JP7290015B1 - Two-component polyurethane sealant composition - Google Patents

Abstract

An object of the present invention is to provide a two-component polyurethane sealant composition which, when used as a sealant, exhibits excellent tensile properties, adhesion to paint, and paint contamination resistance. The composition contains a base containing a urethane prepolymer having an isocyanate group, a polyol, and a polyepoxy compound having a plurality of epoxy groups in one molecule and an epoxy equivalent weight of 100 to 200 g/eq. and a curing agent, the content of the polyepoxy compound is 2.0 to 15.0% by mass in the composition, the epoxy groups are each independently bonded to a hydrocarbon group, and the hydrocarbon A two-component polyurethane sealant composition in which the groups do not have ether linkages. [Selection figure] None

Description

The present invention relates to two-component polyurethane sealant compositions.

Conventionally, a sealant composition containing a urethane prepolymer has been proposed (for example, Patent Document 1).

JP 2008-013696 A

The present inventor prepared a composition for a two-part polyurethane sealant with reference to Patent Document 1 and evaluated it. In some cases, adhesion or stain resistance of the paint was poor.

Accordingly, an object of the present invention is to provide a two-component polyurethane sealant composition which, when used as a sealant, exhibits excellent tensile properties, adhesion to paint, and stain resistance of paint.

As a result of intensive research to solve the above problems, the inventors of the present invention have found that a two-component polyurethane sealant composition has a plurality of epoxy groups in one molecule, an epoxy equivalent weight within a specific range, and the epoxy The inventors have found that a desired effect can be obtained by containing a specific amount of a polyepoxy compound in which each group independently bonds to a hydrocarbon group that does not have an ether bond, leading to the present invention.
The present invention is based on the above knowledge and the like, and specifically solves the above problems with the following configuration.

[1] a base containing a urethane prepolymer having an isocyanate group;
A curing agent containing a polyol and a polyepoxy compound having a plurality of epoxy groups in one molecule and an epoxy equivalent of 100 to 200 g/eq,
The content of the polyepoxy compound is 2.0 to 15.0% by mass in the composition,
A two-component polyurethane sealant composition, wherein each of the epoxy groups is independently bonded to a hydrocarbon group, and the hydrocarbon group does not have an ether bond.
[2] 2 according to [1], wherein the polyepoxy compound contains at least one selected from the group consisting of epoxidized linseed oil-based compounds, epoxidized soybean oil-based compounds, and alicyclic epoxy resin compounds. A component-based polyurethane sealant composition.
[3] The two-component polyurethane sealant composition according to [1] or [2], wherein the polyepoxy compound comprises an epoxidized linseed oil compound and/or an alicyclic epoxy resin compound.
[4] The two-component polyurethane sealant composition according to any one of [1] to [3], wherein the polyepoxy compound has an epoxy equivalent of 120 to 170 g/eq.
[5] The two-component polyurethane sealant composition according to any one of [1] to [4], wherein the polyepoxy compound has an epoxy equivalent of 140 to 170 g/eq.
[6] The two-component polyurethane sealant composition according to any one of [1] to [5], wherein the curing agent further contains a terminal esterified polyether.
[7] The two-component polyurethane sealant composition according to [6], wherein the content of the terminally esterified polyether is 2.0 to 5.0% by mass in the composition.

According to the present invention, it is possible to provide a two-component polyurethane sealant composition which, when used as a sealant, exhibits excellent tensile properties, adhesion to paint, and paint contamination resistance.

The present invention will be described in detail below.
In the present specification, a numerical range represented by "-" means a range including the numerical values before and after "-".
In this specification, unless otherwise specified, each component can be used singly or in combination of two or more substances corresponding to the component. When the component contains two or more substances, the content of the component means the total content of the two or more substances.
In this specification, when at least one of tensile properties, adhesion to paint, and stain resistance of paint is superior, the effect of the present invention is said to be superior.

[Two-component polyurethane sealant composition]
The two-component polyurethane sealant composition of the present invention (the composition of the present invention) is
a base containing a urethane prepolymer having an isocyanate group;
A curing agent containing a polyol and a polyepoxy compound having a plurality of epoxy groups in one molecule and an epoxy equivalent of 100 to 200 g/eq,
The content of the polyepoxy compound is 2.0 to 15.0% by mass in the composition,
The epoxy groups are each independently bonded to a hydrocarbon group, and the hydrocarbon group does not have an ether bond.
In the present specification, the above has a plurality of epoxy groups in one molecule, the epoxy equivalent is 100 to 200 g/eq, the epoxy groups are each independently bonded to a hydrocarbon group, and the hydrocarbon group is A polyepoxy compound that does not have an ether bond is sometimes referred to as a "specific polyepoxy compound".

Since the composition of the present invention has such a constitution, it is believed that the desired effect can be obtained. Although the reason is not clear, it is presumed to be approximately as follows.
The composition of the present invention contains a specific polyepoxy compound, the content of which is 2.0 to 15.0% by mass in the composition of the present invention, whereby epoxy groups can remain in the sealant obtained, When used as a sealing material, it is presumed to have excellent tensile properties, adhesion to paint, and paint contamination resistance.
Each component contained in the composition of the present invention will be described in detail below.

The composition of the present invention has a base and a curing agent. In the present invention, curing agents mean curing agents in a broad sense. Broadly defined curing agents generally include narrowly defined curing agents (components that react with the urethane prepolymer contained in the base).

[Base]
In the present invention, the base contains a urethane prepolymer having isocyanate groups.

