JPH0548792B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a coating composition that has surface properties such as water and oil repellency, stain resistance, and non-adhesion, and is capable of forming a coating film with excellent weather resistance. It is. [Prior Art] In the field of paints, coating films with surface properties such as water and oil repellency, stain resistance, and non-adhesion are sometimes required. These surface properties have been achieved in other technical fields, for example in the textile processing field, by using polymers containing polyfluoroalkyl groups, especially perfluoroalkyl groups.
Therefore, in order to impart these surface properties to coating films, it has been considered to apply polymers having perfluoroalkyl groups to coatings. However, it has been difficult to exhibit sufficient weather resistance with conventional coatings using polymers having perfluoroalkyl groups. For example, a perfluoroalkyl group-containing polymer is mixed into a general-purpose paint (see Japanese Patent Publication No. 58-50269), or a paint whose main component is a perfluoroalkyl group-containing polymer (Japanese Patent Publication No. 48-4528). However, in these cases, the weather resistance of the coating film is not sufficiently high. Furthermore, in JP-A-48-4528, etc., a functional group-containing monomer is used as a perfluoroalkyl group-containing polymer to react with a crosslinking component such as an amino resin to form a cured coating film with a three-dimensional network structure. Although a copolymerized product is used, the crosslinking component belongs to the category of general-purpose paints, and it is influenced by the physical properties of the perfluoroalkyl group-containing polymer itself, which is the main component, so it does not necessarily have sufficient weather resistance. Sexuality is difficult to achieve. Furthermore, JP-A No. 59-189108 discloses weather resistance in which a polymer having a perfluoroalkyl group and a hydroxyl group is used in combination with a hydroxyl group-containing fluorine-containing polymer to be cured with a polyisocyanate compound such as hexamethylene diisocyanate. High-quality paints are listed. However, the weather resistance of this paint mainly depends on the hydroxyl group-containing fluorine-containing polymer, and in order to ensure compatibility with this polymer, the length of the perfluoroalkyl group of the polymer containing perfluoroalkyl groups is adjusted. It was difficult to increase the length, and it was difficult to fully exhibit the above-mentioned surface properties. Moreover,
The polyisocyanate compound used as a curing agent is simply a repurposed curing agent for conventional general-purpose paints, and it has also been a cause of deteriorating the inherent weather resistance of the hydroxyl group-containing fluorine-containing polymer. In other words, the weather resistance of general-purpose curing agents is considerably lower than that of hydroxyl group-containing fluoropolymers, and if a relatively large amount of curing agents is used, there is a risk that the weather resistance of the coating film will be significantly reduced. . Furthermore, since curing agents are usually low-molecular compounds, they often have insufficient compatibility with hydroxyl group-containing fluorine-containing polymers, resulting in problems such as slow reaction rates. [Problems to be Solved by the Invention] The purpose of the present invention is to provide a novel coating composition containing a polymer having a highly reactive functional group and a polyfluoroalkyl group, which have not been known in the past. It is something to do. When this novel polymer is used in combination with a component capable of bonding with its highly reactive functional groups, a coating film containing polyfluoroalkyl groups is produced. This polymer can be used by being dissolved in a solvent, and furthermore, since it has a highly reactive functional group that can react at room temperature, it can be made into a room-temperature curing type paint. Of course, it is also possible to use a heat-curable paint. However, this polymer has higher weather resistance than conventional compounds having highly reactive functional groups, making it possible to obtain a coating film with high weather resistance. In the case of paints using the hydroxyl group-containing fluorine-containing polymer, the weather resistance of the curing agent that bonds with the hydroxyl groups to provide crosslinking is insufficient, and the weather resistance of the hydroxyl group-containing fluorine-containing polymer as a whole cannot be improved. However, by using the above polymer with high weather resistance, this problem of reduced weather resistance can be solved. Moreover, since the above-mentioned polymer having a polyfluoroalkyl group and a highly reactive functional group is a compound with a relatively high molecular weight, it is highly compatible with the hydroxyl group-containing fluorine-containing polymer, and the above-mentioned problems due to compatibility arise. is also resolved. In addition to these characteristics, as mentioned above, the highly weather-resistant coating films obtained using conventional hydroxyl group-containing fluorine-containing polymers have surface properties such as water and oil repellency and stain resistance that impair their weather resistance. Add without
Moreover, it becomes possible to obtain a coating film that maintains its surface properties for a long period of time. [Means for Solving the Problems] The present invention is a coating composition containing the specified polymer, that is, the blending ratio of the following copolymer and compound is /=2 to 98/ by weight. A coating composition containing a polymer and a compound having a molecular weight of 2 to 98. A copolymer in which the copolymerization ratio of the following is 5 to 98/2 to 80/0 to 90 in molar ratio, an isocyanate group-containing vinyl monomer, and a polyfluoroalkyl group having 3 carbon atoms.
