4711 4715.output

* GB785118 (A)

Description: GB785118 (A) ? 1957-10-23

Improvements in or relating to electric spotlights

Description of GB785118 (A)

PATENT SPECIFICATION 785,118 Inventors:-SYDNEY HUBBOLD and MARTIN WESTLEY PEIRCE. Date of filing Complete Specification: Sept 1, 1956. Application Date: Sept 14,1954 No 26638154. Complete Specification Publisaied: Oct 23, 1957. Index at Acceptance:-Classes 38 ( 5), B 1 (D 2 X: V), B 2 C 5 A; 75 ( 3), D 4 (A: B: D); ( 4), O l; and 97 ( 1), H. International Classification:-1 F 2 b G 03 b H 102 c COMPLETE SPECIFICATION. Improvements in or relating to Electric Spotlights. We, Ti E GENERAL ELECTRIC C Oi MPLY L Mu ITED, of Magnet I Iouse, Kingsway, London, W C 2, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to electric spotlights, and the object of the invention is to provide a form of spotlight which can be readily used by a lecturer in a lecture theatre to indicate to an audience particular points of lantern slides, large drawings, or the like, being shown on a screen or wall. According to the invention an electric spotlight has a casing comprising a bulbous end portion containing a holder for an electric lamp, and a barrel portion projecting from the end portion and containing an optical system arranged on illumination by the lamp to project an image suitable for indicating a point or region of a screen, wall or the like (hereinafter referred to simply as a screen) on to which the image may be projected in use of the spotlight, the bulbous end portion being shaped and weighted so that the casing has a determinate rest position when resting with the bulbous end portion on a horizontal surface and so that when the casing is tilted from said

rest position for directing said image on to a screen, and is subsequently released, the casing returns automatically to the said determinate rest position. In use of the spotlight, it is arranged that in the said rest position of the casing the image is deflected off or to the side of the screen, so that the image can be brought on to the screen by a suitable tilting of the casing from the rest position and the image is automatically directed off or to the side lPrice 3 s 6 d l of the screen when the casing is released. The relative orientations of the bulbous end portion and barrel portion suitable for 45 effecting this can, of course, be different in different cases but preferably it is arranged that in the rest position the barrel portion of the spotlight projects substantially vertically upwards so that the spotlight may be used 50 with different sizes of screens arranged in a vertical plane. The image itself may, for example, consist merely of a circular spot of light, or it may be in the form of an arrow or cross or other 55 shape depending on the particular purpose for which the spotlight is to be used The spotlight preferably includes an electric switch connected in series with the terminals of the lamp-holder for enabling the lamp to be 60 extinguished when the spotlight is not in use. Preferably the switch is arranged to operate automatically so as to break the circuit to the lamp-holder when the spotlight casing is in the rest position, and to re-make 65 the circuit when the casing is tilted from the rest position. Thus the switch may be in the form of a push-button switch in which the switch contacts are closed in the normal unoperated 70 position of the button and are opened when the button is depressed, the switch being so constructed and so attached to the bulbous end portion that when the spotlight takes up said rest position on a horizontal surface 75 said surface depresses the button and opens the switch contacts In some cases however other forms of switch, for example a mercury switch, may be employed for automatically breaking the circuit to the terminals of the 80 lamp-holder when 'the spotlight casing is in the rest position. Alternatively, instead of an automatically operated switch, a switch which is arranged 785,118 to be operated manually may be provided for switching the lamp on and off as required in use of the spotlight. In the preferred form of spotlight embodying the invention the bulbous end portion has an outer surface of substantially spherical form, flattened on one side and having the barrel portion projecting substantially perpendicular to said flattened region on the other side, the bulbous portion being so weighted that in said rest position the flattened region constitutes the base of the arrangement with the

barrel portion projecting substantially vertically upwards. : l a The bulbous end portion may, for example, be cast in a suitable metal and the weighting may then conveniently be effected by forming the flattened side of the end portion with a thickened wall. One particular spotlight construction in accordance with the preferred form of the invention will now be described by way of example with reference to the schematic drawing accompanying the Provisional Specification which is a part-sectional view in a plane through the axis of the spotlight. The spotlight shown comprises a hollow metal body 1 which provides the said bulbous end portion, and which has a part spherical outer surface flattened on one side and provided with a circular opening 2, of larger diameter than the flattened region 3, immediately opposite thereto. A circular plate 4 is attached to the body 1 over the opening 2, and studs 5, which pass. through holes near the circumference of the plate into tapped holes formed in a flange 6 extending inwards from the edge of the opening, hold the plate rigidly in place At the centre of the plate 4 there is provided a circular aperture surrounded coaxially on the side of the plate remote from the body 1 by a hollow cylindrical projection 7, formed integrally with the plate, the inner surface of the projection being threaded at each end. A metal diaphragm extends across the bore of the projection 7 between the two threaded portions, and is provided at the centre with an arrow-shaped aperture 13 arranged to be illuminated in operation of the spotlight by an electric light bulb 15 mounted within the hollow spherical body 1. Into the inner end of the cylindrical projection 7 there is screwed a condensing lens system 9, a barrel portion 10 carrying the projection lens 14 being screwed into the opposite end This barrel portion 10 comprises an outer cylinder 11 threaded at one end, which end is screwed into the outer end of the projection 7, and an inner cylinder 12 free to slide axially within the outer cylinder for focusing the image 23 of the arrow 13 on to a wall or screen and carrying the projection lens 14 at its outer end. The light bulb 15 is mounted in a suitable holder 16 with the filament of the lamp behind the condensing lens system 9, the holder 16 being mounted in turn on a metal bracket 17 secured to the inner surface of the plate 4 Leads 18, 19 to the terminals of the lamnp 70 holder pass through an aperture in the plate 4, the lead 18 being connected directly to one of the terminals of the holder, and the lead 19 being connected to the other terminal through a micro-gap switch 20 secured to the 75 centre of the inner face of the closed end of the body 1 of

