JP2020041013A - Reactive ultraviolet absorber, and production method, coating composition and polymer thereof - Google Patents

Abstract

To provide: a reactive ultraviolet absorber which has good reactivity with other acrylic monomers, is easy to handle, and can impart, to a polymer, weather resistance without bleedout or effluence; and a production method, a coating composition and a polymer thereof.SOLUTION: The invention provides a production method, a coating composition and a polymer of a reactive ultraviolet absorber selected from specific 2,4-dihydroxybenzophenone derivatives, 4-hydroxybenzophenone derivatives, 2-4-dihydroxy-4'-methylbenzophenone derivatives, 2-(2-4-dihydroxyphenyl)2H-benzotriazole derivatives, and 2-(2'-hydroxy-5'-(2-hydroxyethyl)phenyl)benzotriazole derivatives.SELECTED DRAWING: None

Description

  The present invention relates to a novel reactive ultraviolet absorber, and a method for producing the same, a coating composition containing the absorber, and a polymer, particularly by copolymerizing the absorber with another monomer. The present invention relates to a reactive ultraviolet absorber capable of imparting weather resistance without bleed-out or outflow to an obtained polymer and a method for producing the same.

  2. Description of the Related Art Conventionally, a large number of ultraviolet absorbers are commercially available for the purpose of improving weather resistance, and are used by being added to paints, coating agents, inks, plastic molded products, and the like. However, since these commercially available ultraviolet absorbers are usually non-reactive compounds, when used in paints, coatings, etc., they bleed out from the coating film, sublimation by drying and heating, solvents and There is a case where the chemicals are outflowable, the used amount of the ultraviolet absorbent is not retained, and the performance of the ultraviolet absorbent is hardly maintained.

  Therefore, a method has been known in which these ultraviolet absorbers are provided with a reactive group to react with resins used in paints, coating agents, ink binders, plastics, and the like (for example, see Patent Document 1). However, the reactive ultraviolet absorber containing these acryloyl groups and methacryloyl groups is a solid (powder), and is difficult to dissolve in other copolymerized monomers when copolymerized with other monomers. Handling was not easy. Further, the solubility in other copolymerizable monomers is limited, and the copolymer may not be uniformly distributed in the polymer when copolymerized.

  JP 2003-40937 A

  Therefore, the problem to be solved by the present invention is a reactive ultraviolet absorber which has good reactivity with other acrylic monomers, is easy to handle, and can impart weather resistance without bleed-out or outflow to a polymer. And a method for producing the same, a coating composition, and a polymer.

  Then, the present inventors studied a reactive ultraviolet absorber, and found a method of introducing a specific reactive group into an existing non-reactive ultraviolet absorber, and reached the present invention.

  <1> A reactive ultraviolet absorber represented by the following general formula (1).

(Wherein, R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group) .)
<2> A reactive ultraviolet absorber represented by the following general formula (2).

(R1 and R2 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.)
<3> A reactive ultraviolet absorber represented by the following general formula (3).

(R1 represents a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.)
<4> A method for producing a reactive ultraviolet absorber, comprising reacting a compound represented by the following general formula (4) with an isocyanate compound represented by the following general formula (5).

(R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)

(R represents a hydrogen atom or a methyl group.)
<5> A method for producing a reactive ultraviolet absorber in which a compound represented by the following general formula (6) is reacted with an isocyanate compound represented by the following general formula (5).

(R1 and R2 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)

(R represents a hydrogen atom or a methyl group.)
<6> A method for producing a reactive ultraviolet absorber in which a compound represented by the following general formula (7) is reacted with an isocyanate compound represented by the following general formula (5).

(R1 represents a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom.)

(R represents a hydrogen atom or a methyl group.)
<7> A coating composition comprising the reactive ultraviolet absorber according to any one of <1> to <3>.

  <8> A polymer produced by using the reactive ultraviolet absorber according to any one of <1> to <3> as a reactant.

  The present invention provides a reactive ultraviolet absorber which has good reactivity with other acrylic monomers, is easy to handle, and can provide a polymer with weather resistance without bleed-out or outflow, a production method thereof, and a coating composition. And a polymer.

4 is a graph showing an example of a measurement result of Example 1. 6 is a graph showing another example of the measurement results of Example 1.

  Hereinafter, the present invention will be described focusing on a reactive ultraviolet absorber. However, the present invention is not limited to the following embodiments.

  The reactive ultraviolet absorber of the present embodiment has one of the structures represented by the following general formulas (1), (2) and (3).

