Compositions of an aqueous emulsion of a bitumen and a drilling
mud bentonite are especially adapted for cold application and provide
What is claimed is:
1. A colloidal aqueous emulsion of a bitumen and a drilling mud
bentonite composition especially adapted for cold application, wherein
the drilling mud bentonite conforms to API specification 13A.
2. The emulsion of claim 1 in which the bentonite yields about
180 to 240 barrels per ton.
3. The emulsion of claim 2 in which the bitumen is at least one
of asphalt or coal tar.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The use of bitumens (i.e., asphalt and cold tar) for roofing and
other applications is well known. The advantage of cold applicability,
e.g. on flat roofs so as to avoid working with a hot material at
a job site is also well known. It is desirable to achieve improved
formulations to increase the economy of the effort and improve the
properties of the treated materials.
2. Description of the Background Art
U.S. Pat. No. 5,840,105 discloses the use of bentonite from drilling
muds for sodium silicate and fine mica coatings. U.S. Pat. No. 5,970,893
discloses clay liners as barriers for the containment of pollutants
or toxic waste.
SUMMARY OF THE INVENTION
It has now been found that aqueous emulsions of specific drilling
mud bentonite with bitumen provide formulations that have markedly
decreased costs and markedly improved properties for cold application.
It is surprising to find that this specialty bentonite provides
such superior results outside the petroleum drilling mud field.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The drilling bentonite mud conform to American Petroleum Institute
(API) specification 13A which yield approximately 120 to 280 barrels
of 15 centiposes mud per ton, preferably about 180 to 240 barrels
per ton. Typical bentonites with their trademarks Hydraul-EZ; KWIK-THIK
Asphalt is a bitumen derived from a number of materials such as,
for example, petroleum, shale oil, gilsonite and the like. Asphalt
is a thick, viscous mixture of compounds such as, for example, paraffinic,
cycloaliphatic and aromatic hydrocarbon and lesser amounts of heterocylic
compound containing sulfur, nitrogen or oxygen. Although asphalt
can be obtained from natural sources, it is primarily derived as
the residue of petroleum distillation (e.g., the bottom product
of a vacuum distillation of a topped crude). Although this invention
is not limited thereto, it is preferred that the asphalt have a
penetration (ASTM D5) at 77 degrees F. dmm: ranging from about 5
to about 300 dmm and more preferably from about 50 to about 200
dmm and conform in general to specification outlined by ASTM D312,
D946 and/or D449.
The asphalt can be utilized in the form of an aqueous emulsion
readily available in the trade, see ASTM D1227, and thus has a water
content of about 40-60 wt.%.
Coal tar is a bitumen derived from crude coal tar, water gas tar,
oil gas tar or from combination of such tars with their constituents.
Coal tar is a black, viscous, naphthalene-like odor, amorphous residue
mainly from distillation of coal. The majority of its composition
is polynuclear aromatic compounds such a aromatic hydrocarbon, naphthalenic,
phenolic, anthracenic, quinolinic compound with trace of insoluble
materials. Different grades have different float tests and softening
points. Although this invention is not constrained to, the preferred
coal tars have a float test at 122 degrees F., seconds: ranging
from about 75 to bout 230 seconds and more preferably from about
180 to 220 seconds and conform in general to specification outlined
by RT-10 (Road tar-10) RT-11 and RT-12 in ASTM D490.
The coal tar can be utilized in the form of an aqueous emulsion
readily available in the trade (see Federal Specification RP 355e)
and thus has a maximum water content of about 53 wt. %.
At least one of asphalt and coal tar are employed, depending on
desired final product.
Subject to the foregoing, the ranges of components are about:
wt. % of Emulsion Bitumen 5-50 Asphalt and/or Coal tar 5-50 Drilling
Mud Bentonite 3-8 Water 15-55 Specialty Additives 0.1-2
The specialty additives include e.g. mineral salt to increase emulsability;
complex organic acids such as acetic acid etc. to bring the pH to
a range of 4-6, also to enhance emulsability, and polymers singly
or in combination for a similar purpose, e.g. acrylic, vinyl polystyrene,
Inert fillers such as pulverized limestone powder, talc, perlite,
etc., can be used in an amount of about 0 to 50, wt. %.
Inert fibers such as cellulosic, asbestos, fiberglass, polyolefin,
etc. can be used in an amount of from about 0-25 wt. %.
It should be noted that the amount of water listed above is in
addition to that derived from asphalt and cold tar aqueous emulsions
The process of producing the aqueous emulsified bitumens are as
follows: 1. 3%-5% bentonite is added into water in the mixer. When
dispersed after mixing, it turns into a slurry. The slurry temperature
between 60-120 degrees Fahrenheit is preferred. 2. The bitumens
(asphalt coal tar or both) are heated to 250-350 degree Fahrenheit.
