JP7628520B2 - Moisture-curable composition for forming a cured product for applying a topcoat layer to a surface - Google Patents

Description

The present invention relates to a cured product obtained by curing a moisture-curable composition containing a silane-modified polymer having a terminal silyl group that can be crosslinked by hydrolysis, represented by --CH ₂ --SiR ¹ _a (OR ² ) _3-a , and a specific aminosilane; a laminate comprising a substrate, the cured product, and a topcoat layer; a method for bonding the cured product and the topcoat layer; and a method for producing the laminate.

Known types of sealing materials include silicone-based sealing materials, modified silicone-based sealing materials, and polyurethane-based sealing materials.
Silicone-based sealants, which contain silicone (organopolysiloxane) as a main component, generally have low paint compatibility with their surfaces, and it is difficult to form a topcoat layer on the surface of the silicone-based sealant.
On the other hand, modified silicone sealants, which are mainly composed of polyethers with silyl groups at the ends, have higher paint compatibility than silicone sealants, and are often easy to form a topcoat layer on the sealant surface, making them industrially useful. In particular, polymers with reactive silicon groups (reactive silicon-containing functional groups that can form siloxane bonds and crosslink by hydrolysis and condensation reactions) and oxyalkylene main chains are liquid at room temperature, and the cured products have low modulus and high elongation properties, so they are used in sealants, adhesives, various coating materials, etc.

A moisture-curable modified silicone (polyoxyalkylene polymer) sealant having reactive silicon groups at its terminals is disclosed, for example, in Patent Document 1. This sealant contains a specific epoxy plasticizer and an antioxidant, and thus maintains adhesion between the cured product and the paint (top coat) even when cured by heating.
In order to further improve the adhesion between a sealant containing a polyoxyalkylene polymer and a top coat, an adhesion promoter based on an aminosilane or a combination of such an aminosilane and an epoxysilane is generally used.
Well-known moisture-curing modified silicones with reactive silicon groups at the ends include those with one methylene group ( _-CH2- ) directly bonded to the reactive silicon group, and those with three methylene groups bonded to the reactive silicon group. Those with one methylene group bonded to them are particularly useful because they can be cured without the use of catalysts containing harmful tin.

Patent No. 6527599 specification

However, it has been found that some moisture-curing polyoxyalkylene polymer sealants having reactive silicon groups at their terminals have low adhesion to a top coat layer.
Specifically, when a moisture-curable composition containing a polyoxyalkylene polymer having one methylene group (-CH ₂ -) directly bonded to an alkoxysilane terminal group, represented by -CH ₂ -SiR ¹ _a (OR ² ) _{3-a ,} ^is used as a sealant, the adhesion of a top coat layer such as a solvent-based acrylic _urethane may be _low . Thus, there has been a ^demand for a method for producing a laminate having excellent adhesion between a top coat layer and a cured product of a moisture-curable composition containing a polyoxyalkylene polymer having an alkoxysilane terminal group, represented by -CH 2 -SiR 1 a (OR 2 ) 3-a.

The present invention has been made in consideration of the above circumstances, and aims to provide a moisture-curable composition for forming a cured product that has good adhesion to a topcoat layer even when a polyoxyalkylene polymer having the above-mentioned terminal group is used, a method for bonding a cured product obtained by curing the moisture-curable composition to a topcoat layer, and a laminate including a substrate, the cured product, and a topcoat layer, and a method for producing the same.

As a result of extensive research, the inventors have discovered that the use ^of an aminosilane having two or more amino groups and one or more ethoxy groups as an adhesion promoter improves the adhesion between a topcoat layer and a cured product obtained by curing a moisture-curable composition containing a polyoxyalkylene polymer having an alkoxysilane terminal group represented by -CH ₂ -SiR ¹ _a (OR 2 ) 3- _a , and have thus completed the present invention.

That is, the present invention provides
A moisture-curable composition for forming a cured product for applying a topcoat layer to a surface, comprising:
(A) a compound represented by the following general formula (1):
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2.
and a silane-modified polymer A of
(B) an aminosilane B having two or more amino groups and one or more alkoxy groups having two or more carbon atoms;
The moisture-curable composition comprises:

The present invention also relates to a laminate comprising a substrate, a cured product obtained by curing the moisture-curable composition, and a topcoat layer laminated on the cured product.

When an aminosilane having a _{methoxy group} , an aminosilane containing ^one amino group, or an aminosilane containing ^one ethoxy group and one amino group is added as an adhesion _improver to a moisture-curable composition containing a polyoxyalkylene polymer (silane-modified polymer A) having an alkoxysilane terminal group represented by --CH 2 --SiR 1 a (OR 2 ) 3-a, the surface of the cured product obtained by curing the crosslinked composition has poor paintability, and even if a topcoat layer is applied to the cured product, it is prone to peeling off.
However, the paintability is improved only when an aminosilane having two or more amino groups and one or more alkoxy groups having two or more carbon atoms is added as an adhesion promoter, and when a topcoat layer is applied to the surface of the cured product, the effect of good adhesion to the topcoat layer can be obtained.
In addition, a laminate including a cured product obtained by curing the moisture-curable composition of the present invention and a topcoat layer has the property that the adhesion between the cured product and the topcoat layer is high and the topcoat layer is not easily peeled off.

The adhesion method of the present invention is a method for adhering a cured product obtained by curing a moisture-curable composition containing a silane-modified polymer A represented by the following general formula (1) to a top coat layer, and is characterized in that an aminosilane B having two or more amino groups and one or more alkoxy groups having two or more carbon atoms is blended with the moisture-curable composition.
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2.

A moisture-curable composition containing a polyoxyalkylene polymer (silane-modified polymer A) having an alkoxysilane terminal group represented by --CH ₂ --SiR ¹ _a (OR ² ) _3-a and an aminosilane having a trimethoxy group, an aminosilane containing one amino group, or an aminosilane containing one ethoxy group and one amino group, which are commonly used aminosilane-based adhesion improvers, is cured, and even if a topcoat layer is applied to the surface of the cured product, the adhesion is poor and the topcoat layer is easily peeled off.
Here, by using an aminosilane having two or more amino groups and one or more alkoxy groups having two or more carbon atoms as the adhesion improver, it is possible to improve the adhesion of the topcoat layer to the surface of the cured product.

The method for producing a laminate of the present invention is a method for producing a laminate by bonding a cured product formed on a substrate and obtained by curing a moisture-curable composition to a top coat layer, the method comprising the steps of:
The moisture-curable composition is
(A) a compound represented by the following general formula (1):
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2.
and a silane-modified polymer A of
(B) an aminosilane B having two or more amino groups and one or more alkoxy groups having two or more carbon atoms,

The above manufacturing method produces a laminate in which the cured product and the topcoat layer are firmly bonded.

The present invention is described in detail below.