(R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.)
R1 to R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom. The alkyl group which may contain an oxygen atom is preferably an alkyl group having 1 to 8 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a secondary butyl group, Examples include an alkyl group such as a tertiary butyl group, a pentyl group, a neopentyl group, a hexyl group, an octyl group, and a 2-ethylhexyl group, and an alkyloxy group such as a propenyl group and an isopropenyl group.

  A may be any group as long as it contains an acryloyl group or a methacryloyl group.

  As a method for producing the compound represented by the general formula (1), a method of reacting a compound represented by the following general formula (4) with an isocyanate compound represented by the following general formula (5) is exemplified.

(R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)

(R represents a hydrogen atom or a methyl group.)
Specific compounds represented by the general formula (5) include isocyanate compounds containing an acryloyl group or a methacryloyl group, such as 2-Isocyanatoethyl acrylate and 2-Isocyanatoethyl methacrylate.

  The method of reacting the hydroxyl group of the compound represented by the general formula (4) with the isocyanate group of the compound represented by the general formula (5) utilizes a urethane polymerization reaction.

  In the urethane polymerization reaction, a catalyst can be used if necessary. The catalyst that can be used is not particularly limited as long as it is used for the urethane reaction, and examples thereof include an organotin catalyst, an organometallic catalyst (non-tin), and an amine catalyst.

  As a method for producing the compounds represented by the general formulas (2) and (3), an isocyanate compound represented by the general formula (5) is added to a compound represented by the following general formulas (6) and (7). A method for causing the reaction is mentioned.

(R1 and R2 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)

(R1 represents a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom.)
As a specific method for producing the compounds represented by the general formulas (2) and (3), the compound represented by the general formulas (6) and (7) is similar to the production method of the general formula (1). This is a method of reacting a hydroxyl group with an isocyanate group of the compound represented by the general formula (5) (urethane polymerization reaction). In the urethane polymerization reaction, a catalyst can be used if necessary.

  In the production of the ultraviolet absorber (the compound represented by the general formula (1), (2) or (3)) of the present embodiment, it has a hydroxyl group of the general formula (4), (6) or (7) And a solvent that dissolves a benzophenone-based ultraviolet absorber and a benzotriazole-based ultraviolet absorber. The solvent is not particularly limited as long as it does not react with the isocyanate group, and examples thereof include ketone solvents such as acetone and methyl ethyl ketone, aromatic solvents such as toluene, hydrocarbon solvents, and dimethylformamide.

  The reactive ultraviolet absorber (the compound represented by the general formula (1)) of the present embodiment has a benzophenone skeleton, and this benzophenone skeleton has an ultraviolet absorbing function (general formulas (2) and (3) Has a benzotriazole skeleton, and these benzophenone skeletons have an ultraviolet absorbing function.

  The reactive ultraviolet absorber of the present embodiment can impart a weathering function to the resin, but depending on the structure, other functions, such as improvement of water resistance, improvement of adhesion, and film forming property Functions such as improvement and improvement of blocking resistance can also be provided. The resin to be modified is not particularly limited and can be used for any resin, for example, by copolymerizing with a polymer resin such as an acrylic resin, a styrene resin, a vinyl acetate resin, a vinyl chloride resin, and a vinylidene chloride resin. Can be used.

  Examples of use of the reactive ultraviolet absorber of the present embodiment in an acrylate-based resin (a polymer produced using the reactive ultraviolet absorber as a reactant) include, for example, acrylic acid, methacrylic acid, and acrylic acid ester. And methacrylic acid esters, copolymers with acrylic monomers / styrene, acrylic monomers / vinyl acetate, acrylic monomers / acrylonitrile, acrylic monomers / butadiene, acrylic monomers / vinyl chloride, acrylic monomers / vinylidene chloride, and the like. Can be

  Examples of the use of the reactive ultraviolet absorber of the present embodiment in a styrene-based resin include copolymerization with a styrene monomer alone, and styrene and other vinyl monomers such as styrene / acrylonitrile, styrene / butadiene, and styrene / maleic acid. And copolymers.

Examples of use of the reactive ultraviolet absorber of the present embodiment in a vinyl acetate resin include copolymerization with a vinyl acetate monomer alone, vinyl acetate / styrene, vinyl acetate / vinyl chloride, vinyl acetate / acrylonitrile, vinyl acetate / maleic. Copolymers of vinyl acetate and other vinyl monomers such as acid, vinyl acetate / ethylene, vinyl acetate / vinylidene chloride, and the like can be mentioned.