the spotlight The switch is operated by a push-button 21 which extends through a hole 22 in the closed end of the body 1, the switch contacts being closed in;i O the normal unoperated position of the push-button, and opened when the button is pushed inwards against the bias of a spring, the spring being arranged to return the button to the normal "on" position 85 when pressure on the button is released. The wall of the body 1 is thicker at the closed end, the weight of the thickened end wall being such that when the body is resting on a substantially horizontal surface 90 the spotlight normally finds a position of rest with the barrel portion 10 extending vertically upwards and the flattened end of the body 1 acting as a base In this position the push-button 21 is pressed in by said 95 horizontal surface thus holding the switch contacts open, the switch thereby interrupting the supply of current to the lamp in operation of the spotlight However when the spotlight is moved from its position of loo rest, for example to project an image on a screen, the rotation of body 1, as the barrel portion is tilted towards the screen, raises the closed end of the body from the horizontal surface, the push-button returns to the " on " 105 position, causing the lamp to light, and thereby illuminating the arrow 13 and projecting an image of it in the desired direction When the spotlight is released it returns to its rest position with the barrel 110 vertical and the lamp switched off. It will be seen that in operation of the spotlight the image of the arrow may be directed easily on to any part of a vertical screen, whilst the body 1 of the spotlight 115 remains resting on the horizontal surface, merely by rocking or turning the body on its spherical surface, and the image may be held steady on any desired part of the screen for quite long periods of time without undue 12) effort Also any desired inclination of the image of the arrow on the screen can readily be obtained by suitably rolling the spherical surface of the body of the spotlight on the horizontal surface: It will be appreciated that, for automatically breaking the lamp circuit when the spotlight is in the rest position, other types of switch, for example a mercury switch may be employed in place of 130 4 An electric spotlight according to

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* GB785119 (A)

Description: GB785119 (A) ? 1957-10-23

Pressure sensitive adhesives

Description of GB785119 (A) Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

/'1: 7 9;> Z r -_, _c,,, i Ly A PATENT Inventor: LEVAN LLEWELLYN Date of filing Complete Specification Sept 5, 1955. Application Date Sept 23, 1954. -Complete Specification Published Oct 23, 1957. Index at Acceptance:-Class 2 ( 6), P 4 (A: C 14 A), P 4 D 3 B( 1: 3), P 4 K 4. International Classification: -C 08 f COMPLETE SPECIFICATION Pressure Sensitive Adhesives We, THE DISTILLERS COMPANY LIMITED, a British Company, of 12, Torphichen Street, Edinburgh 3, Scotland, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - The present invention relates to pressure sensitive adhesives and to their aqeuous dispersions It particularly relates to adhesives which are pressure sensitive at normal ambient temperatures, There is at present a wide market for permanently tacky and pressure sensitive adhesives and hitherto such adhesives have been prepared by adding plasticisers, solvents and tackifiers to resinous materials such as polybutadiene and butadiene-styrene synthetic rubbers of the G R S type While it has been possible to produce acceptable pressure sensitive adhesive compositions by the addition of plasticisers and the like to -such resins, these adhesives suffer from the serious

disadvantage that they tend to deteriorate on storing due to the loss of plasticiser and their other more volatile components. An object of the present invention is to provide pressure sensitive adhesive compositions which are homogeneous and from which pressure sensitive films can be made without the addition of any plasticisers, solvents of other components which may be lost from the final compositions on storing It has now been found that certain polymers and-copolymers of certain vinyl esters of aliphatic acids give films which are pressure sensitive and tacky at normal ambient temperatures These polymers and copolymers consist of polymer chains which may be regarded as having the following type of structural formulae:-CH,2-CH-CH 2-CH-CH,-CH-CH 2 O.COR 1 O COR 2 -0 COR 3 where R,, R 2 and R, etc represent alkyl groups which may be the same or different R 1 COOH, R 2 COOH, RCOOH etc are the aliphatic acids from which the vinyl esters-are derived. If such a polymer or copolymer consists of M, molecular units derived from the ester having the formula CH,=CH O COR 1 and of M 2 molecular units derived from the ester CH 2 =CH O COR 2 etc and the alkyl groups R 1 and R 2 etc contain nr and N 2 carbon atoms respectively, then it will give pressure sensitive and tacky films if the sum of the products of the molcular units multiplied by the number of carbon atoms inthe alkyl group of that unit, i.e 2 Mn, divided by the total number of molecular units in -the polymer is equal to or greater than 2 This may be expressed in the equation M Mn: for polymers or copolymers with suitable adhesive properties These will hereinafter be referred to as vinyl ester polymers. Accordingly, the present invention provides a: process for the production of homogeneous, substantially permanently adhesive films which comprises forming the-films from an aqeuous dispersion of a vinyl ester polymer having a o Mn value for the expression, as hereinM before defined, which is equal to or greater than 2 and wherein the vinyl ester is derived from an aliphatic carboxylic acid containing from 2 to 16 carbon atoms. The films of the present inventidn may be 7. formed on suitable surfaces by any of the techniques well known in the art such as brushing or spraying the aqueous dispersion of the vinyl ester polymer on the surface and allowing the water to evaporate therefrom The 84 vinyl ester polymers and copolymers according to the present invention have high adhesive properties at normal room temperatures and therefore may be used to form useful adhesive coatings on most surfaces including, for 8 SPECIFICATION 785,119 No 27569/54. instance, paper, cloth, synthetic sheeting, glass mechanical strengths are reduced By choosing 60 and metal surfaces different vinyl esters

