IE45648B1 - Improvements in or relating to biologically active gels - Google Patents

Improvements in or relating to biologically active gels

Info

Publication number
IE45648B1
IE45648B1 IE160877A IE160877A IE45648B1 IE 45648 B1 IE45648 B1 IE 45648B1 IE 160877 A IE160877 A IE 160877A IE 160877 A IE160877 A IE 160877A IE 45648 B1 IE45648 B1 IE 45648B1
Authority
IE
Ireland
Prior art keywords
gel
biologically active
inorganic
feed solution
active component
Prior art date
Application number
IE160877A
Other versions
IE45648L (en
Original Assignee
Atomic Energy Authority Uk
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Atomic Energy Authority Uk filed Critical Atomic Energy Authority Uk
Publication of IE45648L publication Critical patent/IE45648L/en
Publication of IE45648B1 publication Critical patent/IE45648B1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2/00—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
    • B01J2/02—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic by dividing the liquid material into drops, e.g. by spraying, and solidifying the drops
    • B01J2/06—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic by dividing the liquid material into drops, e.g. by spraying, and solidifying the drops in a liquid medium
    • B01J2/08—Gelation of a colloidal solution
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
    • A01N25/02—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing liquids as carriers, diluents or solvents
    • A01N25/04—Dispersions, emulsions, suspoemulsions, suspension concentrates or gels
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
    • A01N25/08—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing solids as carriers or diluents
    • A01N25/10—Macromolecular compounds
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/02—Inorganic compounds
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/14—Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
    • A61K9/16—Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
    • A61K9/1605—Excipients; Inactive ingredients
    • A61K9/1611—Inorganic compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/0052—Preparation of gels
    • B01J13/0056—Preparation of gels containing inorganic material and water

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Dispersion Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Zoology (AREA)
  • Epidemiology (AREA)
  • Dentistry (AREA)
  • Wood Science & Technology (AREA)
  • Plant Pathology (AREA)
  • Environmental Sciences (AREA)
  • Pest Control & Pesticides (AREA)
  • Medicinal Chemistry (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Toxicology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Agronomy & Crop Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Medicinal Preparation (AREA)

Abstract

A biologically active gel is obtained by treating, in order to bring about gelatinisation, a starting solution which contains an inorganic species and a biologically active component, which during use is active or becomes active, so that an inorganic gel is produced by a sol-gel conversion and thus a biologically active gel is generated which contains the biologically active component, which during use is active or becomes active, distributed throughout the inorganic gel.