  The polymerization method is not particularly limited, and a known polymerization reaction method such as an emulsion polymerization method, a solution polymerization method, and a suspension polymerization method can be used.

  The reactive ultraviolet absorber of the present embodiment can be used by being added to an ultraviolet-curable resin, and the ultraviolet-curable resin is not particularly limited, and may be an urethane-based, polyester-based, epoxy-based acrylate or methacrylate-based ultraviolet ray. It can be used in a curable coating composition to polymerize with other monomers and oligomers to exhibit an ultraviolet absorbing function.

  As a method for curing these coating compositions, a known curing method such as UV curing or EB curing can be used.

  The amount of the reactive ultraviolet absorber used in the present embodiment can be arbitrarily changed variously depending on the type of the monomer, the purpose of the modification, the required performance, and the like. 100% by mass can be used, and preferably 0.3 to 60% by mass is used.

  The polymer and the coating composition of the present embodiment are polymers obtained by copolymerizing the reactive ultraviolet absorber of the present invention with other polymerizable monomers and oligomers. The obtained polymer can be used for paints, adhesives, adhesives, ink binders, films, paper coating agents, sizing agents, fiber treatment agents, coating agents, various plastic products, and the like.

Hereinafter, the present invention will be described specifically with reference to Examples.
(Production Example 1)
In a 1 L four-neck separable flask equipped with a stirrer, a thermometer, a nitrogen inlet tube, and a reflux condenser, 214.22 g (1 mol) of 2,4-dihydroxybenzophenone and 280 g of methyl ethyl ketone as a solvent were charged. Is replaced with nitrogen and 2,4-dihydroxybenzophenone is dissolved. Next, 141.12 g (1 mol) of 2-isocyanate ethyl acrylate and 0.04 g of hydroquinone monomethyl ether as a polymerization inhibitor were added and reacted at 80 ° C. for 5 hours. After the reaction, the reaction was terminated when it was confirmed by FT-IR that there was no absorption of NCO groups (2250 nm). Next, the reaction product was transferred to a rotary evaporator, and methyl ethyl ketone as a solvent was removed at 40 ° C. and 0.2 bar to obtain the following compound A.

(Production Example 2)
The same apparatus as in Production Example 1 is charged with 214.22 g (1 mol) of 2,4-dihydroxybenzophenone and 280 g of methyl ethyl ketone as a solvent, and after displacing the atmosphere in the flask with nitrogen, 2,4-dihydroxybenzophenone is dissolved. Next, 155.15 g (1 mol) of 2-isocyanate ethyl methacrylate and 0.04 g of hydroquinone monomethyl ether as a polymerization inhibitor were added, and reacted at 80 ° C. for 5 hours. After the reaction, the reaction was terminated when it was confirmed by FT-IR that there was no absorption of NCO groups (2250 nm). Next, the reaction product was transferred to a rotary evaporator, and the solvent methyl ethyl ketone was removed at 40 ° C. and 0.2 bar to obtain the following compound B.

(Production Example 3)
The reaction and concentration were carried out in the same manner as in Production Example 1 except that 2,4-dihydroxybenzophenone in Production Example 1 was changed to 198.22 g (1 mol) of 4-hydroxybenzophenone, and the following compound C was obtained.

(Production Example 4)
The reaction and concentration were carried out in the same manner as in Production Example 2, except that 2,4-dihydroxybenzophenone in Production Example 2 was changed to 198.22 g (1 mol) of 4-hydroxybenzophenone, to obtain the following compound D.

(Production Example 5)
Reaction and concentration were carried out in the same manner as in Production Example 1 except that 2,4-dihydroxybenzophenone in Production Example 1 was changed to 228.24 g (1 mol) of 2-4-dihydroxy-4′-methylbenzophenone, and the following compound E was obtained. Obtained.

(Production Example 6)
The reaction and concentration were carried out in the same manner as in Production Example 2 except that 2,4-dihydroxybenzophenone in Production Example 2 was changed to 228.24 g (1 mol) of 2-4-dihydroxy-4′-methylbenzophenone, and the following compound F was obtained. Obtained.

(Production Example 7)
The reaction and concentration were carried out in the same manner as in Production Example 1 except that 2,4-dihydroxybenzophenone of Production Example 1 was changed to 227.2 g (1 mol) of 2- (2-4-dihydroxyphenyl) 2H-benzotriazole, and the following reaction was carried out. Compound G was obtained.

