Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Cellular products or processes of preparing a cellular...
Reexamination Certificate
1999-12-30
2003-08-26
Seidleck, James J. (Department: 1711)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Cellular products or processes of preparing a cellular...
C521S106000, C521S085000, C521S089000, C521S120000, C521S159000, C521S168000
Reexamination Certificate
active
06610756
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an inorganic/organic composite foam and a process for producing the same. More particularly, the present invention relates to an inorganic/organic composite foam that has an inorganic foam structure, is reduced in brittleness significantly due to an elastic polymer, is in no way inferior to foams having good flexibility and rebound resilience such as polyurethane or polystyrene foams, and has a fire-proofing performance; and to a process for producing an inorganic/organic composite foam that can be formed under the conditions of room temperature and normal pressure.
BACKGROUND ART
Traditionally, foams of phosphoric acid compounds have been proposed as inorganic foams that can be formed under the conditions of room temperature and normal pressure (e.g. JP 56-36145 B).
The foam described in this publication is obtained by mixing and stirring a phosphoric acid compound, such as a metal phosphate, and a blowing agent, such as a multivalent metal carbonate, and thereby foaming and curing the mixture. This foam may be used not only in shaped materials such as panels, but also in unshaped materials for filling open spaces. It is regarded as an excellent material different from conventional foams, because of the following characteristics:
(1) The obtained foam is excellent in non-combustibility and fireproof property.
(2) The specific gravity of the foam can be controlled easily in a wide range in the production of the foam.
(3) The foam has a self-blowing property.
However, the foam of a phosphoric acid compound is a complete inorganic material and thus has brittleness. Therefore, there has been a drawback that its cells may be destroyed even with a little external force, and cannot be restored. Particularly, when a large panel having a low specific gravity is made from a foam of a phosphoric acid compound, there are problems, for example, that a mere touch may destroy its surface layer, or that the strength of the panel is too low to carry the panel. Thus, it has never been a suitable material that stands for practical uses.
In order to overcome such a drawback in a foam of a phosphoric acid compound, a method of further adding an urethane prepolymer to the raw material composition has been proposed (e.g. JP 9-157061 A).
In this method, in the case of a foam with a high blowing ratio, by the use of the urethane prepolymer, in spite of being an inorganic/organic composite, the foam can have good flexibility and rebound resilience just like a flexible polyurethane foam. Furthermore, the foam can obtain various properties from soft to hard depending on the composition of the urethane prepolymer used, and brittleness can be reduced significantly in both soft and hard foams.
Thus, by the use of the urethane prepolymer, the brittleness of the foam with a high blowing ratio is reduced, and further, the foam can have good flexibility and rebound resilience just like a flexible polyurethane foam. Moreover, the quantities of heat of combustion and smoking in combustion can be much decreased than in the cases of the organic foams. However, because the foam has a low strength after combustion, it may collapse when it is exposed to a flame for a long time.
SUMMARY OF INVENTION
It is an object of the present invention to solve these problems and provide a foam excellent in avoiding disaster, which has an improved strength after combustion and can delay the spreading of fire, by adding a powdery boric acid compound to a foam obtained from a phosphoric acid compound and/or a sulfuric acid compound that has a reduced brittleness due to a cured material of an urethane prepolymer, while retaining inherent foam properties and inherent low quantities of heat of combustion and smoking in combustion, and a process for producing the same.
That is, the present invention provides an inorganic/organic composite foam that has a foam structure obtained from a phosphoric acid compound (a1) and/or a sulfuric acid compound (a2) with a blowing agent (b), is reduced in brittleness due to a cured material of an urethane prepolymer (c) having NCO groups, and contains a powdery boric acid compound (d); and a process for producing an inorganic/organic composite foam comprising mixing components comprising a phosphoric acid compound (a1) and/or a sulfuric acid compound (a2), a blowing agent (b), an urethane prepolymer (c) having NCO groups, a powdery boric acid compound (d) and water, in combination with or without an inorganic filler (e), and thereby foaming and curing the mixture.