The moisture-curable composition of the present invention may be in any form or shape as long as it is in the form of at least one liquid and can be cured by moisture to finally obtain a cured product of the composition. The polyoxyalkylene polymer (silane-modified polymer A) contained in the moisture-curable composition and having an alkoxysilane terminal group represented by -CH ₂ -SiR ¹ _a (OR ² ) _3-a generates silanols by hydrolysis due to moisture. A matrix of siloxane bonds is formed by a dehydration condensation reaction between these silanols, and the composition is cured.

<Silane-modified polymer A>
The silane-modified polymer A in the present invention contains at least one alkoxysilyl group of the following general formula (1). This may be an alkoxysilyl group linked to one end of the polymer backbone. Preferably, it is a silane-modified polymer containing at least one polyoxyalkylene structural unit.
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2.

The silane-modified polymer A is not particularly limited as long as it is an organic polymer, and may be, for example, a polyoxypropylene polymer, a polyoxybutylene polymer, a polyisobutylene polymer, a (meth)acrylic acid ester polymer, or an organic polymer using a plurality of these polymers.

At least one of the terminal groups of the silane-modified polymer A may be a group represented by the following general formula (2) or (3).
-OC(=O)-NH-(CH ₂ )-SiR ¹ _a (OR ² ) _3-a (2)
-NH-C(=O)-NR'-(CH ₂ )-SiR ¹ _a (OR ² ) _3-a (3)
In formula (2) and formula (3), the groups and subscripts have one of the definitions specified above.
R' is a monovalent, optionally substituted, SiC-bonded hydrocarbon radical.

The silane-modified polymer A is the main component of the moisture-curable composition, and is a component that forms a cured product by the action of moisture after application.
The silane-modified polymer A can be purchased as a commercial product or can be prepared by a common chemical method. The silane-modified polymer A may be a single polymer or a mixture of two or more kinds.
The silane-modified polymer A may be a so-called α-silane-terminated polymer having reactive alkoxysilyl groups linked to adjacent urethane units via methylene spacers. The silane-modified polymer A having such a structure achieves a high cure rate when in contact with air, and is therefore safer and less environmentally hazardous in that no toxic tin catalysts are required. Commercially available α-silane-terminated polymers are GENIOSIL® STP-E10 or STP-E30 from Wacker-Chemie AG.

The group R ¹ is a monovalent, optionally substituted, SiC-bonded hydrocarbon group.

Examples of radicals R ¹ are alkyl radicals, such as methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl radicals; hexyl radicals, such as the n-hexyl radical; heptyl radicals, such as the n-heptyl radical; octyl radicals, such as the n-octyl radical, the isooctyl radical and the 2,2,4-trimethylpentyl radical; nonyl radicals, such as the n-nonyl radical; decyl radicals, such as the n-decyl radical; dodecyl radicals, such as the n-dodecyl radical. cycloalkyl groups, such as cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl; alkenyl groups, such as vinyl, 1-propenyl and 2-propenyl; aryl groups, such as phenyl, naphthyl, anthryl and phenanthryl; alkaryl groups, such as o-, m-, p-tolyl, xylyl and ethylphenyl, and aralkyl groups, such as benzyl, α- and β-phenylethyl.

Examples of substituted groups R ¹ are haloalkyl groups, such as the 3,3,3-trifluoro-n-propyl, 2,2,2,2',2',2'-hexafluoroisopropyl and heptafluoroisopropyl groups, and haloaryl groups, such as the o-, m- and p-chlorophenyl groups.

Preferably, ^R1 comprises a monovalent hydrocarbon group, preferably optionally substituted by halogen atoms, having from 1 to 6 carbon atoms, more preferably an alkyl group having 1 or 2 carbon atoms, and more particularly a methyl group.

Examples of radicals ^R2 are those specified for radical ^R1 .
The group ^R2 is preferably a hydrogen atom or an alkyl group, optionally substituted by a halogen atom, having from 1 to 10 carbon atoms, more preferably having from 1 to 4 carbon atoms, and more particularly a methyl and ethyl group.

It should be understood that the polymer on which the polymer group Y is based in the present invention is any polymer in which at least 50%, preferably at least 70%, and more preferably at least 90% of the total bonds in the backbone are carbon-carbon, carbon-nitrogen, or carbon-oxygen bonds.

The polymer group Y preferably comprises an organic polymer group, which may comprise as the polymer chain polyoxyalkylenes, such as polyoxyethylene, polyoxypropylene, polyoxybutylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymers and polyoxypropylene-polyoxybutylene copolymers; hydrocarbon polymers, such as polyisobutylene, polyethylene, or polypropylene and copolymers of polyisobutylene with isoprene; polyisoprene; polyurethanes; polyesters, polyamides; polyacrylates; polymers such as ethylene glycol; and polycarbonates, which preferably include one or more groups -[-CH]- which are linked by -O-C(=O)-NH-, -NH-C(=O)O-, -NH-C(=O)-NH-, -NR'-C(=O)-NH-, NH-C(=O)-NR'-, -NHC(=O)-, -C(=O)-NH-, -C(=O)-O-, -O-C(=O)-, -O-C(=O)-O-, -S-C(=O)-NH-, -NH-C(=O)-S-, -C(=O)-S-, -S-C(=O)-, -S-C(=O)-S-, -C(=O)-, -S-, -O- and -NR'-. ₂ -SiR ¹ _a (OR ² ) _3-a ].

Here, R' may be the same or different and is an alkyl group, for example, methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl; a hexyl group, for example, n-hexyl; a heptyl group, for example, n-heptyl; an octyl group, for example, n-octyl, isooctyl, and 2,2,4-trimethylpentyl; a nonyl group, for example, n-nonyl; a decyl group, for example, n-decyl; a dodecyl group, for example, cycloalkyl groups, such as cyclopentyl, cyclohexyl, cycloheptyl, and methylcyclohexyl groups; alkenyl groups, such as vinyl, 1-propenyl, and 2-propenyl groups; aryl groups, such as phenyl, naphthyl, anthryl, and phenanthryl groups; alkaryl groups, such as o-, m-, and p-tolyl groups, xylyl, and ethylphenyl groups, and aralkyl groups, such as benzyl, α-, and β-phenylethyl groups.

Examples of substituted groups R' are haloalkyl groups such as 3,3,3-trifluoro-n-propyl, 2,2,2,2',2',2'-hexafluoroisopropyl and heptafluoroisopropyl groups, and haloaryl groups such as o-, m- and p-chlorophenyl groups.
The group R' preferably comprises a monovalent hydrocarbon group optionally substituted by halogen atoms and having from 1 to 6 carbon atoms, more preferably an alkyl group having 1 or 2 carbon atoms, and more particularly a methyl group.

The group R' may be -CH(COOR'')-CH ₂ -COOR'', where R'' may be the same or different and has the definition given for R'.

The group R" is preferably an alkyl group having from 1 to 10 carbon atoms, more preferably a methyl group, an ethyl group, or a propyl group.

