Classifications

• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/10—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
  • H05K3/105—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam
  • H05K3/106—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam by photographic methods
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/02—Electroplating of selected surface areas
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/015—Apparatus or processes for the preparation of emulsions
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
  • G03C5/58—Processes for obtaining metallic images by vapour deposition or physical development
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors

Definitions

• a lightsensitive layer which contains at least one light-sensitive compound which is converted by the reaction of light into a light-reaction product and which, as such, can be physically developed or which is capable of forming, in a secondary reaction, physically developable metal germs, the metal forming the erm image being provided, as a compound, in the layer either prior to the exposure or being added to the layer subsequent to exposure, the metal germ image formed being intensified by means of stabilized, purely physical development.
• noble-metal layers is to be understood to mean herein not only layers having an uninterrupted surface of a noble metal but also the layers having patterns having continuous or discontinuous portions, for example, station-name dials for radio apparatus, ornamental objects, printed wirings, printed circuits and so forth.
• the term purely physical development referred to above is to be understood to mean the intensification of a weak, photographic metal germ image into an image of the desired optical density or with the required quantity of image metal by treating said weak germ image with a developing solution containing photographic reducing agents, and reducible compounds of metals nobler than copper, for example, silver, gold, platinum and so forth.
• a frequently used physical developer is, for example, a solution of silver nitrate in water, to which is added metol, hydroquinone or p-phenylene diamine.
• metol, hydroquinone or p-phenylene diamine To such a developer are furthermore added, as a rule, other substances, in order to improve the preservability or to control the speed of development, for example, organic acids, butler mixtures or substances reacting with the noblemetal compound while forming complex ions.
• organic acids, butler mixtures or substances reacting with the noblemetal compound while forming complex ions for example, organic acids, butler mixtures or substances reacting with the noble
• a physical development in which use is made of th stabilizing effect of ionic, surface-active substances in conjunction or not in conjunction with a non-ionic, surface-active compound is termed herein a stabilized physical development. If the use of these surface-active compounds in the physical development is dispensed with, reference is made herein to non-stabilized physical development. Such stabilized physical development is shown in copending U.S. application Serial No. 845,098.
• a method which uses a light-sensitive layer which does not contain, during the exposure, a metal compound forming a germ image and in which, by the exposure, a light-reaction product is formed which is capable, in a secondary reaction, of setting free metal from a solution of a mercurous or silver compound.
• this method is used a special, so-called mirror exposure, after which the layer is contacted with a solution of the said metal compound (the so-called germ introduction bath), so that an at least partly external metal germ image (lying on the surface of the support) is formed, this external metal germ image, upon intensification by means of non-stabilized, purely physical development, grows into an external, electrically conductive noble-metal layer.
• the external metal germ image does not grow into an external, electrically conductive noble-metal layer, however, if it is subjected to a treatment with a stabilized, purely physical developer.
• mirror exposure is to be understood to mean that exposure energy per surface unit of the light-sensitive layer which, at the chosen concentration of metal ions in the germ introduction bath, provides an at least partly external metal germ image, which after intensification by means of a chosen non-stabilized, purely physical developer, provides, under chosen conditions of temperature and developing time, an external noble-metal layer which exhibits an electric resistance not exceeding 18 ohms per square.
• electrically conductive, noble-metal layers may be manufactured, by photographic means, on at least superficially non-metallic, electrically non-conductive, at least hydrophilized macromolecular supports, which noble-metal layers have an excellent adhesion to the support and a beautiful gloss.
• a light sensitive compound such as a silver halide or one which produces, upon exposure to light, a light reaction product capable of producing in the presence of water silver or mercury germs from water soluble silver and mercury compounds either present before or after exposure and this layer is exposed to light for a certain critical minimum exposure energy called herein the outgrowth exposure and the layer after the silver or mercury genn image is formed is developed with a stabilized physical developer for a prolonged period of time the internal image which has been formed before physical development is made to grow out beyond the surface of the support and become an external image having a resistance of less than 10 ohms per square.
