Calcium borate
Encyclopedia
Calcium borate also called Gerstley borate is a bluish white crystal with a very defined structure. It can be prepared by reacting calcium
metal with boric acid
. The resulting precipitate is calcium borate. A hydrated form occurs naturally as the mineral
s colemanite
, nobleite
and priceite.
One of its uses is as a binder
in some grades of hexagonal boron nitride
for hot pressing
. Other uses are e.g. flame retardant
in epoxy
molding compounds, a ceramic flux
in some ceramic glaze
s, reactive self-sealing binders in hazardous waste
management, additive for insect-resistant polystyrene
, fertilizer
, and production of boron glasses
.
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
metal with boric acid
Boric acid
Boric acid, also called hydrogen borate or boracic acid or orthoboric acid or acidum boricum, is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a...
. The resulting precipitate is calcium borate. A hydrated form occurs naturally as the mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
s colemanite
Colemanite
Colemanite is a borate mineral found in evaporite deposits of alkaline lacustrine environments. Colemanite is a secondary mineral that forms by alteration of borax and ulexite....
, nobleite
Nobleite
Nobleite is a rare borate mineral with the chemical formula CaB6O92·3. It was discovered in 1961, in Death Valley, California, and is named for Levi F. Noble, a USGS geologist, in honor of his contributions to the geology of the Death Valley region....
and priceite.
One of its uses is as a binder
Binder (material)
-See also:*Adhesive or Glue*Cement*Paint...
in some grades of hexagonal boron nitride
Boron nitride
Boron nitride is a chemical compound with chemical formula BN, consisting of equal numbers of boron and nitrogen atoms. BN is isoelectronic to a similarly structured carbon lattice and thus exists in various crystalline forms...
for hot pressing
Hot pressing
Hot pressing is a high-pressure, low-strain-rate powder metallurgy process for forming of a powder or powder compact at a temperature high enough to induce sintering and creep processes. This is achieved by the simultaneous application of heat and pressure....
. Other uses are e.g. flame retardant
Flame retardant
Flame retardants are chemicals used in thermoplastics, thermosets, textiles and coatings that inhibit or resist the spread of fire. These can be separated into several different classes of chemicals:...
in epoxy
Epoxy
Epoxy, also known as polyepoxide, is a thermosetting polymer formed from reaction of an epoxide "resin" with polyamine "hardener". Epoxy has a wide range of applications, including fiber-reinforced plastic materials and general purpose adhesives....
molding compounds, a ceramic flux
Ceramic flux
A ceramic flux functions by promoting glass formation in clay bodies and glazes. Fluxes are used in glazes to lower the high melting point of silica. The most commonly used fluxes in a ceramic glaze are lead, boric, soda, potassium, lithium, calcium, magnesium, barium, zinc, and strontium...
in some ceramic glaze
Ceramic glaze
Glaze is a layer or coating of a vitreous substance which has been fired to fuse to a ceramic object to color, decorate, strengthen or waterproof it.-Use:...
s, reactive self-sealing binders in hazardous waste
Hazardous waste
A hazardous waste is waste that poses substantial or potential threats to public health or the environment. According to the U.S. environmental laws hazardous wastes fall into two major categories: characteristic wastes and listed wastes.Characteristic hazardous wastes are materials that are known...
management, additive for insect-resistant polystyrene
Polystyrene
Polystyrene ) also known as Thermocole, abbreviated following ISO Standard PS, is an aromatic polymer made from the monomer styrene, a liquid hydrocarbon that is manufactured from petroleum by the chemical industry...
, fertilizer
Fertilizer
Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
, and production of boron glasses
Borosilicate glass
Borosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are known for having very low coefficients of thermal expansion , making them resistant to thermal shock, more so than any other common glass...
.