More preferably, group Y in formula (1) contains a methacrylate group, a urethane group, and a polyoxyalkylene group, more preferably a polyoxypropylene-containing urethane group or a polyoxypropylene group.

The silane-modified polymer A here can have the groups --[(CH 2 )--SiR 1 a (OR ₂ ) ³ _-a ] attached in the described manner at any desired position in the polymer ^, for example in the chain and/or at the end, preferably in the _chain and at the end, more preferably at the end.

In one particularly preferred embodiment of the present invention, the silane-modified polymer A comprises silane-terminated polyethers and polyurethanes, more particularly silane-terminated polypropylene glycols and polyurethanes, having in each case dimethoxymethylsilyl end groups bonded by an -O-C(=O)-NH-(CR ¹ ₂ ) or -NH-C(=O)-NR'-(CR ¹ ₂ ) group, where R' and R ¹ have one of the definitions specified above.

The number average molecular weight Mn of the silane-modified polymer A is preferably at least 400, more preferably at least 600, more particularly at least 800, and is preferably less than 30,000, more preferably less than 19,000.

The viscosity of the silane-modified polymer A, in each case measured at 20°C, is preferably at least 0.2 Pa·s, more preferably at least 1 Pa·s, very preferably at least 5 Pa·s, and preferably not more than 1,000 Pa·s, more preferably not more than 700 Pa·s.

In the case of a first particularly preferred embodiment of the present invention, the silane-modified polymer A comprises as polymeric group Y linear or branched polyoxyalkylene groups, more preferably polyoxypropylene groups, whose chain ends are bonded, preferably by -O-C(=O)-NH-, to one or more groups -[(CH ₂ )-SiR ¹ _a (OR ² ) _3-a ], where preferably at least 85%, more preferably at least 90%, more particularly at least 95% of all chain ends are bonded by -O-C(=O)-NH- to the group -[(CH ₂ )-SiR ¹ _a (OR ² ) _3-a ].
The polyoxyalkylene group Y has an Mn (number average molecular weight) of 200 to 30,000, preferably 1,000 to 20,000. Suitable processes for preparing such silane-modified polymers (A) and examples of silane-modified polymers (A) themselves are also known and described in publications, including EP 1535940 B1 or EP 1896523 B1, which are incorporated herein by reference. Corresponding silane-terminated polymers are also commercially available, for example, under the name GENIOSIL® STP-E from Wacker Chemie AG.

When the silane-modified polymer A is chemically synthesized, it can be synthesized by various known preparation methods, such as, for example, hydrosilylation, addition reactions such as Michael addition, Diels-Alder addition, or reactions between isocyanate-functional compounds and compounds containing isocyanate-reactive groups.

The content of silane-modified polymer A in the entire composition is not particularly limited, and is preferably in the range of, for example, 5 to 90 parts by mass. If it is 5 parts by mass or more, components other than the components that form the polymer matrix will not remain in the composition in large quantities, the composition will exhibit sufficient performance, the amount of the formed polymer matrix will be sufficient, the required mechanical properties such as tensile strength, elongation, and tear strength will be sufficient, there will be few defects in the cured product such as poor adhesion and cracking of the film, and there will be a low possibility of adverse effects caused by other components. More preferably, it is in the range of 10 to 60 parts by mass.

<About Aminosilane B>
Aminosilane B is an adhesion promoter having two or more amino groups and one or more alkoxy groups having two or more carbon atoms, and may also function as a curing catalyst.
Aminosilane B may have a structure represented by the following general formula (4).
D _h Si (O R ⁷ ) _g R ⁶ _f O _{(4 - f - g - h) / 2} (4)
(Wherein,
^R6 is a monovalent, optionally substituted, SiC-bonded, nitrogen-free hydrocarbon group, which may be the same or different;
R ⁷ may be the same or different and is an optionally substituted hydrocarbon group having 2 to 18 carbon atoms;
D are identical or different and represent monovalent SiC-bonded groups having at least one nitrogen atom, the number of nitrogen atoms contained in one or more Ds is 2 or more, f is 0, 1, 2 or 3, preferably 0 or 1,
g is 1, 2 or 3, preferably 2 or 3;
h is 1, 2, or 3, preferably 1;
However, the sum of f + g + h is 4 or less.)

The aminosilane B used in the present invention may be either a silane (i.e., a compound of formula (4) where f + g + h = 4) or a siloxane (i.e., a compound of formula (4) where f + g + h ≦ 3), with silane being preferred.

The radical R ⁶ preferably represents an optionally halogen-substituted hydrocarbon radical having 1 to 18 carbon atoms, particularly preferably a hydrocarbon radical having 1 to 5 carbon atoms, in particular methyl.

The radical R ⁷ is preferably an optionally halogen-substituted hydrocarbon radical having 2 to 18 carbon atoms, particularly preferably a hydrocarbon radical containing 2 to 10 carbon atoms, in particular the ethyl radical.

Examples of radicals D are the formulas H ₂ N(CH ₂ ) ₃ -, H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₃ -, H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₂ NH(CH ₂ ) ₃ -, H ₃ CNH(CH ₂ ) ₃ -, C _2H5NH ( _CH2 ) _3- , _{C3H7NH ( CH2 ) 3- , C4H9NH} ( _CH2 ) _{3- , C5H11NH} (CH2 _{) 3- , C6H13NH} ( _CH2 ) _3- , _{C7H 15} NH(CH ₂ ) ₃ -, H ₂ N(CH ₂ ) ₄ --, H ₂ N-CH ₂ --CH(CH ₃ )-CH ₂ --, H ₂ N(CH ₂ ) ₅ --, cyclo-C ₅ H ₉ NH(CH ₂ ) ₃ --, cyclo-C ₆ H ₁₁ NH(CH ₂ ) ₃ --, phenyl-NH(CH ₂ ) ₃ --, (CH ₃ ) ₂ N(CH ₂ ) ₃ --, (C ₂ H ₅ ) ₂ N(CH ₂ ) ₃ --, (C ₃ H ₇ ) ₂ N(CH ₂ ) ₃ --, (C ₄ H ₉ ) ₂ N(CH ₂ ) ₃ --, (C ₅ H ₁₁ ) ₂ N(CH ₂ ) ₃ --, (C ₆ H ₁₃ ) ₂ N(CH ₂ ) ₃ -, (C ₇ H ₁₅ ) ₂ N(CH ₂ ) ₃ -, H ₂ N(CH ₂ )-, H ₂ N(CH ₂ ) ₂ NH(CH ₂ )-, H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₂ NH(CH ₂ )-, H ₃ CNH(CH ₂ )-, C ₂ H ₅ NH(CH ₂ )-, C ₃ H ₇ NH(CH ₂ )-, C ₄ H ₉ NH(CH ₂ )-, C ₅ H ₁₁ NH(CH ₂ )-, C ₆ H ₁₃ NH(CH ₂ )-, C ₇ H ₁₅ NH(CH ₂ )-, cyclo-C ₅ H ₉ NH(CH ₂ )-, cyclo-C ₆ H ₁₁ NH(CH ₂ )-, phenyl-NH(CH ₂ )-, (CH ₃ ) ₂ N(CH ₂ )-, (C ₂ H ₅ ) ₂ N(CH ₂ )-, (C ₃ H ₇ ) ₂ N(CH ₂ )-, (C ₄ H ₉ ) ₂ N(CH ₂ )-, (C ₅ H ₁₁ ) ₂ N(CH ₂ )-, (C ₆ H ₁₃ ) ₂ N(CH ₂ )-, (C ₇ H ₁₅ ) ₂ N(CH ₂ )-, and the reaction products of the abovementioned primary amino groups with compounds containing double bonds or epoxy groups reactive towards primary amino groups.