(Production Example 8)
The reaction and concentration were carried out in the same manner as in Production Example 2 except that 2,4-dihydroxybenzophenone of Production Example 2 was changed to 227.2 g (1 mol) of 2- (2-4-dihydroxyphenyl) 2H-benzotriazole, and the following reaction was carried out. Compound H was obtained.

(Production Example 9)
Same as Production Example 1, except that 2,4-dihydroxybenzophenone in Production Example 1 was changed to 255.27 g (1 mol) of 2- (2′-hydroxy-5 ′-(2-hydroxyethyl) phenyl) benzotriazole The reaction and concentration were performed to obtain the following compound I.

(Production Example 10)
Same as Production Example 2 except that 2,4-dihydroxybenzophenone of Production Example 2 was changed to 255.27 g (1 mol) of 2- (2′-hydroxy-5 ′-(2-hydroxyethyl) phenyl) benzotriazole The reaction and concentration were performed to obtain the following compound J.

[Evaluation]
In order to observe the ultraviolet absorption performance of the reactive ultraviolet absorbers (compounds A to J), emulsion polymerization was carried out with an acrylic ester according to the following method, and the resulting acrylic ester copolymer was obtained using an ultraviolet absorbance meter. The ultraviolet absorbance was measured and evaluated.
<Emulsion polymerization method>
Examples 1 to 10: Preparation of acrylate copolymer emulsion containing ultraviolet absorber <Preparation of pre-emulsion>
14.8 g of Latemul PD-430 (manufactured by Kao Corporation), 120.0 g of a reactive ultraviolet absorber (compounds A to J), 188.0 g of butyl acrylate, 40.0 g of ethyl acrylate,
A pre-emulsion was prepared by emulsifying 611.4 g of an unsaturated monomer mixture consisting of 14.4 g of acrylic acid, 19.2 g of 2-hydroxymethacrylate, and 215.0 g of water with a homomixer for 30 minutes.
(Emulsion polymerization)
340.0 g of water, 2.0 g of Aqualon AR-10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) were placed in a glass reaction vessel equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet tube and a dropping funnel. 50.0 g of the emulsion was charged and emulsified at 70 ° C. for 30 minutes. Next, as a polymerization initiator, a 50% aqueous solution of V-50 (manufactured by Wako Pure Chemical Industries, Ltd.) (2-2′-azobis (2-methylpropionamidine) hydrochloride) was dissolved to obtain a 5% aqueous solution. Was dropped into the above-mentioned reaction vessel, and immediately thereafter, the remaining pre-emulsion was continuously dropped into the reaction vessel over 90 minutes, and polymerization was carried out at 70 ° C. After the completion of the dropping of the pre-emulsion, the mixture was subjected to an aging reaction at 70 ° C. for 90 minutes, cooled to 30 ° C., adjusted to pH 4.0 to 5.0 with ammonia water, and treated with the ultraviolet absorbent-containing acrylic acid of Example 1. An ester copolymer emulsion (solid content: 40%) was obtained.

  Hereinafter, similarly, the reactive ultraviolet absorber compound was changed as shown in Table 1 below to obtain an acrylic ester copolymer emulsion containing the ultraviolet absorber of each example. The amount of the reactive ultraviolet absorber compound used was all 120 g.

  The physical properties (solid content, pH, particle size) of the ultraviolet absorbent-containing acrylate copolymer emulsion of each example were as shown in Table 1.

(Comparative Example 1)
300 g of 2,4-dihydroxybenzophenone, 700 g of water, and 20 g of Hytenol NF-17 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) (ammonium polyoxyethylene styrenated phenyl ether sulfate) were dispersed and stirred in a bead mill (manufactured by Co., Ltd.) for 3 hours. Thus, an ultraviolet absorbent dispersion having a particle diameter of 0.5 μm was obtained.
(Comparative Example 2)
50 g of the ultraviolet absorbent dispersion obtained in Comparative Example 1 and 50 g of HD RESIN 2PGN (manufactured by HYUN DAE HI-CHEM) were mixed to obtain an ultraviolet absorbent dispersion.
(Comparative Example 3)
Compound A of Example 1 was treated with UV-416 (manufactured by Pharmacia) (2-hydroxy-4).
-(2-acryloyloxy) ethoxybenzophenone) and the same emulsion polymerization as in Example 1 was carried out to obtain an ultraviolet absorbent-containing acrylate copolymer emulsion.