or altering the relative The polymer dispersions are prepared by amounts of the different esters employed, the polymerising in aqueous emulsion a resultant film can be made to have any required suitable vinyl ester or mixture of such degree of tackiness and mechanical strength. esters Most siutably the aqueous dispersions For instance, pure polyvinyl propionate gives 65 used in the process of the present invention hard films which produce very strong bonds have a solids content within the range 65 when used on paper surfaces while a copolymer % and dispersions of approximately 50 % derived from equal proportions by weight of solids are particularly valuable It is often con vinyl acetate and vinyl laurate gives a resultant venient to prepare polymer dispersions by film which is permanently tacky while still 70 polymerising an aqueous suspension contain having excellent adhesive properties Such a ing a relatively high proportion of suitable vinyl acetate vinyl laurate copolymer is admirvinyl esters and then diluting the resultant dis ably suited for the production of adhesive tapes persion with water before using it for the pre for packaging purposes. paration of adhesive coatings -The process of the present invention gives 75 The aqueous emulsion polymerisation of the rise to clear, colourless films and has the appropriate vinyl esters is brought about by' advafitage that-no inflammable or expensive any of the emulsion polymerisation processes solvents or other added components are well known in the art Most suitably the vinyl necessary. ester monomers are dispersed or emulsified The following examples illustrate the pro 80 throughout an aqueous phase containing as duction of polyvinyl ester dispersions and the dispersing agent a high molecular weight production therefrom of pressur sensitive films. hydrophilic colloid such as methyl cellulose, The parts, unless otherwise stated, are by benzyl cellulose, -various natural gums and weight. other natural materials anda polyvinyl alcohols, for instance, such as are obtained by the partial EXAMPLE 1 85 hydrolysis of polyvinyl acetate In conjunction A polymer dispersion depositing a pressure with such dispersing agents it is often desirable sensitive adhesive film may be produced as to employ anionic surface-active agents such follows: as the sulphates and sulphonates of various: organic radicals '"Aeros 6 ol OT "which is the 65 parts water sodium salt of thesulphoiic acid of dioctyl 2 _ 4 parts polyvinyl alcohol 90 succinic ester, is a typical example "Aerosol" 0,9 parts fatty alcohol-ethylene is a Registered Trade Mark The usual poly oxide condensate merisation catalysts, such as the persulphates O A 5 parts sodium salt of a suland peroxides, are employed phated oil (Calsolene

Oil The vinyl ester or esters to be polymerised H S "Calsolene" is a 95 are chosen from the vinyl esters of those ali Registered Trade Mark) phatic acids haying from 2 to 16 carbon atoms i 0 6 parts sodium hexametain the molecule If vinyl acetate is employed phosphate it has to be mixed with a sufficient quantity O 16 parts ammonium persulphate of at least one vinyl ester of a carboxylic acid 65 parts vinyl propionate 100 having at least 4 carbon atoms in its molecule so that the resultant copolymer shall have a The aqueous solution A is first prepared by votarih esk Nou&shl have a Mn heating the various components to 90 CThe value for the expression which is equal polymerisation is then carried out by the conM current addition of the catalyst and the vinyl to or greater than 2 A homogeneous polymer propionate, while retaining the reaction mix 105 of vinyl propionate has a value for the expres ture at 90 C until p Plvmerisation is comof -inyl ppintealufrhepleted The polymer dispesion is then cooled X sion of 2 and it is found that it gives and neutralised The polymer has a value for XM:: Mn films which are adhesive and pressure sensitive the expression of 2. The properties of the films formed accord 2 M ing to the present invention vary according to When the product is applied to paper and 110 Y Mn the film allowed to dry, a coating is deposited the value of-the expression Polymers which is only very slightly tacky, but which -;M gives a strong adherent bond when two such or copolymers with values near 2 give pressure surfaces are pressed together at room temperasensitive adhesive films which are not very ture 115 tacky but which form bonds having great Examples 2 and 3 show the versality of mechanical strength; As the value of the adhesive films produced from vinyl esters expression is increased the resultant films are when copolymerised in varying proportions. softer, more flexible and more tacky, but their 785,119 785,119 EXAMPLE 2. parts water parts polyvinyl alcohol A 2 parts fatty alcohol ethylene oxide condensate 2 parts sodium alkyl benzene > sulphonate 1.2 parts ammonium persulphate 126 parts vinyl acetate 54 parts vinyl laurate The polymerisation process used in this example is similar to that used in Example 1; the monomer mixture and catalyst again being added concurrently to the aqueous solution A whilst maintaining the temperature at 900 C, until the copolymerisation is substantially complete The resultant copolymer has a value :Z Mn for the expression of 2 4. EM The copolymer dispersion deposits a clear continuous film of similar characteristics to that produced in Example 1. EXAMPLE 3. This example is indentical to Example 2, except that the vinyl acetate

and vinyl laurate are used in equal quantities by weight This copolymer dispersion deposits a film, on drying, which is permanently tacky and exhibits excellent adhesion to the skin, glass and metals in addition to paper and fibrous materials In this case the copolymer has a value for the Y Mn expression of 3 75. EXAMPLE 4. A copolymer dispersion is prepared in the following manner from vinyl acetate and vinyl butyrate. 42 parts water 1.1 parts polyvinyl alcohol A 0 45 parts fatty alcohol ethylene oxide condensate 0 45 parts sodium alkyl benzene sulphonate 0.37 parts ammonium persulphate B 18 parts vinyl acetate 27 parts vinyl butyrate C Ammonium hydroxide solusolution The charge A is dissolved by heating to 900 C and then the mixture of monomers and catalyst are added concurrently over a period of three hours whilst maintaining the temperature at 90 C Heating is continued until the copolymerisation is substantially completed. The resultant copolymer had a value for the X Mn expression of 2 06. EM The copolymer dispersion deposited a 55 clear, continuous and tacky film When tested at a room temperature of 75-80 F a dried film of the copolymer deposited on paper was pressure sensitive and it was possible to produce good adhesive bonds between the surfaces 60 of the coated paper simply by the application of pressure by hand. Repetition of the process of Example 4 using only 22 parts of vinyl butyrate gives rise to a copolymer which has a value for the expression 65 Y Mn of 1 96 This copolymer gives rise to similar films on coated paper to those described above but they are not pressure sensitive and it is not possible to form good adhesive bonds between the coated paper surfaces at 70 room temperature by the application of pressure by hand. Similarly a copolymer prepared by the process of Example 4 in which 36 parts of vinyl acetate and 9 parts of vinyl myristate are 75 employed, gives rise to films which are not pressure sensitive In this case, the value for Mn is 1 94.