A vinyl monomer containing ~20 polyfluoroalkyl groups A copolymerizable monomer other than the above A compound having a functional group capable of bonding with the isocyanate group The polymer having an isocyanate group and a polyfluoroalkyl group in the present invention has an isocyanate group It consists of a copolymer of a polyfluoroalkyl group-containing vinyl monomer, a polyfluoroalkyl group-containing vinyl monomer, and, optionally, a monomer that does not further contain these groups. Isocyanate group-containing vinyl monomers and copolymers thereof, polyfluoroalkyl group-containing vinyl monomers and copolymers thereof are well known, but copolymers of isocyanate group-containing vinyl monomers and polyfluoroalkyl group-containing vinyl monomers and their 2 Copolymers of species monomers with further copolymer monomers are not known. Isocyanate group-containing vinyl monomers and their sole or copolymers are known, for example, in JP-A-56-118409, JP-A-59-227910,
JP-A-60-6712, U.S. Patent No. 2718516, U.S. Patent No. 4222909, U.S. Patent No.
It is described in the specification of No. 4436885. As a specific isocyanate group-containing vinyl monomer,
These known examples include isocyanate alkyl methacrylate, isocyanate alkyl acrylate, and isopropenyl-α,α-dimethylbenzyl isocyanate. Preferred isocyanate group-containing vinyl monomers in the present invention are methacrylate-based or acrylate-based compounds that provide polymers with higher weather resistance than other polymers, and in particular are methacrylate-based or acrylate-based compounds that have an isocyanate group and have 2 to 8 carbon atoms (isocyanate group methacrylates and acrylates having linear, branched or cyclic alkyl groups (excluding carbon atoms), specifically, for example, isocyanate ethyl methacrylate, isocyanate ethyl acrylate, isocyanate butyl methacrylate, isocyanate butyl acrylate, etc. Examples include isocyanate hexyl methacrylate and isocyanate hexyl methacrylate. Particularly preferred are these compounds having an isocyanate alkyl group having an isocyanate group at the end of the alkyl group (ie, an ω-isocyanate alkyl group), and 2-isocyanate ethyl methacrylate is most preferred. The polyfluoroalkyl group-containing vinyl monomer in the present invention is composed of various vinyl monomers having a polyfluoroalkyl group, such as methacrylate, acrylate, vinyl ester, vinyl ether, and the like. This particularly preferred vinyl monomer is a vinyl monomer that is easily copolymerized with the isocyanate group-containing vinyl monomer, and in this sense, methacrylate-based or acrylate-based vinyl monomers are preferred. The next preferred vinyl monomer is a vinyl ester monomer. The polyfluoroalkyl group is preferably a perfluoroalkyl group (hereinafter referred to as R _f ), but in addition, the number of all hydrogen atoms in the alkyl group is approximately
More than 50%, preferably about 75% or more, are substituted with fluorine atoms (some of the remaining hydrogen atoms ~
Polyfluoroalkyl groups (all of which may be substituted with chlorine atoms, etc.) are preferred. This perfluoroalkyl group and polyfluoroalkyl group may be a branched group or a linear group. The number of carbon atoms in these groups is 3 to 20, and in the case of perfluoroalkyl groups, the number of carbon atoms is preferably 3 to 16, most preferably about 3 to 10. The compound having a perfluoroalkyl group will be explained below. The methacrylate and acrylate having a perfluoroalkyl group are preferably compounds represented by the following formula []. R _f -X-OCOC(R ¹ )=CH ₂ ...[] R ¹ is a hydrogen atom or a methyl group. X is a divalent bonding group, and is preferably a group represented by ^-R2- , -CON( ^R3 )-Q-, or particularly _-SO2N ( ^R3 )-Q-. R ² is a linear or branched alkylene group, and particularly preferably a linear alkylene group having 2 to 4 carbon atoms. R ³ is an alkyl group, and particularly preferably an alkyl group having 1 to 4 carbon atoms. Q is a divalent organic group that can be bonded to a residue of methacrylic acid or acrylic acid through an ester bond; for example, a linear, branched, or cyclic alkylene group, -CON(R ³ ) in an aromatic nucleus. -ya-
