JP7227686B2 - UV absorber resistant polyurethane composition, coating material using said composition - Google Patents

Description

Electronic device parts such as mobile phones and communication tablets, and home appliance parts. The present invention relates to an ultraviolet absorber-resistant polyurethane composition useful for daily necessities and automobile members, particularly plastic members, molded articles using the composition, and coating materials.

A polyurethane resin is obtained by reacting a polyisocyanate component and a polyol component, and polyurethane resins having various performances are provided depending on the type and combination of each component. In particular, moldings and coating materials using such resins are widely used in electronic device parts and supplies, furniture and home appliance applications, daily miscellaneous goods applications, and automobile parts applications. However, when such moldings and coating materials are used in contact with the human body for a long period of time, sebum components contained in sweat, oleic acid contained in skin protection creams, or sunscreen agents (e.g., creams, lotions, etc.) ), the surface of the molded article or coating agent deteriorates or becomes tacky, resulting in the problem that it cannot withstand long-term use.

Against this background, development of polyurethane-based resins exhibiting oil resistance to oleic acid, which is the main component of sebum, is underway. Polyurethane-based resins having excellent oleic acid resistance include polycarbonate diols using polyisocyanate compounds and 1,5-pentanediol and 1,6-hexanediol in arbitrary composition ratios, and polysiloxane as essential components. Curable compositions have been proposed (see, for example, Patent Documents 1 to 4).

However, the curable compositions described in these patent documents are not satisfactory in terms of resistance to ultraviolet absorbers contained in sunscreen agents.

In other words, the durability of conventional polyurethane-based resin coating materials against oil components such as oleic acid and beef tallow has been improved, but the durability against UV absorbers contained in cosmetics and sunscreen agents (creams, lotions, etc.) has improved. The durability is often insufficient, and adhesion of the ultraviolet absorber may cause appearance deterioration of the surface of the molded product. Therefore, there is a demand for plastic paints that are resistant to UV absorbers.

Japanese Patent Application Laid-Open No. 2007-112986 JP 2008-063395 A JP 2008-075048 A JP 2008-303284 A

The present invention has been made based on the above circumstances, and an object of the present invention is to provide a polyurethane composition having excellent durability against ultraviolet absorbers contained in cosmetics, sunscreens, etc. It is to provide a coating material and a coating film using the composition.

That is, the present invention includes the following embodiments [1] to [10].

[1] A UV-resistant prepolymer having an isocyanurate ring structure, which is a reaction product of a polyisocyanate (A), a diol (B), a polyol (C), and an aminoalcohol (D), and a curing agent. The absorbent polyurethane composition is characterized in that the diol (B) is a monomer having a molecular weight of 60 to 350, and the polyol (C) is a polymer having a molecular weight distribution of a number average molecular weight of 250 to 50,000. UV absorber resistant polyurethane composition.

[2] The UV absorber-resistant polyurethane composition of [1] above, wherein the polyisocyanate (A) has an isocyanurate ring structure.

[3] The UV absorber-resistant polyurethane according to [1] or [2] above, wherein the isocyanate source of the polyisocyanate (A) is selected from the group consisting of aliphatic isocyanates and alicyclic isocyanates. Composition.

[4] The isocyanurate ring structure of the hydroxyl-terminated prepolymer having an isocyanurate ring structure is derived from a trimer of isophorone diisocyanate. A UV absorbent polyurethane composition.

[5] The UV absorber-resistant polyurethane according to any one of [1] to [4] above, wherein the hydroxyl group-terminated prepolymer having an isocyanurate ring structure has an average number of functional groups of 2 to 11. Composition.

[6] The ultraviolet light according to any one of [1] to [5] above, wherein the polyol (C) component is less than 50% by mass in the non-volatile content of the ultraviolet absorbent resistant polyurethane composition. An absorbent polyurethane composition.

[7] The UV-resistant absorbent according to any one of [1] to [6] above, wherein at least one selected from the group consisting of aliphatic isocyanates and alicyclic isocyanates is used as the curing agent. agent polyurethane composition.

[8] Any one of [1] to [6] above, wherein at least one selected from the group consisting of an isocyanurate of hexamethylene diisocyanate and an adduct of hexamethylene diisocyanate is used as the curing agent. A UV absorber resistant polyurethane composition as described.

[9] A coating material comprising the UV absorber-resistant polyurethane composition according to any one of [1] to [8] above.

[10] A coating film comprising the ultraviolet absorber-resistant polyurethane composition according to any one of [1] to [8] above.

Since the UV absorber-resistant polyurethane composition of the present invention is excellent in durability against UV absorbers contained in cosmetics, sunscreens, etc., it can be used, for example, as a coating material for plastic members, making cosmetics and sunscreens effective. The member can be endowed with durability against an ultraviolet absorber contained in, for example. Furthermore, the hydroxyl group-terminated prepolymer of the present invention has excellent compatibility with curing agents and adhesion to plastic substrates such as ABS and PET.

The present invention will be described in detail below.

The ultraviolet absorber-resistant polyurethane composition of the present invention is characterized by containing a hydroxyl group-terminated prepolymer having an isocyanurate ring structure and a curing agent.