Description

PATENT APPLICATION BY (71) UNITED KINGDOM ATOMIC ENERGY AUTHORITY, A BRITISH AUTHORITY, OF 11 CHARLES II STREET, LONDON S.W.l, ENGLAND.
Price 90p The present invention relates to biologically active gels and the preparation thereof and finds one application in relation to the preparation of pharmaceutical gels.
According to one aspect of the present invention there is provided a 5 process for the preparation of a biologically active gel comprising treating a feed solution containing an inorganic species and a biologically active component to effect gelation by a sol-gel transformation to form an inorganic gel and thereby give a biologically active gel comprising the biologically active component distributed throughout the inorganic gel.
By “biologically active component we mean a component which exhibits biological activity in a chosen environment as exemplified hereinafter and biologically active gel is to be construed as meaning a gel containing a biologically active component as hereinbefore defined. Thus the component may be, for example, a pharmaceutically active component so that the biologically active gel is a pharmaceutically active gel (i.e. a pharmaceutical gel) or the biologically active component may be a pesticide in which case the biologically active gel will have pesticidal activity. Alternatively, for example, a herbicidal gel may be formed by incorporation of a herbicide as the biologically - 2 45648 active component. As a further alternative the biologically active component may be a toxin capable of inhibiting growth, in an aquatic environment (e.g. for inhibiting growth of aquatic weeds and molluscs), and the biologically active gel can be used in marine anti-fouling paints. In yet a further alternative the biologically active component may be an algicide so that the biologically active gel has algicidal activity.
In accordance with a preferred embodiment of the present invention there is provided a process for the preparation of a pharmaceutical gel comprising treating a feed solution containing an inorganic species and a pharmaceutically active component to effect gelation by a sol-gel transformation to form an inorganic gel and thereby give a pharmaceutical gel comprising the pharmaceutically active component distributed throughout the inorganic gel.
It will be appreciated that the inorganic species in the feed solution may be for example in the form of a colloidal dispersion (sol) or an anion deficient salt solution, or a mixture thereof.
The sol-gel transformation may be effected by known methods. For example, concentration of the inorganic species by dewatering.
Conveniently, the inorganic species can be an inorganic compound or a mixture of inorganic compounds (e.g. A^Og, Al^O-j/MgO or AlgOySiO^) and the preparation of the feed solution can conveniently include the step of mixing a solution or sol of the inorganic compound, or compounds, with the biologically acti'ye component or a solution thereof.
He prefer that the inorganic gel is an oxide, hydrous oxide or hydroxide and in one particular preferred embodiment the inorganic gel is an oxide, hydrous oxide or hydroxide of aluminium.
In one embodiment of the process of the invention the inorganic gel is preferably formed by the gelation of a colloidal solution by a “sol-gel process.
The invention is not limited to gels containing only an inorganic gel and an active component since further additives may be introduced. - 3 40648 Thus in another embodiment of the process of the present invention the feed solution may also include a polymeric substance so that the gel product produced by the sol-gel transformation contains an inorganic gel, a polymeric organic substance and a biologically active component (e.g. a pharmaceutically active component).
The polymeric organic substance may be, for example, a substance which can be used as an “organic gelling agent (sometimes called a “gelating agent) in a gel precipitation process. Such organic gelling agents are usually water soluble high molecular weight polymeric organic compounds (e.g. dextran, polyvinyl alcohol, dextrin and starch). Our British Patents Nos. 1,175,834, 1,231,385, 1 ,253,807, 1,313,750 and 1,363,532 relate to gel precipitation processes and reference should be made to these for information regarding such processes.
Reference may also be made to Patent Specification No. 45649which disclose inter alia the use of polymeric organic substances in the preparation of active gels (e.g. pharmaceutical gels).
The gelation by sol-gel transformation to form the inorganic gel may be effected in a number of ways and may in some methods involve some degree of dewatering or drying of the feed solution.
For example, in one embodiment the feed solution (optionally containing a polymeric organic substance as hereinbefore disclosed) may be spray dried to give substantially spherical active gel particles (e.g. particles of pharmaceutically active gel).
In another embodiment the feed solution may be freeze-dried to give a biologically active gel.
In a further embodiment the feed solution may be subjected to organic dewatering wherein feed solution is contacted with an organic liquid capable of extracting water from the feed solution to give a biologically active gel. - 4 -. 43648 In yet a further embodiment the feed solution may be dried by azeotropic distillation.
Reference may be made to our British Patent Specification No. 1,419,492 in connection with organic dewatering and azeotropic distillation.
It will be understood that in using organic dewatering or azeotropic distillation the biologically active component (e.g. pharmaceutical component) should have a low solubility in the organic liquid used for dewatering.
If the feed solution is formed into droplets during the organic dewatering or azeotropic distillation a particulate gel product may be obtained.
Other convenient methods for effecting the gelation to form a gel may be used in the practice of the present invention. For example liquid ion exchange may be used. An example of liquid ion exchange is where ions are removed from a solution or a sol (e.g. nitrate ions may be removed by use of Prirasne (Registered Trade Mark) JMT in an organic solvent therefor).
