Method of making flowable alkaline thiosulfate/alkaline sulfite and the product thereof

Abstract

A method for making flowable alkaline thiosulfate, flowable alkaline sulfite, or a combination of the two, by blending an alkaline thiosulfate, an alkaline sulfite, or a combination of the two, with an alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.in an amount effective to render the alkaline thiosulfate, the alkaline sulfite, or the combination freely flowable, and the product of this method. It has been found that the product of this method, such as freely flowable ammonium thiosulfate powder mixture, can be stored in a freely flowable condition for extended periods of time and can be dissolved into solution readily to form a clear non-turbid solution. The freely flowable ammonium thiosulfate powdered mixture of the present invention is particularly useful as a photographic fixative and bleach fixative for processing photographic elements.

What is claimed is: 
     
       1. A flowable powdered mixture comprising (a) a member selected from the group consisting of a hygroscopic alkaline thiosulfate, a hygroscopic alkaline sulfite, and a mixture thereof, and (b) a dry alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.in an amount from about 0.05 to 10%, by weight, of said mixture which is effective to provide flowability to the mixture. 
     
     
       2. A flowable powdered mixture as claimed in claim 1, comprising a hygroscopic alkaline sulfite and a dry alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde.Iaddend.. 
     
     
       3. A flowable powdered mixture as claimed in claim 2, wherein said alkaline sulfite is selected from the group consisting of hygroscopic ammonium sulfite and hygroscopic potassium sulfite. 
     
     
       4. A flowable powdered mixture as in claim 2, further comprising an alkali metal bisulfite. 
     
     
       5. A flowable powdered mixture as claimed in claim 2, further comprising a hygroscopic alkaline thiosulfate. 
     
     
       6. A flowable powdered mixture as claimed in claim 5, wherein said alkaline thiosulfate comprises ammonium thiosulfate, said alkaline sulfite comprises ammonium sulfite monohydrate and said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.comprises potassium . .naphthalene sulfonate.formaldehyde.!. .Iadd.naphthalenesulfonate•formaldehyde.Iaddend.. 
     
     
       7. A flowable powdered mixture as claimed in claim 1, wherein said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.is potassium naphthalene sulfonate-formaldehyde. 
     
     
       8. A flowable powdered mixture as claimed in claim 1, further comprising a powdered photographic bleaching agent. 
     
     
       9. A flowable powdered mixture as claimed in claim 8, wherein said photographic bleaching agent comprises a ferric complex of an aminopolycarboxylic acid. 
     
     
       10. A flowable powdered mixture comprising an hygroscopic alkaline thiosulfate and a dry alkali metal . .arylsulfonate.formadehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.in an amount from about 0.05 to 10%, by weight, of said mixture to provide flowability to the alkaline thiosulfate. 
     
     
       11. A method of making a flowable alkaline thiosulfate powdered mixture comprising mixing (a) a hygroscopic alkaline thiosulfate with (b) a dry alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.in an amount from about 0.05 to 10%, by weight, of said mixture which is effective to provide flowability to the mixture. 
     
     
       12. A method as claimed in claim 11, wherein said hygroscopic alkaline thiosulfate is selected from the group consisting of ammonium thiosulfate and potassium thiosulfate. 
     
     
       13. A method as claimed in claim 11, further comprising mixing an alkaline sulfite with said hygroscopic alkaline thiosulfate and said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde.Iaddend.. 
     
     
       14. A method as claimed in claim 13, wherein said mixing further comprises the following steps: (1) blending said alkaline sulfate with 0.5 to 5% by weight of said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde.Iaddend.;   (2) if the moisture content of the resulting mixture is above about 2.0 wt %, then drying the resulting mixture (a) at 80° C. for 1.5 to 2 hours, (b) at room temperature for approximately 12 hours, or (c) at 50° C. for 1.5 to 2 hours under a vacuum of 30 inches Hg, or (d) at a temperature and for a time and at a pressure condition substantially equivalent to (a) or (b) or (c);   (3) grinding the mixture to a substantially powder form to form a preblended mixture; and   (4) blending the thus-formed preblended mixture with an alkaline thiosulfate in an amount effective to render said alkaline thiosulfate freely flowable.   
     
     
       15. A method as claimed in claim 13, wherein said alkaline thiosulfate comprises ammonium thiosulfate, said alkaline sulfate comprises ammonium sulfite monohydrate and said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.comprise potassium . .naphthalene sulfonate.formaldehyde.!. .Iadd.naphthalenesulfonate•formaldehyde.Iaddend.. 
     
     
       16. A method as claimed in claim 15, wherein said alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.comprises potassium . .naphthalenesulfonate.formaldehyde.!. .Iadd.naphthalenesulfonate•formaldehyde.Iaddend.. 
     
     
       17. A method as claimed in claim 16, wherein said alkaline thiosulfate comprises ammonium thiosulfate and is present in an amount of from about 40 to 80% by weight; said alkaline sulfite comprises ammonium sulfite monohydrate and is present in an amount of from about 20 to 60% by weight, and said potassium . .naphthalenesulfonate.formaldehyde.!. .Iadd.naphthalenesulfonate•formaldehyde .Iaddend.is present in amount of from about 0.1 to 10% by weight, all individual weights being based on the final mixture weight. 
     
     
       18. A method as claimed in claim 14, wherein said method comprises grinding said mixture of alkaline sulfite and alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.obtained in step (3) to a particle size of between 100 and 200 μm. 
     
     
       19. A method as claimed in claim 13, wherein said alkaline sulfite comprises ammonium sulfite monohydrate, and wherein said method comprises admixing said ammonium sulfite monohydrate within alkali metal metabisulfite in an amount effective to stabilize said ammonium sulfate monohydrate. 
     
     
       20. The product of the method of claim 11. 
     
     
       21. The product of the method of claim 17. 
     
     
       22. The product of the method of claim 19. 
     
     
       23. A method of mating an improved fixing solution comprising the steps of (1) mixing a hygroscopic alkaline thiosulfate, a hygroscopic alkaline sulfite and a dry alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.in an amount from about 0.05 to 10%, by weight, of said mixture which is effective to provide flowability to the blended mixture, and (2) dissolving the thus-formed blended mixture into an aqueous solution. 
     
     
       24. A method as claimed in claim 23, wherein said mixing further comprises the following steps: (1) forming an initial mixture by blending alkaline sulfite with 0.1 to 10% of an alkali metal . .arylsulfonate.formaldehyde.!. .Iadd.arylsulfonate•formaldehyde .Iaddend.based on initial mixture weight;   (2) if the moisture content of the initial mixture is above about 2.0 wt, then drying the resulting mixture at 80° C. for 1.5 to 2 hours or at room temperature for approximately 12 hours, or (c) at 50° C. for 1.5 to 2 hours under a vacuum of 30 inches of Hg, or (d) at a temperature and for a time and a pressure condition substantially equivalent to (a) or (b) or (c);   (3) grinding the initial mixture to at least a substantially granular or powder form;   (4) blending the thus-formed dry and ground preblended initial mixture with an alkaline thiosulfate; and   (5) dissolving the thus-formed blended mixture into an aqueous solution.   
     
     
       25. The product of the method of claim 23.