* GB785120 (A)

Description: GB785120 (A) ? 1957-10-23

New monoazo dyestuffs derived from cyanuric chloride

Description of GB785120 (A) Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION Inventor: WILLIAM ELLIOTT STEPHEN Date of filing Complete Specification: Nov 9, 1955. I 5,Application Date: Nov 29, 1954, Nc : E DComplete Specificatlon Published: Oct 23, 1957. Index at acceptance:-Class 2 ( 4), G, P( 1 A 3: 1 F 4: 9 A 3 A 4). International Classification:-C 09 b. COMPLETE SPECIFICATION 785,120 ? 34498/54. New Monoazo Dyestuffs Derived from Cyanuric Chloride We, IMPERIAL CHEIMICAL INDUSTRIES LIMITED, of Imperial Chemical House, Millbank, London, S W 1, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to new monoazo dyestuffs and more particularly it relates to new monoazo dyestuffs which are valuable for the production of fast orange colourations on cellulosic materials. In United Kingdom Specification No. 209,723 there is described the manufacture of azo dyestuffs by synthesising dyestuffs containing one or more cyanuric nuclei, ( 1) by uniting together or with other suitable components by reactions which lead to the formation of azo dyestuffs, intermediate products containing one or more lcyanuric nuclei, or ( 2) by uniting azo dyestuffs containing appropriate groupings, either to each other or to

other complexes, radicals or suitable residues by reaction with the halogen of cyanuric halides. In the said specification there are disclosed monoazo dyestuffs, wherein there are attached to the triazine ring two chlorine atoms and which rare obtained by reaction of one molecular proportion of an 'aminonaphthol sulphonic acid with one molecular proportion of cyanuric chloride and subsequently treating the product with a diazo compound obtained by diazotising for example aniline, p-toluidine, p-aminoacetanilide or m-xylidine There are also disclosed monoiazo dyestuffs, wherein there are attached to the triazine ring one chlorine atom and one anilino group, and which are obtained by reaction of one molecular proportion of an aminonaphthol sulphonic acid and one molecular proportion of aniline with one molecular proportion of cyanuric chloride and subsequently treating the product with a diazo compound obtained for example by diazotising aniline or a substitution product of aniline having a negative substituent, for example C 1, CO> Ror SOH, or m-xylidine or a monosulphonated naphthylamine. There is no compound disclosed in the said specification, however, which contains attached 50 to the triazine ring, in addition to two atoms of chlorine, the residue of an aminonaphthol sulphonic acid coupling component to which is attached the residue of a diazo component of the benzene series which contains suiphonic 55 acid groups. We have found that certain monoazo dyestuffs of the kind containing two chlorine atoms attached to the triazine ring and also an aminonaphthol sulphonic acid radical containing an 60 ortho-sulphophenylazo substituent, which dyestuffs in their free acid form are represented by.the formula given below have superior tinctorial value and superior fastness to wet treatments, as compared with monoazo dyestuffs of 65 comparable shade specifically described in United Kingdom Specification No 209,723 containing only 1 chlorine atom attached to the triazine ring and superior fastness to light as compared with monoazo dyestuffs of com 70 parable shade specifically described in United Kingdom Specification No 209,723 which contain two chlorine atoms attached to the triazine ring but which do not contain the ortha-sulphophenylazo substituent, when the dyestuffs are 75 applied to cellulosic textile materials by a process which comprises impregnating the said textile materials with the dyestuff in aqueous solution and subsequently subjecting the textile mateial to the action of an acid-binding 80 agent in aqueous medium for a short time, of the order of only a few minutes, advantageously in the presence of an electrolyte such as sodium chloride or sodium sulphate. According to our invention we provide new 85 monoazo dyestuffs which

in the form of their free acids are of the formula:SO 3 H O HO 3 S m R S FC / 17 iii,,aid e wherein the benzene nucleus A optionally bears further substituents other than hydroxyl and amino groups, X stands for a hydrogen atom or a substituent other than halogen, and R stands S for a hydrogen atom or for an alkyl radical. According to our invention we also proyide a process for the manufacture of the said new monoazo dyestuffs which comprises diazotising a primary aromatic amine of the formula: s H t NE Hz tit,, wherein X has the meaning stated above and the benzene nucleus may optionally bear-further substituents other than hydroxy and amino groups, and coupling the diazo compound thus formed with a coupling component of the formula: =. O H y N % c A 03-'l,= _ % 4 -0 Cl wherein -R has the meaning stated above According to a further feature of our invention we provide an alternative process for the manufacture of th Je said new monoazo dyestuffs which comprises-rea Cting a monoazo compound which, in the formiof its free acid, is of the formula 503 O N wherein X anda R have the meafings stated above and the benzene nucleus A miay optiofially bear further substituents other thafi hydroxyl and amino groups, with oine molecular proportion of cyanuric ch 16 ride As prifiary aromatic airlines' which may be used in the process of -our inventi 6 N thereixmay be mentioned aniline-2-sulplioiitd cid, aniline 2: 5-disulphonic acid, 2 -4 dimethylaniline-6silphonic acid, 3-aniinobeizotfifluioridd-4 sulph 6 ic ac'id, 4-chloro-5-methylaniline-2-sul'phonic acid, 5-chloiof 4-methylanilin&-2-sulphonic acid, 3-acetylaminoaniline-6-sulphonic acid, 4-acetylaminoaniline-2-iulphonic acid, 4chloroaniline-2-sulphonic acid,; 3: 4-dichloroaniline-6-sulphonic acid, 4-methylaniline-2sulphonic acid, 3-methylanilinez 6-sulphonic acid, 2:4-dimethoxyaniline-6-sulp'honic acid, 4methoxyaniline-2-sulphonic acid and 5methoxyaniline-2-sulphonic acid. As coupling components for use in the azo coupling process of our invention there may be used for example the primary condensation products obtained by reaction of 2-amino-5naphthol-7-sulphonic acid, or derivatives of 2 50 amino-5-naphthol-7-sulphonic acid containing an alkyl radical as a substituent in the amino group, with one molecular proportion of cyanuric chloride in aqueous medium. The monoazo compounds used as starting 55 materials for reaction with cyanuric chloride by the alternative process of our invention may be obtained by diazotising a primary aromatic amine, as defined above, and coupling the diazo compound thus obtained in alkaline 60 medium with a coupling component of the formula:Oil CHR HO 35 wherein R has the meaning stated above, or alternatively, when the said diazo compound 65 does not contain an acylamino group, by coupling the said