Here, the ultraviolet absorber used as an indicator of the resistance to ultraviolet absorbers, which is cited as the effect of the present invention, will be described. UV absorbers include para-aminobenzoic acid, cinnamic acid, benzophenone, salicylic acid, benzoyltriazole, other aromatic UV absorbers, and mixtures of one or more of these. Phenomena such as appearance deterioration and tackiness on the surface of the molded article are observed when it is transferred to the molded article or the polyurethane-based coating material. As sunscreen agents with a particularly strong tendency to this effect, those containing 3% by mass or more of salicylic acid-based ultraviolet absorbers, those containing 2% by weight or more of benzophenone-based ultraviolet absorbers, and those containing both of these are known. ing.

As shown in the examples below, the UV absorber-resistant polyurethane composition of the present invention contains at least 2-hydroxy-4-methoxybenzophenone, 2-ethylhexyl salicylate, and 3,3,5 salicylate among these UV absorbers. -trimethylcyclohexyl, 2-ethylhexyl 3,3-diphenyl-2-cyanoacrylate, 2-ethylhexyl-4-methoxycinnamate, and 4-tert-butylbenzoyl(4-methoxybenzoyl)methane indicates

Next, the hydroxyl group-terminated prepolymer used in the ultraviolet absorber resistant polyurethane composition of the present invention will be explained.

The hydroxyl-terminated prepolymer of the present invention is a reaction product of polyisocyanate (A), diol (B), polyol (C) and aminoalcohol (D). The isocyanurate ring structure of the hydroxyl-terminated prepolymer is derived from the polyisocyanate (A), the diol (B), the polyol (C), or the amino alcohol (D). However, it is preferable to use a polyisocyanate having an isocyanurate ring structure because of its easy availability.

The isocyanate source of the polyisocyanate (A) is not particularly limited, but examples thereof include aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and araliphatic diisocyanates. Of these, aliphatic diisocyanates and alicyclic diisocyanates are preferred from the viewpoint of coating film weather resistance and UV absorber resistance. Moreover, from the viewpoint of solvent solubility and drying property, alicyclic diisocyanates are more preferable, and isophorone diisocyanate is particularly preferable.

For these reasons, it is most preferable to use a trimer of isophorone diisocyanate as the polyisocyanate having an isocyanurate ring structure.

<Aliphatic Diisocyanate>
Specific examples of aliphatic diisocyanates include hexamethylene diisocyanate, tetramethylene diisocyanate, 2-methyl-pentane-1,5-diisocyanate, 3-methyl-pentane-1,5-diisocyanate, lysine diisocyanate, and trioxyethylene diisocyanate. etc., and mixtures thereof can also be used.

<Alicyclic diisocyanate>
Specific examples of the alicyclic diisocyanate include isophorone diisocyanate, cyclohexane diisocyanate, hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, and hydrogenated tetramethylxylene diisocyanate. Mixtures of these can also be used. Among these alicyclic diisocyanates, isophorone diisocyanate (hereinafter referred to as "IPDI") is particularly preferred from the viewpoint of UV absorber resistance and productivity.

<Aromatic diisocyanate>
Specific examples of aromatic diisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, and 2,2'-diphenylmethane diisocyanate. , 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate , 4,4'-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate etc., and mixtures thereof can also be used.

<Aroliphatic Diisocyanate>
Specific examples of araliphatic diisocyanates include 1,3- or 1,4-xylylene diisocyanate, 1,3- or 1,4-bis(1-isocyanato-1-methylethyl)benzene, ω,ω' -diisocyanato-1,4-diethylbenzene and the like, and mixtures thereof can also be used.

Further, within the scope of the present invention, for example, the above aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, araliphatic diisocyanate, or isocyanurate group-containing polyisocyanate made from these polyisocyanates, Uretdione group-containing polyisocyanates, uretdione group- and isocyanurate group-containing polyisocyanates, urethane group-containing polyisocyanates, allophanate group-containing polyisocyanates, buret group-containing polyisocyanates, uretimine group-containing polyisocyanates, and the like can also be used in combination.

<Diol>
The diol (B) is not particularly limited, but is a monomer having a molecular weight of 60 to 350 and a monomer having a molecular weight of 60 to 250 from the viewpoint of solvent solubility of the hydroxyl-terminated prepolymer, curing agent compatibility, and UV absorber resistance. Monomers are preferred.

Specific examples of such diol (B) include ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, and isomers thereof. In addition, diethylene glycol, triethylene glycol, cyclohexanediol, cyclohexanedimethanol, 4,4'-bicyclohexanol, 1,3-adamantanediol, dimethylolpropionic acid, dimethylolbutanoic acid, etc. are used alone, or two or more of them are used. Can be used in combination.

In addition, a hydroxyl group-terminated compound capable of reacting with isocyanate, such as polyalkylene glycol, fluorine-containing diol, and silicon-containing diol, can be used in combination without departing from the scope of the present invention.

The content of the diol (B) is preferably 0.1% by mass to 15% by mass in the nonvolatile matter of the hydroxyl-terminated prepolymer. Within this range, it is possible to obtain a hydroxyl group-terminated prepolymer that is excellent in solvent solubility as well as UV absorber resistance.

<Polyol>
The polyol (C) is not particularly limited, and examples thereof include polycarbonate polyols, polycaprolactone polyols, polyester polyols, polyether polyols, polyolefin polyols, acrylic polyols, silicone polyols, castor oil-based polyols, and fluorine-based polyols. It can be used alone or in combination of two or more.

Polyol (C) in the present invention is a polymer having a molecular weight distribution, excluding diol (B). The polyol (C) has a number average molecular weight of 250 to 50,000, preferably 300 to 4,000, more preferably 350 to 4,000. If the number-average molecular weight is less than the lower limit, the adhesiveness to the plastic substrate may be reduced, and if it exceeds the upper limit, the solvent solubility may be reduced.