[Urethane prepolymer]
In the present invention, the urethane prepolymer has isocyanate groups.
A urethane prepolymer can be obtained by reacting a polyisocyanate compound with an active hydrogen group-containing compound having a plurality of active hydrogens.

(Polyisocyanate compound)
The polyisocyanate compound used in producing the urethane prepolymer is not particularly limited as long as it is a compound having two or more isocyanate groups in the molecule.
Polyisocyanate compounds include, for example, toluene diisocyanate (TDI), diphenylmethane diisocyanate (unsubstituted MDI; also referred to as pure MDI and monomeric MDI), 1,4-phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, xylylene diisocyanate (XDI ), tetramethylxylylene diisocyanate (TMXDI), tolidine diisocyanate (TODI), 1,5-naphthalenediisocyanate (NDI), triphenylmethane triisocyanate, polymeric MDI (a compound obtained by increasing the molecular weight of diphenylmethane diisocyanate (pure MDI)), Aromatic polyisocyanates such as modified MDI (for example, modified diphenylmethane diisocyanate (pure MDI), isocyanurate-modified MDI (MDI trimer), carbodiimide-modified MDI, urethane-modified MDI, etc.);
Hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornane diisocyanate (NBDI), transcyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), bis(isocyanatomethyl)cyclohexane (H ₆ XDI) , dicyclohexylmethane diisocyanate (H ₁₂ MDI), carbodiimide modified products thereof, isocyanurate modified products thereof, and other aliphatic and/or alicyclic polyisocyanates.

The polyisocyanate compound preferably contains an aromatic polyisocyanate, more preferably toluene diisocyanate (TDI), and even more preferably 2,4-TDI, from the viewpoint that the effects of the present invention are more excellent.
Examples of TDI include 2,4-TDI single compound and a mixture of 2,4-TDI and 2,6-TDI.
When TDI is a mixture of 2,4-TDI and 2,6-TDI, the mixing ratio of the mixture is, for example, 80 to 65% of 2,4-TDI and 20 to 2,6-TDI. Mixtures that are 35% are mentioned.

(active hydrogen group-containing compound)
The active hydrogen group-containing compound used in producing the urethane prepolymer is a compound having multiple active hydrogens.
The active hydrogen group-containing compound can have active hydrogen as a group having active hydrogen (active hydrogen group).
Examples of the group having active hydrogen (active hydrogen group) include a hydroxy group and an amino group.
From the viewpoint that the effects of the present invention are more excellent, the active hydrogen group-containing compound preferably contains a polyol having a plurality of hydroxy groups.

(polyol)
The polyol that can be used when producing the urethane prepolymer is not particularly limited as long as it is a compound having multiple hydroxy groups.
Polyols can have, for example, 2 to 3 hydroxy groups per molecule.

Polyols include, for example, polyether polyols, polyester polyols, and poly(meth)acrylic polyols. Among them, the polyol preferably contains a polyether polyol.
Polyether polyols include, for example, polyoxyethylene polyols, polyoxypropylene polyols, and polyols of ethylene oxide/propylene oxide copolymers.
Among them, the polyol preferably contains polyoxypropylene diol and/or polyoxypropylene triol, and more preferably contains polyoxypropylene diol and polyoxypropylene triol, from the viewpoint that the effect of the present invention is more excellent. More preferably, it contains a polyoxypropylene diol with a weight average molecular weight of 2,000 to 5,000 and a polyoxypropylene triol with a weight average molecular weight of 3,000 to 5,000.

(monool)
When producing a urethane prepolymer, a monol having one hydroxy group can be used in addition to the above polyols.
From the viewpoint that the effect of the present invention is more excellent, it is preferable to further use a monol in addition to the above polyol.
The above-mentioned monol preferably contains polyoxypropylene monool, and more preferably contains monool in which a hydroxyl group at one end of polyoxypropylene diol is blocked with a hydrocarbon group. The hydrocarbon group is not particularly limited. The above hydrocarbon group can form a hydrocarbon group —O— in the monool.
The monol preferably comprises a polyoxypropylene monol having a weight average molecular weight of 3,000-4,000.
From the viewpoint that the effect of the present invention is more excellent, the amount of monool is preferably 10 to 15 mass % of the total amount of polyol and monool.
The amount of hydroxy groups possessed by the monool is preferably 5 to 10 mol % of the total amount of hydroxy groups possessed by the polyol and hydroxy groups possessed by the monool, from the viewpoint that the effects of the present invention are more excellent.

In the present invention, the weight average molecular weight of the polyol or monool can be a standard polyether polyol conversion value measured by gel permeation chromatography (GPC) under the following conditions.
・Solvent: Tetrahydrofuran ・Detector: RI detector

(oxazolidine compound)
The base preferably further contains an oxazolidine compound from the viewpoint that the effects of the present invention are more excellent and the curing speed can be increased.

Oxazolidine compounds include, for example, N-hydroxyalkyloxazolidines.
The number f of hydroxyl groups in one molecule of the oxazolidine compound is preferably 1-2.
The number f of amines (nitrogen atoms of the oxazolidine ring) in one molecule of the oxazolidine compound is preferably 1-2.

N-Hydroxyalkyloxazolidines can be prepared, for example, by a dehydration condensation reaction between alkanolamines and ketones or aldehydes.
Examples of N-hydroxyalkyloxazolidine include 3-(2-hydroxyethyl)-2-(1-methylbutyl)oxazolidine (PHO), 2-isopropyl-3-(2-hydroxyethyl)oxazolidine, 2-(1- 3-(hydroxyalkyl)-2-(alkyl)oxazolidines such as methylbutyl)-3-(2-hydroxypropyl)-5-methyloxazolidine; 2-phenyl-3-(2-hydroxyethyl)oxazolidine, 2- (p-Methoxyphenyl)-3-(2-hydroxyethyl)oxazolidine.

