Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Reexamination Certificate
2000-03-29
2002-06-25
Dawson, Robert (Department: 1712)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
C524S858000, C524S860000, C524S863000, C525S403000, C525S476000, C528S017000, C528S033000, C528S034000, C528S038000, C528S901000
Reexamination Certificate
active
06410640
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a one-pack type curable resin composition containing a polymer having reactive silicon group. More particularly, it relates to a one-pack type curable resin composition which remains stable over a long period of time in a sealed state but cures upon exposure to moisture to give a rubbery substance.
BACKGROUND OF THE INVENTION
Generally known curing resin compositions are classified into one-pack type curable resin compositions which remain stable in a sealed state but cure when exposed to moisture and two-pack ones which cure by mixing the main agent with a curing agent at a definite ratio before using. The one-pack type curable resin compositions possess a large advantage over the two-pack ones that no complicated mixing operation is needed.
As these one-pack type curable resin compositions, there have been already known curable resin compositions containing organic polymers having silicon-containing groups (hereinafter also referred to as reactive silicon groups) which have hydroxyl group and/or hydrolyzable group bonded to a silicon atom and can be crosslinked by forming a siloxane bond in the presence of moisture.
As examples of these organic polymers having reactive silicon groups to be used in the one-pack type curable resin compositions, JP-A-52-73998 and JP-5-125272 disclose polyoxyalkylene polymers having reactive silicon group which have been already produced industrially and employed in various curable resin compositions (the term “JP-A” as used herein means an “unexamined published Japanese patent application”).
When exposed to moisture in the atmosphere, curable resin compositions containing organic polymers having reactive silicon group cure to give rubbery substances. By taking advantage of this characteristic, these compositions are usable in, for example, constructional sealants, adhesives and coating materials.
The curable resin compositions to be used in sealants, adhesives and coatings and the rubbery cured substances obtained by curing these compositions should have various characteristics. In particular, adhesiveness to substrates and restoring properties are important factors, in addition to mechanical characteristics such as modulus, breaking elongation and breaking strength. Thus, a number of studies have been made hitherto on curable resin compositions containing organic polymers having reactive silicon group.
As the results of these studies, it has been already clarified that mechanical properties (for example, modulus, breaking elongation and breaking strength) adequate for various uses can be obtained by adding plasticizers such as phthalates to curable resin compositions.
As JP-B-62-35421 proposes, it has been also known that a high adhesive strength to various substrates can be achieved by adding silane coupling agents (for example, aminosilane) to these compositions (the term “JP-B” as used herein means an “examined Japanese patent publication”).
Moreover, JP-B-61-60867 (corresponding to U.S. Pat. No. 4,507,469 and European Patent 0877541) indicates that curable resin compositions having remarkably improved restoring properties can be presented by using stannous organic carboxylates as a curing catalyst.
Based on these ordinary techniques, the present inventors have made studies on a one-pack type curable resin composition containing a compound having reactive silicon group in its molecule (for example, aminosilane) as an adhesiveness imparting agent, a stannous catalyst as a curing catalyst and a plasticizer (for example, a phthalate) to give a one-pack type curable resin composition satisfying all of the needs for mechanical characteristics, adhesiveness to substrates and restoring properties. As a result, they have found out that the thus obtained composition suffers from a serious problem that the catalytic activity is considerably deteriorated and thus the curing speed is largely lowered after storing.
Accordingly, an object of the invention is to provide a one-pack type curable resin composition which satisfies all of the needs for mechanical characteristics, adhesiveness to substrates and restoring properties and suffers from no deterioration in the catalytic activity during storage.
SUMMARY OF THE INVENTION
The present inventors have conducted intensive studies to solve the problems as described above. As a result, they have found out that a decrease in the activity and/or inactivation of a curing catalyst are caused not by the adsorption of the catalyst species by an inorganic filler or the denaturation thereof, as having been assumed in general, but by a completely different phenomenon, thereby solving the problem. That is to say, they have surprisingly found out a novel fact that in a case where a stannous curing catalyst exists together with a phthalate plasticizer or a hydrolyzable silyl group-containing compound, no decrease in the activity is observed regardless of the presence of an inorganic filler, while the activity of a stannous curing catalyst is deteriorated in a case where the stannous curing catalyst exists together with a phthalate plasticizer and a hydrolyzable silyl group-containing compound due to a reaction in which these three reactants participate. Based on this finding, the present inventors have successfully found out that a one-pack type curable resin composition having a high storage stability (i.e., suffering from no decrease in the catalytic activity during storage) can be obtained by using a non-phthalate plasticizer having no phthalate structure in its molecule as a plasticizer to be used in controlling the viscosity and mechanical characteristics of the one-pack type curable resin composition in the presence of a stannous curing catalyst employed as curing catalyst and a hydrolyzable silyl group-containing compound for imparting, for example, adhesiveness to the composition. The invention has been thus achieved.
Accordingly, the invention relates to a one-pack type curable resin composition which contains an organic polymer (a) having at least one reactive silicon group per molecule, a compound (b) having reactive silicon group in its molecule, a non-phthalate plasticizer (c) having no phthalate structure in its molecule, and a stannous curing catalyst (d).
In a preferred embodiment of the invention, it relates to the one-pack type curable resin composition as described above wherein the reactive silicon group in the organic polymer (a) having at least one reactive silicon group per molecule is an alkoxysilyl group.
In a still preferred embodiment of the invention, it relates to the one-pack type curable resin composition as described above wherein the compound (b) having reactive silicon group in its molecule is an amino group-containing silane compound (e).
In a still preferred embodiment of the invention, it relates to the one-pack type curable resin composition as claimed in claim
1
, wherein the non-phthalate plasticizer (c) is at least one selected from the group consisting of an aliphatic dibasic acid ester, a glycol ester, a aliphatic ester, a phosphate, epoxidized plasticizer, an ester plasticizer, a polyether plasticizer, a polystyrene, a hydrocarbon plasticizer, and a chlorinated paraffin.
In a still preferred embodiment of the invention, it relates to the one-pack type curable resin composition as described above wherein the non-phthalate plasticizer (c) is a polyether plasticizer and/or a hydrocarbon plasticizer.
In a still preferred embodiment of the invention, it relates to the one-pack type curable resin composition as described above wherein the stannous curing catalyst (d) is at least one member selected from the group consisting of stannous octylate, stannous stearate, stannous naphthenate and stannous versatate.
DETAILED DESCRIPTION OF THE INVENTION
The organic polymer (a) having at least one reactive silicon group per molecule to be used in the invention is not restricted in the main chain skeleton. Namely, use can be made therefor of those having various main chain skeletons.
Particular examples of the organic polymer (a) include poly
Ando Hiroshi
Fukunaga Atsushi
Kawakubo Fumio
Masaoka Yoshiteru
Dawson Robert
Kaneka Corporation
Robertson Jeffrey B.
LandOfFree
One-pack type curable resin composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with One-pack type curable resin composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and One-pack type curable resin composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2978932