Examples include arylalkyl groups to which SO ₂ N(R ³ )- is bonded. Q is preferably a branched or linear alkylene group having 12 or less carbon atoms, particularly preferably a linear alkylene group having 2 to 8 carbon atoms. Examples of polyfluoroalkyl group-containing vinyl monomers other than those mentioned above include compounds in which X and Q are alkylene groups having a substituent (for example, acyloxy group or alkoxy group) in the above formula [], and compounds where X and Q are polyoxyalkylene groups. There are compounds that have a chain, or compounds that are polyfluoroalkyl groups that have a hydrogen atom or a chlorine atom instead of the R _f group. Further, as compounds other than methacrylates and acrylates, there are vinyl esters and vinyl ethers of carboxylic acids having polyfluoroalkyl groups. For example, a vinyl ester of perfluorocarboxylic acid represented by R _f COOCH ₂ =CH ₂ can be used. It is necessary that the polyfluoroalkyl group-containing vinyl monomer does not have a functional group that can react with an isocyanate group. Therefore, for example, a compound having a hydroxyl group cannot be used because the hydroxyl group and the isocyanate group react with each other. Some specific examples of the polyfluoroalkyl group-containing vinyl monomer in the present invention are shown below, but the invention is not limited to these compounds. CF ₃ (CF ₂ ) ₄ CH ₂ OCOC (CH ₃ ) = CH ₂ CF ₃ (CF ₂ ) ₆ (CH ₂ ) ₂ OCOC (CH ₃ ) = CH ₂ CF ₃ (CF ₂ ) ₆ COOCH = CH ₂ CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ ) ₂ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₄ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₇ SO ₂ N( _CH3 )( _CH2 ) _2OCOC ( _CH3 )=
CH ₂ CF ₃ (CF ₂ ) ₇ SO ₂ N (C ₂ H ₅ ) (CH ₂ ) ₂ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₇ CON (CH ₃ ) (CH ₂ ) ₂ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ OCOCH=CH ₂ CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ OCOC(CH ₃ )=CH ₂ CF ₃ (CF ₂ ) ₈ CON(C ₂ H ₅ ) (CH ₂ ) ₂ OCOC (CH ₃ )=
CH ₂ H(CF ₂ ) ₁₀ CH ₂ OCOCH=CH ₂ CF ₂ Cl(CF ₂ ) ₁₀ CH ₂ OCOC(CH ₃ )=CH ₂ The isocyanate group-containing vinyl monomer and polyfluoroalkyl group-containing vinyl monomer are:
The desired polymer can be obtained by copolymerizing only two of them (however, each may be a combination of two or more compounds). However, if necessary, it is also possible to further combine copolymerizable monomers other than these two types to form a ternary or more copolymer. For example, copolymerizable monomers are used for the purpose of improving the solubility of the polymer in other coating components, improving the solubility in coating solvents, and changing the physical properties of the coating film. This copolymerizable monomer is different from the above two types of monomers, and is a monomer that does not have a functional group reactive with an isocyanate group. For example, methacrylate-based or acrylate-based monomers, olefins such as styrene, ethylene, and propylene, vinyl ethers such as alkyl vinyl ethers, haloolefins such as fluoroolefins and chloroolefins, and dienes such as butadiene can be used. Particularly preferred copolymerizable monomers are methacrylate-based or acrylate-based monomers that have good copolymerizability. For example, methyl methacrylate, methyl acrylate, butyl methacrylate, butyl acrylate, 2-ethylhexyl acrylate, chloroethyl methacrylate, chloroethyl acrylate, benzyl methacrylate, etc. can be used. The copolymerization ratio of the isocyanate group-containing vinyl monomer, polyfluoroalkyl group-containing vinyl monomer, and other copolymerizable monomers is: isocyanate group-containing vinyl monomer/polyfluoroalkyl group-containing vinyl monomer/copolymerizable monomer expressed as a molar ratio of 5 to 98/2 to
80/0~90, especially about 15~95/5~60/0~