The group D is preferably H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₃ -- or H ₂ N(CH ₂ ) ₂ NH(CH ₂ )--.

Examples of silanes (4) which may be used according to the invention are H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₃ -Si(OC ₂ H ₅ ) ₃ , H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₃ -Si(OC ₂ H ₅ ) ₂ CH ₃ , H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₂ NH(CH ₂ ) ₃ -Si(OC ₂ H ₅ ) ₃ and their partial hydrolysates, such as H ₂ N(CH ₂ ) ₂ NH(CH ₂ ) ₃ -Si(OC ₂ H ₅ ) 3 , H ₂ N(CH ₂ ) 2 NH(CH ₂ ) ₃ -Si(OC ₂ H ₅ ) ₃ . _2CH3 or in each case their partial _hydrolysates .

The aminosilane B in the present invention is not limited to the aminosilane monomer of formula (4) above or a hydrolyzate thereof, but may also be an amino-modified silicone that exerts its effect through a similar mechanism.

The aminosilanes B of the invention may act as adhesion promoters and/or water scavengers in the moisture-curable compositions of the invention and may also function as curing catalysts or cocatalysts.
The aminosilanes B used according to the invention are commercial products and can be prepared by methods commonly used in chemistry.

The content of aminosilane B in the entire composition is not particularly limited, and is preferably in the range of 0.1 to 10 parts by mass, for example. If it is 0.1 part by mass or more, it is possible to promote the hydrolysis and condensation reaction of the silane-modified polymer. On the other hand, if it is less than 0.1 part by mass, the effect of catalyzing the hydrolysis and condensation reaction decreases, and the adhesiveness also decreases. Furthermore, if it is 10 parts by mass or more, the hydrolysis and condensation reaction may progress during storage of the moisture-curable composition, and the storage stability may deteriorate, such as gelling and hardening during storage. A range of 0.5 to 5 parts by mass is more preferable.

The hydrolysis rate of aminosilanes having alkoxy groups with 2 or more carbon atoms, including ethoxy groups, is slower than the hydrolysis rate of silane-modified polymer A having an alkoxysilane terminal group represented by -CH ₂ -SiR ¹ _a (OR ² ) _3-a . For this reason, when moisture (for example, moisture in the air or moisture derived from the substrate to which the moisture-curable composition is applied) is supplied to a moisture-curable composition containing silane-modified polymer A and aminosilane B, the alkoxy groups of the silane-modified polymer A are first hydrolyzed to generate silanol groups, and a matrix is formed and cured by a dehydration condensation reaction between these silanol groups. Thereafter, aminosilane B, which was not incorporated into the matrix of silane-modified polymer A due to its slow reaction rate, migrates to the surface of the cured product over time. Then, the amino groups derived from aminosilane B are oriented near the surface of the cured product, and interact with the topcoat layer applied to the surface, improving the adhesion between the cured product and the topcoat layer. The more amino groups derived from aminosilane B exposed on the surface of the cured product, the more improved the adhesion. For this reason, it is preferable that aminosilane B has two or more amino groups. Although aminosilane B has a slower hydrolysis rate than silane-modified polymer A, it generates silanol groups by hydrolysis in the same way as silane-modified polymer A, and these silanol groups are finally incorporated into the matrix of silane-modified polymer A through a condensation reaction between these silanol groups and the remaining silanol groups of silane-modified polymer A, which is thought to improve the adhesion durability between the cured product and the topcoat layer.

In many cured products obtained from moisture-curable compositions containing silane-modified polymers, the adhesion to the topcoat layer was generally considered to be good. This is presumably due to the fact that in a system in which a silane-modified polymer is hydrolyzed and dehydrated and condensed using a tin catalyst (usually a polymer having an alkoxysilane terminal group represented by -(CH ₂ ) ₃ -SiR ¹ _a (OR ² ) _3-a ), the reaction rate was sufficiently fast compared to various aminosilanes. A matrix was formed first by dehydration and condensation between the silanol groups of the hydrolyzed silane-modified polymer, and the aminosilane, regardless of its type (particularly the type of alkoxy group), was exposed to the surface of the cured product and was able to exert the effect of improving the adhesion to the topcoat layer.

However, it is presumed that the polyoxyalkylene polymer (silane-modified polymer A) having an alkoxysilane terminal group represented by -CH ₂ -SiR ¹ _a (OR ² ) _3-a has a relatively slower reaction rate than other silane-modified polymers that undergo hydrolysis and dehydration condensation reactions with a tin catalyst, and has a reaction rate comparable to that of many aminosilane-based adhesion improvers (aminosilanes having a methoxy group and a relatively fast hydrolysis rate), which has caused a problem specific to silane-modified polymer A, namely, poor adhesion. In the case of moisture-curable compositions containing these aminosilane-based adhesion improvers, silane-modified polymer A cures in a state in which the aminosilane is incorporated into the silane-modified polymer A matrix before migrating to the silane-modified polymer A surface. This means that the aminosilane cannot migrate to the surface of the cured product, and the effect of improving adhesion cannot be exerted.

<Topcoat layer>
The topcoat layer is applied as a paint onto the top (surface) of the cured product for the purpose of imparting, for example, weather resistance, light resistance, water resistance, and stain resistance to the coating layer.
The type of the topcoat layer is not particularly limited, and may be, for example, a synthetic resin paint such as an acrylic resin, an acrylic urethane resin, an acrylic silicone resin, a urethane resin, a fluororesin, an alkyd resin, an amino resin, an unsaturated polyester resin, an epoxy resin, a vinyl butyral resin, or a vinyl chloride resin, or an oil-based paint mainly composed of boiled oil, drying oil, or oil varnish, or a cellulose paint mainly composed of nitrocellulose (nitrocellulose), etc. These topcoats may be, for example, a strong solvent type, a weak solvent type, or a water-based type.
It is believed that the adhesion between the silane-modified polymer cured product and the acrylic urethane top coat layer is improved by forming a urea bond through the reaction between the isocyanate group of the acrylic urethane and the amino group of the aminosilane. The intermolecular force between the aminosilane and the acrylic urethane is also believed to be a factor in improving the adhesion.