The oxazolidine compound preferably contains 3-(hydroxyalkyl)-2-(alkyl)oxazolidine, 3-(2-hydroxyethyl)-2-(1-methylbutyl), from the viewpoint that the effects of the present invention are more excellent. More preferably it contains an oxazolidine.

The amount of the oxazolidine compound is preferably 0.2 to 0.5% by mass of the total amount of the polyisocyanate compound and the active hydrogen group-containing compound, from the viewpoint that the effects of the present invention are more excellent.

(Preparation of urethane prepolymer)
Examples of methods for preparing urethane prepolymers include:
The index (molar ratio) of the isocyanate group of the polyisocyanate compound to the active hydrogen group of the active hydrogen group-containing compound (group having active hydrogen, e.g., hydroxy group) (e.g., activity When the hydrogen group is a hydroxy group, the above Index is also expressed as "NCO/OH") is reacted in an amount of more than 1.5 and less than 2.
A method of obtaining a urethane prepolymer by blending an oxazolidine compound with the reaction product obtained above can be mentioned.
When a monool is further used in the preparation of the urethane prepolymer, the hydroxy group possessed by the monool is added to the active hydrogen group in calculating the Index.
In the above preparation method, a plasticizer such as diisononyl adipate can also be used. The plasticizer is preferably inactive with respect to the polyisocyanate compound, the active hydrogen group-containing compound and the oxazolidine compound.
The urethane prepolymer obtained after preparation can be used as a base.
The urethane prepolymer may contain, for example, a plasticizer.

In addition, plasticizers that can be contained in the urethane prepolymer include, for example, the plasticizers used in producing the urethane prepolymer.
When the urethane prepolymer contains a plasticizer, the amount of the plasticizer in the total amount of the urethane prepolymer is preferably 5.0 to 10.0% by mass, from the viewpoint that the effects of the present invention are more excellent.

(Isocyanate group content of urethane prepolymer)
The isocyanate group content (NCO %) of the urethane prepolymer is preferably 2.9 to 3.1% by mass in the base, from the viewpoint that the effect of the present invention is more excellent.

(Remaining amount of unreacted polyisocyanate compound in urethane prepolymer)
The residual amount of the unreacted polyisocyanate compound (the unreacted polyisocyanate compound itself used as a raw material) in the urethane prepolymer is 1.0 in the urethane prepolymer from the viewpoint that the effect of the present invention is more excellent. Less than mass % is preferred.
When the urethane prepolymer contains a plasticizer, the residual amount of the unreacted polyisocyanate compound in the urethane prepolymer is the total amount of the urethane prepolymer and the plasticizer, from the viewpoint that the effects of the present invention are more excellent. Less than 1.0% by mass is preferred.

(Content of urethane prepolymer in the composition of the present invention)
The content of the urethane prepolymer is preferably 15 to 30% by mass, more preferably 15 to 20% by mass, of the composition (total amount) of the present invention.
When the urethane prepolymer contains a plasticizer, the total content of the urethane prepolymer and the plasticizer is preferably 15 to 30% by mass, more preferably 15 to 20% by mass, of the composition (total amount) of the present invention. is more preferred.

[Curing agent]
The curing agent (curing agent in a broad sense) of the composition of the present invention contains a polyol and a specific polyepoxy compound.

[Polyol]
In the present invention, the polyol contained in the curing agent (curing agent in a broad sense) is not particularly limited as long as it is a compound having multiple hydroxy groups.
The polyol contained in the curing agent (broadly defined curing agent) can function as a component (narrowly defined curing agent) that reacts with the urethane prepolymer.
The polyol preferably has 2 to 3 hydroxy groups per molecule.

Examples of the polyols include polyether polyols, polyester polyols, and poly(meth)acrylic polyols. Among them, the polyol preferably contains a polyether polyol.
Polyether polyols include, for example, polyoxyalkylene polyols such as polyoxyethylene polyols, polyoxypropylene polyols, polyols of ethylene oxide/propylene oxide copolymers.
Among them, the polyol preferably contains polyoxypropylene diol and/or polyoxypropylene triol, and more preferably contains polyoxypropylene diol and polyoxypropylene triol, from the viewpoint that the effects of the present invention are more excellent. , a polyoxypropylene diol having a weight average molecular weight of 2,000 to 5,000 and a polyoxypropylene triol having a weight average molecular weight of 3,000 to 10,000.

When the polyol contains polyoxypropylene diol and polyoxypropylene triol, the content of polyoxypropylene diol is 20 to 25 in the total amount of the curing agent (curing agent in a broad sense) from the viewpoint that the effect of the present invention is more excellent. % by weight is preferred.
When the polyol contains polyoxypropylene diol and polyoxypropylene triol, the content of polyoxypropylene triol is 5.0 in the total amount of the curing agent (curing agent in a broad sense) from the viewpoint that the effect of the present invention is more excellent. ~10.0% by mass is preferred.

[Specific polyepoxy compound]
In the present invention, the specific polyepoxy compound contained in the curing agent (curing agent in a broad sense) is a polyepoxy compound having a plurality of epoxy groups in one molecule and an epoxy equivalent of 100 to 200 g/eq. In the polyepoxy compound, the epoxy groups are each independently bonded to a hydrocarbon group, and the hydrocarbon groups do not have an ether bond.