The content of the polyol (C) is preferably less than 50% by mass in the non-volatile content of the UV absorbent resistant polyurethane composition. When the amount is less than 50% by mass, both the adhesion of the coating film to the plastic substrate and the resistance to ultraviolet absorbers can be achieved. In addition, the non-volatile matter in this invention is a component except an organic solvent.

Further, the polyol (C) preferably has 1.9 or more active hydrogen groups (average number of functional groups) per molecule. If the number of active hydrogen groups is less than 1.9, the UV absorber resistance and mechanical properties may deteriorate.

<Polycarbonate polyol>
Specific examples of polycarbonate polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1, 5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol , neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide and propylene oxide adducts of bisphenol A, bis(β-hydroxyethyl)benzene, xylylene glycol, One or more of low-molecular-weight polyhydric alcohols such as glycerin, trimethylolpropane, and pentaerythritol, dialkyl carbonates such as dimethyl carbonate and diethyl carbonate, alkylene carbonates such as ethylene carbonate and propylene carbonate, diphenyl carbonate, dinaphthyl carbonate, Those obtained from dealcoholization reaction and dephenolation reaction with diaryl carbonates such as dianthryl carbonate, diphenanthryl carbonate, diindanyl carbonate, tetrahydronaphthyl carbonate and the like can be mentioned. Also, from the viewpoint of imparting wear resistance, scratch resistance, and resistance to oleic acid, a polycarbonate polyol composed of 1,6-hexanediol and diethyl carbonate can be preferably used.

<Polycaprolactone polyol>
Specific examples of polycaprolactone polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1 ,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene Glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide and propylene oxide adducts of bisphenol A, bis(β-hydroxyethyl)benzene, xylylene glycol , glycerin, trimethylolpropane, pentaerythritol, etc., as an initiator, and either one or both of ε-caprolactone and alkyl-substituted ε-caprolactone are used to carry out ring-opening addition. be able to.

<Polyester polyol>
Specific examples of polyester polyols include phthalic acid, isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, glutaconic acid, and azelaine. acid, sebacic acid, 1,4-cyclohexyldicarboxylic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α,β-diethylsuccinic acid, maleic acid, fumaric acid, etc. Dicarboxylic acid or one or more of these anhydrides, and ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butane Diol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol , dipropylene glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide and propylene oxide adducts of bisphenol A, bis(β-hydroxyethyl)benzene, Examples include those obtained from a polycondensation reaction with one or more low-molecular-weight polyols having a molecular weight of 500 or less, such as xylylene glycol, glycerin, trimethylolpropane, and pentaerythritol. Polyester-amide polyols obtained by replacing part of the low-molecular-weight polyol with low-molecular-weight polyamines such as hexamethylenediamine, isophoronediamine and monoethanolamine or low-molecular-weight aminoalcohols can also be used.

<Polyether polyol>
Specific examples of polyether polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1 ,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene Glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A, bis(β-hydroxyethyl)benzene, xylylene glycol, glycerin, trimethylolpropane, penta Two or more, preferably 2 to 3, active hydrogen groups such as low-molecular-weight polyols such as erythritol, or low-molecular-weight polyamines such as ethylenediamine, propylenediamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, and xylylenediamine Polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, etc., using a unique compound as an initiator, or alkyl glycidyl ethers such as methyl glycidyl ether, phenyl glycidyl ether, etc. aryl glycidyl ethers and polyether polyols obtained by ring-opening polymerization of cyclic ether monomers such as tetrahydrofuran.

<Polyolefin polyol>
Specific examples of polyolefin polyols include polybutadiene having two or more hydroxyl groups, hydrogenated polybutadiene, polyisoprene, and hydrogenated polyisoprene.

<Acrylic polyol>
Examples of acrylic polyols include acrylic acid esters and/or methacrylic acid esters (hereinafter referred to as (meth)acrylic acid esters), acrylic acid hydroxy compounds having at least one or more hydroxyl groups in the molecule that can serve as reaction sites, and/or A methacrylic acid hydroxy compound [hereinafter referred to as a (meth)acrylic acid hydroxy compound] and a polymerization initiator are copolymerized using thermal energy, light energy such as ultraviolet rays or electron beams, and acrylic monomers. .

<(Meth) acrylic acid ester>
Specific examples of (meth)acrylic acid esters include alkyl esters having 1 to 20 carbon atoms. Specific examples of such (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, (Meth)acrylates such as hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate and dodecyl (meth)acrylate acrylic acid alkyl esters; esters of (meth)acrylic acid with alicyclic alcohols such as cyclohexyl (meth)acrylate; (meth)acrylic acid aryl esters such as phenyl (meth)acrylate and benzyl (meth)acrylate can be mentioned. Such (meth)acrylic acid esters may be used alone or in combination of two or more.

<(Meth)acrylic acid hydroxy compound>
Specific examples of (meth)acrylic acid hydroxy compounds include at least one hydroxyl group in the molecule that can be a reaction point with polyisocyanate. Examples include hydroxy acrylate compounds such as hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 3-hydroxy-2,2-dimethylpropyl acrylate, and pentaerythritol triacrylate. Also included are hydroxy methacrylate compounds such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 3-hydroxy-2,2-dimethylpropyl methacrylate and pentaerythritol trimethacrylate. These acrylic acid hydroxy compounds and methacrylic acid hydroxy compounds can be used alone or in combination of two or more.

