 ) or alkoxy (C 1 -C 4 ); phenyl, or phenyl mono-, di- or trisubstituted by 1, 2 or 3 of the groups alkyl (C 1 -C 9 ), alkoxy (C 1 -C 9 ), alkylthio (C 1 -C 9 ) (with C 1 -C 14  in the aggregate of the substituents alkyl, alkoxy and/or alkylthio), halogen, hydroxyl, cyano, COOR 4 , phenoxy, phenyl, phenyl substituted by 1 or 2 alkyls (C 1 -C 9 ) and/or by hydroxyl, wherein. R 4  is hydrogen, alkyl (C 1 -C 18 ), cycloalkyl (C 5 -C 12 ), cycloalkyl (C 5 -C 11 ) alkyl (C 1 -C 7 ), aralkyl (C 7 -C 12 ), phenyl or phenyl monosubstituted by hydroxyl and/or mono- or di-substituted by alkyl (C 1 -C 9 ); and when Z is alkyl, cycloalkylalkyl or substituted or unsubstituted aralkyl, aryloxyalkyl, arylthioalkyl or alkyl, alkoxy or alkylthio substituted phenyl, then any aliphatic alkyl chain thereof is either uninterrupted or is interrupted by 1 or 2 ether and/or thioether linkages and when Y is oxygen, then Z may also be nickel, zinc, manganese or copper.
Patent GB-1410176-A (GB)
Title: Conversion cotaings on metal
IPC: C23C22/12
Filed: 1972-09-21
Abstract: 1410176 Zinc phosphate conversion coatings DULUX AUSTRALIA Ltd 21 Sept 1972 [5 Oct 1971] 43801/72 Heading C7U A ferrous or zinc surface is formed with a zinc phosphate coating using an aqueous solution comprising a zinc orthophosphate, hydrogen ions, and at least 0.1 g/l of an addition copolymer of monomer (a) and monomer (b) where (a) is selected from the group maleic acid or anhydride fumaric acid, and citraeonic acid and (b) is selected from the group consisting of ethylene, and methyl vinyl, ethyl vinyl or cyclohexy vinyl ether. The pH may be 2 to 3.5 and the solution is non-gassing and may contain sodium nitrite and hydrogen peroxide.
Patent GB-1399901-A (GB)
Title: Flex reel
IPC: B65H75/34
Filed: 1972-09-22
Abstract: 1399901 Spring drum apparatus PHILIPS GLOEILAMPENFABRIEKEN NV 22 Sept 1972 [25 Sept 1971] 43952/72 Heading B8B A self reeling supply flex reel for an electrical appliance 1 comprises a rotatable drum 11 for flex 23, a part 2 rigidly secured to the appliance 1 and housing a spiral spring 8, and sliding electrical contact members 12, 13, 25 between the fixed part 2 and the drum 11. The spring compartment 2 houses a cylindrical box 5 containing the spring 8, the outer end of which spring is secured to the compartment 2 and the inner end of which is located in one of a plurality of recesses in the periphery of a hub 18 of the drum 11. The compartment 2 is closed by a plate 9 which mounts a pin 10 on which the drum hub 18 rotates. The flex 23 passes through the hub wall 22 of the drum 11 for clamping at 26 and for electrical connection to two contacts 24 which each terminate in a contact 25 for sliding engagement with the contacts 12, 13 on the fixed part 2. Contact strips 14, 17 connect the contacts 12, 13 to the appliance supply.