[Multiple epoxy groups in one molecule]
In the present invention, the specific polyepoxy compound has multiple epoxy groups in one molecule.
The specific polyepoxy compound preferably has 2 to 10 epoxy groups in one molecule from the viewpoint that the effects of the present invention are more excellent.

[Epoxy equivalent]
In the present invention, the epoxy equivalent of the specific polyepoxy compound is 100-200 g/eq.
The specific polyepoxy compound preferably contains a polyepoxy compound having an epoxy equivalent of 120 to 170 g/eq from the viewpoint that the effect of the present invention is more excellent. It is more preferable to include
The epoxy equivalent of the specific polyepoxy compound can be the catalog value of the specific polyepoxy compound when the specific polyepoxy compound is a commercial product.

[Each epoxy group independently binds to a hydrocarbon group]
In the present invention, the epoxy groups possessed by the specific polyepoxy compound are each independently bonded to a hydrocarbon group.
In the specific polyepoxy compound, the epoxy group reacts with the urethane prepolymer and/or the polyol without intervening (participating) in the reaction between the urethane prepolymer contained in the base and the polyol contained in the curing agent. The two carbon atoms constituting the epoxy group are bonded to different hydrocarbon groups, respectively, from the viewpoint that the epoxy group can remain when used as a sealant, and the effect of the present invention is more excellent. is preferred. In a specific polyepoxy compound, when two carbon atoms constituting an epoxy group are respectively bonded to different hydrocarbon groups, the epoxy group can exist inside the specific polyepoxy compound. Being present at the end of the polyepoxy compound is excluded.
Examples of the embodiment in which the two carbon atoms constituting the epoxy group are bonded to different hydrocarbon groups include, for example, the embodiment in which the two carbon atoms constituting the epoxy group are respectively bonded to different aliphatic hydrocarbon groups, An embodiment in which the above-mentioned separate aliphatic hydrocarbon groups are bonded to each other to form a ring structure is exemplified.
Examples of the aliphatic hydrocarbon group include an alkyl group and an alkylene group, and specific examples include an alkyl group having 1 to 10 carbon atoms and an alkylene group having 1 to 10 carbon atoms.
Examples of the ring structure include a cyclohexane ring.

(ester bond)
The specific polyepoxy compound may further have an ester bond in addition to the epoxy group and the aliphatic hydrocarbon group.

[Ether bond]
In the specific polyepoxy compound, the hydrocarbon groups attached to the epoxy groups do not have ether linkages. That is, the specific polyepoxy compound does not include compounds such as glycidyl ether groups, in which hydrocarbon groups bonded to epoxy groups form ether bonds.

(Example of specific polyepoxy compound)
The specific polyepoxy compound does not intervene (participate in) the reaction between the urethane prepolymer contained in the base and the polyol contained in the curing agent, does not easily react with the urethane prepolymer and/or the polyol, and is used as a sealant. The group consisting of epoxidized linseed oil-based compounds, epoxidized soybean oil-based compounds, and alicyclic epoxy resin compounds from the viewpoint that the effect of the present invention is more excellent because the epoxy group can be left when it becomes It preferably contains at least one selected from, and more preferably contains an epoxidized linseed oil-based compound and/or an alicyclic epoxy resin compound.
When the specific polyepoxy compound is an epoxidized linseed oil-based compound, an epoxidized soybean oil-based compound, or an alicyclic epoxy compound, these have a large molecular structure or large steric hindrance, making it difficult to migrate to the paint. It is thought that the stain resistance (of the paint) is further improved.

(epoxidized linseed oil-based compound)
The epoxidized linseed oil-based compound is a compound obtained by epoxidizing linseed oil.
Examples of epoxidized linseed oil-based compounds include epoxidized linseed oil-based compounds containing compounds represented by the following structures.

(epoxidized soybean oil-based compound)
An epoxidized soybean oil-based compound is a compound obtained by epoxidizing soybean oil.
Examples of epoxidized soybean oil-based compounds include epoxidized soybean oil-based compounds containing compounds represented by the following structures.

(Alicyclic epoxy resin compound)
Examples of alicyclic epoxy resin compounds include compounds represented by the following structures.

(Number average molecular weight of specific polyepoxy compound)
The number average molecular weight of the specific polyepoxy compound is preferably 200 to 1,000 from the viewpoint that the effects of the present invention are more excellent.
In the present invention, the number average molecular weight of the specific polyepoxy compound can be a standard polystyrene conversion value of gel permeation chromatography (GPC) measurement under the following conditions.
・Solvent: Tetrahydrofuran ・Detector: RI detector

Specific polyepoxy compounds include, for example,
An epoxidized linseed oil-based compound having a functional group f of epoxy groups per molecule of f = 6, an epoxy equivalent of 150 to 160 g/eq, and a number average molecular weight of about 950,
an epoxidized soybean oil-based compound having an epoxy functional group f of 5 per molecule, an epoxy equivalent of 180 to 190 g/eq, and a number average molecular weight of about 920;
An alicyclic epoxy resin compound having an epoxy group condensed to a cyclohexane ring in one molecule with a functional group number of f=2, an epoxy equivalent of 120 to 140 g/eq, and a number average molecular weight of about 252 can be mentioned. The combination of the functional group f of the epoxy group, the epoxy equivalent, and the number average molecular weight in each specific polyepoxy compound is not limited to the above.