<Silicone polyol>
Specific examples of silicone polyols include, for example, vinyl group-containing silicone compounds obtained by polymerizing γ-methacryloxypropyltrimethoxysilane, and α,ω-dihydroxypolydimethylsiloxane having at least one terminal hydroxyl group in the molecule, Polysiloxanes such as α,ω-dihydroxypolydiphenylsiloxanes may be mentioned.

<Castor oil-based polyol>
Specific examples of castor oil-based polyols include, for example, linear or branched polyester polyols obtained by reacting castor oil fatty acids with polyols. Dehydrated castor oil, partially dehydrated castor oil, and hydrogenated castor oil to which hydrogen is added can also be used.

<Fluorinated polyol>
A specific example of the fluorine-based polyol is a linear or branched polyol obtained by a copolymerization reaction of a fluorine-containing monomer and a monomer having a hydroxyl group as essential components. Here, the fluorine-containing monomer is preferably a fluoroolefin such as tetrafluoroethylene, chlorotrifluoroethylene, trichlorofluoroethylene, hexafluoropropylene, vinylidene fluoride, vinyl fluoride, trifluoromethyltrifluoroethylene. is mentioned. Examples of monomers having a hydroxyl group include hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and cyclohexanediol monovinyl ether, hydroxyalkyl allyl ethers such as 2-hydroxyethyl allyl ether, and vinyl hydroxyalkyl crotonates. and monomers having a hydroxyl group such as a hydroxyl group-containing vinyl carboxylate or allyl ester.

<Amino alcohol>
The amino alcohol (D) is not particularly limited as long as it is a compound having an amino group and a hydroxyl group. Those having one amino group or secondary amino group and 1 to 3 hydroxyl groups are preferred.

Specific examples of such amino alcohols (D) include 2-aminoethanol, 2-(methylamino)ethanol, 2-amino-2-methyl-1-propanol, 1-amino-2-propanol, 2 -amino-1-propanol, 1-amino-2-methyl-2-propanol, 2-(ethylamino)ethanol, 2-(tert-butylamino)ethanol, 2-(propylamino)ethanol, 2-(isopropylamino ) ethanol, 2-amino-1-butanol, 1-amino-2-butanol, 4-(methylamino)-1-butanol, 2-amino-3,3-dimethylbutanol, 2-amino-3-methyl-1 -butanol, 2-(butylamino)ethanol, 2-hydroxyisobutyramide, 2-hydroxypropionamide, 2-amino-4-methyl-1-pentanol, 3-amino-1-propanol, 5-amino-1- Pentanol, 6-amino-1-hexanol, 2-amino-3-hydroxypropionic acid, 3-amino-2,2-dimethyl-1-propanol, 4-amino-1-butanol, 8-amino-1-octanol , 10-amino-1-decanol, 2-isopropylamino-3-methyl-1-butanol, 12-amino-1-dodecanol, 2-(cyclohexylamino)ethanol, 2-aminocyclohexanol, 4-amino-2- Methyl-1-butanol, 3-(methylamino)-1-propanol, 2-piperidinemethanol, 3-piperidinemethanol, 4-piperidinemethanol, 3-hydroxypiperidine, 4-hydroxypiperidine, 2-piperidineethanol, 4-piperidine ethanol, 2-pyrrolidinemethanol, 2-(4-piperidyl)-2-propanol, 4-hydroxy-2,2,6,6-tetramethylpiperidine, nortropine, 1-[2-(2-hydroxyethoxy)ethyl] Piperazine, 1-piperazineethanol, diethanolamine, 2-amino-1,3-propanediol, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 2-amino- 2-ethyl-1,3-propanediol, diisopropanolamine, 2-[(hydroxymethyl)amino]ethanol, N-(3-aminopropyl)diethanolamine, 3-methylamino-1,2-propanediol, 3- tert-butylamino -1,2-propanediol, tris(hydroxymethyl)aminomethane, N-[tris(hydroxymethyl)methyl]glycine and the like.

The hydroxyl group-terminated prepolymer used in the UV-resistant polyurethane composition of the present invention may contain a monol in combination with the diol (B) without departing from the spirit of the present invention.

Although the monool is not particularly limited, an alkyl alcohol having 1 to 20 carbon atoms is preferable from the viewpoint of the solvent solubility of the hydroxyl group-terminated prepolymer, the compatibility with the curing agent, and the resistance to the ultraviolet absorber.

Specific examples of such monools include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1- Pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2,2-dimethyl-1-propanol, 1-hexanol, 2-hexanol, 2-methyl -1-pentanol, 2-ethyl-2-butanol, 1-heptanol, 1-octanol, 2-ethyl-1-hexanol, 1-nonanol, 2-nonanol, 3,5,5-trimethyl-1-hexanol, 1-decanol, isodecanol, 1-undecanol, 2-undecanol, 1-dodecanol, 1-tridecanol, isotridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-heptadecanol , 1-octadecanol, 1-nonadecanol, 1-eicosanol and the like.

In addition, a hydroxyl group-terminated compound capable of reacting with isocyanate, such as benzyl alcohol, methoxypolyethylene glycol, and fluoroalcohols, can be used in combination without departing from the scope of the present invention.

Next, a general method for producing the hydroxyl group-terminated prepolymer constituting the ultraviolet absorber resistant polyurethane composition of the present invention will be described. However, the method for producing the hydroxyl-terminated prepolymer is not limited to this.