Patent GB-918395-A (GB)
Title: Dithiophosphonic acid esters
IPC: A01N57/18
Filed: 1960-12-21
Abstract: The invention comprises dithiophosphonic esters of formula <FORM:0918395/IV (b)/1> where R is C1-6 alkyl, phenyl, chloro-substituted phenyl, C1-4 alkoxy-substituted phenyl or cyclohexyl, R1 and R2 are C1-4 alkyl, hydrogen or phenyl, one of them being hydrogen or alkyl, but not more than one being hydrogen, or <FORM:0918395/IV (b)/2> forms a 6-membered heterocyclic ring, R3 is C1-4 alkyl and Alk is a straight or branched chain alkylene radical of up to 4 carbon atoms.  They may be prepared by reacting a dithiophosphonic acid anhydride RPS2 with an aminoalcohol HO-Alk-NR1R2 and reacting the O - aminoalkyl dithiophosphonic acid betaine salt thus obtained with an alkyl halide R3Hal in the presence of an acid binding agent.  The products are insecticides. Intermediates prepared in examples are the O-dimethylaminoethyl and O-diethylaminoethyl esters of methyl-, ethyl-, cyclohexyl and p-hydroxyphenyl-phosphonodithioic acids, the O-diethylaminoisopropyl esters of ethyl-, cyclohexyl- and p-hydroxyphenyl-phospnonodithioic acids, and O-methylaminoethyl hydrogen ethylphosphonodithioate, presumably in the betaine form.ALSO:Insecticidal compositions comprise a dithiophosphonic ester of formula <FORM:0918395/VI/1> where R is C1-6 alkyl, phenyl, chloro-substituted phenyl, C1-4-alkoxy-substituted phenyl or cyclohexyl, R1 and R2 are C1-4 alkyl, hydrogen or phenyl, one of them being hydrogen or alkyl, but not more than one being hydrogen, or <FORM:0918395/VI/2> forms a 6-membered heterocyclic ring, R3 is C1-4 alkyl and Alk is a straight or branched chain alkylene radical of up to 4 carbon atoms, together with a carrier.  Known insecticides and/or fertilisers may also be present.  Specified solid carriers are talc, chalk, bentonite and clay.  Liquid carriers, which may contain emulsifiers, e.g. benzyl hydroxy diphenyl polyglycol ether, are alcohols, e.g. methanol or ethanol, ketones e.g. acetone or methyl ethyl ketone or liquid hydrocarbons.
Patent GB-1127085-A (GB)
Title: 2,6-dicyano-4-nitroaniline and process for producing it
Inventor: GOTTSCHLICH ALOIS
IPC: C07C255/58
Filed: 1967-09-27
Abstract: 1,127,085. 2,6-Dicyano-4-nitro-aniline. FARBENFABRIKEN BAYER A.G. 27 Sept., 1967 [15 Oct., 1966], No. 44004/67. Heading C2C. [Also in Division C4] The invention comprises 2,6-dicyano-4-nitroaniline. It may be obtained by reacting 1,3- dicyano-5-nitrobenzene with hydroxylamine or a salt thereof in the presence of a compound having the properties of an alkali. Examples are given for the product of the compound. It may be used in the production of 1,4-diamino- 2,6-dicyanobenzene and as a diazo component in the production of azo dyes.
Patent GB-1501569-A (GB)
Title: Tricyclo(6.2.1.02,6)undeca-2(6)-ene and process for hydride transfer reduction rearrangement of same
IPC: C07C5/03
Filed: 1976-10-25
Abstract: 1501569 Tricyclo[6,2,1,0<SP>2,6</SP>]undeca-2(6)-ene KAO SOAP CO Ltd 25 Oct 1976 [28 Oct 1975 7 Nov 1975] 44237/76 Heading C5E Tricyclo[6,2,1,0<SP>2,6</SP>]undeca-2(6)-ene (claimed per se) may be converted to tricyclo[5,3,1,0<SP>3,8</SP>]undecane by simultaneous isomerization and reduction with H 2 SO 4  of concentration 75-100% at -20‹ to +100‹ C. in the presence of a liquid aliphatic or alicyclic hydrocarbon. The starting material may be obtained by dehydrating and isomerizing in the presence of phosphoric acid, 5,6 - exo - trimethylene - 2 - norbornylcarbinol, 2 - hydroxy - 6,7 - exo - trimethylene bicyclo[3,2,1]octane, 3 - endo - hydroxy - 6,7 - exotrimethylene bicyclo[3,2,1]octane, or 2 - hydroxy - 5,6 - endo - trimethylene bicyclo[2,2,2]octane, or by isomerizing, in the presence of phosphoric acid, 6,7-exo-trimethylene bicyclo[3,2,1]oct-2-ene.