3. The slurry and bitumen is then combined into a mixture of emulsified
bitumen through process such as dispersing type (batch to batch)
or colloid mill type (continuous) system.
The specifications of emulsified asphalt meet ASTM D 1227, Standard
Specification for Emulsified Asphalt Used as Protective Coating
for Roofing. The Specifications of emulsified coal tar meets ASTM
D 5727 Standard Specification for Emulsified Refined Coal Tar and
ASTM D3320 Standard Specification for Emulsified Coal-Tar Pitch.
This invention will be better understood by reference to the following
The Preparation of Emulsified Asphalt Using Bentonite Slurry With
AC-250 Type Asphalt
% By weight Water 51.0 Drilling Mud Bentonite 1.5-2.5 AC-20 Asphalt
(115 deg. F. melting point) 46.3-47.3 Ph Adjuster 0.2 100.0
The Preparation of Emulsified Asphalt Using Bentonite Slurry With
PPA Hard Asphalt.
% By weight Water 51.0 Drilling Mud Bentonite Slurry 2.5-3.5 Hard
PPA Asphalt (185 deg. F. melting point) 45.3-46.3 Ph Adjuster 0.2
Preparation of Emulsified Coal Tar Using Bentonite Slurry.
% By weight Water 52.0 Drilling Mud Bentonite 7.0 Coal Tar 41.0
Preparation of Emulsified Asphalt Using Polymer(s) Added Asphalt
and Bentonite Slurry.
% By weight Water 52.0 Drilling Mud Bentonite 2.5-3.5 Asphalt with
Polymer(s) 44.3-45.3 Ph Adjusters 0.2 100.0
The following examples employ the drilling mud bentonite and bitumen
of preceding examples.
Asphalt Emulsion Roofing Composition.
% By weight Example 1 or 2 20-60 Reinforced Fibers 0.5-10 Fillers/Extenders
1.0-20 Water 0.0-20 Specialty Additives 0.1-10
Asphalt Emulsion Reflective Aluminum Composition
% By weight Example 1, 2 or 3 20-60 Special treated aluminum paste
5-15 Fillers/Extenders 2-20 Water 3-20 Specialty additives 0.2-5
Bituminous Black Top Driveway Sealers
% By weight Example 1 to 4 15-50 Fillers/Extenders 2-20 Sand 0.5-20
Water 10-40 Specialty Additives 0.2-5
Bituminous Patching Compound
% By weight Example 1 to 4 50-80 Fillers/Extenders 5-15 Fibers
1-5 Water 1-10 Specialty Additives 0.2-2.0
Bituminous Bonding Adhesives
% By weight Example 1 to 4 30-60 Adhesive Enhancer Polymer Resins
1-20 Water 1-10 Fillers/Extenders 2-10 Fibers 0.5-5 Specialty Additives
Bituminous Roof Mastic
% By weight Example 1 to 4 40-70 Bituminous Cutback Solvent 0-30
Fillers/Extenders 2-20 Specialty Additives 0.5-30
Bituminous Waterproofer or Vapor Barriers
% By weight Example 1 to 4 70-90 Wax Emulsion 0-15 Silicon Emulsion
0-15 Water 0-10 Specialty Additives 0.1-5
Primer/Weed Controller/Road Dust Suppressor
% By weight Example 1 to 4 10-50 Water 10-60 Surface Active Additives
0.3-3 Specialty Additives 0.1-6
The advantages of this invention will be apparent to the skilled
in the art higher solids emulsions, higher melt point when using
harder asphalts; no coalescing solvent needed despite high glass
transition temperature; no water sensitive surface active agents
needed; superior binding and wetting of pigments; fibers and fillers;
non porous; harder films; no setting or separation in package; excellent
wetting of substrate and adhesion to old substrates; easier more
uniform application due to their thixotropic nature; fast dry; superior
color wetness); superior hydrophobic nature, superior abrasion resistance;
superior "track" resistance (less softening when hot);
much longer useful life and weather resistance; presents good sealed
surface for recoat when necessary.
For economy of operation and ease of use, the compositions are
transported and usually marketed as concentrates. They can then
be diluted with other materials for related applications. The methods
of application are well-known and need not be elaborated here.
The present disclosure includes that contained in the appended
claims, as well as that of the foregoing description. Although this
invention has been described in its preferred form with a certain
degree of particularity, it is understood that the present disclosure
of the preferred form has been made only by way of example and that
numerous changes in the details of construction and the combination
and arrangement of parts may be resorted to without departing from
the spirit and scope of the invention.