According to another aspect of the present invention there is provided a biologically active gel comprising a biologically active component distributed throughout an inorganic gel said inorganic gel having been formed by a sol-gel transformation.
Preferably the biologically active component is a pharmaceutically active component so that the biologically active gel is a pharmaceutically active gel.
We prefer that a pharmaceutically active gel is in the form of substantially spherical gel particles which is convenient for ease of handling and administration to patients. This can be achieved by forming the feed solution into droplets prior to the formation of the inorganic gel.
Substantially spherical pharmaceutical gel particles in accordance with the present invention may range in size from several microns to several millimetres. In the case of a pharmaceutical gel small particles (say 1-1000 microns) may be administered orally by capsule whereas larger particles (say - 5 1-5 ram) may be ohally administered individually.
In accordance with a further aspect of,the present invention there is provided a process for the production of a biologically active gel wherein a feed solution containing an inorganic species and a biologically active component is treated to effect gelation to form a biologically active gel comprising a biologically active component distributed throughout an inorganic gel, wherein the structure of the gel is controlled thereby to determine the rate at which the biologically active component will be released from the gel in use.
In a preferred embodiment of the immediately foregoing aspect of the present invention there is provided a process for the production of a pharmaceutical gel wherein a feed solution containing an inorganic species and a pharmaceutically active component are treated to effect gelation thereby to form a pharmaceutical gel comprising a pharmaceutically active component distributed throughout an inorganic gel, wherein the structure of the gel is controlled thereby to determine the rate at which the active component will be released when the gel is administered to a patient.
The structure of the gel and hence the rate at which the biologically active component is released may be determined by modifying the composition of the feed solution thereby to modify the composition of the biologically active gel. Thus, an additional inorganic compound can be included in the feed solution thereby to modify the composition of the gel. (Examples of inorganic compounds suitable for use as additives in connection with the immediately foregoing embodiment are silica and pyrolytic alumina).
The structure of the gel may be controlled, and hence the biologically active component release rate determined (e.g. pharmaceutical release rate), by the choice of method for effecting the gelation to form the inorganic gel.
Also, in certain cases the structure of the gel may be controlled, and release rate determined, by treating the gel after its formation. - 6 45648 The rate at which the biologically active component is released may depend upon a number of factors. These are: (a) pH of medium (e.g. stomach, intestine in the case of a pharmaceutically active gel) (b) size of gel particle (c) chemical composition of the inorganic gel (d) porosity of the gel (e) crystal size and structure of the inorganic gel (f) water content of the gel (g) affinity of the gel for water (hydrophilic nature) (h) the presence or absence of a polymeric organic substance (it is believed that this may be particularly significant if the polymeric organic substance is partially complexed with tha incrganic gel).
The release rate in a given situation is expected to be a complex function of all the above factors.
The release rate may be influenced by the extent of water removal from the feed solution, the temperature reached in effecting the gelation and choice of components in the feed solution (e.g. sol, dispersion or anion deficient salt solution or chemical composition (e.g. Si02 or AlgO^))· In accordance with yet a further aspect the invention provides a biologically active gel provided by the process of the invention.
In accordance with a still further aspect the present invention provides a biologically active gel the structure of which is controlled thereby to determine the rate at which the biologically active component will be released from the gel in use.
In a preferred embodiment of the immediately foregoing aspect of the present invention there is provided a pharmaceutically active gel the structure of which is controlled thereby to determine the rate at which the pharmaceutically active component will be released from the gel when administered to a patient. - 7 45648 It is believed that pharmaceutically active gels in accordance with the present invention have advantages over .conventional tabletting and encapsulation in regard to uniformity of distribution of the pharmaceutically active component throughout the pharmaceutically active gel and the concentration of pharmaceutically active component obtainable in the gel.
The invention also provides a.pharmaceutical composition comprising a pharmaceutically active gel in accordance with the invention in admixture with a pharmaceutically acceptable carrier therefor.
The invention further provides a method of making a pharmaceutical composition comprising mixing a pharmaceutically active gel in accordance with the invention with a pharmaceutically acceptable carrier therefor.
The invention will now be further described by way of example only, as follows: EXAMPLE 100 g dispersible boehmitej prepared in accordance with British Patent Specification No. 1,174,648 was dispersed in 500 ml distilled water containing 1.0 gm inripranrine hydrochloride. The resulting mixture was spray dried to form a predominantly spherical powder with good flowing properties.
In normal saline solution the imipramine hydrochloride was released within five minutes.