80 is preferred. Further, the proportion of the isocyanate group-containing vinyl monomer is approximately 30 to 90 mol% based on the total monomers in order to obtain sufficient crosslinking density and to ensure pot life and storage stability. Further, the proportion of the polyfluoroalkyl group-containing vinyl monomer is preferably about 10 to 50 mol % based on the total monomers in order to exhibit sufficient surface properties and improve solubility in solvents and the like. The proportion of other copolymerizable monomers is particularly preferably about 0 to 60 mol%.
Copolymerization of these monomers can be carried out in a customary manner. For example, polymerization is carried out in a solvent or dispersion medium in the presence of a polymerization initiator, using a chain transfer agent such as a mercaptan if necessary, to obtain the desired polymer. The molecular weight of the obtained polymer is not particularly limited, but it is suitably about 1,000 to 50,000, especially about
2000-20000 is preferable. However, on average, at least about 2 isocyanate groups are required in one molecule of the polymer, and polymers having about 4 to 100 isocyanate groups are particularly preferred. Therefore, when the molar ratio of the isocyanate group-containing vinyl monomer is small, a relatively high molecular weight polymer is used. Furthermore, on average, at least about 1
It is preferable that about 1 polyfluoroalkyl group is present, particularly about 1 polyfluoroalkyl group on average in one polymer molecule.
Preferably there are ~50 polyfluoroalkyl groups. It goes without saying that the above-mentioned polymer having an isocyanate group and a polyfluoroalkyl group can be used as it is as a coating component, but if necessary, the isocyanate group may be blocked with a blocking agent before use. The isocyanate group blocked with the blocking agent is removed by heating or the like and becomes a free isocyanate group. Polymers having such blocked isocyanate groups can be applied to coatings such as heat-curable coatings, one-component coatings, and powder coatings. As the blocking agent, compounds capable of blocking various isocyanate groups can be used, such as phenols, lactams, bisulfites, and the like. The coating composition of the present invention contains the above polymer having an isocyanate group and a polyfluoroalkyl group, as well as a compound capable of bonding with the isocyanate group. Examples of functional groups that can bond with this isocyanate group include hydroxyl group, carboxylic acid group, amino group,
There are imino groups, mercapto groups, and other functional groups containing active hydrogen atoms. This compound must have two or more of these functional groups, such as polyol, polyphenol, polycarboxylic acid, polyamine, polythiol, and two or more other functional groups (they may be different functional groups). It is a compound having the following properties. As these compounds, compounds used in conventional polyurethane paints are suitable. Preferred compounds are polyols, such as polyester polyols, polyether polyols, acrylic polyols,
These include oil-modified polyols, hydroxyl group-containing hydrocarbon associations, and other compounds having two or more alcoholic hydroxyl groups. Specifically, polyester polyols having polyhydric alcohol residues and polycarboxylic acid groups, polyester polyols consisting of ring-opening polymers of cyclic esters such as ε-caprolactone, or polymers of hydroxycarboxylic acids, etc. Polyether polyols obtained by adding epoxides or cyclic ethers to alcohols, polyhydric phenols, amines, etc.; combinations of methacrylates and acrylates with hydroxyalkyl groups and other methacrylates, acrylates, and other copolymerizable monomers; Acrylic polyols made of copolymers, polyester or polyether polyols modified with oils such as castor oil, hydrocarbon polymers with two or more hydroxyl groups such as polybutadiene glycol, and polyhydric alcohols and castor oil. There are compounds with relatively low molecular weight. Also preferred are polyamides, polyamines, alkanolamines, other amine compounds, and polyepoxy compounds such as epoxy resins.