• a light sensitive compound such as a silver halide or one which produces, upon exposure to light, a light reaction product capable of producing in the presence of water silver or mercury germs from water soluble silver and mercury compounds either present before or after exposure and this layer is exposed to light for a certain critical minimum exposure energy called herein the outgrowth exposure and the layer after the silver or mercury genn image is formed is developed with a stabilized physical developer for a
• a substantially only internal metal germ image is, in accordance with the invention, intensified by stabilized physical development, or else only the internal portion of a partly external metal germ image, is intensified by stabilized physical development, While initially an internal, neutrally grey to black noble-metal image is formed, which, upon a prolonged stabilized development, grows into an external, electrically conductive noble-metal layer, which exhibits an improved adhesion to the support and, as a rule, a more beautiful gloss than such a layer obtained by the method described in the copending application.
• appreciably longer developing times are, as a rule, required than in the known method.
• the method according to the invention has the great advantage that now for the manufacture, by photographic means, of external, electrically conductive noble-metal layers use may be made of stabilized, purely physical development.
• the activity of the developer is required to be accelerated in order to reduce the developing time. This may be achieved by using a higher developing temperature, by choosing higher concentrations of the noble-metal compound and/or of the photographic reducing agent in the developer, of a higher pH of the developer, and so on than is common practice for the development of normal internal images. With stabilized physical development this may, as a rule, be achieved without troublesome spontaneous formation of noble-metal germs. Owing to this activation of the developer the development into an external image can be accelerated by a factor 10 to 20.
• outgrowth exposures The exposure energies to be employed to obtain photographic metal germ images which grow, upon a prolonged stabilized purely physical development, into external, electrically conductive noble-metal layers with reproducible properties, are termed herein outgrowth exposures.
• outgrowth exposure is to be understood to mean herein that exposure energy per surface unit of the light-sensitive layer which, with a chosen photographic system and with a chosen composition of the light-sensitive layer, yields a photographic metal germ image, which, upon intensification in a stabilized, physical developer obtained by dissolving, in distilled water,
• any other stabilized physical developer is capable of providing an external, electrically conductive noble-metal layer by developing for such a long time that the resistance of the noble-metal layer is at the most 10 ohms per square.
• the physical development may be carried out, as stated above, as an alternative with aid of a stabilized, physical developer which has been activated to shorten the developing time.
• the thermal after-treatment is carried out by heating the noble-metal layer at a temperature of at least C.
• the desired effect is attained more rapidly with an increase in temperature but the effect of the temperature on the material of the support must be considered.
• the chemical after-treatment to reduce the electric resistance of external silver layers consists in bringing these into contact with an aqueous solution containing one or more compounds separating off a hydrogen ion or a potential determining anion with respect to the silver metal, for example (31 BF, J'-3, CNS CN 3, 8 803 S203: 01 OH.
• Mechanical polishing of the layer reduces, in many cases, the electric resistance of the layer to a sufficient extent. Moreover, such a treatment improves the optical decorative properties of the noble-metal layer.
• an external noble-metal layer obtained by the method according to the invention should be subjected to an electro-chemical aftei treatment, after which a superficial chemical conversion or coloration may be carried out.
• an electro-chemical aftei treatment after which a superficial chemical conversion or coloration may be carried out.
• use may be made, for example, of electrolytic polishing, electrolytic deposition of metals, while use is made or not made of an external current source, electrolytic coloration of the deposited metal or electrophoretic coating with a protective or insulating or photoand/ or semiconductive surface layer. If desired, a combination of various electro-chemical and/ or chemical after-treatments is possible.
• a few important suitable after-treatments of this kind are, inter alia: polishing of the surface, application of a lacquer or varnish layer to the layer surface, embedding of the layer, together with the support, in an insulating envelope of thermo-hardening or thermoplastic material, transfer of the layer, if necessary together with the support, to a different, support of high electrical qualities, also of thermo-hardening or thermo-plastic material, application of electrical connections by soldering (for example, dip soldering).
• the method according to the invention may, consequently, be carried out by means of all those photographic materials in which, by exposure, a physically developable metal germ image can be obtained directly or indirectly.
• These materials are, in the first place, those which contain a light-sensitive compound of which the light-reaction product behaves, as such, i.e. without previous chemical conversion, as a physically developable photographic metal germ image, for example, the materials containing, as a light-sensitive compound, silver halide.
• They include furthermore all photographic materials containing a light-sensitive compound of which the light-reaction product, as such, cannot be physically developed, this product being, however conversible, in a secondary reaction, into a physically developable, photographic metal germ image, while the metal forming the germ image is contained in the photographic layer in the form of a compound prior to exposure.