Patent GB-1061328-A (GB)
Title: A method of sintering and/or heat treating workpieces consisting of metals with a high affinity for oxygen
IPC: C22F1/00
Filed: 1965-10-19
Abstract: Beryllium and the refractory transition metals of Groups IV, V and VI of the Periodic Table or their alloys are heat treated and/or sintered in a technical grade noble gas, preferably technical grade argon, the workpieces being packed and completely covered in granular refractory oxide material such as Al2 O3, ZrO2, MgO, CaO, SiO2, TiO2 and Cr2O3.  The examples given relate to the sintering of Ti-Zr powder, Ti powder and the heat treatment at 900 DEG C. of a Ti alloy containing 5% Al, 5% Sn, 5% Zr.
Patent GB-1077827-A (GB)
Title: Improvements in or relating to case fastenings
Inventor: LITTLE JOHN
IPC: H01H9/02
Filed: 1964-10-30
Abstract: 1,077,827. Riveted joints. PAINTON & CO. Ltd. Oct. 11, 1965 [Oct. 30, 1964], No. 44381/64. Heading B3U. [Also in Divisions E2, H1 and H2] Parts 21, 22 (Fig. 8) of a casing for a potentiometer or other electrical components are held together by fastening devices, e.g. plates 22 which fit round and are secured to members projecting from the casing parts. Heat can be applied by a hot member 31 passing therefrom to frusto-conical projections on the casing parts which fit into tapered holes 27 on the plate 22. On the application of heat and pressure the thermoplastic material of the root portions flows outwardly through the holes 27. If the projecting parts are -arranged in contacting pairs the fastening devices may be plain washers (Fig. 6, not shown), heat and pressure being used to deform the projecting members which are of thermoplastics material, to form a a head portion which holds-the washer in place.
Patent GB-1486769-A (GB)
Title: Moulding processes and apparatus
IPC: B29C35/02
Filed: 1974-09-16
Abstract: 1486769 Mixing apparatus ROWLEY (R & D) Ltd 16 Sept 1974 44572/73 Heading B1C [Also in Division B5] In a method of moulding a composite article in which the mould cavity is defined by a pair of removable liners, one or both liners is coated with material for forming an outer surface on the article before the liners are located between the mould halves. The moulding material may be a resinous or a ceramic material or concrete and the liners may be held in place by vacuum. Injection moulding. Fig. 1 shows apparatus comprising a mould 10 on a vibration pad 12, mixing tanks 14 having feed screws 15 and worm conveyor 16 for feeding moulding material through pipes 18 and a flexible boom 20 to an injection gun 25 which comprises a mixing chamber 40, Fig. 2, having inlets 41, (42) for resin and additives and a mixing device 50. The spindle 48 of the mixing device may carry a worm 56 and a deflector 58 which prevents displacement of reinforcement in the mould by the incoming moulding material. In a modification the injection gun is fed from a wheeled assembly comprising a worm conveyor supplied from a tank.
Patent GB-1120811-A (GB)
Title: Improvements in or relating to the treatment of leather
Inventor: COULSON RONALD GEOFFREY
IPC: A43D21/02
Filed: 1964-11-02
Abstract: 1,120,811. Boots &c. SHOE & ALLIED TRADES RESEARCH ASSOCIATION. 1 Nov., 1965 [2 Nov., 1964], No. 44659/64. Heading A3B. Apparatus for stretching a shoe upper forepart 1 consists of three clamps 2, 3, 4 which are moved away from each other to stretch the forepart. The clamps 2, 3, 4 are carried on the upper ends of levers which are pivoted to the machine frame at their lower ends and which are moved apart by a cam disc 7 which engages cam followers 6 on the levers. The cam disc 7 is rotated by a worm gear 9 on a shaft 9a, translational and/or rotational movement of the shaft 9a causing rotation of the cam disc 7. The pivot point of the lever carrying the clamp 2 is adjustable in position to accommodate different shapes and sizes of foreparts 1. The forepart may also be shaped by a lobed mould of the type described in Specification No. 1,096,002.