Useful coating films having the above-mentioned surface properties can be obtained by combining these compounds with the above-mentioned compounds having isocyanate groups and polyfluoroalkyl groups in place of conventional polyisocyanate compounds. In order to obtain a coating film with particularly high weather resistance, it is preferable to use a hydroxyl group-containing fluorine-containing polymer as the compound having a functional group capable of bonding with the isocyanate group. Hydroxyl group-containing fluorine-containing polymers that can be used as components of this paint are known, and are described, for example, in JP-A-57-34107, JP-A-59-189108, JP-A-60-67518, etc. has been done. Although these hydroxyl group-containing fluorine-containing polymers have extremely high weather resistance, the above-mentioned surface properties are not sufficient, and the use of polyisocyanate compounds, which are conventionally known curing agents, has been a cause of reduced weather resistance. If this hydroxyl group-containing fluorine-containing polymer is used as a compound having a functional group capable of bonding with an isocyanate group in the present invention, there is little risk of deteriorating the weather resistance of the hydroxyl group-containing fluorine-containing polymer, and coatings with extremely high weather resistance can be obtained. Along with obtaining a membrane,
It becomes possible to impart water and oil repellency and stain resistance to coating films conventionally obtained using hydroxyl group-containing fluorine-containing polymers. As the hydroxyl group-containing fluorine-containing polymer, a monomer which essentially includes a polyfluoroolefine and a hydroxyl group-containing vinyl ether, and preferably a vinyl ether that does not further contain a hydroxyl group, is used, and these two to
A polymer obtained by copolymerizing three types of monomers as main components is used. Each of these two to three types of monomers may be composed of two or more monomers. Suitable polyfluoroolefins include polyfluoroolefins having 2 to 3 carbon atoms, such as tetrafluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, and hexafluoropropylene, with tetrafluoroethylene and chlorotrifluoroethylene being particularly preferred. As the hydroxyl group-containing vinyl ether, hydroxyalkyl vinyl ethers are suitable, and vinyl ethers having a hydroxyalkyl group having 3 to 8 carbon atoms are particularly preferred. Specifically, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether,
Examples include hydroxyisopropyl vinyl ether and hydroxy-2-methylbutyl vinyl ether. A particularly preferred hydroxyl group-containing vinyl ether is n
-Hydroxybutyl vinyl ether. The hydroxyl group-containing fluorine-containing polymer can be obtained from two types of monomers, the above-mentioned polyfluoroolefin and hydroxyl group-containing vinyl ether, but is preferably further copolymerized with another copolymerizable monomer. As the copolymerizable monomer, vinyl ether having no hydroxyl group is particularly preferred, but the copolymerizable monomer is not limited thereto. Vinyl ethers without hydroxyl groups may also be vinyl ethers with fluorine atoms. These vinyl ethers include linear,