diazo compound in alkaline medium with the N-acyl derivative of such a coupling component and subsequently removing the acyl group by hydrolysis with for ex 70 ample caustic soda In the process of our invention, the diazotising of the amino compound and the coupling of the diazo compound thus produced with the coupling compohent is preferably carried out 75 at a temperature' below 5 C, conveniently at 0-5 C -In the process of our invention wherein there is used a coupling component containing the cyanuric nucleus it is advantageous to use for the coupling reaction the 80 said coupling component prepared in situe at temperatures of O 5 C by methods known from the literature and to carry out the couplings at similar temperatures and at as low a p H as is possible for efficient coupling, in order 85 that side reactions, for example hydrolysis of the chlorine atoms remaining attached to the triazine ring, are minimised. Similarly, in order to avoid such side-reactions during manufacture and storage it is 90 generally preferable to isolate the new dyestuffs from the media in which they have been formed at a p H from 6 4 to 7 8 and to dry the resultant dyestuff pastes -at relatively low temperatures, for example between 20 and 40 C, prefer 95 ably in thepresence of buffering agents suitable for maintaining a p H value of about 6 5 Examples of such-buffering agents are mixtures of disodium hydrogen phosphate and sodium dihydrogen phosphate or of disodium hydrogen 100 phosphate and potassium dihydrogen phosphate In the manufacture of -the new dyestuffs of the invention by the said alternative process namely by reacting equimolecular proportions 105 of a monoazo compound of the formula stated and cyanuric chloride the reaction is preferably carried out in aqueous medium at temperatures 785,120 mixture is stirred for 30 minutes, while the temperature is maintained between O and 4 C., and the mixture is filtered, and the solid on the filter is washed with 20 % brine and then with acetone and dried at 20 to 45 C The product forms a red-brown solid which dissolves in water to give an orange solution and in concentrated sulphuric acid to give a bluish red solution between O and 5 C. The new dyestuffs of this invention in the form of their alkali metal salts are readily soluble in water and are especially suitable for the production of level and fast orange colourations on cellulosic textile materials by continuous dyeing techniques, for example by a process which comprises impregnating the said textile materials with a solution of the dyestuff -and thereafter subjecting the textile materials, opionally after drying, to the action of an acidbinding agent for example caustic soda, in aqueous medium which advantageously contains an electrolyte such as sodium chloride or sodium sulphate, for a short period of time, commonly of the order of only a few minutes, at temperatures conveniently lying between atmospheric

temperature and the temperature of the boiling solution, and also by printing methods, for example by a process which comprises applying to the said textile materials a printing paste containing the dyestuff and a substance which on heating or steaming liberates an acid-binding agent, for example sodium bicarbonate, and subsequently subjecting them to the action of heat or steam The colourations thus produced possess a very good fastness to light and a high degree of fastness to wet treatments, especially to repeated washing. The invention is illustrated but not limited by the following Examples in which the parts are by weight: EXAMPLE 1. A solution of 18 5 parts of cyanuric chloride in 100 parts of acetone is poured into a stirred mixture of 400 parts of water and 400 parts of crushed ice, and 2 parts of 2 N hydrochloric acid are added To the suspension of cyanuric chloride thus obtained there are added during 40 minutes, and at a temperature below 50 C, 26.1 parts of the sodium salt of 2-amino-5naphthol-7-sulphonic acid as a solution in 480 parts of water, made faintly alkaline to Brilliant Yellow by the addition of sodium carbonate. The mixture is stirred at a temperature below C for 1 hour and then 6 parts of 2 N sodium carbonate solution are added and stirring is continued at the same temperature for another minutes A suspension of the diazo compound from 16 45 parts of aniline-2-sulphonic acid, obtained by diazotising the aniline-2-sulphonic acid in a mixture of 200 parts of water and 18 parts of hydrochloric acid (specific gravity 1 18) at a temperature between O and 2 C with 6 55 parts of sodium nitrite, is then added to the mixture during 5 minutes at a temperature between O and 4 C 40 parts of sodium acetate crystals are added during 10 minutes and the mixture is stirred at 0 to 4 C for 90 minutes, after which time sufficient anhydrous sodium carbonate is gradually added during a further 90 minutes to render the aqueous medium slightly alkaline to litmus. Sufficient sodium chloride to give a concentratihn of 200 grams per litre is added and the EXAMPLE 2 75 An alternative method for the preparation of the dyestuff described in Example 1 is as follows: 18.5 parts of cyanuric chloride are dissolved in 100 parts of dry acetone and the solution is 80 added gradually with stirring to a mixture of 300 parts of water and 400 parts of crushed ice. To the stirred suspension of cyanuric chloride so formed there is added during 40 minutes a solution in 800 parts of water at 20 C of 46 7 85 parts of the disodiurnmsalt of the aminoazo com pound which is formed by coupling diazotised 2-aminobenzene sulphonic acid with N-acetyl 2-amino-5-naphthol-7-sulphonic acid in the presence of sodium carbonate, purifying the 90 product to remove from it any dyestuff

formed by coupling on the 8-position of the N-acetyl 2amino-5-naphthol-7-sulphonic acid, and hydrolysing to remove the acetyl group by heating it in an aqueous solution containing about 4 % 95 caustic soda at 80-85 C. The temperature of the reaction mixture is maintained between O and 4 C and within a few minutes of completing the addition of aminoazo compound none of it remains un 100 changed The acid solution formed is made neutral to litmus by the addition of sodium carbonate solution and there is also added to it a solution containing 7 parts of anhydrous disodium hydrogen phosphate and 125 parts of 105 anhydrous potassium dihydrogen phosphate in parts of water Sufficient salt to give a concentration of 100 grams per litre is added, and the mixture is stirred for a short time and is then filtered The solid is mixed intimately 110 with 4 2 parts of anhydrous disodium hydrogen phosphate and 7 5 parts of anhydrous potassium dihydrogen phosphate and dried at 20 C If the aminoazo compound used for conden 115 sation with cyanuric chloride in this Example is replaced by an equivalent amount of one of the aminoazo compounds named in the list below and prepared in each case by coupling a diazo compound obtained from a derivative of 120 aniline-2-sulphonic adcid with an N-acyl-2amino-5-naphthol-7-sulphonic adcid, for example N-acetyl-2-amino-5-naphthol-7-sulphonic acid or an N-acyl-N-substituted 2amino-5-naphthol-7-sulphonic acid, for ex 125 ample N-acetyl-N-methyl-2-amino-5-naphthol7-sulphonic acid and removing if necessary any product formed by coupling on the 8-position of the 2-amino-5-naphthol-7-sulphonic acid residue and then hydrolysing the purified 6 130 785,120 coupled product by heating with caustic soda in aqueous solution, then the alternate dyestuffs formed all have the capability of giving bright -colourations on cellulosic materials for example cotton, when applied from aqueous solutions by padding and after-treating the padded material, optionally after drying with Aminoazo compound reacted with cyanuric 4-Toluidine-3-sulphonic acid diazotised and coupled with 2-amino-5-naphthol-7-sulphonic acid 5-chloro-4-methyl-2-aminobenzene-sulphonic acid diazotised and coupled with 2-amino-5-naphthol7-sulphonic acid 4-chloroaniline-2-sulphoniic acid diazotised and coupled with 2-amino-5-naphthol-7-sulphonic acid Aniline-2:5-disulphonic acid diazotised and coupled with 2-amino-5-naphthol-7-sulphonic acid Aniline-2-sulphonic acid diazotised and coupled With N-methyl-2-amino-5-naphthol-7-sulphonic acid 4-chloro-5-methyl-2-aminobenzenesulphonic acid diazotised and coupled with 2-amino-5-naphthol7-sulphonic acid 3-aminoanisole-4-sulphonic acid diazotised and coupled with 2-amino-5-naphthol-7-sulphonic acid 3-toluidine-4-sulphonic acid diazotised and coupled with 2-amino-5-naphthol-7-sulphonic acid