Claims (27)

1. A process for the preparation of a biologically active gel comprising treating a feed solution containing an inorganic species and a biologically active component to effect gelation by a sol-gel transformation to form an inorganic gel and thereby give a biologically active gel comprising the biologically active component distributed throughout the inorganic gel,
2. A process for the preparation of an active gel comprising a pharmaceutical gel which process comprises treating a feed solution containing an inorganic species and a pharmaceutically active component to effect gelation by a sol-gel transformation to form an inorganic gel and thereby give a - 8 4 5348 pharmaceutical gel comprising the pharmaceutically active component distributed throughout the inorganic gel.
3. A process as claimed in Claim 1, wherein the biologically active component is a pharmaceutically active component, or a pesticide, or a herbicide, or a toxin capable of inhibiting growth in an aquatic environment, or an algicide.
4. A process as claimed in any one of Claims 1 to 3, wherein the inorganic species in the feed solution is in the form of a colloidal dispersion (sol), or an anion deficient salt solution, or a mixture thereof. 5. A process as claimed in any one of Claims 1 to 4, wherein the inorganic species is an inorganic compound or a mixture of inorganic compounds.
5. A process as claimed in Claim 5, wherein the compound is AlgOg, or the mixture of compounds is AlgOg/MgD or AlgOj/Si0?.
6. 7. A process as claimed in Claim 5 or 6 wherein the feed solution is prepared by a process including the step of mixing a solution or sol of the inorganic compound, or compounds, with the biologically active component or a solution thereof.
7. 8. A process as claimed in any one of Claims 1 to 7, wherein the inorganic gel is an oxide, hydrous oxide or hydroxide.
8. 9. A process as claimed in Claim 8, wherein the inorganic gel is an oxide, hydrous oxide or hydroxide of alumina.
9. 10. A process as claimed in any preceding claim, wherein the feed solution also contains a polymeric organic substance.
10. 11. A process as claimed in any one of the preceding claims wherein the inorganic gel is formed by gelation of a colloidal solution.
11. 12. A process as claimed in any one of the preceding claims, wherein the sol-gel transformation is effected by concentration of the inorganic species by dewatering or drying.
12. 13. A process as claimed in any one of the preceding claims, wherein the feed solution is spray-dried to give substantially spherical active gel particles. - 9
13. 14. A process as claimed in any one of Claims 1 to 12 wherein the feed solution is freeze-dried to give an active gel. ·
14. 15. A process as claimed in any one of Claims 1 to 12, wherein the feed solution is subjected to organic dewatering by contact with an organic liquid capable of extracting water from the feed solution to give a biologically active gel.
15. 16. A process as claimed in any one of Claims 1 to 12, wherein the feed solution is dried by azeotropic distillation.
16. 17. A process as claimed in Claim 15 or Claim 16, wherein the feed solution is formed into droplets during the organic dewatering or azeotropic distillation so that a particulate gel product is obtained.
17. 18. A process for the production of a biologically active gel by a sol-gel transformation as claimed in any preceding' claim, wherein the structure of the gel is controlled, thereby to determine the rate at which the biologically active component will be released from the gel in use, by (a) selecting the method of gelation; or (b) controlling the extent of water removal from the feed solution, or (c) selecting the components in the feed solution thereby to control the chemical composition and/or physical characteristics of the gel, or (d) controlling the temperature reached during gelation, or any combination of (a) to (d).
18. 19. A process as claimed in Claim 18, for the production of a biologically active gel comprising a pharmaceutical gel wherein the structure of the gel is . controlled thereby to determine the rate at which the biologically active component will be released when the gel is administered to a patient.
19. 20. A biologically active gel comprising a biologically active component distributed throughout an inorganic gel, said inorganic gel having been formed by a sol-gel transformation.
20. 21. A biologically active gel as claimed in Claim 22, wherein the biologically active component is a pharmaceutically active component so that the biologically - 10 43648 active gel is a pharmaceutically active gel.
21. 22. A biologically active gel as claimed in Claim 22 or Claim 23 in the form of substantially spherical particles.
22. 23. A biologically active gel produced by a process as claimed in any one 5 of Claims 1 to 19.
23. 24. A pharmaceutical composition comprising a pharmaceutically active gel as claimed in Claim 21 in admixture with a pharmaceutically acceptable carrier therefor.
24. 25. A method of making a pharmaceutical composition comprising mixing a 10 pharmaceutically active gel as claimed in Claim 21, with a pharmaceutically acceptable carrier therefor.
25. 26. A process for the preparation of a biologically active gel substantially as hereinbefore disclosed with reference to the Example.
26.
27. A biologically active gel substantially as hereinbefore disclosed IS with reference to the Example.
IE160877A 1976-08-06 1977-08-02 Improvements in or relating to biologically active gels IE45648B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3297176A GB1590574A (en) 1976-08-06 1976-08-06 Biologically active gels