Examples include vinyl ethers having an alkyl group which may have a branched or cyclic fluorine atom, such as alkyl vinyl ethers, cycloalkyl vinyl ethers, and poly(or mono)fluoroalkyl vinyl ethers. Preferred compounds include vinyl ethers having a linear or branched alkyl group having 1 to 10 carbon atoms, especially 2 to 6 carbon atoms, cycloalkyl vinyl ethers which may have a side chain having 6 to 10 carbon atoms, and cycloalkyl vinyl ethers having 2 or more carbon atoms. It is a polyfluoroalkyl vinyl ether having 3 to 6 carbon atoms. Specific examples include ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, cyclohexyl vinyl ether, and 2,2,3,3-tetrafluoropropyl vinyl ether. Further, polyfunctional vinyl ethers such as divinyl ether can be used together with or in place of these vinyl ethers. Particularly preferred vinyl ethers having no hydroxyl group are ethyl vinyl ether, butyl vinyl ether, and cyclohexyl vinyl ether. In addition, copolymerizable monomers other than vinyl ether can also be used in place of or together with these vinyl ethers that do not have a hydroxyl group. For example, alkyl methacrylate, alkyl methacrylate,
Alkyl acrylates, olefins, and other copolymerizable monomers can be used. However, the use of copolymerizable monomers other than vinyl ether often reduces the solubility and other properties of the hydroxyl group-containing fluorine-containing copolymer, and even if it is used, it is used in small amounts (for example, less than about 5 mol% of the raw monomer). ) is preferred and is usually not substantially used. The copolymerization ratio of polyfluoroolefin/hydroxyl group-containing vinyl ether/copolymerizable monomer is preferably about 30 to 70/1 to 45/0 to 69 expressed in mol %. In particular, it is preferably about 40-60/3-40/5-57, and most preferably about 40-60/5-20/20-50. The polymerization method is preferably carried out by the method described in the above-mentioned publication. The resulting hydroxyl group-containing fluorine-containing polymer is usually solvent soluble. 30 of this polymer in tetrahydrofuran
Preferably, the intrinsic viscosity, measured at °C, is in the range of about 0.05 to 2.0 dl/g. The coating composition of the present invention consists of two components: a polymer having the isocyanate group and a polyfluoroalkyl group (hereinafter referred to as NCO-containing polymer) and a compound having a functional group capable of bonding with the isocyanate group (hereinafter referred to as active hydrogen compound). This is a composition containing as an essential component. This composition is usually used after being dissolved in a solvent, but it may also be dispersed in a dispersion medium as described above, or it can be made into a powdered composition. In addition, various additives can be added in the same manner as in ordinary coating compositions. The blending ratio of the NCO-containing polymer and the active hydrogen compound is 2-98/2-98, expressed as a weight ratio of NCO-containing polymer/active hydrogen compound. A particularly preferred weight ratio is about 10-90/10-90. The number of isocyanate groups in the NCO-containing polymer per functional group capable of bonding with the isocyanate group of the active hydrogen compound is preferably about 0.2 to 5, particularly about 0.6 to 3. When the hydroxyl group-containing fluorine-containing polymer is used as the active hydrogen compound, approximately 5 parts of the NCO-containing polymer is added per 100 parts by weight of the hydroxyl group-containing polymer.
It is preferred to use ~100 parts by weight, especially about 10 to 60 parts by weight. The number of isocyanate groups in the NCO-containing polymer per hydroxyl group in the hydroxyl-containing fluorine-containing polymer is particularly preferably about 0.8 to 2.5. As the active hydrogen compound, a hydroxyl group-containing fluorine-containing polymer and another active hydrogen compound can also be used in combination. By using other active hydrogen compounds in combination, the weather resistance of the coating film is usually lower than when only the hydroxyl group-containing fluorine-containing polymer is used.