[Content of specific polyepoxy compound]
In the present invention, the content of the specific polyepoxy compound is 2.0 to 15.0% by mass in the composition (total amount) of the present invention.
When the specific polyepoxy compound contains an epoxidized linseed oil-based compound, the content of the specific polyepoxy compound containing the epoxidized linseed oil-based compound is 2.0 to 15.0% in the composition (total amount) of the present invention. It can be 0% by mass.
When the specific polyepoxy compound contains an epoxidized soybean oil-based compound, the content of the specific polyepoxy compound containing the epoxidized soybean oil-based compound is 5.0 to 15.0% in the composition (total amount) of the present invention. It can be 0% by mass.
When the specific polyepoxy compound contains an alicyclic epoxy resin compound, the content of the specific polyepoxy compound containing the alicyclic epoxy resin compound is 2.0 to 10.0% in the composition (total amount) of the present invention. It can be 0% by mass.
The content of the specific polyepoxy compound is preferably 2.0 to 5.0% by mass in the composition (total amount) of the present invention from the viewpoint that the effect of the present invention is more excellent.

(Terminal esterified polyether)
From the viewpoint that the effects of the present invention are more excellent, the curing agent preferably further contains a terminal esterified polyether.
The terminal esterified polyether is a compound in which the hydroxy groups of polyether are esterified. The ester residue resulting from the above esterification is not particularly limited. Examples include hydrocarbon groups.
Terminally esterified polyethers include, for example, terminally esterified polyoxyalkylenes.
From the viewpoint that the effect of the present invention is more excellent, the terminal esterified polyether preferably contains a compound in which all the hydroxy groups are esterified in a polyether having a plurality of hydroxy groups at its terminals, and a plurality of hydroxy groups It preferably contains a compound in which all the above hydroxy groups are esterified in a polyoxyalkylene terminated with

(Content of terminal esterified polyether)
When the curing agent further contains a terminal esterified polyether, the content of the terminal esterified polyether is 2.0 to 5 in the composition (total amount) of the present invention from the viewpoint that the effect of the present invention is more excellent. 0% by mass is preferred.
Further, when the curing agent further contains a terminal esterified polyether, the content of the specific polyepoxy compound is 2.0 to 2.0 in the composition (total amount) of the present invention, from the viewpoint that the effect of the present invention is more excellent. It is preferably 5.0% by mass.

(catalyst)
The curing agent can further contain a catalyst.
The catalyst is not particularly limited as long as it is a compound capable of promoting the reaction between the urethane prepolymer in the base and the polyol in the curing agent.
From the viewpoint that the effect of the present invention is more excellent, the catalyst is an organic bismuth salt carboxylic acid (a salt of an organic carboxylic acid and bismuth) and/or an organic zinc salt carboxylic acid (a salt of an organic carboxylic acid and zinc). It preferably contains an organic bismuth salt carboxylic acid and an organic zinc salt carboxylic acid, more preferably.
The organic carboxylic acid capable of forming an organic bismuth salt carboxylic acid or an organic zinc salt carboxylic acid is not particularly limited as long as it is a hydrocarbon compound having a carboxy group.
When the curing agent further contains a catalyst, the content of the catalyst is preferably 0.5 to 1.0% by mass of the composition (total amount) of the present invention from the viewpoint that the effects of the present invention are more excellent.

(filler)
The curing agent can further contain fillers.
Examples of fillers include calcium carbonate such as heavy calcium carbonate and light calcium carbonate; and titanium oxide. As for the filler, it is preferable to use both calcium carbonate and titanium oxide.
The filler may be surface treated with a surface treatment agent such as saturated fatty acid or unsaturated fatty acid.
When calcium carbonate is used as a filler, calcium carbonate is preferably used in combination with, for example, heavy calcium carbonate and surface-treated light calcium carbonate.
When the curing agent further contains a filler, the content of the filler is preferably 45 to 60% by mass of the composition (total amount) of the present invention from the viewpoint that the effects of the present invention are more excellent.

(organic hollow balloon)
The curing agent can further contain organic hollow balloons.
An organic hollow balloon is a balloon made of an organic substance, and is a hollow body in which the inside of the balloon is hollow. There are no particular restrictions on the organic substance that constitutes the organic hollow balloon.
The organic hollow balloons preferably contain organic hollow balloons having a specific gravity ρ of 0.09 to 0.15 from the viewpoint that the effect of the present invention is more excellent.
When the curing agent further contains organic hollow balloons, the content of the organic hollow balloons is 3.0 to 4.0% by mass in the composition (total amount) of the present invention from the viewpoint that the effect of the present invention is more excellent. is preferred.
When the curing agent further contains organic hollow balloons, the mixing specific gravity ρ of the base and the curing agent is preferably 0.90 to 1.10. The mixed specific gravity ρ of the base and the curing agent (the specific gravity of the uncured product) can be measured according to JIS K 7112 A method (substitution in water).

(Preparation of curing agent)
The curing agent can be prepared, for example, by mixing the essential components described above with a catalyst or the like that can be further used as necessary.

(other ingredients)
The composition of the present invention may further contain additives, if necessary, as long as the objects of the present invention are not impaired. Examples of the additives include anti-aging agents and paraffin solvents. The amount of additive can be determined appropriately. Each of the above additives can be added, for example, to the curing agent.

The composition of the present invention is a two-component composition having a base and a curing agent.
The composition of the invention can be used as a composition for polyurethane sealants.