Publications (2)

Publication Number Publication Date
IE45648L IE45648L (en) 1978-02-06
IE45648B1 true IE45648B1 (en) 1982-10-20

Family

ID=10346741

Family Applications (1)

Application Number Title Priority Date Filing Date
IE160877A IE45648B1 (en) 1976-08-06 1977-08-02 Improvements in or relating to biologically active gels

Country Status (6)

Country Link
JP (1) JPS5320411A (en)
CH (1) CH639869A5 (en)
DE (1) DE2735392A1 (en)
FR (1) FR2360345A1 (en)
GB (1) GB1590574A (en)
IE (1) IE45648B1 (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6227048Y2 (en) * 1979-04-10 1987-07-11
JPS55138311A (en) * 1979-04-17 1980-10-29 Yanmar Agricult Equip Harvester
JPS6334486Y2 (en) * 1979-06-14 1988-09-13
ATE71293T1 (en) * 1986-09-18 1992-01-15 London Pharmacy Innovation DRUG FORMULATION.
IL83715A0 (en) * 1987-08-31 1988-01-31 Yeda Res & Dev Pharmaceutical anti-protozoal compositions
EP0680753A3 (en) * 1994-05-06 1996-08-28 Feinchemie Gmbh Sebnitz Metal oxide composite with controllable release.
GB9504630D0 (en) * 1995-03-08 1995-04-26 Kodak Ltd A material and method for inhibiting bacterial growth in an aqueous medium
FR2732189B1 (en) * 1995-03-27 1997-05-09 Kodak Pathe ORGANIC-INORGANIC GELS FOR DELIVERING CONTROLLED QUANTITIES OF ACTIVE COMPOUNDS IN AQUEOUS SOLUTIONS
GB9615944D0 (en) * 1996-07-30 1996-09-11 Kodak Ltd A material,method and apparatus for inhibiting microbial growth in an aqueous medium
AUPQ573300A0 (en) 2000-02-21 2000-03-16 Australian Nuclear Science & Technology Organisation Controlled release ceramic particles, compositions thereof, processes of preparation and methods of use
DE102006008535A1 (en) * 2006-02-22 2007-08-30 Stiftung Nano Innovations - For A Better Living, Olten Anitbakterielle coating composition based on a silica-producing agent, an application set, a nanoscale coating, the production of the coating, the further processing of the coating and their use
DE102006008534A1 (en) * 2006-02-22 2007-08-30 Stiftung Nano Innovations - For A Better Living, Olten Container closure coating composition, container closure coating, their preparation and use
CA2702340C (en) 2006-10-12 2014-12-16 The University Of Queensland Compositions and methods for modulating immune responses
CN103328499A (en) 2010-11-01 2013-09-25 悉尼科技大学 Immune-modulating agents and uses therefor

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR881457A (en) * 1941-12-24 1943-04-27 Cie De Prod Chim Et Electro Me Improvement in antiparasitic porridge
FR891043A (en) * 1942-06-29 1944-02-24 Instant alumina gel
GB880261A (en) * 1957-03-13 1961-10-18 Albright & Wilson Mfg Ltd Improvements in or relating to the production of aqueous aluminium chlorhydrate gels
FR1366891A (en) * 1963-06-04 1964-07-17 Stull Chemical Simultaneous preparation and application of chemical mixtures for agriculture
AU6650174A (en) * 1973-03-14 1975-09-11 John Thompson Spraying gels
DE2500350A1 (en) * 1975-01-07 1976-07-08 Kali Chemie Ag Aluminium fluoride contg spheroidal particles for catalysis - produced from alumina hydrosoln and aluminium fluoride suspension

Also Published As

Publication number Publication date
GB1590574A (en) 1981-06-03
DE2735392A1 (en) 1978-02-09
FR2360345B1 (en) 1983-10-14
CH639869A5 (en) 1983-12-15
FR2360345A1 (en) 1978-03-03
IE45648L (en) 1978-02-06
JPS5320411A (en) 1978-02-24

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