On the other hand, it becomes possible to improve other physical properties of the coating film, such as imparting flexibility to the coating film. It is also possible to use other compounds having isocyanate groups together with the NCO-containing polymer. For example, isocyanate group-containing polymers obtained by polymerizing isocyanate group-containing vinyl monomers and other copolymerizable monomers without using polyisocyanate compounds or polyfluoroalkyl group-containing vinyl monomers commonly used in polyurethane paints. and so on. However, if they are used in large quantities, they will not only deteriorate the surface properties of the coating film but also cause a decrease in weather resistance, so it is preferable not to use them unless a small amount of a compound with particularly high weather resistance is used. . As the solvent, various solvents that can dissolve the above two components are used. However, the solvent used does not have a functional group that reacts with a hydroxyl group or an isocyanate group. For example, aromatic hydrocarbons such as xylene and toluene, esters such as butyl acetate, ketones such as methyl isobutyl ketone,
Glycol ethers such as ethyl cellosolve can be used. In many cases, a urethanization catalyst is essential as an additive. As this catalyst, various known catalysts such as organometallic compounds and tertiary amines can be used, but organotin compounds such as dibutyltin dilaurate are particularly preferred. Various other additives can be optionally added, such as pigments, fillers, dispersion stabilizers, viscosity modifiers,
Leveling agents, anti-gelling agents, ultraviolet absorbers, light stabilizers, moisture absorbers, etc. may be added. The coating composition of the present invention is useful as a two-component coating composition, which is separated into two components, a component containing an NCO-containing polymer and a component containing an active hydrogen compound, and mixed together at the time of use. This type of coating composition can be cured at room temperature, but can also be cured by heating. Furthermore, by using an NCO-containing polymer with blocked isocyanate groups as described above, a one-component coating composition can be obtained; in this case,
It is usually cured by heating. Of course, other types of coating compositions are also possible, and the present invention is not limited to these two types. The composition of the present invention is not limited to metals such as iron, aluminum, copper, or alloys thereof (for example, stainless steel, brass), but also inorganic materials such as glass, cement, concrete, FRP, polyethylene, Polypropylene, ethylene-vinyl acetate copolymer, polyamide, polyacrylic, polyester, ethylene-polyvinyl alcohol copolymer,
It is applicable to various base materials such as plastics such as vinyl chloride resin, vinylidene chloride resin, polycarbonate and polyurethane, organic materials such as wood and fibers, and various base materials having a coating layer. In addition, the shape of the base material is not limited to a flat plate, and complex-shaped base materials can also be easily constructed. Furthermore, since it can be constructed on-site, it can of course be applied to large structures. It goes without saying that other than the above, appropriate additions and changes can be made as long as they do not impair the purpose and spirit of the present invention. For example, the substrate to which the composition of the present invention is applied may be subjected to appropriate pretreatment or surface treatment, or the composition of the present invention may be applied after appropriately undercoating or precoating. Synthesis examples and examples of polymers used in the examples are shown below, but the present invention is not limited to these. Synthesis Example 1 Synthesis of a polymer using isocyanate groups and polyfluoroalkyl groups Monomers having the monomer composition ratio shown in Table 1 below were mixed with a polymerization initiator (azobisisobutyronitrile) and a chain transfer agent ( 1-dodecanethiol) for 3 to 6 hours to obtain the following polymers A-1 to A-4. For comparison, polymers C-1 to C-2 without polyfluoroalkyl groups were obtained in the same manner. Number average molecular weight (Mn), number average molecular weight per isocyanate group (Mn/NCO) and number average molecular weight per polyfluoroalkyl group (Mn/FA) are shown.

[Table] Synthesis Example 2 Synthesis of hydroxyl group-containing fluorine-containing polymer According to the method described in JP-A-57-34107,
Polymer B-1 having the monomer composition ratio shown in Table 2 below
and B-2 were produced. Number average molecular weight (Mn)
and intrinsic viscosity (viscosity measured at 30°C in tetrahydrofuran).

【table】

[Table] Examples 1 to 6, Comparative Examples 1 to 6 Coating compositions shown in Table 3 were produced using a polymer having an isocyanate group and a polyfluoroalkyl group and a fluorine-containing polymer containing a hydroxyl group. For 100 parts by weight of hydroxyl group-containing fluorine-containing polymer, 0.03 parts by weight of catalyst (dibutyltin dilaurate), 40 parts by weight of pigment (titanium white), 100 parts by weight of solvent (mixture of xylene/methyl isobutyl ketone = 1:1 solubility ratio) A polymer having an isocyanate group and a polyfluoroalkyl group (the amount used is
(listed in the table) was added. As a comparative example, a general-purpose curing agent, trimerized modified hexamethylene diisocyanate (trade name "Coronate EH", manufactured by Nippon Polyurethane Co., Ltd.) was used instead of a polymer having an isocyanate group and a polyfluoroalkyl group, and C. Examples using -1 to C-3 are also shown in Table 4. The respective formulations shown in Tables 3 and 4 below were applied to the chromate-treated surface of a 0.8 mm thick aluminum plate (“5052-H34” manufactured by Mitsubishi Aluminum Corporation).