• This secondary reaction if the light reaction product is a metal compound, will consist in setting free metal germs therefrom, as is, for example, the case with the photographic process in which use is made of the light-sensitivity of the so-called Eder solution and in which the light-reaction product consists of mercurous chloride.
• An important group of photographic materials which may be employed in the method according to the invention are the materials containing a light-sensitive compound of which the light-reaction product, in a secondary reaction, is capable of setting free physically developable mercury or silver germs from mercurous or silver compounds respectively.
• This secondary reaction may be based on a so-called disproportioning of mercurous ions in accordance with the reaction equation:
• Free mercury is formed since the light reaction product reacts with mercuric ions. Or it may be based on the reduction of silver ions in accordance with the equation:
• the mercury atoms or silver atoms set free respectively unite to form mercury or silver germs respectively.
• the mercurous compound or the silver compound may be provided prior to exposure in the layer containing the light-sensitive compounds (US. Patents 2,067,690 and 2,738,272) or a solution of such a compound may be brought into contact with the layer after the latter has been exposed.
• the last-mentioned variant is termed germ introduction method and the solution of the metal compound by which the introduction of the germs is carried out is termed germ introduction bat (US. Patent 2,764,484).
• the light-sensitive compounds of the class of the aromatic diazosulphonates are particularly useful, more particularly in conjunction with so-called anti-regression agents, i.e. substances which, when added to the layer, prevent diazosulphonate from being reformed from its light-reaction product by binding either the sulphite or the diazoniurn radical or both so that the sulphite remains capable of reacting with the mercurous compound while forming mercury germs
• anti-regression agents i.e. substances which, when added to the layer, prevent diazosulphonate from being reformed from its light-reaction product by binding either the sulphite or the diazoniurn radical or both so that the sulphite remains capable of reacting with the mercurous compound while forming mercury germs
• anti-regression agents i.e. substances which, when added to the layer, prevent diazosulphonate from being reformed from its light-reaction product by binding either the sulphite or the diazon
• Suitable, light-sensitive compounds of which the light-reaction product sets free, in a secondary reaction, physically developable mercury germs from a mercurous compound, are, for example, o-hydroxy-benzene-diazo nium compounds, o-hydroxy-naphthalene diazonium compounds, aromatic diazocyanides, oand p-nitro-mandelic acid-nitril, the bisulphite compounds of oand p-nitrobenzaldehyde, a series of inorganic, complex compounds from which, by exposure, one or more of the following ions or molecules are set free:
• the light-reaction product of ohydroxy-benzene-diazonium compounds and of o-hydroxynaphthalene diazonium compounds is also capable of setting free physically developable silver germs from silver compounds.
• Suitable materials which may be used for the supports in carrying out the method according to the present invention are, in general, all film-forming high polymer products, which if not yet so, are rendered superficially accessible to a certain extent for the various baths, for example, gelatin, regenerated cellulose paper, wholly or partly saponified cellulose esters, polyvinyl alcohol, and so forth.
• Example I A superficially saponified cellulose triacetate foil was sensitized by impregnating it for two minutes in an aqueous solution containing 0.15 mol of o-rnethoxy-benzenediazosulphonic acid sodium and 0.1 mol of cadmium lactate per litre, after which it was wiped off and dried. Strips of this foil were then exposed behind a line negative with the aid of a high-pressure mercury-vapour lamp and a sensitometer, after which they were treated for a few seconds with an aqueous solution containing 0.005 mol of mercurous nitrate and 0.01 mol of nitric acid. Then the strips were washed for a short time in distilled water and developed in a stabilized, physical developer, obtained by dissolving in distilled water:
• Lissapol N is a condensation product of alkylphenols and ethylene oxide, containing a polyethylene chain; Armac 12 D is a mixture of dodecyl and tetradecylamine acetate.
• the minimum outgrowth exposure was determined, i.e., the minimum exposure energy per unit of the light-sensitive layer, having, after this development, an outgrown silver layer with an electric resistance which sufiices the aforesaid criterion.
• the tested exposure region (1 to 2 times the minimum outgrowth exposure) yielded only internal silver images.
• the densities of the images obtained with the maximum exposures were, in this case, however immeasurably high.