Aniline-2-sulphonic acid diazotised and coupled with 2-n-butylamino-5-naphthol-7-sulphonic acid


* GB785121 (A)

Description: GB785121 (A) ? 1957-10-23

Improvements in or relating to magnetic recording tapes


t P Auh Nt SP-1 Ci FICATPIO Inventor: WILLIAM SOBY Date of filing Complete Specification Nov 3, 1955. Application Date Dec 3, 1954. Complete Specification Published Oct 23, 1957. Index at acceptance: -Class 40 ( 2), A 1 C 3. International Classification: -CI O j. COMPLETE SPECIFICATION 785,121 No 34996154. Improvements in or relating to Magnetic Recording Tapes We, ELECTRIC & MUSICAL INDUSTRIES LIMITED, a British company, of Blyth Road, Hayes, Middlesex, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to magnetic recording tapes of the kind comprising a flexible base having an adherent laver of magnetisable material applied to one side thereof in such a manner as to produce a relatively smooth surface For example, a tape of this kind may comprise a base of polyvinyl chloride about 002 " in thickness and

about 4 " in width, provided with an adherent layer comprising very finely divided gamma-phase ferric oxide and a suitable binding medium, said coating being about 0005 " in thickness. 2 (' A tape of the kind referred to, which may be many hundreds of feet in length, is usually stored by winding it on a supply reel or spool, and during a recording or reproducing operation, suitable apparatus is employed to unwind the tape from the supply reel and to wind it on to a take-up reel at a relatively slow speed such as 72 " per second At the end of the recording or reproducing operation it is generally necessary to rewind the tape back on to the supply reel and in order to save time it is desirable for the re-winding operation to take place at a high speed which may be ten or more times as fast as the recording or reproducing speed. Circumstances may also arise in which it is necessary to wind the tape from the supply reel to the take-up reel at a similar high speed It is found that when a tape of the kind referred to is reeled at high speed there is a tendency for some of the wound turns to be forced out of the general plane of the wound tape, and even if some of the wound turns are not forced out completely, the-tape is liable to wind unevenly Consequently, it has been necessary heretofore to limit the speed of windingu in order to prevent the aforementioned undesirable effects It is believed that when a tape of the kind referred to is wound at too high a t Piice, 3 s 6 d l speed air is trapped between the wound convolutions and as pressures in a radially inward direction is built up by the succeeding con 50 volutionsi, a point is reached at which the trapped air is forced to escape thereby causing displacement of some of the wound turns in a direction substantially perpendicular to the plane of the wound tape 55 The main object of the present invention is to provide a magnetic recording tape which can be wound satisfactorily especially at high speeds. Accordingly the invention provides a mag 60 netic recording tape comprising a flexible base having on the front surface thereof a continuous smooth adherent layer of magnetisable material, and on the rear surface thereof a raised pattern affording narrow passages which 65 extend to at least one of the edges of said tape, said passages having a depth sufficient to allow the escape of air which in the absence of said passages would tend to be trapped between the convolutions of said tape when 70 wound. In order that the invention may be clearly understood and readily carried into effect several embodiments thereof will now be des cribed with reference ito the accompanying 75 drawings in which:Figure 1 is an enlarged view of the rear surface of a piece of magnetic recording tape, provided with one form of raised pattern according to the invention; 80 Figure 2 is a cross-section, not to scale, on the line

A-A of Figure 1; Figures 3, 4 and 5 are enlarged views similar to Figure 1 showing pieces of tape pro vided with raised patterns of different forms; 85 Figure 6 is an enlarged view similar to Figure 1 showing a piece of tape provided with another different form of raised pattern, and Figure 7 is a cross-section, not to scale, on the line B-B of Figure 6 90 The magnetic tapes illustrated comprise a flexible base 1 for example of polyvinyl chloride, cellulose acetate, or a polyester resin such as those known by the ( f 7 , ' ' , 1,, ", o_ J ' 1 1 785,121 i Registered Trade Marks as -Mylar and Melinex, the base-1 having a thickness of about 002 " or less and a width of about 4-" The front surface of the base 1-carries a smooth continuous adherent layer 2 of magnetisable material which may comprise very finely divided particles of gamma-ferric oxide and a suitable binding medium The layer 2 may have a thickness of about 0005 " or less and the exposed surface thereof is preferably rendered as smooth as possible for instance by means of a polishing or calendering operation In accordance with the invention, the rear surface of the tape, which is initially smooth, is provided with a raised pattern preferably by means of a printing operation. In the example illustrated in Figures 1 and 2 the raised pattern is in the form of small separated squares 3 having sides about 1/20 " -in length which are arranged obliquely with respect to the longitudinal edges 4 and 5 of the tape and preferably at 45 thereto The squares 3 are arranged so as to leave two intersecting sets of narrow uncoated channels 6 -and 7 which are preferably rectilinear and which cross each other at right angles, the channels 6 and 7 providing escape passages extending to both edges 4 and 5 of the tape. The uncoated channels 6 and 7 are approximately 015 " in width. The examiple illustrated in Figure 3 is simi:lar to that of Figure 1 except that the raised pattern is in the form of bars 8 arranged at less than 90 and preferably at approximately 450 to the edges 4 and 5 of the tape, the bars 8 being spaced and parallel to each other so as to leave narrow uncoated rectilinear channels 9 which provide the aforementioned escape passages extending to both edges 4 and 5 of the tape Alternatively as shown in Figure 4 the raised pattern may be in the form of curved bars 10 leaving narrow uncoated curved channels 11 extending to both edges 4 and 5 of the -tape However it is not essential for the escape passages to extend to both edges of the tape, and in the example illustrated in Figure 5 the raised pattern is so arranged as to leave narrow -uncoated channels 12 extending only to the edge 4 of the tape and similar uncoated channels 13 extending only to the other edge of the tape, the channels 12 and 13 being -positioned alternately along:the tape In the case of escape passages which do not extend -from edge to edge of the tapes it is desirable