<Method for producing hydroxyl-terminated prepolymer>
In the presence or absence of an organic solvent, the polyisocyanate (A), the diol (B) and the polyol (C) are mixed in a molar ratio (R) of the isocyanate group to the hydroxyl group, preferably R=isocyanate group/hydroxyl group. An amount of 1.5 to 50 is charged, and the polyisocyanate-modified product is produced by urethanization reaction preferably at 60° C. or higher.

The obtained polyisocyanate modified product and the amino alcohol (D) are added in an amount such that the molar ratio (R) of the isocyanate group to the amino group is preferably 0.7 to 1.3 where R = isocyanate group / amino group. and preferably urea-reacted at 80° C. or lower to produce a hydroxyl group-terminated prepolymer.

Moreover, in a series of production steps, it is preferable to proceed the reaction under nitrogen gas or dry air stream in order to suppress the reaction between the isocyanate group and moisture.

Further, the reaction temperature for the urea formation reaction is preferably 80°C or lower, more preferably 60°C or lower. The lower limit of the reaction temperature is not particularly limited as long as it is a temperature at which the reaction solution does not solidify. By setting the reaction temperature to 80 ° C. or less, the hydroxyl group derived from the amino alcohol (D) that has undergone a urea reaction with the polyisocyanate modified product (reaction product of polyisocyanate (A), diol (B) and polyol (C)) Then, the isocyanate groups remaining in the reaction system cause a urethanization reaction, which can suppress the formation of aggregates and the insolubilization of the entire system.

The hydroxyl group-terminated prepolymer thus obtained preferably has 2 to 11 functional groups, more preferably 3 to 10 functional groups.

Moreover, the organic solvent used for producing the hydroxyl group-terminated prepolymer is not particularly limited as long as it does not affect the reaction in the presence of the organic solvent.

<Organic solvent used for manufacturing>
Specific examples of such organic solvents include aliphatic hydrocarbons such as octane, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ethyl acetate, Esters such as butyl acetate and isobutyl acetate, glycol ether esters such as ethylene glycol ethyl ether acetate, propylene glycol monomethyl ether acetate, 3-methyl-3-methoxybutyl acetate and ethyl-3-ethoxypropionate, dioxane and the like Halogenated hydrocarbons such as ethers, methylene iodide and monochlorobenzene, polar aprotic solvents such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and hexamethylphosphonylamide, and tertiary solvents such as diacetone alcohol. class alcohols and the like. These solvents can be used alone or in combination of two or more.

Alcohols such as ethanol and isopropanol can also be used as long as the performance does not deteriorate.

Next, the curing agent that constitutes the UV-resistant polyurethane composition of the present invention will be described.

Examples of curing agents include polyisocyanates, and from the viewpoint of coating film weather resistance, aliphatic polyisocyanates, alicyclic polyisocyanates, and polyisocyanates in which these are combined are preferred. As a curing agent, from the viewpoint of compatibility with hydroxyl group-terminated prepolymers and organic solvents and weather resistance, an isocyanurate form of hexamethylene diisocyanate (hereinafter referred to as "HDI") or an adduct obtained by partially modifying HDI with urethane is used. Body is particularly preferred.

Further, the curing agent includes, within the scope of the present invention, for example, the above aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate, araliphatic diisocyanate, or uretdione obtained from these polyisocyanates. Group-containing polyisocyanate, uretdione group- and isocyanurate group-containing polyisocyanate, urethane group-containing polyisocyanate, allophanate group-containing polyisocyanate, burette group-containing polyisocyanate, uretimine group-containing polyisocyanate, etc., alone or in combination of two or more can also be used.

The UV absorber-resistant polyurethane composition of the present invention may optionally contain, for example, antioxidants, UV absorbers, pigments, dyes, flame retardants, hydrolysis inhibitors, lubricants, plasticizers, fillers, Additives such as antistatic agents, dispersants, catalysts, storage stabilizers, surfactants and leveling agents can be added as appropriate.

Next, a method for processing a molded article and a coating material using the ultraviolet absorber resistant polyurethane composition of the present invention will be described.

The ultraviolet absorber-resistant polyurethane composition of the present invention is used, for example, as moldings or coating materials for electronic device members such as communication tablets, furniture/household appliance members, daily necessities, automobile members, and the like.

Molded bodies include, for example, members, structures, films, and sheets, which are molded by known techniques such as casting and coating.

Further, when the UV-resistant polyurethane composition of the present invention is used as a coating material, for example, the resin composition for a coating material containing the above-described hydroxyl-terminated prepolymer is added with the above-described curing agent and, if necessary, After mixing the above additives and uniformly stirring, a coating film is formed on the substrate by known techniques such as spray coating, knife coating, wire bar coating, doctor blade coating, reverse roll coating, calendar coating, etc. do.

Examples of the base material include acrylic resin, polycarbonate resin, polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene phthalate resin, polystyrene resin, AS resin, ABS resin, polycarbonate-ABS resin, 6-nylon resin, 6, 6-nylon resin, MXD6 nylon resin, polyvinyl chloride resin, polyvinyl alcohol resin, polyurethane resin, phenolic resin, melamine resin, polyacetal resin, chlorinated polyolefin resin, polyolefin resin, polyamide resin, polyether ether ketone resin, polyphenylene sulfide resin , NBR resin, chloroprene resin, SBR resin, SEBS resin, and olefin resins such as polyethylene and polypropylene.

These substrates may be previously treated with corona discharge treatment, flame treatment, ultraviolet irradiation treatment, ozone treatment, primer treatment, solvent treatment, etc. in order to improve adhesiveness.

