Classifications

• • 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
  • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
  • G03C5/264—Supplying of photographic processing chemicals; Preparation or packaging thereof
  • G03C5/266—Supplying of photographic processing chemicals; Preparation or packaging thereof of solutions or concentrates
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B3/00—Line transmission systems
  • H04B3/02—Details
  • H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04M—TELEPHONIC COMMUNICATION
  • H04M1/00—Substation equipment, e.g. for use by subscribers
  • H04M1/738—Interface circuits for coupling substations to external telephone lines
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04M—TELEPHONIC COMMUNICATION
  • H04M1/00—Substation equipment, e.g. for use by subscribers
  • H04M1/738—Interface circuits for coupling substations to external telephone lines
  • H04M1/74—Interface circuits for coupling substations to external telephone lines with means for reducing interference; with means for reducing effects due to line faults

Definitions

• the developers include a solution of a 3-pyrazolidone in a selected non-aqueous or substantially non-aqueous organic solvent.
• the developer may include one or more ingredients additional to the 3-pyrazolidone.
• the pyrazolidone ring is as follows, viz., 1 phenyl 3 pyrazolidone:
• the well-known developing baths are aqueous. These aqueous developing baths, in addition to one or more reducing agents, usually contain an alkali, a preservative such as sodium sulfite, and a restrainer such as potassium bromide or benzotriazole.
• aqueous developing baths in addition to one or more reducing agents, usually contain an alkali, a preservative such as sodium sulfite, and a restrainer such as potassium bromide or benzotriazole.
• developers containing the 3-pyrazolidones have been sold as concentrated aqueous solutions, which have been diluted with additional water just prior to using the complete developing bath; and as well, developers incorporating 3-pyrazolidones have also been sold in powder form which, for use, have been dissolved in water.
• B-pyrazolidones and particularly, 1-phenyl-3-pyrazolidone
• I can be stored stably in dissolved form for indefinite periods and at temperatures up to C., by using selected non-aqueous or substantially non-aqueous organic solvents which fulfill the necessary requirements for compatibility with complete photographic developer compositions.
• I can thus commercially market a non-aqueous or substantially nonaqueous concentrate of the 3-pyrazolidone in a container, packed together with a receptacle which contains an aqueous bath of the other ingredients of the desired developer composition or contains said other ingredients in dry form.
• I thus prevent hydrolytic degradation of the 3-pyra'zolidone, and I mix the contents of said container and receptacle, together with any necessary dilution with water, substantially at the beginning of use. I thus provide a developer having full speed, contrast and capacity.
• I can optionally dissolve in said non-aqueous or substantially non-aqueous organic solvent, one or more of the ingredients in the end mix, this in addition to the 3-pyrazolidone.
• the selected organic solvent in addition to being nonaqueous or substantially non-aqueous, must have high solubility in water at 20 C.30 C. under ordinary atmospheric pressure of 760 millimeters of mercury, or be easily and completely miscible with water under these conditions.
• the selected organic solvent must be compatible or non-reactive with any of the other developer ingredients, and must be non-reactive with the sensitized photographic film or layer and its paper carrier or other carrier, and it must be capable of dissolving a sufiicient ratio of the 3-pyrazolidone compound at 20 C.-30 C. under said ordinary atmospheric pressure, and it must not be unduly toxic or otherwise hazardous to use.
• the selected non-aqueous or substantially non-aqueous organic solvent should dissolve at least five grams of 1-phenyl-3-pyrazolidone per one hundred milliliters of said organic solvent, at 20 C.-30 C. under said ordinary atmospheric pressure and should be capable of dissolving corresponding ratios of other 3-pyrazolidones.
• the chemicals used herein are of the commercial or technical grade.
• Part A This consists of Part A and Part B, which are packed separately and mixed at the time of use, together with added water.
• the benzotriazole is also designated as 1',2,3-benzotriazole. Its formula is C H NHN and it is well known as a photographic restrainer. It is described in page 143 of the 1956 edition of The Condensed Chemical Dictionary, published by Reinhold Publishing Corporation and Chapman & Hall Ltd.
• the ethylene glycol monoethyl ether is well known as Cellosolve. Its formula is CH OHCH OC H It is described in page 240 of said The Condensed Chemical Dictionary.