• Copper sulphate 5 aq. 200 g./litre
• Concentrated sulphuric acid 50 g./litre
• Phenolsulphonic acid sodium 0.5 g./litre
• Use was made, for example, of a copper-deposition time of 2 min. with a current density of 5 A./dm. Copper layers thus obtained could then be electrophoretically coated superficially, for example, with a layer of alumina, by using a suspension of of Alundum in methanol with a field intensity of 37.5 v./cm. for 6 sec. and 3. current of 70 ma.
• Electrolytic intensification with nickel could take place, for example, by means of an aqueous nickel-coating bath containing, per litre, 240 g. of nickel sulphate, 45 g. of nickel chloride and 30 g. of boric acid. The operational temperature of this bath was 40 C. and the current density amounted to 2 to 4 A./dm.
• compositions of stabilized, physical developers yielded corresponding results.
• Two very suitable compositions are mentioned here, in particular:
• the activity of the said developers can be kept substantially constant for a satisfactory time by refreshing the silver nitrate used for the image formation from time to time in the form of small quantities of a 10% by weight of an aqueous solution of silver nitrate.
• Sensitizing solutions containing other light-sensitive diazo-sulphates for example, p-methoxy-benzene-diazosulphonic acid sodium or dimethoxy-Z.S-benzene-diazosulphonic acid sodium-1 and/ or other anti-regression means, such as resorcinol, yielded corresponding results.
• Example 11 Unilaterally white, woodfree litho-paper was sensitized by impregnation, on one side, in the solution of a light-sensitive compound as described in Example I and by drying it. The exposure, the treatment with the mercurous nitrate solution and the stabilized physical development at a temperature of 20 C. of strips of this material took place in the manner described in the preceding example. In order to determine the minimum mirror exposure, moreover, a few strips were developed for 10 minutes at 20 C. in a non-stabilized physical developer obtained by dissolving, in distilled water, metol, citric acid and silver nitrate with concentrations as indicated in the first developer of Example I. With a developing time of 20 min.
• Such a silver layer which had been manufactured in the pattern of a screen grid, was intensified for 15 min. with a current density of 4 A./dm. electrolytically with copper by means of an acidic copper-deposition bath containing 20% by weight of copper sulphate (SH O) and 6% by weight of sulphuric acid in distilled water.
• SH O copper sulphate
• the copper-coated grid was dipped in a polyvinyl-chlorideacetate lacquer and again dried. Then a polyvinylchloride foil of about 25 was applied to the image side and the assembly was compressed for one minute at C. under a pressure of 10 kgs./cm.
• the insulated, flexible grid thus obtained could be readily bent into the form of a cylinder and be thus used as a screen grid for electric coils.
• Example Ill The support material of Example I was sensitized by impregnating it for two minutes in an aqueous solution containing 2% by weight of anthraquinone-disulphonic acid sodium-2,7, after which it was wiped off and dried. Strips of this light-sensitive material were exposed with the aid of a high-pressure mercury-vapour lamp behind a line negative and then treated, for 15 sec., with an aqueous solution containing 0.01 mol of silver nitrate and 0.2 mol of acetic acid acetate buffer.
• the resistance of the silver layer obtained amounted to about 300 ohms per square.
• the last-mentioned value dropped, after a treatment, for one minute, with a 0.1 N solution of potassium chloride in water to about 2.7 ohms per square.
• Similar resistance-reducing effects could be achieved by replacing the treatment with the potassium chloride solution by one of the solutions of the following compounds: sodium bromide, Sodium iodide, sodium thiosuphate, sodium sulphite, sulphuric acid, potassium hydroxide, potassium thiocyanide and sodium sulphide.
• Example IV The support material of Example I was sensitized by impregnating it for two minutes in an aqueous solution containing 0.4 mol of hydroxy-l-diazo-Z-methyl-G-benzene-sulphonic acid-4, 0.05 mol of mercurous nitrate and 0.1 mol of nitric acid per litre, after which it was wiped off and dried. Strips of this material were exposed with the aid of a high-pressure mercury-vapour lamp and then treated, for a few seconds, with distilled water. Then the strips were developed in the stabilized physical developer of the composition referred to in the preamble of Example I. Eventually the developing bath was refreshed after 60 and 120 min. respectively. Finally the developed strips were washed for about 10 min. in distilled water and dried in air.