The amount of the coating material to be applied is not particularly limited, but it is preferable to apply the coating material so that the dry film thickness is 20 μm or more, for example. By setting the film thickness to 20 μm or more, the UV absorber resistance of the coating material can be improved.

Next, when the UV-resistant polyurethane composition of the present invention is used as a coating solution, the coating solution should contain the hydroxyl groups of the hydroxyl-terminated prepolymer and the isocyanate groups of the polyisocyanate used as the curing agent. The ratio (R) is R = isocyanate group/hydroxyl group, and is preferably blended so that R = 0.4 to 2.5, more preferably R = 0.7 to 1.5. preferably. The organic solvent used for dilution is not particularly limited, but may be used alone or in combination of two or more of the above <organic solvents used in production>.

Examples of the present invention will be described below, but the present invention should not be construed as being limited to these examples.

<Synthesis of hydroxyl-terminated prepolymer>
<Production Example 1>
IPDI isocyanurate (manufactured by Evonik, trade name: VESTANAT T1890/100, NCO content 17.0%) was placed in a 1-liter four-necked flask equipped with a stirrer, a thermometer, a heating device, and a distillation column. 3% by mass, hereinafter referred to as "IPDI nurate"), 53 g of IPDI, and 450 g of methyl ethyl ketone (hereinafter referred to as "MEK") were charged, and these were uniformly stirred at 25 ° C. with nitrogen gas bubbling. A polyisocyanate solution was prepared. To this polyisocyanate solution, 10 g of ethylene glycol (manufactured by Kishida Chemical Co., Ltd.) as diol (B) and polyol 1 (1,6-hexanediol-based polycarbonate polyol, number average molecular weight 1,000, number of functional groups 2) as polyol (C). A 124 g portion was charged, and a urethanization reaction was carried out at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified product is cooled to room temperature, 100 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is performed under a nitrogen stream while maintaining the temperature at 60 ° C. or less to form hydroxyl groups. A terminal prepolymer solution PP-1 was obtained. The hydroxyl value of this prepolymer was 107 KOHmg/g.

<Production Example 2>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 257 g of IPDI nurate, 52 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 1,4-butanediol (manufactured by Kishida Chemical Co., Ltd.) as a diol (B) and 121 g of polyol 1 as a polyol (C) are charged, and a urethanization reaction is performed at 75 ° C. under a nitrogen stream to obtain a polyol. An isocyanate modified product was obtained. The resulting polyisocyanate-modified solution is cooled to room temperature, 110 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-2 was obtained. The hydroxyl value of this prepolymer was 116 KOHmg/g.

<Production Example 3>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 251 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and 124 g of polyol 1 as polyol (C) were charged, and urethane was dissolved at 75° C. under a nitrogen stream. A polyisocyanate-modified product was obtained by carrying out a chemical reaction. The resulting polyisocyanate-modified solution is cooled to room temperature, 115 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-3 was obtained. The hydroxyl value of this prepolymer was 122 KOHmg/g.

<Production Example 4>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 251 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 1,9-nonanediol (manufactured by Kuraray Co., Ltd.) as diol (B) and 124 g of polyol 1 as polyol (C) were charged, and a urethanization reaction was carried out at 75° C. under a nitrogen stream to obtain polyisocyanate. A modified product was obtained. The resulting polyisocyanate-modified solution is cooled to room temperature, 115 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-4 was obtained. The hydroxyl value of this prepolymer was 122 KOHmg/g.

<Production Example 5>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 253 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of cyclohexanedimethanol (manufactured by EASTMAN CHEMICAL) as a diol (B) and 124 g of polyol 1 as a polyol (C) are charged, and a urethanization reaction is performed at 75 ° C. under a nitrogen stream to obtain a modified polyisocyanate. got The resulting polyisocyanate-modified solution is cooled to room temperature, 113 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-5 was obtained. The hydroxyl value of this prepolymer was 121 KOHmg/g.

<Production Example 6>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 253 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 12 g of dimethylolpropionic acid (manufactured by Perstorp) as a diol (B) and 124 g of polyol 1 as a polyol (C) are charged, and a urethanization reaction is performed at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. got The resulting polyisocyanate-modified solution is cooled to room temperature, 111 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-6 was obtained. The hydroxyl value of this prepolymer was 118 KOHmg/g.

<Production Example 7>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 243 g of IPDI nurate, 49 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and polyol 2 (1,6-hexanediol-based polycarbonate polyol, number 124 g of 2) having an average molecular weight of 2,000 and a functional group number of 2) was charged and subjected to a urethanization reaction at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified solution is cooled to room temperature, 124 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-7 was obtained. The hydroxyl value of this prepolymer was 131 KOHmg/g.

<Production Example 8>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 251 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and polyol 3 (1,4-butanediol/adipic acid-based polyester) as polyol (C) 124 g of a polyol having a number average molecular weight of 1,000 and a functional group of 2) was charged, and a urethanization reaction was carried out at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified solution is cooled to room temperature, 115 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-8 was obtained. The hydroxyl value of this prepolymer was 122 KOHmg/g.

<Production Example 9>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 251 g of IPDI nurate, 50 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and polyol 4 (polycaprolactone polyol, number average molecular weight of 1,000, 124 g of functional group 2) was charged and subjected to urethanization reaction at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified solution is cooled to room temperature, 115 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-9 was obtained. The hydroxyl value of this prepolymer was 122 KOHmg/g.