Examples of additives for the composition for the top coat layer include an ultraviolet absorbing agent, a light stabilizer, a light shielding agent, a film-forming assistant, a stain-resistant hydrophilicity imparting agent, etc. In order to match the color tone of the repaired portion, a pigment can be mixed into the coating liquid of the composition for the top coat layer.
As the light-shielding material, calcium carbonate, silica, alumina, magnesium oxide, talc, clay, etc. can be used.
As the film-forming aid, Texanol, butyl cellosolve, butyl cellosolve acetate, carbitol, triethylene glycol, etc. can be used.
As a hydrophilicity imparting material for the purpose of stain resistance, organosilicate, fluorine-based surfactant, photocatalytic titanium oxide, etc. can be used.
As the solvent, an aliphatic hydrocarbon compound such as mineral spirits can be used.

<Other raw materials contained in the moisture-curing composition>
When the moisture-curable composition containing the above-mentioned silane-modified polymer A and aminosilane B is used as a sealant for various substrates in various applications, the form and composition contents are not limited.
As a composition for a typical application, which is a sealing material suitable for substrates such as building materials and industrial structures, and which is used to apply a topcoat layer to the surface of the cured product, the following composition is preferred.
Silane-modified polymer A: 5 to 90 parts by mass Aminosilane B: 0.1 to 10 parts by mass Thixotropic adjuster C: 0 to 20 parts by mass Plasticizer D: 0 to 50 parts by mass Dehydrating agent E: 0 to 10 parts by mass Stabilizer F: 0.01 to 5 parts by mass Filler G: 0 to 80 parts by mass Curing catalyst H: 0 to 5 parts by mass However, the parts by mass of each component are based on 100 parts by mass of the entire moisture-curable composition.

The thixotropic regulator C, which is optionally added, imparts a certain level of thixotropy to the moisture-curable composition of the present invention by forming a network within the system through van der Waals forces and thickening the entire system.

Inorganic particles used as a raw material for thixotropic regulator C include, for example, inorganic particles such as silica, titanium dioxide, bentonite, zinc oxide, talc, kaolin, mica, vermiculite, magnesium carbonate, calcium carbonate, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, strontium silicate, metal tungstate, magnesium, zeolite, barium sulfate, calcined calcium sulfate, calcium phosphate, fluorapatite, hydroxyapatite, and metal soap. In addition, composite particles obtained by coating particles with metal oxides or the like, and modified particles whose particle surfaces have been treated with compounds or the like may also be used.

Typically, the surfaces of these particles have portions that are covered with hydrophilic groups such as silanol groups, carbinol groups, or other hydroxyl groups, and portions that are covered with groups that have been hydrophobized with alkyl groups or the like, or with other hydrophobic groups.
By adjusting the ratio of the hydrophilic groups to the hydrophobic groups, the coagulation and solubility of the inorganic particles in the system can be controlled.

Among the inorganic particles, it is preferable to use silica. There are various types of silica, such as fumed silica, wet silica, and colloidal silica. However, all types of silica particles have hydrophilic silanols on the surface, and these silanol groups can be hydrophobized with alkyl groups or the like in any ratio, making it easy to set the molar ratio of hydrophilic and hydrophobic groups on the surface. In addition, silica is preferable because it has an aggregated structure, has high affinity with various oils, and is easy to obtain and economical, allowing it to be used in a wide range of applications.

The most preferred silica for this invention is fumed silica.
Fumed silica particles have a multi-aggregated structure, which allows the balance of hydrophilic and hydrophobic groups on the surface to be controlled according to the aggregation level, and the aggregation units to be recombined.
In addition, since the fumed silica particles have a porous structure, the surface area is increased, and the association and adsorption functions are enhanced, so that the system can be generated more stably and uniformly.

The fumed silica particles have a primary particle, which is the smallest unit, usually having a size of about 5 to 30 nanometers, and the primary particles aggregate to form primary aggregates, that is, secondary particles.
The size of the primary aggregates is usually about 100 to 400 nanometers. Since the primary particles are fused together by chemical bonds, it is usually difficult to separate the primary aggregates. Furthermore, the primary aggregates form an aggregate structure, which is called a secondary aggregate, i.e., a tertiary particle. The size of the secondary aggregates is generally about 10 μm. The aggregation form between the primary aggregates in the secondary aggregates is usually due to hydrogen bonds or van der Waals forces, rather than chemical bonds.

In powder form, the secondary aggregates of fumed silica particles are often the largest aggregated state. However, in moisture-curing compositions, the secondary aggregates can further aggregate. In other words, one example of this is when the hydrophobic silica effectively forms a network with the hydrophobic portion of the silane-terminated modified polymer and the reactive material (reactive diluent) by van der Waals forces in the present invention. The force that separates the aggregates can be weaker than the force that separates the secondary aggregates. In other words, one example of this is when the moisture-curing composition of the present invention is applied with a comb trowel or the like, the viscosity during application is reduced by separating the aggregates.

The fumed silica particles are preferably hydrophobized, and the components used for hydrophobization are not particularly limited. The components used for hydrophobization are, for example, halogenated organosilicon such as methyltrichlorosilane, alkoxysilanes such as dimethyldialkoxysilane, silazane, and low molecular weight methylpolysiloxane, and can be hydrophobized by a known method of treatment.

Thixotropic adjuster C, which is optionally added, is, for example, an organic type such as a hydrogenated castor oil type, an amide type, an oxidized polyethylene type, a vegetable oil polymerized oil type, or a surfactant type. Thixotropic adjuster C may be a single component or two or more of these may be used in combination.

The content of thixotropic regulator C in the entire composition does not have to be included, but it is preferable that it is 0.1 to 20 parts by mass. If it exceeds 20 parts by mass, the viscosity of the entire system increases, which may lead to inhomogeneity due to poor stirring during production of the moisture-curing composition and a significant decrease in workability during application. It is more preferable that it is in the range of 1 to 10 parts by mass, and even more preferable that it is in the range of 2 to 5 parts by mass.

Plasticizer D is a component that has the function of adjusting the viscosity and viscosity of the moisture-curable composition of the present invention, and can also act as a physical property adjuster such as tensile strength and elongation, and as an additive that improves the flexibility and weather resistance of the cured product. This component is not essential for the moisture-curable composition of the present invention if the above functions and actions are not required. Plasticizer D can be purchased as a commercial product, or can be prepared by common chemical methods.

Examples of plasticizers D are phthalates, such as dioctyl phthalate, diisooctyl phthalate and diundecyl phthalate; perhydrogenated phthalates, such as diisononyl 1,2-cyclohexanedicarboxylate and dioctyl 1,2-cyclohexanedicarboxylate; adipates, such as dioctyl adipate; benzoates; glycol esters; esters of saturated alkanediols, such as 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate; phosphates; sulfonates; polyesters; polyethers, such as polyethers having a molar mass preferably between 1000 and 10,000 g/mol. polyethylene glycols and polypropylene glycols; polystyrene; polybutadiene; polyisobutylene; paraffinic hydrocarbons; and high molecular weight branched hydrocarbons.

