Patent GB-926409-A (GB)
Title: Treating materials for dispersion
IPC: C09K23/00
Filed: 1959-04-28
Abstract: Difficultly dispersible materials are converted into readily dispersible form, by subjecting the difficulty dispersible material in granular form to pulsating vibration while on an inclined plane, <PICT:0926409/III/1> exposing the vibrating material to the action of an agent causing partial swelling of the material, and at least partially removing said absorbed agent if desired from the resulting treated material, said inclined plane being at an angle to the horizontal such that material treated by said agent and material untreated by said agent tend to separate.  The partial swelling agent may be provided by a finely divided spray of water in an amount sufficient to cause partial hydration of the material to be treated, and the resulting treated material may be dried to remove absorbed water.  Products so made are readily water-dispersible, non-crumbling, free-flowing and granular.  The particles thereof may have a sponge like structure and be resiliently compressible under manual pressure, between 8 and 60 mesh, mutually repellent, not agglomerating or balling up on contact with water, and having an apparent bulk density at least 40% lower than that of difficulty dispersible commercially available material, and rapidly completely dispersed in water.  Specified materials include water-soluble cellulose ethers, especially carboxymethyl cellulose, methyl cellulose, ethyl celluloses of a degree of ethylation between about 0,5-1,3, hydroxyethyl cellulose and methoxyethyl cellulose, vegetable gums, especially tragacanth, locust bean extract, gum arabic, guar gum, psyllium seed husks, oat gum, mesquite gum, Indian or Chatti gum, Karaya gum, farinaceous materials and other foodstuffs, e.g. flour, cocoa, malted milk, milk powder, and egg powder, water-soluble or water-dispersible plastic materials e.g. polyvinyl pyrrolidone, inorganic materials e.g. lime, fertilizers and pigments, carbohydrate-containing materials, e.g. pectins, starch, dextrins, dextrans, sodium alginate and agar, dyes, and miscellaneous materials, e.g. boric and benzoic acids.  Examples describe the treatment with water of wetting agents, deodorizing agents, perfumes, masking agents and dyestuffs may be added to the water as required. In place of water, other solvents may be used, e.g. alcohol, acetone, acetic acid esters, together with, if desired, chemical agents not soluble in water but soluble in such organic solvents.  Thus, sodium carboxymethyl cellulose and benzoic acid may both be treated with alcohol, and cellulose acetate may be treated with aqueous acetone. Apparatus comprises a downwardly inclined vibratory surface adapted to receive and discharge the material and means for spraying controlled amounts of liquid, e.g. water at an intermediate area of the surface.  Vibration may be produced electromagnetically, the plane of vibration of the electromagnet being preferably inclined, or pneumatically or by the use of spring- or eccentric-actuated vibrators.  The vibratory surface may form a trough, and be inclined at 10-60 degrees to the horizontal, preferably 15-30 degrees, the lower portion of the surface being heated.  The amount of water used may be up to 10% by weight of the material to be treated.  Apparatus as shown comprises a trough 1 fed from hopper 10, material passing along the floor 5 being vibrated by the pulsating electromagnet 8 while water or other liquid is sprayed from spray 11.  Treated material leaves the trough via slot 4 and is collected at 14.ALSO:<PICT:0926409/IV(a)/1> Difficulty dispersible materials are converted into readily dispersible form, by subjecting the difficulty dispersible material in granular form to pulsating vibration while on an inclined plane, exposing the vibrating material to the action of an agent causing partial swelling of the material, and at least partially removing said absorbed agent if desired from the resulting treated material, said inclined plane being at an angle to the horizontal such that material treated by said agent and material untreated by said agent tend to separate.  The partial swelling agent may be provided by a finely divided spray of water in an amount sufficient to cause partial hydration of the material to be treated, and the resulting treated material may be dried to remove absorbed water.  Products so made are readily water-dispersible, non-crumbling, free-flowing and granular.  