<Production Example 10>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 255 g of IPDI nurate, 51 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . In this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as a diol (B), 10 g of 1-propanol (manufactured by Kishida Chemical Co., Ltd.) as a monool, and 10 g of a polyol (C) 124 g of polyol 1 was charged and subjected to a urethanization reaction at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified solution is cooled to room temperature, 100 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-10 was obtained. The hydroxyl value of this prepolymer was 106 KOHmg/g.

<Production Example 11>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 256 g of IPDI nurate, 51 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of dimethylolpropionic acid (manufactured by Perstorp) as a diol (B), 11 g of 1-propanol (manufactured by Kishida Chemical Co., Ltd.) as a monool and polyol 4 (polycaprolactone polyol, number average 124 g of a compound having a molecular weight of 1,000 and a functional group number of 2) was charged, and a urethanization reaction was carried out at 75° C. under a nitrogen stream to obtain a modified polyisocyanate. The resulting polyisocyanate-modified solution is cooled to room temperature, 98 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and the urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-11 was obtained. The hydroxyl value of this prepolymer was 104 KOHmg/g.

<Production Example 12>
HDI allophanate (manufactured by Tosoh Corporation, trade name: Coronate 2770, NCO content 19.4% by mass) was added to a 1-liter four-necked flask equipped with a stirrer, a thermometer, a heating device, and a distillation column. ), 51 g of IPDI, and 450 g of MEK were charged, and these were uniformly stirred at 25° C. with nitrogen gas bubbling to prepare a polyisocyanate solution. To this polyisocyanate solution, 10 g of ethylene glycol (manufactured by Kishida Chemical Co., Ltd.) as a diol (B) and 124 g of polyol 1 as a polyol (C) are charged, and a urethanization reaction is performed at 75 ° C. under a nitrogen stream to obtain a modified polyisocyanate. Obtained. The resulting polyisocyanate-modified solution is cooled to room temperature, 110 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-12 was obtained. The hydroxyl value of this prepolymer was 117 KOHmg/g.

<Production Example 13>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 245 g of HDI allophanate, 49 g of IPDI, and 450 g of MEK as polyisocyanate (A), and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and 120 g of polyol 1 as polyol (C) were charged, and urethane was dissolved at 75° C. under a nitrogen stream. A polyisocyanate-modified product was obtained by carrying out a chemical reaction. The resulting polyisocyanate-modified solution is cooled to room temperature, 126 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) is gradually added as an amino alcohol (D), and a urea reaction is allowed to occur under a nitrogen stream while maintaining the temperature at 60° C. or less. A hydroxyl group-terminated prepolymer solution PP-13 was obtained. The hydroxyl value of this prepolymer was 134 KOHmg/g.

<Production Example 14>
379 g of HDI adduct (manufactured by Tosoh Corporation, C-HL, NCO content 12.7%) as polyisocyanate (A) was placed in a 1-liter four-necked flask equipped with a stirrer, thermometer, heating device, and distillation column. Then, 28 g of IPDI and 100 g of MEK were charged, and these were uniformly stirred at 25° C. with nitrogen gas bubbling to prepare a polyisocyanate solution. To this polyisocyanate solution, 11 g of ethylene glycol (manufactured by Kishida Chemical Co., Ltd.) as a diol (B) and 142 g of polyol 1 as a polyol (C) are charged, and a urethanization reaction is performed at 75 ° C. under a nitrogen stream to obtain a modified polyisocyanate. Obtained. The resulting polyisocyanate-modified solution was cooled to room temperature, 255 g of diacetone alcohol (hereinafter DAA) and 85 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) as an amino alcohol (D) were gradually added, and heated to 60°C or less under a nitrogen stream. A hydroxyl group-terminated prepolymer solution PP-14 was obtained by urea-forming reaction while maintaining the temperature. The hydroxyl value of this prepolymer was 105 KOHmg/g.

<Production Example 15>
A four-necked flask with a capacity of 1 liter equipped with a stirrer, a thermometer, a heating device, and a distillation column was charged with 365 g of HDI adduct as polyisocyanate (A), 27 g of IPDI, and 100 g of MEK, and these were heated to 25 ° C. A polyisocyanate solution was prepared by bubbling nitrogen gas with uniform stirring at . To this polyisocyanate solution, 10 g of 2,4-diethyl-1,5-pentanediol (manufactured by KH Neochem) as diol (B) and 136 g of polyol 1 as polyol (C) were charged, and urethane was dissolved at 75° C. under a nitrogen stream. A polyisocyanate-modified product was obtained by carrying out a chemical reaction. The resulting polyisocyanate-modified solution was cooled to room temperature, and 259 g of DAA and 103 g of diethanolamine (manufactured by Kishida Chemical Co., Ltd.) as an amino alcohol (D) were gradually added, and the urea reaction was carried out under a stream of nitrogen while maintaining the temperature at 60°C or less. Thus, a hydroxyl group-terminated prepolymer solution PP-15 was obtained. The hydroxyl value of this prepolymer was 109 KOHmg/g.

Tables 1 and 2 show the amounts and properties of the raw materials used in the hydroxyl-terminated prepolymers of PP-1 to PP-11 and PP-12 to PP-15.