-that they should extend at least from one edge to the longitudinal centre line of the-tape. T The raised pattern provided in accordance with the invention may take numerous forms -other than those illustrated in the drawings. Thus, the pattern may consist of diamonds, or rectangles or, in fact, it may be arranged in -any manner consistent with the provision of -the narrow escape passages extending to at least one edge of the tape. In the examples illustrated in Figures 1 to the escape passages are formed by uncoated portions of the rear surface of the tape, but as shown in Figures 6 and 7 the raised pattern may be formed by providing the rear surface of the tape with a coating comprising an overall layer and a further layer which extends over only selected portions of the overall layer so as to leave escape passages formed by regions of the coating which are thinner than the remainder thereof Thus as shown in Figure 7 the initially smooth rear surface of base 1. having a smooth adherent layer 2 of magnetisable material on the front surface thereof, is provided with a coating which exhibits narrow escape passages formed by narrow coated regions 14 of reduced thickness which extend to at least one of the edges 4 and 5 of the tape, and preferably extend from edge to edge of the tape as shown in Figures 6 and 7. The raised pattern may be printed on the rear surface of the tape with an ink which may comprise a suitable resin or resins such as polyvinyl chloride polymers, a proportion of plasticizers including a non-migratory type, a proportion of pigments and an anti-blocking agent, the whole being dispersed in a suitable solvent A preferred ink which has been employed successfully as the printing medium was made up in accordance with the following formula: % by weight A tripolymer of vinyl chloride, vinyl acetate and interpolymerised maleic acid such, for example, as that known by the Registered Trade Mark "Vinylite " Resin VMCH manufactured by Bakelite Ltd U S A 9 22 A tripolymer of vinyl chloride, vinyl acetate and vinyl alcohol, such, for example, as that known by the Registered Trade Mark "Viny-lite" Resin VAGH manufactured by Bakelite Ltd, U.S A 4 61 Dioctyl phthalate 1 38 A polymeric plasticizer such as that known by the Registered Trade Mark "Reoplex" R 100 which is a polypropylene sebacate, manufactured by Geigy Ltd, London, England 0 59 Carnauba wax 0 21 Fine silica powder such as "Superfloss" manufactured by Johns Manville Ltd London, England 2 79 Titanium dioxide 0 28 Black dye 0 37 Butyl acetate 80 55 The raised pattern whether formed by a printing operation or in any other suitable way, 785,121 preferably has a thickness of the order of " to 0001 ", and care must be taken to ensure that no appreciable curling of the tape is caused either during

or after the applicaS tion of the raised pattern In this respect it is advantageous to make the pattern discontinuous as shown for example in Figure 1. The aforementioned escape passages have been described as being narrow, and this definition is to be taken to mean that the width of said escape passages is such that when the tape is wound on to a reel or spool, very little if any distortion of the wound tape is produced as a result of the presence of said escape pas-15 sages Thus in general it is preferred that the area of the rear surface of the tape occupied by the escape passages shall be small as compared with the total area of said rear surface. In the manufacture of magnetic recording tapes it is usual to commence with a relatively wide base which is provided with an overall layer of magnetisable material and then slit into a number of tapes of the required width The provision of a raised pattern on the rear surface of the tape according to the invention, can be effected before or after the slitting operation; or before, after or simultaneously with the coating of the front surface with magnetisable material. It is found that a magnetic recording tape according to the invention can be reeled at high speed without the deleterious effects thought to be caused by air being trapped between the wound convolutions of the tape, because the aforementioned escape passages provide means whereby any air which tends to be trapped between the wound convolutions can escape to the atmosphere Thus, considerable time can be saved since reeling operations can tale place satisfactorily at higher speeds -than heretofore. The term " magnetic recording tape " used -herein is intended to include tapes already provided with recordings such as might be sold to the public only or mainly for reproduction of the recorded matter in the same manner as conventional gramophone records.


* GB785122 (A)

Description: GB785122 (A) ? 1957-10-23

Improvements in gate or door operating devices


PATENT SPECIFICATION k Date of filing Complete Specification: Feb 6, 1956. SD D 4 Applicafion Date: Feb 8, 1955 No 3702/55. Complete Specification Published: Oct 23, 1957. Index at Acceptance:-Class 65 ( 1), A'2 A: 3: 5). International Classification:-E 051. COMPLETE SPECIFICATION. Improvements in Gate or Dooi Operating Devices. I, G Eo FFREY C Ross LEY, of 4 Rooms Lane, Morley, in the County of York, a British Subject, do hereby declare the invention for which I pray that a Patent may be granted to me, and the method by which it is to be performed, to be described in and by the following statement:- This invention relates to devices for operating swinging or sliding gates or doors all of which are hereinafter included in the term " gates " Many gates of the above type, particularly the heavy kind, require means for operating them and some of these are of a complicated construction Gates often require one or more runners engaging the ground, floor or other surfaces (hereafter termed " floor ") but these are normally free-running devices merely to take some of the weight of the gate and with swinging gates are mounted at the bottom near the outer edge In some cases these wheels run on or in a track In many instances it is desirable to have means which serve to support the gate and also means to operate it during its opening and closing movements and the main object of this invention is to provide a simple form of self-contained unit which is electrically driven for operating a gate. Accordingly there is provided a gateoperating device, comprising a unit adapted to be mounted on the face of a gate, including a drive wheel to run on a bearing surface, such as the ground, a floor, guide track or other surface and having a drive shaft, and an electric motor for driving the shaft through worm gearing, whereby, in use, on the motor being energised the wheel will be rotated and its frictional engagement with the bearing surface operates the gate The electric motor may be of the reversible type. The improved unit may have a slide mounting plate to alow relative movement lI between unit and gate Spring-loading means may provide a