Patent GB-1184236-A (GB)
Title: Process for the recovery of an N-Tritylamine from its Solution in an Organic Solvent
Inventor: PLAS FRANCISCUS JOHANNES FREDE
IPC: C07D295/03
Filed: 1967-10-03
Abstract: 1,184,236. N-Tritylamines. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 3 Oct., 1967, No. 44888/67. Heading C2C. N-Tritylamines which are insoluble or substantially insoluble in water are recovered from solutions in one or more organic solvents by feeding the solution to an aqueous medium at an elevated temperature, the solvent being simultaneously removed by distillation and the N-tritylamine separated in the solid state from the resulting aqueous dispersion. Preferred N- tritylamines are the N-triphenylmethyl derivatives of pyrrolidine, tetrahydropyridine, 1,2- oxazolidine, piperidine and morpholine.
Patent GB-1329307-A (GB)
Title: Method of operating piezoelectric transformers
IPC: H01L41/107
Filed: 1970-09-24
Abstract: 1329307 Piezo-electric transformers DENKI ONKYO CO Ltd 24 Sept 1970 [29 Sept 1969] 45425/70 Heading H3U To improve the voltage regulation of a peizo-electric transformer 10 driven by a voltage from the horizontal deflection circuit 50 of a television receiver and suppling a high voltage to a CRT 40, the input electrode if the transformer is connected to the driving voltage source through a variable reactance circuit 60 including a reactor 62 and capacitor 61. The frequency of oscillation of the oscillatory circuit comprising the transformer 10 and the cirouit 60 is adjusted by varying 61 or 62 so that it differs by a small amount #f 0  from n/2 times the natural resonance frequency f 0  of the transformer.
Patent GB-1429544-A (GB)
Title: Method and apparatus for determining whether a given zone is occupied by an edge of a transparent sheet or ribbon
IPC: C03B35/00
Filed: 1973-09-28
Abstract: 1429544 Detecting edge of transparent sheet photo-electrically GLAVERBEL-MECANIVER 28 Sept 1973 [3 Oct 1972] 45494/73 Heading G1A To detect the presence or position of a glass ribbon 10 in an annealing lehr 11 a light beam 5 is caused to scan to and fro across the ribbon and enters an edge 8 or 9 of the ribbon wherein it is internally reflected so that it produces a deflected beam 6 or 26 respectively producing respective pulses at detector 21 at time intervals indicative of the width of the ribbon, which intervals are determined by timing device 23. The beam is produced by a laser 20 and rotating mirror 18 and passage of a direct beam to the detector is prevented by screen 25, or the roof 14 and/or bottom 12 of the lehr may be opaque. In an alternative embodiment Fig. 4 (not shown) a reference detector (27) is disposed to receive a beam from the mirror without it passing through the glass ribbon, reception of which beam causes detector (27) to transmit a pulse to start the timing device 23. Angle alpha is swept by the beam in scanning from the reference detector to the edge of the ribbon 10 whereby it is deflected to reach detector 21 which pulses the timer to stop, whereby the angle alpha, and thus the position of the edge of the ribbon, may be determined. If the position of the other edge is determined then the position of the ribbon inside the lehr may be determined. Alternatively, Fig. 5 (not shown) the laser itself is pivoted to scan the glass ribbon.