(how to use)
When using the composition of the present invention, the base and the curing agent may be mixed.
(molar ratio of isocyanate groups of the urethane prepolymer in the base to hydroxy groups of the polyol in the curing agent)
From the viewpoint that the effect of the present invention is more excellent, the molar ratio of the isocyanate groups of the urethane prepolymer in the base to the hydroxyl groups of the polyol in the curing agent (NCO group/OH group molar ratio, mixture index) is 1. It is preferably more than 0.0 and 1.2 or less (NCO group; more than 1.0 to 1.2 or less/OH group 1.0).
When mixing the base and the curing agent, the mass ratio of the base and the curing agent is not particularly limited, and the above mass ratio is used in designing the sealant obtained from the composition of the present invention. It can be adjusted arbitrarily. As the mass ratio, the base and the curing agent can be mixed at a mass ratio of 100:450, for example. When adjusting the mass ratio, it is preferable to set the Mixed Index to more than 1.0 and not more than 1.2.

(adherend)
Examples of adherends to which the composition of the present invention can be applied include anodized aluminum, cement, mortar, ALC (light cellular concrete), and slate.
The method of applying the composition of the present invention to an adherend is not particularly limited. For example, a conventionally known method can be used.

(Curing conditions for the composition of the present invention)
The compositions of the invention can be cured by mixing the base and the curing agent.
Curing conditions include, for example, a relative humidity of 20 to 80% RH and a temperature of 5 to 45°C.
The composition of the present invention can serve as a sealant containing polyurethane and a specific polyepoxy compound produced by reacting a urethane prepolymer contained in a base with a polyol contained in a curing agent.
In the present invention, the specific polyepoxy compound does not intervene (be involved in) the reaction between the urethane prepolymer contained in the base and the polyol contained in the curing agent. And it is preferred that it does not react or hardly reacts with the polyol contained in the curing agent. Since the specific polyepoxy compound does not participate in the reaction between the urethane prepolymer and the polyol, it is believed that the above reaction does not impair the tensile properties of the polyurethane.
The composition of the present invention can contain the epoxy groups in the specific polyepoxy compound in an unreacted state (as epoxy groups) after becoming a sealant.

(paint)
A coating can be applied over the composition of the invention (eg, over the composition of the invention applied to an adherend).
After curing, the composition of the present invention can contain the specific polyepoxy compound in the sealant obtained as described above, and thus has excellent adhesion to paint.
There are no particular restrictions on the paint. Examples thereof include conventionally known paints.
The paint is preferably an epoxy-based paint from the viewpoint that the composition of the present invention has better adhesion to the sealant and stain resistance of the paint. The epoxy-based paint reacts with the epoxy groups in the specific polyepoxy compound contained in the sealant formed using the composition of the present invention to bond and fix the specific polyepoxy compound to the paint. It is considered to be for
Paints include, for example, paints having a topcoat and a primer.

EXAMPLES The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these.

<Production of base (urethane prepolymer)>
In the production of the base (urethane prepolymer), each component shown in the "base component 1" column of Table 1 below was used in the amount (parts by mass) shown in the same table.
In a synthesizer, component 1a and plasticizer (DINA) are dehydrated under conditions of 110°C for 6 hours, then component 1b is added thereto and reacted under conditions of 90°C for 14 hours. Component 1c was added and stirred at 50° C. for 1 hour to obtain a base. At that time, the index (NCO/OH: molar ratio) of component 1a and component 1b was 1.98/1.0. Incidentally, "79.4" parts by mass in Table 1 is the total amount of polypropylene glycols 1-3.
The base prepared as described above is a mixture containing a urethane prepolymer and DINA as a plasticizer.
The isocyanate group content of the obtained urethane prepolymer (including the plasticizer) was 3.00% by mass in the urethane prepolymer (including the plasticizer) (before consumption of component 1c. The base was cured. Urethane prepolymers do not react with oxazolidine compounds such as component 1c in the base unless they are mixed in the agent.). The isocyanate group content of the urethane prepolymer after the urethane prepolymer reacts with component 1c is 2.80% by mass in the urethane prepolymer (after component 1c is consumed).
The residual amount of the unreacted polyisocyanate compound in the obtained urethane prepolymer (including the plasticizer) was 0.87% by mass in the urethane prepolymer (including the plasticizer).

<Production of curing agent>
As shown in the "Production of curing agent" column in Table 2, each component shown in the "Curing agent component 2" column in Table 2 was used in the amount (parts by mass) shown in the same table.
First, the components from component 2a to the isoparaffinic solvent shown in Table 2 below were charged into a planetary mixer, mixed at room temperature for 40 minutes, and then the remaining components shown in Table 2 below were added. These were mixed for 30 minutes to produce each curing agent.
Table 3 shows the details of the "curing agent component 2" column in Table 2.

<Production of composition>
As shown in the "manufacture of composition" column in Table 2, 100 parts by mass of the base prepared as described above and 450 parts by weight of each curing agent prepared as described above were mixed with a stirrer, and each composition manufactured things.