• Part A is diluted with three parts (by volume) of water if the final mixture is to be used on a photographic emulsion with a film carrier or with 7 parts of Water if the carrier is paper.
• Part B is added to the diluted Par-t A, before or after Part A has been diluted.
• Part A is diluted as stated in Example No. 1, and mixed with Part B.
• Part B Methanol milliliters 20 l-phenyl-3-pyrazolidone grams 1.0
• Part A is diluted as in Example 1 and mixed with Part B.
• Part A is diluted with two parts of water by volume and Part B is added to Part A before or after said dilution.
• Part A is the same as in Example No. 6.
• Part A is diluted as in Example No. 6; Part B is then added.
• the dry powdered mixture of Part A is dissolved in one liter of water at 20 C.30 C. under normal atmospheric pressure, and the aqueous solution is mixed with Part B. No further dilution with Water is required to develop films or prints.
• Part A is the same and is used in the same manner as in Example No. 8.
• the diethylene glycol monomethyl ether also known as methyl Carbitol solvent, has the formula CH OHCH OCH CH OCH It is described in page 220 of said The Condensed Chemical Dictionary.
• Part B is used in combination with Part A, as described in Example No. 8.
• Solvent pH value Methyl Cellosolve, ethylene glycol monomethyl ether 6 .25 Tetrahydrofurfuryl alcohol 4.1 Cellosolve, ethylene glycol monoethyl ether 4.1
• the solution of the 3-pyrazolidone in the selected organic solvent may be packed and shipped in a completely filled and hermetically sealed glass receptacle, which is kept sealed until admixture with the aqueous component of the complete developing bath.
• the selected organic solvents mentioned herein are selective for the desired purpose, because they can dissolve a sufficiently large ratio by weight of the 3-pyrazolidone and they are freely miscible with water at 20 C.30 C.
• the hydroquinone which is mentioned in the examples represents a class of auxiliary organic developing agents, of which many are well known and can be substituted for the hydroquinone.
• the method of providing an aqueous photographic developing bath including a S-pyrazolidone reducing agent which comprises storing the 3-pyrazolidone reducing agent in a solution, said solution being substantially stable against hydrolysis, the solvent of said solution be ing organic and substantially non-aqueous, said solution being freely miscible with Water at 20 C.-30 C. the solubility of said 3-pyrazolidone in said organic solvent at 20 C.-30 C. being an amount corresponding to at least five grams of 1-phenyl-3-pyrazolidone per one hundred milliliters of said solvent, said solution being sufficiently free from water to be substantially stable against hydrolysis during a storage period of at least a year at a storage temperature of 20 C. to at least 55 C., and incorporating said solution into an aqueous medium for providing a developing bath, whereby a bath containing 3-pyrazolidone reducing agent having substantially full speed, contrast, and capacity is provided.
• the organic solvent is selected from a class which consists of ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, tetrahydrofurfuryl alcohol, 1,4-dioxane, Z-chloro-l-ethanol, methanol, dimethyl formamide, and methyl snlfoxide.
• de veloping agent is l-phenyl-3-pyrazolidone.
• said aqueous medium contains an alkali.
• a method of making an aqueous photographic developing bath which consists in mixing a solution of a 3-pyrazolidone reducing agent in a substantially anhydrous organic solvent with an aqueous solution containing auxiliary developing bath agent, the solubility of said pyrazolidone in said organic solvent at 20 C.-30 C. being an amount corresponding to at least five grams of l-phenyl-3-pyrazolidone per one hundred milliliters of said organic solvent.
• a solution of a 3-pyrazolidone developing agent said solution being substantially stable against hydrolysis, the solvent of said solution being organic and substantially non-aqueous, said solution being freely miscible with water at 20 C.-30 C., the solubility of said 3- pyrazolidone in said organic solvent at 20 C.30 C. being an amount corresponding to at least five grams of 1-phenyl-3-pyrazolidone per one hundred milliliters of said solvent, said solution being sufficiently free from water to be substantially stable against hydrolysis during a storage period of at least a year at a storage temperature of 20 C. to at least 55 C. said solution further having hydroquinone dissolved therein.

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• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Computer Networks & Wireless Communication (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)

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Cited By (4)

Citations (2)

• 1960
  • 1960-02-18 US US9418A patent/US3038801A/en not_active Expired - Lifetime
• 1962
  • 1962-01-09 BE BE612439D patent/BE612439A/fr unknown

Patent Citations (2)

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