Patent GB-952164-A (GB)
Title: Improvements in or relating to hangers for elongated members such as electric cables or pipes
Inventor: WEBB RONALD ALEXANDER
IPC: F16L3/22
Filed: 1959-03-10
Abstract: 952,164. Brackets. CABLE SUPPORTS Ltd. Feb. 26, 1960 [March 10, 1959], No. 45707/63. Divided out of 952,163. Heading A4B. [Also in Divisions E2, F2 and H2] A hanger has a hook 18 capable of supporting an elongated member such as a pipe or cable, and a head 17, which has a thickness greater than the thickness of the solid part of the hanger at the hook so that the head extends partially over the hook and which head is adapted to be secured by and to slide along and be supported by a horizontal C-shaped channel 26 so that when so supported an elongated member such as a pipe or cable can be placed in the hook and retained thereby. A closure element 12 for closing the mouth of the hook can also be provided; the head portion of this is also thicker than the remainder so that it overlies the elongated member. The hanger and closure element are both provided with edge grooves 31 for engaging flanges 29 of the channel and are held together by a bolt 14 and nut 13. Relative rotation is prevented by dowels 24 on the closure element which engages rectangular sockets 23 in the hanger. For engagement with the channel 26 when vertical the hanger has surfaces 42 separated by projecting means 32 as disclosed in Specification 952,163. The closure element has a groove 35 to secure the projecting means of an adjacent hanger when a number of hangers and closure elements are used.
Patent GB-1097652-A (GB)
Title: Digital automatic impedance bridge circuit
IPC: G01R17/00
Filed: 1965-11-02
Abstract: 1,097,652. Automatic bridge circuit. GENERAL RADIO CO. Nov. 2, 1965 [May 11, 1965], No. 46376/65. Heading G4H. In an automatic impedance bridge, in which an unknown impedance is measured against a known impedance, unbalance of the bridge is detected and used through a logic-circuit, to control means for successively changing the ratio of the bridge arms, successively to reduce the degree of bridge unbalance. In the form of Fig. 1, the centre-earthed secondary of a transformer T forms two arms of the bridge, one of which can be varied by switching circuits 4. The capacitance Cx to be measured and the standard capacitor Cs form the other two arms of the bridge. Unbalance of the bridge is detected by a phase detector 3 controlling a counter 19 through logic circuits 20 so as to switch the circuits 4 until a balance is reached. The value of the counter is then displayed 21. In Fig. 2 (not shown), the counter (19) connects tappings (T1-T3) of the transformer successively until a balance is reached. The counter counts up or down according to the signal on control lead 2 and clock pulses (from 17) first pass to the most significant decade of the counter through a gate (G1). When the bridge over-balances the sign of the output of the detector 3 changes, so that the other signal is applied to the counter control to make it count backwards. Simultaneously an auxiliary counter (13) advances to the second position, opening gate G2, so that the pulses pass to the next denomination. The sign is reversed at the next change in the comparator output and the third decade receives the pulses. By this means the counter converges quickly on to the balance value. The switches used to effect the balance may be transistors. The impedance may comprise a combination, say of resistance and capacitance, and there may be two balancing circuits, as described, one for resistance and the other for capacitance.
Patent GB-951688-A (GB)
Title: Improvements in grinding mills
IPC: B02C15/00
Filed: 1961-12-28
Abstract: 951,688. Roller-and-ring mills. M. S. MISCHANSKI. Dec. 28, 1961 [Jan. 9, 1961], No. 46437/61. Heading B2A. A mill comprises grinding rollers 22 coacting with a grinding ring 17, the rollers being rotatable on shafts 23 secured to yokes 26 which are slidably connected by means of cylindrical rods 31, 32 to spiders 29, 30 secured to a driven shaft 18, the yokes being radially movable, to move the rollers into engagement with the grinding ring, by centrifugal force and by fluid pressure acting on pistons 38 against the action of springs 77. Air is drawn through openings 70 by means of a cyclone collector. Ploughs 75 secured to the yokes throw coarse material falling on a platform 72 upwardly into the grinding zone. In a modification, each yoke carries a pair of grinding rollers.