<Evaluation>
The following evaluations were performed using each composition produced as described above. The results are shown in Table 2.
<Tensile properties>
An anodized aluminum plate was used as an adherend. Primer No. 1 was applied to the surface of the anodized aluminum plate. 40: Sika Hamatite Co., Ltd. is applied in advance.
According to JIS A 1439: 5.20 tensile adhesion test of 2010, each composition prepared as described above was applied on the primer to prepare each sample, and after curing (curing conditions: 23 ° C. × 7 50% modulus (N/mm ² ), maximum tensile stress (N/mm ² ) and elongation at maximum load (%) are measured by tensile adhesion test for 50% modulus (N/mm 2 ). bottom.
・ Evaluation criteria for tensile properties The evaluation criteria for tensile properties are that the 50% modulus is 0.15 N/mm ² or more, the maximum tensile stress is 0.38 N/mm ² or more, and the elongation rate at the maximum load is When it was 650% or less, the tensile properties of the sealant were evaluated as being excellent, and this was indicated as "◯".
The tensile properties of the sealant are better if the 50% modulus is greater than 0.15 N/mm ² , the maximum tensile stress is greater than 0.38 N/mm ² or the elongation at maximum load is less than 650%.
On the other hand, if the 50% modulus is less than 0.15 N/mm ² , if the maximum tensile stress is less than 0.38 N/mm ² , or if the elongation at maximum load is more than 650% , the tensile properties of the sealant were evaluated as poor, and this was indicated as "x".

<Adhesion>
Create a temporary joint surrounded by a backer of D10 mm × W25 mm × H300 mm on the slate plate, apply a primer (Primer No. 40: manufactured by Sika Hamatite Co., Ltd.) on the slate plate in the temporary joint, and apply each Samples (each composition prepared as described above) were applied.
After curing the composition for 7 days at 23 ° C., exterior paint 1 or 2 described later is applied on the composition, and the exterior paint 1 or 2 is applied under standard curing conditions at 23 ° C. The adhesion was measured 7 days and 14 days after the application of No. 2.
In addition, a water resistance test was performed by immersing each sample after 14 days in water at 23° C. for 7 days, and adhesion (water resistance) after the water resistance test was measured.
The adhesiveness measuring method is JIS K5600;1999. 4-6 According to the cross-cut method, a test method of 25 squares formed when 6 grid-like (grid-like) cuts (2 mm intervals) reaching the substrate (slate plate) were made.
・Adhesion evaluation criteria Using exterior paint 1, after 7 days of standard curing, after 14 days of standard curing, and in tests according to the cross-cut method after water resistance test, the number of sheets adhered to the slate plate was 25 squares. When the number of sheets was 10 or more, the adhesion of the exterior paint 1 to the paint was evaluated as excellent, and this was indicated as "◯". The same applies to the exterior paint 2 as well.
Using Exterior Paint 1, from the application of Exterior Paint 1, 7 days after standard curing, 14 days after standard curing, and after a water resistance test according to the cross-cut method, any of the tests according to the cross-cut method Number of sheets adhered to the slate plate. When there were 9 or less out of 25 squares, the adhesion of exterior paint 1 to the paint was evaluated as poor, and this was indicated as "x". The same applies to the exterior paint 2 as well.
Then, when both of the above judgments regarding the adhesion of the exterior paints 1 and 2 were "O", it was evaluated that the adhesion to the paint was excellent in the present invention.
On the other hand, in the present invention, when at least one of the above judgments regarding the adhesion of the exterior paints 1 and 2 was "x", the adhesion to the paint was evaluated as poor.

(Exterior coating material 1) Exterior finishing paint manufactured by SK Kaken Co., Ltd. Exterior coating material 1 has an undercoat material: water-based Miraxealer Eco Clear (epoxy-based undercoat material) and a topcoat material: water-based ceramic silicon.
After curing for 7 days at 23° C., the undercoat material of exterior coating material 1 was applied on top of the composition, and the topcoat material of exterior coating material 1 was applied on the undercoat material.
(Exterior coating material 2) Exterior coating material manufactured by Nippon Paint Co., Ltd. The exterior coating material 2 has an undercoat material: water-based cationic sealer (epoxy-based undercoat material) and a topcoat material: Oudefresh Si100III.
After curing the composition for 7 days at 23 ° C., the exterior coating material 2 is applied on top of the composition, and the exterior coating material 2 is applied over the undercoat material. After that, the above standard curing etc. were performed.

<Hot and cold repetition test>
Create a temporary joint surrounded by a backer of D10 mm × W25 mm × H300 mm on the slate plate, apply a primer (Primer No. 40: manufactured by Sika Hamatite Co., Ltd.) on the slate plate in the temporary joint, and apply each Samples (each composition prepared as described above) were applied.
After curing each composition for 7 days under 23 ° C. conditions, exterior paint 1 or 2 described later is applied on the composition and standard curing (7 days under 23 ° C. conditions), JIS According to A 6909:2014 Architectural Finishing Coating Material "7.11 Hot and Cold Repeat Test", a hot and cold repeat test was carried out under the following conditions.
(Conditions for hot and cold repeated test)
As for the heating and cooling conditions, one cycle consists of (1) immersion at +23° C.±2° C./18 hours→(2) cooling at −20° C./3 hours→(3) heating at +50° C.±3° C./2 hours.
The above (1) to (3) are repeated for 10 cycles.
The state of the coating film of the exterior paint after the repeated heating and cooling test was visually confirmed.
・Evaluation criteria for hot and cold repeated test Using exterior paint 1 or 2, the state of the coating film of the exterior paint after the hot and cold repeated test is the state of the coating film of the exterior paint before the hot and cold repeated test (the coating film is uniform ) and no abnormalities were observed (that is, the appearance judgment after 10 cycles of exterior paints 1 and 2 were both “O”), the coating film of the sealant and the paint (of It was evaluated that the durability of adhesion to the coating film was excellent. The excellent adhesion durability means that the difference in linear expansion coefficient between the sealing material and the coating material (coating film) is small and/or the specific polyepoxy compound is difficult to migrate to the coating material (coating film). Conceivable.
On the other hand, exterior paint 1 or 2 was used, and the state of the coating film of the exterior paint before the repeated hot water cooling test was uniform, but after the repeated hot and cold test, the coating film of either exterior paint 1 or 2 When there was blistering or peeling (that is, at least one of the external appearance judgments after 10 cycles of exterior paints 1 and 2 was "x"), the durability was evaluated as poor.

