Abstract: Water-based coal tar emulsions are described which are prepared from a blend comprising coal tar, water, acrylonitrile-butadiene copolymer powders and clay. After the emulsion is prepared from the blend, a rubber latex may be added to the emulsion. Films obtained from the emulsions exhibit desirable elongation and tensile properties.

Abstract: A method of recoating a bitumen-based built-up roofing membrane. The roofing membrane is recoated by removing loose mineral aggregate, if any, from the surface of the existing roofing membrane, cleaning the surface of the existing roofing membrane, applying a bitumen based flood coat over the cleaned surface, and embedding a layer of mineral aggregate material into the flood coat. The flood coat comprising a coal tar composition prepared from a blend comprising from about 80 parts to about 98 parts by weight of coal tar having an overall float test of from about 50 seconds to about 220 seconds, from about 2 parts to about 20 parts by weight of coal tar pitch having a softening point of from about 140 to about 160° C., and from about 1% to about 20% by weight, based on 25 the total weight of the composition, of an acrylonitrile-butadiene copolymer.

Abstract: In one embodiment, this invention relates to a bitumen-based built-up roofing system comprising a structural deck covered with a membrane comprising;(A) at least two plied layers of reinforcement, the bottom layer being attached to said structural deck,(B) a separately applied bitumen-based waterproofing adhesive between each layer wherein each ply is firmly adhered to the bitumen-based adhesive applied between the plies,(C) a bitumen based flood coat over the plied layers, and(D) a protective layer of inert mineral aggregate material embedded in the flood coat, wherein the bitumen in at least the flood coat comprises a coal tar composition prepared from a blend comprising:(1) from about 80 parts to about 98 parts by weight of coal tar having an overall float test of from about 50 seconds to about 220 seconds,(2) from about 2 parts to about 20 parts by weight of coal tar pitch having a softening point of from about 140 to about 160.degree. C.

Abstract: In one embodiment, this invention relates to a bitumen-based built-up roofing system comprising a structural deck covered with a membrane comprising:(A) at least two layers of reinforcement, the bottom layer being attached to said structural deck,(B) a bitumen-based waterproofing adhesive between each layer wherein each layer is adhered to the bitumen-based adhesive between the layers,(C) a bitumen based flood coat over the layers, and(D) a protective layer of mineral aggregate material embedded in the flood coat, wherein the bitumen in at least the flood coat comprises a coal tar composition prepared from a blend comprising:(1) from about 80 parts to about 98 parts by weight of coal tar having an overall float test of from about 50 seconds to about 220 seconds,(2) from about 2 parts to about 20 parts by weight of coal tar pitch having a softening point of from about 140 to about 160.degree. C.

Abstract: Improved coal tar compositions are described which are prepared from a blend comprising:(A) based on the combined weight of coal tar and coal tar pitch, from about 80 parts to about 98 parts by weight of coal tar having an overall float test of from about 50 seconds to about 220 seconds,(B) based on the combined weight of coal tar and coal tar pitch, from about 2 parts to about 20 parts by weight of coal tar pitch having a softening point of from about 140.degree. C. to about 160.degree. C., and(C) from about 1% to about 20% by weight, based on the total weight of the composition, of an acrylonitrile-butadiene copolymer. In one embodiment up to 35 parts by weight of the coal tar (A) is replaced with a coal tar selected from coal tars having softening points of from about 52.degree. C.-60.degree. C., and from about 56.degree. C.-64.degree. C. The coal tar compositions are not emulsions, and generally will not contain any significant amount of water (e.g., less than 0.5% by weight).