The content of plasticizer D in the entire composition does not have to be included, but it is preferable that it is in the range of 0 to 50 parts by mass. If it exceeds 50 parts by mass, it may cause problems such as deterioration of the physical properties of the coating film, and it may cause poor curing or non-curing after application. It is more preferable that it is in the range of 0 to 30 parts by mass.

The dehydrating agent E is a component that dehydrates the moisture-curable composition of the present invention by trapping water.
The dehydrating agent E can be purchased as a commercial product or can be prepared by common chemical methods.
The dehydrating agent E may be a single agent or a mixture of two or more agents.

Examples of dehydrating agents E are silanes, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, O-methylcarbamatemethyl-methyldimethoxysilane, O-methylcarbamatemethyl-trimethoxysilane, O-ethylcarbamatemethyl-methyldiethoxysilane, O-ethylcarbamatemethyl-triethoxysilane and/or their partial condensates, and also orthoesters, such as 1,1,1-trimethoxyethane, 1,1,1-triethoxyethane, trimethoxymethane and triethoxymethane.

The content of dehydrating agent E in the entire composition does not have to be included, but it is preferable that it is in the range of 0.01 to 10 parts by mass. If it is less than 0.01 part by mass, the dehydrating effect is insufficient and problems such as thickening, gelling, and hardening may occur during production and storage, and if it exceeds 10 parts by mass, it may cause problems such as deterioration of the physical properties of the coating film, and may cause poor hardening or non-hardening after application. A range of 0.5 to 3.0 parts by mass is more preferable.

Stabilizer F is a component that functions as an ultraviolet absorber, antioxidant, heat stabilizer, and light stabilizer for the moisture-curable composition of the present invention, and can also act as a stabilizer against polymer deterioration.
Stabilizer F can be purchased as a commercial product or can be prepared by common chemical methods.
The stabilizer F may be a single substance or a mixture of two or more substances.

Stabilizer F may be any agent that exhibits the above-mentioned functions and effects, but is not limited thereto. Preferably, however, it is an antioxidant, an ultraviolet stabilizer, or a HALS.

The content of stabilizer F in the entire composition is preferably in the range of 0.01 to 5 parts by mass. If it is less than 0.01 part by mass, deterioration of the coating film due to ultraviolet rays, heat, oxidation, etc. may occur, and if it exceeds 5 parts by mass, unexpected problems may occur, such as color changes in transparent products. A range of 0.5 to 2.0 parts by mass is more preferable.

The filler G, which is optionally blended, is a component that has the functions of an extender, viscosity adjuster, and physical property adjuster such as tensile strength and elongation for the moisture-curable composition of the present invention, and can also act as a curing accelerator for the coating material due to the moisture it contains. If the above functions and actions are not required, this component is not an essential component for the coating material composition of the present invention.
Filler G can be purchased as a commercial product or can be prepared by common chemical methods.
The filler G may be a single type or a mixture of two or more types.

The filler G may be any filler as long as it exhibits the above-mentioned functions and effects, and examples thereof include, but are not limited to, non-reinforcing fillers, preferably fillers having a BET surface area of up to 50 m2/g, such as quartz, silica sand, diatomaceous earth, calcium silicate, zirconium silicate, talc, kaolin, zeolite, metal oxide powders, such as aluminum oxide, titanium oxide, iron oxide, or zinc oxide and/or mixed oxides thereof, barium sulfate, calcium carbonate, gypsum, silicon nitride, silicon carbide, boron nitride, glass powders and polymer powders, such as polyacrylonitrile powder; reinforcing fillers, fillers having a BET surface area of more than 50 m2/g, such as pyrogenically prepared silica, precipitated silica, precipitated calcium carbonate, carbon black, such as furnace black and acetylene black, and mixed silicon/aluminum oxides with high BET surface areas; fillers in the form of hollow beads of aluminum trihydroxide, such as those available from 3M Deutschland, Neuss, Germany. magnetic microbeads, examples of which are available under the trade name Zeeospheres™ from AKZONOBEL, Expancel, Sundsvall, Sweden, elastic polymer beads, for example those available under the trade name EXPANCEL®, or glass beads; fillers in the form of fibres, for example asbestos and also polymer fibres.
The above mentioned fillers may be hydrophobized, for example, by treatment with organosilanes and/or organosiloxanes, or with stearic acid, or by etherification of hydroxyl groups to alkoxy groups.

Fillers G are preferably calcium carbonate, talc, aluminum hydroxide and silica, with calcium carbonate being particularly preferred. Preferred grades of calcium carbonate are ground or precipitated, optionally surface-treated with fatty acids such as stearic acid or their salts. Preferred silicas are preferably pyrogenic (fumed) silicas.

Filler G preferably has a moisture content of less than 1 part by weight, more preferably less than 0.5 parts by weight.

The content of filler G in the entire composition is preferably in the range of 0 to 80 parts by mass. More preferably, it is in the range of 0 to 60 parts by mass. Within this range, there is a low possibility of defects in the coating material, such as poor adhesion or cracking of the film, and the viscosity during production is appropriate, allowing for uniform stirring.

The curing catalyst H is a component that functions as a curing catalyst for the moisture-curable composition of the present invention. This component is not an essential component for the moisture-curable composition of the present invention when the above-mentioned functions and actions are not required, but is an effective component when the reactivity of the silane-terminated modified polymer (A) is low.
The curing catalyst H can be purchased as a commercial product or can be prepared by conventional chemical methods.
The curing catalyst H may be a single component or a mixture of two or more components.

The curing catalyst H may be any one that exhibits the above-mentioned functions and actions, and is not limited thereto. Examples of metal-containing components H are organotitanium and organotin compounds, such as titanate esters, e.g., tetrabutyl titanate, tetrapropyl titanate, tetraisopropyl titanate, and titanium tetraacetylacetonate; tin compounds, e.g., dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, dibutyltin dioctanoate, dibutyltin acetylacetonate, dibutyltin oxide, and the corresponding dioctyltin compounds.

Examples of metal-free curing catalysts H are basic compounds such as triethylamine, tributylamine, 1,4-diazabicyclo[2.2.2]octane, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undec-7-ene, N,N-bis-(N,N-dimethyl-2-aminoethyl)methylamine, N,N-dimethylcyclohexylamine, N,N-dimethylphenylamine and N-ethylmorpholinine.

As hardening catalyst H it is likewise possible to use acidic compounds, such as phosphoric acid and its esters, toluenesulfonic acid, sulfuric acid, nitric acid, or other organic carboxylic acids, such as acetic acid and benzoic acid.