The particles thereof may have a sponge like structure and be resiliently compressible under manual pressure, between 8 and 60 mesh, mutually repellent, not agglomerating or balling up on contact with water, and having an apparent bulk density at least 40% lower than that of difficulty dispersible, commercially available material, and rapidly completely dispersed in water. Specified materials include water-soluble cellulose ethers, especially carboxymethyl cellulose, methyl cellulose, ethyl celluloses of a degree of ethylation between about 0,5-1,3, hydroxyethyl cellulose and methoxyethyl cellulose, vegetable gums, especially tragacanth, locust bean extract, gum arabic, guar gum, psyllium seed husks, oat gum, mesquite gum, Indian or Ghatti gum, Karaya gum, farinaceous materials and other foodstuff, e.g. flour, cocoa, malted milk, milk powder, and egg powder, water-soluble or water-dispersible plastic materials, e.g. polyvinyl pyrrolidone, inorganic materials, e.g. lime, fertilisers and pigments, carbohydrate-containing materials, e.g. pectins, starch, dextrins, dextrans, sodium alginate and agar, dyes, and miscellaneous materials, e.g. boric and benzoic acids.  Examples describe the treatment with water of (1) and (2) sodium carboxy methyl cellulose, (3) pulverized Irish moss extract, (4) boric acid, (5) polyacrylamide, (6) Karaya gum, (7) whole wheat flour, (8) the acid azo dyestuff Fast Red S., (8) pulverized pectin.  Wetting agents, deodorizing agents, perfumes, masking agents and dyestuffs may be added to the water as required.  In place of water, other solvents may be used, e.g. alcohol, acetone, acetic acid esters, together with, if desired, chemical agents not soluble in water but soluble in such organic solvents.  Thus, sodium carboxymethyl cellulose and benzoic acid may both be treated with alcohol, and cellulose acetate may be treated with aqueous acetone.  Apparatus comprises a downwardly inclined vibratory surface adapted to receive and discharge the material and means for spraying controlled amounts of liquid, e.g. water at an intermediate area of the surface.  Vibration may be produced electromagnetically, the plane of vibration of the electromagnet being preferably inclined, or pneumatically or by the use of spring- or eccentric-actuated vibrators.  The vibratory surface may form a trough, and be inclined at 10-60 degrees to the horizontal, preferably 15-30 degrees, the lower portion of the surface being heated.  The amount of water used may be up to 10% by weight of the material to be treated.  Apparatus as shown comprises a trough 1 fed from hopper 10, material passing along the floor 5 being vibrated by the pulsating electromagnet 8 while water or other liquid is sprayed from spray 11.  Treated material leaves the trough via slot 4 and is collected at 14.ALSO:<PICT:0926409/IV(a)/1> Difficultly dispersible materials are converted into readily dispersible form, by subjecting the difficulty dispersible material in granular form to pulsating vibration while on an inclined plane, exposing the vibrating material to the action of an agent causing partial swelling of the material, and at least partially removing said absorbed agent if desired from the resulting treated material, said inclined plane being at an angle to the horizontal such that material treated by said agent and material untreated by said agent tend to separate. The partial swelling agent may be provided by a finely divided spray of water in an amount sufficient to cause partial hydration of the material to be treated, and the resulting treated material may be dried to remove absorbed water.  Products so made are readily water-dispersible, non-crumbling, free-flowing and granular. The particles thereof may have a sponge-like structure and be resiliently compressible under manual pressure, between 8 and 60 mesh, mutually repellent, not agglomerating or balling up on contact with water, and having an apparent bulk density at least 40% lower than that of difficultly dispersible, commercially available material, and rapidly completely dispersed in water. Specified materials include benzoic acid.  Wetting agents, p  deodorising agents, perfumes, masking agents and dyestuffs may be added to the water as required.  In place of water, other solvents may be used, e.g. alcohol, acetone, acetic acid esters, together with, if desired, chemical agents not soluble in water but soluble in such organic solvents.  Thus, benzoic acid may be treated with alcohol.  Apparatus comprises a downwardly inclined vibratory surface adapted to receive and discharge the material and means for spraying controlled amounts of liquid, e.g. water at an intermediate area of the surface.  Vibration may be produced electromagnetically, the plane of vibration of the electromagnet being preferably inclined, or pneumatically or by the use of spring- or eccentric-actuated vibrators.  The vibratory surface may form a trough, and be inclined at 10-60 degrees to the horizontal, preferably 15-30 degrees, the lower portion of the surface being heated.  The amount of water used may be up to 10% by weight of the material to be treated.  Apparatus as shown comprises a trough I fed from hopper 10, material passing along the floor 5 being vibrated by the pulsating electromagnet 8 while water or other liquid is sprayed from spray 11.  Treated material leaves the trough via slot 4 and is collected at 14.ALSO:<PICT:0926409/IV(a)/1> Difficulty dispersible materials are concerted into readily dispe