• Example V The support material of Example I was sensitized by impregnation for 2 min. in an aqueous solution containing 3% by weight of hydroxy-l-diazo-2-naphthalenesulphonic acid-4, 2% by weight of citric acid and 4% by weight of silver nitrate, after which it was wiped off and dried. Strips of this material were exposed behind a line negative with the aid of a water-cooled high-pressure mercury-vapour lamp and then washed for two minutes in distilled water. Then the strips were developed in a stabilized physical developer of the comparison indicated in the first recipe of Example I. The developing bath was refreshed after 60 and 120 min. respectively. Finally the strips were washed again and dried in air.
• an outgrown silver layer was obtained after 30 min. of development, the electric resistance thereof being 980 ohms per square, which value dropped, after a thermal treatment at 150 C. for one hour, to 0.5 ohm per square and, after a chemical treatment in an aqueous solution containing 0.1% by weight of potassium chloride, to 1.1 ohms per square.
• a developing time of 60 min. by using the same exposure, a silver layer was obtained, of which the electric resistance amounted to 340 ohms per square.
• this value dropped to 0.25 ohm per square.
• the minimum outgrowth exposure (developing time 180 min.) was about 32 times lower than the exposure used above.
• Example VI A superficially saponified cellulose tri-acetate foil was sensitized by impregnating it for two minutes in an aqueous solution of 5% by weight of mercuric chloride, 5% by weight of ferric ammonium oxalate and 2.5% by weight of ammonium oxalate, after which it is wiped off and dried. Strips of this foil were exposed to the light of a high-pressure mercury-vapor lamp and then treated for 10 sec. with a 10% by weight solution of sodium sulphite in water and for 1 min. with distilled water. Then the strips were developed in the stabilized physical developer of Example I. The developing bath was refreshed after 60 and min. respectively. Finally the strips were washed for 10 min. in distilled water and dried in air.
• the electric resistance of the external silver layers obtained could be reduced also in this case to a considerable extent by a thermal or a chemical after-treatment or mechanical polishing.
• Example VII Strips of an optically not-sensitized silver halide film of the firm of Gevaert, known under the trademark of Scientia 14 B 50, were exposed preferably with the aid of a mercury-vapour lamp, behind a line negative.
• the developer had, in the latter case, the following composition: 1.6% by weight of metol, 3.2% by weight of citric acid, 0.4% by weight of silver nitrate, 0.02% by weight of Lissapol N and 0.02% by weight of Armac 12 D in distilled Water.
• a method of producing by photographic means an external electrically conductive noble-metal pattern on an at least superficially non-metallic, electrically nonconductive, at least slightly hydrophilic macro-molecular support comprising the steps of sensitizing said support With at least one light-sensitive compound selected from the group consisting of the silver halides and those organic compounds the light reaction products of which are capable of reacting in the presence of water with a water soluble metallic compound selected from the group consisting of water soluble silver and mercurous compounds to form free silver and mercury metal at the exposed portions, said water soluble metallic compound being present prior to development, selectively exposing said support for a time at least equivalent to an outgrowth exposure, treating said selectively exposed support with said water soluble metallic compound in the presence of moisture, thereby forming an internal latent image containing free metal selected from the group consisting of silver and mercury at the exposed areas and physically developing said latent image by treatment with a developing solution comprising an aqueous solution of a water soluble reducible salt of a noble metal selected from the group consisting of silver
• the resultant noblemetal pattern is a silver layer and is treated with an aqueous solution of at least one compound having a potential determining anion with respect to the silver metal.
• the light-sensitive compound is an aromatic diazo-sulphonate and the lightsensitive layer contains a material which prevents the diazo-sulphonate from being reformed from the light-reaction products so that the sulphite remains capable of reacting with the mercurous compound to form a mercury nucleus.
• the light-sensitive organic compound is an o-hydroxy-naphthalene diazonium compound.

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• 0
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  • NL NL113853D patent/NL113853C/xx active
• 1960
  • 1960-07-11 US US41799A patent/US3223525A/en not_active Expired - Lifetime
  • 1960-07-19 DK DK282260AA patent/DK107988C/da active
  • 1960-07-19 CH CH828460A patent/CH420853A/de unknown
  • 1960-07-19 GB GB25135/60A patent/GB954208A/en not_active Expired
  • 1960-07-19 SE SE7008/60A patent/SE303074B/xx unknown
  • 1960-07-20 DE DE19601446699 patent/DE1446699B2/de not_active Withdrawn
  • 1960-07-20 ES ES0259764A patent/ES259764A1/es not_active Expired

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