The content of curing catalyst H in the entire composition is preferably in the range of 0 to 5 parts by mass. If it exceeds 5 parts by mass, application problems may occur due to a shortened pot life, wrinkles may occur on the coating surface, and problems such as thickening, gelling, and hardening may occur during storage. A range of 0 to 0.2 parts by mass is more preferable.

In addition to the above-mentioned components, the moisture-curable composition of the present invention may contain any other components as long as the object of the present invention is achieved. For example, it may contain all other substances such as defoamers, curing speed regulators, additives, adhesion improvers, and adjuvants. In some cases, components that improve adhesion, such as epoxy silanes, may also be added.

The laminate according to the present invention has a structure in which a cured product is formed by curing the moisture-curable composition on a substrate, and a topcoat layer is disposed on the surface of the cured product, so that the substrate and the cured product, and the cured product and the topcoat layer are in close contact with each other.

The moisture-curing composition forms a matrix (a three-dimensional network structure) by reacting with moisture at room temperature, and hardens into a cured product. In addition to being used as a construction sealant, such moisture-curing compositions are used as sealants, adhesives, coatings, and sealants for vehicles such as buses, trucks, and passenger cars, as well as trains, ships, and containers. Their use in automobiles and railroad cars is particularly important from an industrial perspective.

The manufacturing process of an automobile is roughly divided into a body assembly process, a painting process, an assembly process, etc. Among these processes, the moisture-curable composition is particularly used in the painting process.
The moisture-curable composition is also used in the repair process of vehicles such as automobiles, ships, containers, and the like.

In the painting and repair processes, the curable composition is applied to a substrate (such as a car body) for purposes such as waterproofing and rust prevention, and is cured by curing at room temperature. A topcoat layer is then applied onto the car body and the cured moisture-curable composition, and the cured product and the topcoat layer are bonded together.

That is, a laminate is produced using the moisture-curable composition in a method including the following steps 1 to 3.

(Step 1)
Step 1 is a step of applying a moisture-curable composition containing the above-mentioned silane-modified polymer A and aminosilane B to a substrate.

Examples of substrates include inorganic substrates such as glass, aluminum, stainless steel, zinc, copper, mortar, vehicle body frames, and vehicle body panels, as well as organic substrates. Organic substrates include polyvinyl chloride, acrylic resin, polyester, polyethylene, polypropylene, and polycarbonate.

The moisture-curable composition to be applied may be a one-part curable composition, or may be a composition prepared by mixing two-part compositions.
The coating method is not particularly limited, and can be any known method.

(Step 2)
Step 2 is a step of curing the curable composition applied in step 1 at room temperature to cure it.

There are no particular limitations on the curing temperature, but room temperature is preferred, 0°C to 40°C is more preferred, 10°C to 35°C is even more preferred, and 15°C to 30°C is most preferred.

There are no particular limitations on the curing time, as long as at least the surface of the moisture-curable composition is cured. 1 to 48 hours is preferred, 2 to 36 hours is more preferred, 5 to 24 hours is even more preferred, and 12 to 24 hours is most preferred.

(Step 3)
Step 3 is a step of applying a topcoat layer onto the cured product of the curable composition cured in step 2. After applying the topcoat layer, a heat curing step can be carried out as necessary. The heat curing temperature can be appropriately selected depending on the properties of the curable composition and the topcoat layer, and may be, for example, 100°C or higher, or 100°C to 200°C.
From the viewpoint of curing the coating material in a short time, the curing temperature is, for example, preferably 160°C to 230°C, and more preferably 180°C to 220°C.
The curing time is preferably from 10 minutes to 5 hours, more preferably from 10 minutes to 3 hours, and even more preferably from 10 minutes to 1 hour.

The present invention will be specifically explained by showing examples and comparative examples and listing the results in Table 1, but the present invention is not limited to the following examples.

<How to prepare test specimens to evaluate adhesion with topcoat materials>
The moisture-curing compositions obtained in the Examples and Comparative Examples were applied to an aluminum substrate to a thickness of approximately 2 mm, and then aged for one day under standard conditions (23±2°C, 50±5% RH). An acrylic urethane paint (Kansai Paint, Retan PG Eco Deep Black) was applied with a brush (application amount approximately 100 g/ ^m2 ) as a topcoat (i.e., topcoat layer) to the cured moisture-curing compositions, and after 15 minutes, the composition was dried at 60°C for 30 minutes, and then aged for another day under standard conditions.

<Method for evaluating adhesion to topcoat material>
The adhesiveness was evaluated according to the cross-cut method of JIS K5600-5-6. When the evaluation classification was 0 or 1, the adhesiveness was judged to be acceptable.
The coating film on the surface of the test piece was cut into a grid of 100 squares spaced 1 mm apart, adhesive tape was applied thereon, and the adhesive tape was subsequently peeled off to evaluate the adhesion based on the degree of peeling according to the following criteria.
Category 0: The edges of the cut are completely smooth and there is no spalling on any of the grid cells.
Class 1: There is more than 0% and less than 5% peeling in the cross-cut area.
Category 2: More than 5% to 15% peeling occurs in the cross-cut area.
Class 3: Peeling of more than 15% and up to 35% occurs in the cross-cut area.
Class 4: More than 35% to 65% peeling occurs in the cross-cut area.
Category 5: The degree of peeling exceeds category 4.

Example 1
The moisture-curable composition used was composed of the following components:
The mixture was prepared by mixing 25.0 parts by mass of GENIOSIL (registered trademark) STP-E30 manufactured by Wacker Chemie AG (having a viscosity of 30,000 mPa·s at 25° C.; in the above general formula (1), Y is a divalent organic polymer group bonded via a urethane group containing an oxyalkylene group as a polymer chain, R ¹ and R ² are both methyl groups, a = 1, and x = 2) as the silane-modified polymer A, 23.5 parts by mass of polypropylene glycol (diol type, molecular weight 2000) manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd. as the plasticizer D, 2.0 parts by mass of GENIOSIL (registered trademark) XL10 (vinyltrimethoxysilane) manufactured by Wacker Chemie AG as the vinylsilane-based dehydrating agent E, and Tinuvin (registered trademark) manufactured by BASF Japan Ltd. as the stabilizer F. Moisture-curing composition 1 was prepared by adding 1.0 part by mass of B75, 22.0 parts by mass of Softon 2200 manufactured by Bihoku Funka Kogyo Co., Ltd. as filler G, 22.0 parts by mass of Hakuenka CCR manufactured by Shiraishi Calcium Co., Ltd., 2.0 parts by mass of HDK (registered trademark) H18 manufactured by Wacker Chemie AG as thixotropic adjuster C, and 2.5 parts by mass of GENIOSIL (registered trademark) GF94 (3-(2-aminomethylamino)propyltriethoxysilane) manufactured by the same company as aminosilane B, and stirring uniformly.
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)

As a result of the topcoat adhesion evaluation of moisture-curable composition 1, the evaluation classification was 0, so the adhesion to the topcoat material was deemed to be acceptable.