Apply so that the coating film thickness is 20μ, 120~210
Bake hardening was carried out for 5-10 minutes at a temperature of .degree. The physical properties of the cured coating film obtained are shown in Tables 3 and 4 below. The physical properties of the coating film were measured by the following method. Contact angle: The water contact angle of the coating film after curing and after the following stain resistance test was measured. Stain resistance: Evaluated by gloss retention after washing with water after one month of outdoor exposure. ◎: Retention rate 90% or more △: Retention rate 80% or more ×: Retention rate 70% or less Weather resistance: Sunshine Weather-O-Meter
The gloss retention rate after 4000 hours was evaluated. ◎ means retention rate of 95% or more 〇 means retention rate of 90% or more × means retention rate of 80% or less

【table】

[Table] Examples 9 to 14, Comparative Examples 7 to 10 In place of B-1 and B-2 in Examples 1 to 8 and Comparative Examples 1 to 6, acrylic polyol (trade name "Acrydik A-801: Dainippon Table 5 shows the results of a similar test using Ink Kagaku Kogyo Co., Ltd.).The evaluation of stain resistance and weather resistance is as follows.Stain resistance: Outdoor exposure for 1 month It was evaluated by the gloss retention rate after washing with water. ◎ indicates retention rate of 80% or more △ indicates retention rate of 70% or more × indicates retention rate of 60% or less Weather resistance: Gloss after 1000 hours on Sunshine Weather-O-meter The evaluation was based on the retention rate. 〇 means retention rate of 70% or more △ means retention rate of 60% or more × means retention rate of 50% or less

【table】

〔Effect of the invention〕

The coating film obtained using the coating composition of the present invention has excellent surface properties such as water and oil repellency and stain resistance, and has the effect that these properties are maintained over a long period of time. Moreover, the weather resistance of the coating film is good, and by using it in combination with a fluorine-containing polymer containing hydroxyl groups, which has particularly good weather resistance, the weather resistance can be further improved. It was possible to provide the above-mentioned surface properties that were not previously available.

Claims (1)

[Scope of Claims] 1. A coating composition containing a polymer and a compound having a weight ratio of 2 to 98/2 to 98. The copolymerization ratio of below is / in molar ratio.
/=5-98/2-80/0-90 Isocyanate group-containing vinyl monomer Polyfluoroalkyl group has 3 to 3 carbon atoms
A vinyl monomer containing a polyfluoroalkyl group of 20 Copolymerizable monomers other than the above Compound 2 having a functional group capable of bonding with an isocyanate group The vinyl monomer of Compound 2 is a methacrylate or acrylate having an isocyanate alkyl group. A composition according to claim 1. The composition according to claim 1, wherein the vinyl monomer (3) is a methacrylate or acrylate having a polyfluoroalkyl group having 3 to 20 carbon atoms. 4. The composition according to claim 1, wherein the vinyl monomer is a compound represented by the following formula []. R _f −X−OCOC(R ¹ )=CH ₂ …[] where R _f : perfluoroalkyl group having 3 to 16 carbon atoms X : −R ² −, −CON(R ³ )−Q
-, or _-SO2N ( ^R3 )-Q- ^R2 : Alkylene group, ^R2 : Alkyl group, Q: Alkylene group ^R1 : Hydrogen atom or methyl group 5 Compound having two or more alcoholic hydroxyl groups The composition according to claim 1, characterized in that: 6. The composition according to claim 5, wherein the compound having two or more alcoholic hydroxyl groups is a hydroxyl group-containing fluorine-containing polymer. 7. The composition according to claim 6, wherein the hydroxyl group-containing fluorine-containing polymer is a copolymer of at least three monomers: polyhaloolefin, hydroxyl group-containing vinyl ether, and vinyl ether having no hydroxyl group. .