Patent GB-191793-A (GB)
Title: An improved process of making arsenical solutions, and suspensions for insecticidal, fungicidal, preservative & like purposes
IPC: B27K3/52
Filed: 1921-10-11
Abstract: In a process for obtaining compositions for insecticidal, fungicidal, and preservative purposes, and for spraying plants, arsenic compounds are treated with halogens or with inorganic or organic halogen-yielding compounds in order to render them soluble in organic solvents.  The solutions thus obtained may be mixed with water and slaked lime added to obtain suspensions of arsenic.  The arsenic compounds specified are arsenic acids, sulphides of arsenic, and Paris green.  Bromine is specified as a suitable halogen and arsenic tribromide, arsenic trichloride, phthalyl chloride, tribromacetic acid, and tetrachlor-naphthalene as suitable halogen-yielding substances.  Solvents specified are acetone, ethers, alcohol, amyl acetate, acetic ester, benzine, benzol, toluol, tar oils, and petroleum.  In one example arsenic trisulphide and arsenic tribromide are fused together and after continued heating acetic ester is added as a solvent and the solution diluted with water and slaked lime to obtain a suspension of arsenic sulphide and calcium arsenite; in another example bromine is added to a pasty mixture of arsenic trisulphide and paraffin-oil and the whole cautiously heated, after which a further quantity of paraffin-oil or other solvent, such as toluol, is added.ALSO:Compositions for treating wood for insecticidal fungicidal and preservative purposes and for spraying plants are prepared by treating arsenic compounds which are not normally soluble in organic solvents with halogens or with inorganic or organic halogen-yielding compounds in order to render them soluble in organic solvents.  The arsenic compounds specified are arsenic acids, sulphides of arsenic, and Paris green.  Bromine is specified as a suitable halogen and arsenic tribromide, arsenic trichloride, phthalyl chloride, tribrom-acetic acid and tetrachlor-naphthaline as suitable halogen-yielding substances. Solvents specified are acetone, ethers, alcohol, amyl acetate, acetic ester, benzine, benzol, toluol, tar oils, and petroleum. For spraying plants the solutions may be diluted with water, and slaked lime added to neutralize any free acid.  In one example, arsenic trisulphide and arsenic tribromide are fused together and after continued heating acetic ester is added as a solvent; in another example, bromine is added to a pasty mixture of arsenic trisulphide and paraffin oil and the whole continuously heated, after which a further quantity of paraffin oil or other solvent, such as toluol, is added.  The treatment of organic solvents with arsenic trichloride, or with mixtures of arsenic oxide and halogens or inorganic halogen compounds, such as thionyl chloride, is excluded from the scope of the invention.  Paints and varnishes containing arsenic chemically bound by condensation products of phenols and formaldehyde are also referred to.ALSO:Compositions for treating wood for insecticidal fungicidal and preservative purposes and for spraying plants are prepared by treating arsenic compounds which are not normally soluble in organic solvents with halogens or with inorganic or organic halogen-yielding compounds in order to render them soluble in organic solvents.  The arsenic compounds specified are arsenic acids, sulphides of arsenic, and Paris green. Bromine is specified as a suitable halogen and arsenic tribromide, arsenic trichloride, phthalyl chloride, tribrom-acetic acid, and tetrachlor-naphthalene as suitable halogen-yielding substances. Solvents specified as acetone, ethers, alcohol, amyl acetate, acetic ester, benzine, benzol, toluol, tar oils, and petroleum. For spraying plants the solutions may be diluted with water, and slaked lime added to neutralize any free acid.  In one example, arsenic trisulphide and arsenic tribromide are fused together, and after continued heating acetic ester is added as a solvent; in another example bromine is added to a pasty mixture of arsenic trisulphide and paraffin oil, and the whole continuously heated, after which a further quantity of paraffin oil or other solvent, such as toluol, is added.  The treatment of organic solvents with arsenic trichloride, or with mixtures of arsenic oxide and halogens or inorganic halogen compounds, such as thionyl chloride, is excluded from the scope of the invention.