DETAIL DESCRIPTION OF THE INVENTION
The foam of the present invention is obtained by mixing components comprising the phosphoric acid compound (a1) and/or the sulfuric acid compound (a2), the blowing agent (b), the prepolymer (c), the powdery boric acid compound (d), and as needed the inorganic filler (e) so as to prepare an aqueous mixture, and thereby foaming and curing the mixture. That is, the foam of the present invention is obtained by preparing this aqueous mixture so that a foaming and curing reaction between (a1) and/or (a2) and (b), and a foaming and curing reaction between (c) and water proceed.
In the present invention, examples of the phosphoric acid compound (a1) include phosphoric acid, phosphorous acid, phosphoric anhydride, condensed phosphoric acid, multivalent metal salts of these compounds, and mixtures of two or more of these. The multivalent metal salts of phosphoric acid may be, for example, dihydrogenphosphates of multivalent metals, monohydrogenphosphates of multivalent metals, or phosphates of multivalent metals.
Furthermore, examples of the metal of the multivalent metal salts include magnesium, calcium, aluminum, zinc, barium, iron, and the like. Other than adding in the forms of multivalent metal phosphates or multivalent metal phosphites, these multivalent metal components also may be formed into multivalent metal salts by adding metal compounds that are chemically active to phosphoric acid or phosphorous acid, e.g. multivalent metal oxides such as magnesium oxide or calcium oxide, or multivalent metal hydroxides such as aluminum hydroxide, magnesium hydroxide, or calcium hydroxide, to the raw material mixture separately from phosphoric acid, phosphorous acid, and the like, and allowing the mixture to react.
Among the above examples of the phosphoric acid compound (a1), preferable are phosphoric acid, magnesium dihydrogenphosphate, calcium dihydrogenphosphate, aluminum dihydrogenphosphate, zinc dihydrogenphosphate, and mixtures of two or more of these. Particularly preferable are phosphoric acid, magnesium dihydrogenphosphate, aluminum dihydrogenphosphate, and mixtures of two or more of these.
In the present invention, examples of the sulfuric acid compound (a2) include sulfuric acid, sulfurous acid, multivalent metal salts of these compounds, and mixtures of two or more of these. The multivalent metal salts of sulfuric acid may be, for example, hydrogen sulfates of multivalent metals or sulfates of multivalent metals.
Furthermore, examples of the metals of the multivalent metal salts include magnesium, calcium, aluminum, zinc, barium, iron, and the like. Other than adding in the forms of multivalent metal sulfates or multivalent metals sulfites, these multivalent metal components also may be formed into multivalent metal salts by adding metal compounds that are chemically active to sulfuric acid or sulfurous acid, e.g. multivalent metal hydroxides such as aluminum hydroxide, magnesium hydroxide, or calcium hydroxide, to the raw material mixture separately from sulfuric acid, sulfurous acid, and the like, and allowing the mixture to react.
Among the above examples of the sulfuric acid compound (a2), preferable are sulfuric acid, calcium hydrogen sulfate, magnesium hydrogen sulfate, zinc hydrogen sulfate, aluminum hydrogen sulfate, and mixtures of two or more of these. Particularly preferable are sulfuric acid, magnesium hydrogen sulfate, calcium hydrogen sulfate, and mixtures of two or more of these.
The content of the phosphoric acid compound (a1) and/or the sulf
Kaida Shinzo
Shimizu Tomokazu
Tomosada Tsuyoshi
Yamazaki Tadaaki
Bissett Melanie
Merchant & Gould P.C.
Sanyo Checmical Industries, Ltd.
Seidleck James J.
LandOfFree
Inorganic/organic composite foam and process for producing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Inorganic/organic composite foam and process for producing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inorganic/organic composite foam and process for producing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3100035