Patent GB-1248056-A (GB)
Title: Confining system for fluid cushions in ground effect vehicles
Inventor: GIRAUD FRANCOIS LOUIS
IPC: B60V1/00
Filed: 1968-10-01
Abstract: 1,248,056. Air cushion vehicles. SOC. DE L'AEROTBAIN. 1 Oct., 1968 [4 Oct., 1967; 19 June, 1968], No. 46471/68. Headings B7K and B7L. A skirting system for a tracked air cushion vehicle comprises a wall 7 bolted to an angle bar 9 which is pivotally connected by rod 10 to a part 13 of the vehicle body. Rod 10 is bent to pass through hinge lugs 11, 12 and 14, and is also attached to the vehicle body at 15 to act as a torsion spring. Several walls 7 may be used to provide a spring-loaded skirting system for confining an air cushion to support the vehicle above the track 1. A yieldable member 17 secured to the angle bar 9 and to the vehicle frame prevents loss of cushion air past pivot 11. The cushion so confined may be subdivided by a system such as shown in Fig. 4, wherein two partitions 18, 19 are rigidly riveted to a deformable diaphragm 23 attached to a depending part 24 of the vehicle body. If the cushion pressure in a subdivision such as 27 drops, because of undue leakage past the primary skirting system, the two partitions will rotate clockwise in Fig. 4, thereby decreasing the gap 26 between partitions 19 and the track 1 and minimizing loss of cushion air or hoverheight. An alternative spring damping suspension is also described for the partitions, Figs. 5, 6 (not shown). The subdividing partitions are described and claimed in Specification 1,248,055.
Patent GB-1365336-A (GB)
Title: Automatic central buffer couplings for railway vehicles
IPC: B61G3/18
Filed: 1971-10-07
Abstract: 1365336 Automatic central buffer couplings GERMANY MINISTRY OF TRANSPORT 7 Oct 1971 46695/71 Heading B7T In an automatic central buffer coupling for a rail vehicle having a casing at its head containing a locking mechanism of the type wherein, on a coupling operation with an identical countercoupling, a locking bolt 14 swings in a vertical plane from its position in the ready-forcoupling, i.e. Fig. 1, state of the mechanism to an intermediate position in which the front part of the bolt is partially retracted into the casing and thence to its position in the locked, i.e. Fig. 3, state, of the mechanism, and, during the swinging of the bolt, a feeler 9 located at the front of a lock support 8 pivoted on a pin 4 is progressively swung, against the action of a counter-weight 10 at the rear of the support, from the Fig. 1 position, in which the feeler projects from the casing, to the Fig. 3 position, in which the feeler is fully retracted into the casing and a catch 11 on the support 8 is engaged with a cam surface 18 on a locking pawl 17 journalled on a pin 16 on the bolt 14 so as to lock the mechanism, and wherein there are a release device 19, 20 to unlock the mechanism and an indicator to show the various positions of the bolt 14, a safety pawl 5 is provided which extends rearwardly and downwardly from the pin 4 and has a lower bearing face 7 inclining rearwardly and upwardly, and the support 8 is mounted on the pin 4 by means of an elongate slot and has a recess 12 which receives the pawl 5 and is formed with a stop 13, whereby, if a shock impact occurs on coupling, the support 8 is caused to slide relative to the pin and the stop 13 comes into engagement with the face 7 of the pawl 5 thereby preventing pivotal movement of the support 8 and bolt 14 and avoiding damage to the locking mechanism. The pin 4 may be mounted on a vertical partition extending from top to bottom and from front to rear of the casing.
Patent GB-1348151-A (GB)
Title: Tray
IPC: B65D1/34
Filed: 1971-10-07
Abstract: 1348151 Trays PHILLIPS PETROLEUM CO 7 Oct 1971 [8 Oct 1970] 46791/71 Heading A4A [Also in Division B8] In a self-draining tray comprising walls 12, 12<SP>1</SP>, 14 and 14<SP>1</SP> and a grid bottom, radiused fillets 38 are provided at every junction between the walls and the grid bottom and at every intersection in the grid bottom. The upper ends of the walls may be curved outwardly to form a peripheral flange Fig. 5 (not shown). In another embodiment Fig. 3 (not shown) each wall may include a curved shoulder (30, 32) connecting a lower portion of the wall with an outwardly offset upper portion (28) of the wall. The grid bottom may comprise intersecting first and second grid members 34, 36 with, Fig. 1, or without, Fig. 6, further grid members 40, 42 extending diagonally of rectangles defined by the first and second grid members 34, 36. The grid members intersect at reinforcing islands (46), Fig. 4 (not shown) which may be solid or apertured as at 48.