UV-416 is a powder, which was mixed with other acrylate monomers and then heated and dissolved to produce a pre-emulsion. However, since a small amount of crystals was generated with the passage of time, 100% of the reaction was carried out. There is no possibility.
(Comparative Example 4)
Emulsion polymerization was carried out in the same manner as in Example 1 except that Compound A of Example 1 was changed to CHISORB 593 (manufactured by DBC) (2- [2′hydroxy-5 ′-(methacryloyloxy) phenyl] benzotriazole), and ultraviolet light was irradiated. An acrylic ester copolymer emulsion containing an absorbent was obtained.

  CHISORB 593 also has a possibility that 100% of the pre-emulsion did not react because a small amount of crystals was generated with the lapse of time in the same manner as in Comparative Example 3.

  Table 2 shows the physical properties of the emulsion and the state of the emulsion in Comparative Examples 1 to 4.

(Test Example 1)
The ultraviolet absorbent-containing acrylate copolymer emulsions obtained in Examples 1 to 10 and Comparative Examples 3 and 4 and the ultraviolet absorbent dispersions obtained in Comparative Examples 1 and 2 are each 25 μm thick on a glass plate. And dried at 150 ° C., and then cooled to obtain a test piece. The state of these dried films and the state of the films were observed by immersing these test pieces in water at 25 ° C. for 1 hour. The results of the observation are shown in Table 3.

(Test Example 2)
UV absorber-containing acrylic ester copolymer emulsions obtained in Examples 1 to 10, UV absorber dispersions obtained in Comparative Examples 1 and 2, UV absorber-containing acrylic acid obtained in Comparative Examples 3 and 4 Specimens in which the concentration of each of the ester copolymer emulsions was adjusted to 50 ppm were prepared, and each sample was distilled water using a UV spectrophotometer (Thermo, Genesys 10S, USA) in a 10 mm square quartz glass cell. The transmittance (T%) at wavelengths of 300 nm and 250 nm of the test specimen was measured.

Table 4 shows the measurement results. FIG. 1 shows an example of the measurement results.
(Test Example 3)
UV absorber-containing acrylic ester copolymer emulsions obtained in Examples 1 to 10, UV absorber dispersions obtained in Comparative Examples 1 and 2, UV absorber-containing acrylic acid obtained in Comparative Examples 3 and 4 The ester copolymer emulsion was applied on a 0.5 mm glass plate so as to have a thickness of 20 μm to prepare a test piece. Using a UV spectrophotometer (manufactured by Thermo, Genesys 10S, USA), the transmittance (T%) of each test piece at a wavelength of 300 nm and 250 nm was measured for a 0.5 mm glass piece. did. Table 4 shows the measurement results. FIG. 2 shows an example of the measurement result.

  The reactive ultraviolet absorber compound of the present invention can be used to obtain a polymer resin having ultraviolet absorption performance by copolymerizing with a copolymerizable monomer and a crosslinkable monomer. The use of the agent makes it possible to obtain a film having excellent water resistance, durability, transparency, and weather resistance when applied to textiles, plastic products, and glass products.

  While most of the conventional reactive ultraviolet absorbers are powders, the properties of the reactive ultraviolet absorber compounds of the present invention are liquids, and when used after copolymerization, they may be mixed with other copolymerized monomers. It is possible to easily design a high-concentration ultraviolet absorbent-containing copolymer with good miscibility, and to develop a wide range of applications.

Claims (8)

A reactive ultraviolet absorber represented by the following general formula (1).
(R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.) A reactive ultraviolet absorber represented by the following general formula (2).
(R1 and R2 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.) A reactive ultraviolet absorber represented by the following general formula (3).
(R1 represents a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom; A represents a group containing an acryloyl group or a methacryloyl group.) A method for producing a reactive ultraviolet absorber, comprising reacting a compound represented by the following general formula (4) with an isocyanate compound represented by the following general formula (5).
(R1, R2, and R3 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)
(R represents a hydrogen atom or a methyl group.) A method for producing a reactive ultraviolet absorber, which comprises reacting a compound represented by the following general formula (6) with an isocyanate compound represented by the following general formula (5).
(R1 and R2 each independently represent a hydrogen atom, a hydroxyl group, or an alkyl group that may contain an oxygen atom.)
(R represents a hydrogen atom or a methyl group.) A method for producing a reactive ultraviolet absorber, comprising reacting a compound represented by the following general formula (7) with an isocyanate compound represented by the following general formula (5).
(R1 represents a hydrogen atom, a hydroxyl group, or an alkyl group which may contain an oxygen atom.)
(R represents a hydrogen atom or a methyl group.)   A coating composition comprising the reactive ultraviolet absorber according to claim 1.   A polymer produced by using the reactive ultraviolet absorbent according to claim 1 as a reactant.