<Stain resistance>
Create a temporary joint (length 150 mm × width 25 mm × height 10 mm) surrounded by a backer on the slate plate, apply a primer (Primer No. 40: manufactured by Sika Hamatite Co., Ltd.) on the slate plate in the temporary joint, and apply the above Each composition prepared as described above was applied over the primer.
After curing each composition for 7 days under 23 ° C. conditions, apply the exterior paint 1 or 2 above on each composition, and after standard curing (7 days under 23 ° C. conditions), Accelerated treatment was carried out at 80° C. for 7 days. After that, return to room temperature for 1 day under the condition of +23 ° C, sprinkle volcanic ash on the surface of the obtained sample (on the exterior paint) without gaps, tap the sample, and the area ratio (%) of volcanic ash adhering to the sample. was measured.
・ Evaluation criteria for stain resistance Using exterior paint 1 or 2, the area ratio of volcanic ash adhered to the surface area of the sample in the backer (length 150 mm × width 25 mm) was less than 5% (that is, , both exterior paints 1 and 2 were evaluated as having excellent contamination resistance.
On the other hand, exterior paint 1 or 2 was used, and any of the above area ratios was 5% or more (that is, at least one of the determinations of the volcanic ash adhesion rate % of exterior paints 1 and 2 was "x". ), the stain resistance of the paint was evaluated as poor.

Table 3 shows the details of each component shown in the column "Curing agent component 2" in Table 2.

4a. Epoxidized linseed oil-based compounds include compounds represented by the following structures.

4b. Epoxidized soybean oil-based compounds include compounds represented by the following structures.

4c. Alicyclic epoxy resin compounds include compounds represented by the following structures.

Diisonyl phthalate is a compound represented by the following structure.

Fatty acid 2-ethylhexyl (one epoxy group) is a compound represented by the following structure. The fatty acid 2-ethylhexyl has one epoxy group.

Epoxidized α-olefin oxide 2 (Eposizer M-24) is a compound represented by the following structure.

Di-2-ethylhexyl 4,5-epoxycyclohexane-1,2-dicarboxylate is a compound represented by the following structure.

From the results shown in Table 2, Comparative Examples 1 to 3, in which the content of the specific polyepoxy compound in the composition was less than 2% by mass, exhibited poor adhesion to paint.
Comparative Example 4, which does not contain a specific polyepoxy compound and instead contains a plasticizer (DINP) that does not have an epoxy group, exhibits adhesion to paint, stain resistance of paint, and adhesion between the coating film of the sealant and the paint. Adhesion durability was poor.
Comparative Examples 5 to 7 and 11 to 13, which did not contain a specific polyepoxy compound and instead contained a compound having one epoxy group, exhibited poor adhesion to at least paint.
Comparative Examples 9 and 10, which do not contain a specific polyepoxy compound and instead contain a compound having one epoxy group at the end, show tensile properties, adhesion to paint, and durability of adhesion between the coating film of the sealant and the paint. was nasty.
Comparative Example 8, which does not contain a specific polyepoxy compound and contains an increased amount of polyoxyalkylene in which all the terminal OH groups are blocked with acetic acid compared to Comparative Example 1, has excellent adhesion to paint and sealant coating film. Durability of adhesion with paint was poor.
Comparative Example 14, which does not contain a specific polyepoxy compound and instead contains a bisphenol A type epoxy resin having an ether bond in addition to the epoxy group, exhibits tensile properties, adhesion to paint, stain resistance of paint, and sealing material. The adhesion durability between the paint film and the paint was poor.

In contrast, the composition of the present invention, when used as a sealant, was excellent in tensile properties, adhesion to paint, and stain resistance of paint. In addition, the composition of the present invention was excellent in the durability of adhesion between the paint film of the sealant and the paint.

Claims (7)

a base containing a urethane prepolymer having an isocyanate group;
A curing agent containing a polyol and a polyepoxy compound having a plurality of epoxy groups in one molecule and an epoxy equivalent of 100 to 200 g/eq,
The content of the polyepoxy compound is 2.0 to 15.0% by mass in the composition,
A two-component polyurethane sealant composition, wherein each of said epoxy groups is independently bonded to a hydrocarbon group, and said hydrocarbon group does not have an ether bond. The two-component polyurethane according to claim 1, wherein the polyepoxy compound comprises at least one selected from the group consisting of epoxidized linseed oil-based compounds, epoxidized soybean oil-based compounds, and alicyclic epoxy resin compounds. Sealant composition. 3. A two-component polyurethane sealant composition according to claim 1 or 2, wherein the polyepoxy compound comprises an epoxidized linseed oil-based compound and/or a cycloaliphatic epoxy resin compound. A two-component polyurethane sealant composition according to claim 1 or 2, wherein said polyepoxy compound comprises a polyepoxy compound having an epoxy equivalent of 120-170 g/eq. A two-component polyurethane sealant composition according to claim 1 or 2, wherein said polyepoxy compound comprises a polyepoxy compound having an epoxy equivalent of 140-170 g/eq. 3. A two-component polyurethane sealant composition according to claim 1 or 2, wherein said curing agent further comprises a terminally esterified polyether. 7. The two-component polyurethane sealant composition according to claim 6, wherein the content of said terminal esterified polyether is 2.0 to 5.0% by mass in said composition.