<Production of coating material>
The obtained hydroxyl group-terminated prepolymers of PP-1 to PP-15, hydroxyl groups of acrylic polyol and polycarbonate diol, and polyisocyanate (HDI isocyanurate, manufactured by Tosoh Corporation, trade name: Coronate HX, NCO content 21.1% by mass, Or HDI Adduct, manufactured by Tosoh Corporation, trade name: Coronate HL, NCO content 12.7% by mass, solid content 75% by mass) so that the molar ratio with the isocyanate group is 1.0 at R = isocyanate group / hydroxyl group and further diluted with MEK or a mixed solvent of MEK and DAA so that the total solid content is 45% by mass, to prepare a paint formulation solution. This was applied to a polyethylene terephthalate plate (manufactured by Paltec) with an applicator so that the film thickness after drying was 30 μm, dried at 25° C. for 1 hour, and cured at 80° C. for 10 hours to prepare a coating material. The acrylic polyols shown in Comparative Examples 5 and 11 are Acrydic A-801 manufactured by DIC Corporation (hydroxyl value: 50 KOHmg/g, solid content: 50% by mass), and the polycarbonate diols shown in Comparative Examples 6 and 12 are: It is NIPPOLAN 970 (hydroxyl value: 224 KOHmg/g) manufactured by Tosoh Corporation.

Tables 3 to 5 show the composition of each blended solution and the physical properties of the obtained coating materials.

Abbreviations used in Tables 3 to 5 are as follows.
(1) Compound a: 2-hydroxy-4-methoxybenzophenone (2) Compound b: 2-ethylhexyl salicylate (3) Compound c: 3,3,5-trimethylcyclohexyl salicylate (4) Compound d: 3,3-diphenyl -2-Ethylhexyl cyanoacrylate (5) Compound e: 2-ethylhexyl-4-methoxycinnamate (6) Compound f: 4-tert-butylbenzoyl (4-methoxybenzoyl) methane (3% diluent in glycerin)

The evaluation results shown in Tables 3 to 5 are based on the following evaluation methods.

(1) Evaluation test 1:
<Paint film drying property>
After coating with an applicator, the dry state of the coating film dried at 25° C. for 1 hour was evaluated by finger touch.
<Evaluation Criteria>
・No stickiness on the coating film (evaluation: A)
・There is stickiness in the coating film (Evaluation: B)

(2) Evaluation test 2:
<UV absorber resistance>
0.02 g of the following compounds (1) to (5) were dropped on the coating film, left at 80° C. for 1 hour, the drops were wiped off, and the appearance was visually evaluated. Since compound (6) is a solid, it was dissolved in glycerin to a concentration of 3%, and 0.02 g of the solution was added dropwise to the coating film. .
<Compound>
(1) 2-hydroxy-4-methoxybenzophenone (2) 2-ethylhexyl salicylate (3) 3,3,5-trimethylcyclohexyl salicylate (4) 2-ethylhexyl 3,3-diphenyl-2-cyanoacrylate (5) 2-ethylhexyl-4-methoxycinnamate (6) 4-tert-butylbenzoyl (4-methoxybenzoyl) methane <Evaluation criteria>
・No change in coating film (Evaluation: A)
・Those with slight chemical traces on the coating film (Evaluation: B)
・Those in which the coating film swelled significantly and caused a change in gloss (Evaluation: C)
・ Dissolution of the coating film (evaluation: D)

As shown in Tables 3 to 5, it was found that the coating materials according to Examples 1 to 22 are excellent in resistance to UV absorbers. On the other hand, the coating materials of Comparative Examples 1 to 12 were inferior in UV absorber resistance.

Claims (9)

A hydroxyl-terminated prepolymer having an isocyanurate ring structure, which is a reaction product of a modified polyisocyanate, which is a reaction product of polyisocyanate (A) , diol (B) , and polyol (C), and an aminoalcohol (D). and a curing agent, wherein the diol (B) is a monomer having a molecular weight of 60 to 250 and is a component other than the aminoalcohol (D), and the polyol (C) is It is a polymer having a molecular weight distribution with a number average molecular weight of 300 to 4000 , and the amino alcohol (D) has one primary amino group or secondary amino group and 1 to 3 hydroxyl groups in one molecule. and wherein the curing agent is at least one selected from the group consisting of aliphatic isocyanates and alicyclic isocyanates . 2. The ultraviolet absorber resistant polyurethane composition according to claim 1, wherein the polyisocyanate (A) has an isocyanurate ring structure. 3. The ultraviolet absorber-resistant polyurethane composition according to claim 1, wherein the isocyanate source of polyisocyanate (A) is selected from the group consisting of aliphatic isocyanates and cycloaliphatic isocyanates. 4. The ultraviolet absorber-resistant polyurethane according to any one of claims 1 to 3, wherein the isocyanurate ring structure of the hydroxyl group-terminated prepolymer having an isocyanurate ring structure is derived from a trimer of isophorone diisocyanate. Composition. 5. The ultraviolet absorber-resistant polyurethane composition according to any one of claims 1 to 4, wherein the hydroxyl group-terminated prepolymer having an isocyanurate ring structure has an average functional group number of 2 to 11. 6. The UV resistant absorbent according to any one of claims 1 to 5, wherein the component derived from the polyol (C) accounts for less than 50% by mass of the non-volatile content of the UV absorbent resistant polyurethane composition. agent polyurethane composition. 7. The UV resistant absorbent according to any one of claims 1 to 6, wherein at least one selected from the group consisting of an isocyanurate of hexamethylene diisocyanate and an adduct of hexamethylene diisocyanate is used as the curing agent. agent polyurethane composition. A coating material comprising the ultraviolet absorber resistant polyurethane composition according to any one of claims 1 to 7 . A coating film comprising the ultraviolet absorber resistant polyurethane composition according to any one of claims 1 to 7 .