resilient connection in this mounting The drive wheel may be adapted for disconnection from its drive shaft, should a power failure occur. Referring now to the accompanying drawings in which several embodiments of the invention are shown:Fig 1 is a perspective view of a gate with a gate-operating device of the ground engaging type; Fig 2 is a front detail elevation of the device with its cover removed; Fig 3 is a side elevation of Fig 2; Fig 4 is a plan view of a mounting plate for the device; Fig 5 is a front elevation of a modified ground engaging device; Fig 6 is a side elevation of Fig 5; Fig 7 is a plan view from above of the device; and Fig 8 is a part sectional view of a gateoperating device adapted for a sliding gate with the wheel running on a top guide track. In a particular embodiment of this invention shown in Figs 1, 2 and 3, a gateoperating device 1 is constructed in the form of a comparatively small self-contained unit adapted to be mounted on one face of the gate 2, adjacent the juncture of its lower and outer edges The unit includes a drive shaft 3 mounted in bearings 4 provided in a carrier framework 5 with a worm wheel 6 keyed or otherwise secured on the shaft towards one end thereof Above this worm wheel and shaft is mounted a countershaft 7 carrying a worm 8 in mesh with the worm wheel and this countershaft lies at right angles to the driving shaft which lies parallel with the face of the gates when mounted. The carrier framework provides a platform 9 for a reversible electric motor 10 of the required horse-power and any convenient drive means, such as V-pulleys 11 and a belt 785,122 65. c 785,122 12, are used to connect the motor to the countershaft. On the driving shaft is mounted a drive wheel 13 which is to bear on to the ground or a floor and thus provide frictional driving means Conveniently this wheel has a solid rubber tyre and a driving connection is provided between the wheel and driving shaft, such as a key or splines The mechanism is carried by a back plate 14 adapted to fit into the guide grooves 15 of a slide plate 16 which is screwed or otherwise secured to a gate for the mounting of the device A cover 17 is provided and has inturned flanges to slidably engage in the outer grooves 18 of the plate 16. The unit normally is free to slide relative to its mounting plate and relies on its own weight for the frictional grip of-the wheel 13 on the ground or floor This arrangement enables the unit to adjust itself to a-sloping or uneven floor and yet form a driving means for the gate On the other hand, the inuit may be spring-loaded in regard to its slide mounting plate and thus serve to tend to support the gate and take some of the load off the hinged or other means by which the gate is mounted When the unit requires to be rendered inoperative it can be raised until the wheel is clear of the ground and locking means

provided to hold it raised. A modified smaller unit is shown in Figs 5 to 7 wherein the reversible electric motor 10 has its shaft directly connected to the input shaft of a worm reduction gear box 19, which can be -oil filled The output shaft of this gear box projects at a right angle to the worm input shaft and has the drive wheel 13 secured thereon The motor and gear box are supported in resilient bearings 21 of the arms 22 extending from the back plate 23 which is slidably mounted in a slide plate 16 similar to that already described. This unit is shown with a lever 24 pivoted to the back plate 23 so that when partly rotated its lower end bears on to the top edge of the fixed slide plate 16 and thus raises the unit and retains it in an inoperative position In this mounting of the unit the clamping bands 25 of the resilient bearings may be loosened so that the motor, gear box and wheel unit may be partly turned about -the motor axis for the drive wheel to assume a different position, say for a sliding gate or door. In yet, another modification shown in Fig 8 the invention is adapted for a sliding gate or door 26 In this construction the reversible electric motor 10 is secured to a back plate 14 strengthened with angle members 14 a and having a top plate 27 on which the worm reduction gear box 28 is secured. The drive wheel 13 is secured on the output shaft 29 and bears on to a fixed guide track 30 A belt or chain 31 provides the driving connection between the motor and gear box and a cover 32 is provided for the unit. Again the weight of the slidable unit is used to hold the drive wheel firmly on the guide track 30 although a spring loading may be incorporated so that at least some of the door load may be supported Also, the unit may be adapted to be retained in an inoperative position It will be understood the electric motor may be mounted in another position to suit requirements, say carried by the gear box or secured thereto, or the platform 27, and with a belt or chain drive or direct connection. In any of the above constructions, a 80 clutch or other disconnecting means may be provided between the drive wheel 13 and its shaft For example, a catchplate is secured on the shaft and furnished with one or more parts to be driving dogs projecting 85 from part of the wheel, or the order may be reversed, i e, the dogs are on the plate, and project to engage the wheel The arrangement may be such that the wheel may be disconnected from the shaft and this can be 90 accomplished by the provision of a displaceable make-up collar between the wheel and a retaining nut or collar on the shaft end so that on release of the nut or other retaining means the wheel can be slid axially 95 on the shaft

to break the driving connection. Alternatively, quick-release means may be employed for making and breaking the driving connection The disconnection may be made by moving the wheel relative to the i O u catchplatc or the latter may be furnished with displaceable means to engage the dogs on the wheel or other complementary part. 13 y making it possible to disconnect the wheel from the driving shaft the device can 105 be rendered free-running should there be an electric power failure or other breakdown. A unit of the above type can be manufactured and mounted relatively cheaply and usually there is no need to make any altera 110 tions to an existing gate, or provide for hidden gearing or other operating means above a gate or say under floor level, or in other structures with which the gate si associated It also has the advantage that 115 in an emergency the gate could readily be forced open as the wheel would skid on the ground or floor, or as -above stated, there could be a quick disconnection of the wheel from the bearing surface or the driving 120 shaft In many cases the unit when mounted is of such a size as to be comparatively inconspicuous and the housing or shrouding means serve not only as a finish for the device but may also form a waterproof or 125 dustproof cover The motor may be energised by the provision of any known form of control means in the electric circuit, and whilst invariably it is reversible to drive in 785,122 two directions, it may be of the type to drive in one direction only.


4711 4715.output

Law