Example 2
Except for using 23.5 parts by mass of Hexamoll (registered trademark) DINCH (registered trademark) (1,2-cyclohexanedicarboxylic acid diisononyl ester) manufactured by BASF Japan Ltd. as plasticizer D, the same components, mass parts, and preparation method as in Example 1 were used to obtain moisture-curable composition 2, which was then evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 2, the evaluation category was 1, so the adhesion to the topcoat material was deemed to be acceptable.

<Comparative Example 1>
As aminosilane B, 2.5 parts by mass of GENIOSIL (registered trademark) GF93 (3-aminopropyltriethoxysilane) manufactured by the same company was used, but all other parts by mass and preparation methods were the same as in Example 1, to obtain moisture-curable composition 3, which was evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 3, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 2>
As aminosilane B, 2.5 parts by mass of GENIOSIL (registered trademark) GF93 (3-aminopropyltriethoxysilane) manufactured by the same company was used, but all other parts by mass and preparation methods were the same as in Example 2, a moisture-curing composition 4 was obtained and evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 4, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 3>
As aminosilane B, 2.5 parts by mass of GENIOSIL (registered trademark) GF91 (N-(2-aminoethyl)-3-aminopropyltrimethoxysilane) manufactured by the same company was used, but all other parts by mass and preparation methods were the same as in Example 1, a moisture-curing composition 5 was obtained, and a similar evaluation was performed.

As a result of the topcoat adhesion evaluation of moisture-curable composition 5, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 4>
As aminosilane B, 2.5 parts by mass of GENIOSIL (registered trademark) GF95 (N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane) manufactured by the same company was used, but all other parts by mass and preparation methods were the same as in Example 1, to obtain moisture-curable composition 6, which was evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 6, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 5>
As aminosilane B, 2.5 parts by mass of GENIOSIL (registered trademark) GF96 (3-aminopropyltrimethoxysilane) manufactured by the same company was used, but all other parts by mass and preparation methods were the same as in Example 1, to obtain moisture-curable composition 7, which was evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 7, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 6>
Except for using 23.5 parts by mass of Hexamoll (registered trademark) DINCH (1,2-cyclohexanedicarboxylic acid diisononyl ester) manufactured by BASF Japan Ltd. as plasticizer D, all the components, parts by mass and preparation method were the same as those in Comparative Example 5. A moisture-curable composition 8 was obtained and evaluated in the same manner.

As a result of the topcoat adhesion evaluation of moisture-curable composition 8, the evaluation category was 5, so the adhesion to the topcoat material was deemed to be unsatisfactory.

<Comparative Example 7>
As the silane-modified polymer, 25.0 parts by mass of GENIOSIL (registered trademark) STP-E35 manufactured by Wacker Chemie AG, in which three methylene groups are directly bonded to a reactive silicon group (viscosity is 30,000 mPa·s at 25 ° C., in the following general formula (5), Y is a divalent organic polymer group bonded via a urethane group containing an oxyalkylene group as a polymer chain, R ¹ and R ² are both methyl groups, a = 0, and x = 2) was used, and 0.2 parts by weight of Neostan U810 (dioctyltin dilaurate) manufactured by Nitto Kasei Co., Ltd. was used as the curing catalyst (J). The same components, parts by mass and preparation method were used as in Comparative Example 5, and a moisture-curable composition 9 was obtained and evaluated in the same manner.
Y-[(CH ₂ ) ₃ -SiR ¹ _a (OR ² ) _3-a ] _x (5)

As a result of the topcoat adhesion evaluation of moisture-curable composition 9, the evaluation category was 0, indicating good adhesion to the topcoat material. When using a silane-modified polymer with three methylene groups, the aminosilane contains one amino group, and even a compound containing a methoxy group shows good adhesion, but the problem is that it cannot be cured without using a curing catalyst containing harmful tin.

These results confirm that when a moisture-curing composition containing a polyoxyalkylene polymer with one methylene group directly attached to an alkoxysilane terminal group is used as a sealant, adding an aminosilane with two or more amino groups and one or more ethoxy groups improves adhesion to the topcoat layer to the extent that it achieves classification 0 or 1 in the JIS K5600-5-6 cross-cut method.

Claims (3)

A moisture-curable composition for forming a cured product for applying a topcoat layer to a surface, comprising:
(A) a compound represented by the following general formula (1):
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a group having a polymer chain which is polyoxyalkylene and is bonded to the group -[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] by -O-C(═O)-NH- or -NH-C(═O)-NR'-;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
R' is a monovalent, optionally substituted SiC-bonded hydrocarbon radical;
x is an integer from 1 to 10;
a is 0, 1, or 2.
and a silane-modified polymer A of
(B) an aminosilane or amino-modified silicone having an alkoxy group having two or more carbon atoms and two or more amino groups,
The hydrolysis rate of the component (B) is slower than the hydrolysis rate of the component (A), thereby improving adhesion between the top coat layer and a cured product obtained by curing the moisture-curable composition. A method for producing a laminate by bonding a topcoat layer to a cured product obtained by curing a moisture-curable composition containing a silane-modified polymer A represented by the following general formula (1) and an aminosilane or amino-modified silicone B having an alkoxy group having two or more carbon atoms and two or more amino groups, comprising:
applying the moisture-curable composition to a substrate;
a step of forming a matrix by hardening the component (A) and a portion of the component (B) with moisture;
a step in which the remainder of the component (B) migrates to the surface of the cured product formed in the step of forming the matrix, and amino groups derived from the component (B) are oriented in the vicinity of the surface of the cured product;
A step in which the amino groups oriented on the surface of the cured product interact with a topcoat layer;
A method comprising:
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2. A method for improving adhesion between a cured product obtained by curing a moisture-curable composition and a top coat layer, comprising the steps of:
The moisture-curable composition includes a silane-modified polymer A represented by general formula (1) and an aminosilane or amino-modified silicone B having an alkoxy group having two or more carbon atoms and two or more amino groups ,
the hydrolysis rate of the aminosilane B is slower than the hydrolysis rate of the silane-modified polymer;
applying the moisture-curable composition to a substrate;
a step of forming a matrix by hardening the component (A) and a portion of the component (B) with moisture;
a step in which the remainder of the component (B) migrates to the surface of the cured product formed in the step of forming the matrix, and amino groups derived from the component (B) are oriented in the vicinity of the surface of the cured product;
A step in which the amino groups oriented on the surface of the cured product interact with a topcoat layer;
A method comprising:
Y-[CH ₂ -SiR ¹ _a (OR ² ) _3-a ] _x (1)
(Wherein,
Y is a polymeric group having a valence of x attached through nitrogen, oxygen, or sulfur;
^R1 , which may be the same or different, are monovalent, optionally substituted, SiC-bonded hydrocarbon radicals;
^R2 , which may be the same or different, is a hydrogen atom or a monovalent, optionally substituted hydrocarbon group;
x is an integer from 1 to 10;
a is 0, 1, or 2.