Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Patent
1995-03-10
1996-07-02
Michl, Paul R.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
524430, 524432, 524492, 252606, C09K 2114, C09K 2100, C08K 318, C08K 322
Patent
active
055322921
DESCRIPTION:
BRIEF SUMMARY
This invention relates to intumescent compositions, and to coating compositions which incorporate such intumescent compositions and which can be applied to various substrates so as to form thereon an intumescent coating. It relates in particular to such intumescent and coating compositions which include inorganic fibres.
Intumescent coatings for providing thermal protection, flame retardation and/or smoke suppression are well known in the art. A typical coating composition for providing such a coating will include an intumescent composition and a film forming resin system.
Although the different components of the compositions will be referred to by function as though they were different materials, it should be understood that a single material may in some cases have more than one of the specified functions, either to a minor degree, so that it supplements the action of a component already provided, or to a major degree, so that it can replace or partially replace a component which would otherwise be required. Thus for example a film forming component of the resin system may itself contribute significantly to the formation of char. Furthermore the components may have other desirable properties, such as flame retardation, in addition to those primary functions specified.
Typically, the intumescent composition will comprise a catalyst (foaming agent), a carbonific or char forming agent, and a blowing agent. These are not necessarily different materials, as indicated above. Both the nature and the relative amounts (ranges) of these components are well known in the art.
The resin system will typically comprise a film forming binder. It may include a solvent, which may be either an organic solvent or water, but solvent free systems, e.g. for powder coating, are also possible.
The intumescent composition may optionally include other components such as pigments. In an intumescent coating composition, pigments may be considered to be part of the intumescent composition, or as components additional thereto.
Typical catalysts and/or foaming agents are monoammonium phosphate, diammonium phosphate, ammonium polyphosphate, potassium tripolyphosphate, or combinations thereof. Typical charring agents are pentaerythritol, dipentaerythritol, polyols, chlorinated paraffins, and combinations thereof. Typical blowing agents include melamine resins, urea, dicyandiamide and combinations thereof. An intumescent composition will typically comprise 10 to 55 parts by weight of catalyst, 4 to 35 parts by weight of char forming agent, and 5 to 40 parts by weight of blowing agent.
A typical intumescent coating composition will comprise the intumescent composition, 1 to 50 weight percent of film forming binder, 10 to 60 weight percent of solvent, and up to 40 weight percent of pigment. The film forming binder could be, for example polyvinyl acetate, acrylic resin, silicone resin, an epoxy, polyurethane, or a combination thereof. Typical organic solvents therefor are alcohols, naphthas, aromatic hydrocarbons and combinations thereof, and typical pigments include titanium oxide, zinc oxide, silicates, carbon black, lamp black, phthalocyanine blue or green, fillers such as calcium carbonate or barytes, or combinations thereof.
Elevated temperatures cause the intumescent coating both to decompose to form bubbles of gas, or vapour (for example steam), which cause the coating to swell, and to char. The resulting expanded char provides good thermal insulation and protection for the underlying substrate, but for efficient protection it is vital to have an expanded char which maintains its integrity and has a degree of mechanical strength, e.g. as measured by resistance to crushing. To this end the intumescent composition may comprise improving agents which increase the efficiency with which the composition provides protection. Typical improving agents include materials such as zinc borate; alumina trihydrate (ATH); magnesium hydroxide (synthetic or natural brucite), or any other thermally decomposable magnesium containing mineral (for example h
REFERENCES:
patent: 3284216 (1966-11-01), Kaplan
patent: 3668121 (1972-06-01), Masciantonio et al.
patent: 3726829 (1973-04-01), Sayles
patent: 3733289 (1973-05-01), Burns et al.
patent: 3969291 (1976-07-01), Fukuba
patent: 4526605 (1985-07-01), Frank
patent: 4645782 (1987-02-01), Redfarn
patent: 4695619 (1987-09-01), Hamermesh
patent: 4879320 (1989-11-01), Hastings
patent: 5356568 (1994-10-01), Levine
Evans Kenneth A.
Wainwright Robin
Alcan International Limited
DeWitt LaVonda R.
Michl Paul R.
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