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JP-7856573-B2 - Curable composition and its cured product

JP7856573B2JP 7856573 B2JP7856573 B2JP 7856573B2JP-7856573-B2

Inventors

  • 鎌田 武
  • 前津 成俊
  • 渡部 淳

Assignees

  • 株式会社ダイセル

Dates

Publication Date
20260511
Application Date
20211005
Priority Date
20201007

Claims (16)

  1. A curable composition comprising a polyol compound (A) having an isocyanurate skeleton, a compound (B) having a hydroxyl group and a (meth)acryloyl group, and a polyisocyanate compound (C) having an isocyanurate skeleton and isocyanate groups other than the isocyanurate skeleton.
  2. The curable composition according to claim 1, wherein the polyol compound (A) is compound (a) represented by the following formula (1). [In the formula, R1 to R3 are the same or different groups represented by the following formula (1a)] (In formula (1a), L1 and L2 are the same or different alkylene groups having 1 to 10 carbon atoms, and m is a number of 0 or more. However, m in R1 to R3 cannot be 0 at the same time. The bonds indicated by the wavy lines are bonded to the nitrogen atom in the formula.)
  3. The curable composition according to claim 1 or 2, wherein the compound (B) is a compound (b) represented by the following formula (2"). [In the formula, R4 is H or CH3 . R6 is the group represented by formula (2b) below.] (In formula (2b), L6 and L7 are the same or different alkylene groups having 1 to 10 carbon atoms, and n is a number of 0 or more. The wavy bond is attached to the oxygen atom in formula (2").)
  4. The curable composition according to any one of claims 1 to 3, wherein the polyisocyanate compound (C) is a compound (c) represented by the following formula (3). [In formula (3), L3 to L5 are the same or different alkylene groups having 1 to 10 carbon atoms.]
  5. The curable composition according to any one of claims 1 to 4, wherein the compound (B) is contained in an amount of 1 to 70 parts by weight per 100 parts by weight of the polyol compound (A).
  6. A curable composition according to any one of claims 1 to 5, comprising the polyol compound (A) and the compound (B) in a ratio such that the molar ratio (former/latter) of hydroxyl groups of the polyol compound (A) to hydroxyl groups of the compound (B) is 1.5 to 50.
  7. The curable composition according to any one of claims 1 to 6, wherein the equivalent ratio (NCO/OH) of the NCO group of the polyisocyanate compound (C) to the OH group in the polyol compound (A) and the compound (B) is in the range of 0.2 to 2.0.
  8. Furthermore, the curable composition according to any one of claims 1 to 7, wherein the photopolymerization initiator (D) is contained in an amount of 1 to 5 parts by weight per 100 parts by weight of the total of the polyol compound ( A ), the compound (B), and the polyisocyanate compound (C).
  9. Furthermore, the curable composition according to any one of claims 1 to 8, wherein the polysiloxane derivative (E) is contained in an amount of 0.1 to 0.5 parts by weight per 100 parts by weight of the total of the polyol compound (A), the compound (B), and the polyisocyanate compound (C).
  10. A curable composition according to any one of claims 1 to 9, which is a dual-curing type coating agent.
  11. An active energy ray curable film containing a (meth)acryloyl group-terminated urethane prepolymer comprising a polyol compound (A) having an isocyanurate skeleton, a compound (B) having a hydroxyl group and a (meth)acryloyl group, and a polyisocyanate compound (C) having an isocyanurate skeleton as constituent monomers.
  12. A cured product of the curable composition according to any one of claims 1 to 10.
  13. A cured product of the active energy ray curable film according to claim 11.
  14. A plastic molded article in which a coating made of the cured product according to claim 12 or 13 covers at least a portion of the surface of the substrate to be coated.
  15. A method for producing an active energy ray curable film, comprising: heat-treating a coating film made from a curable composition according to any one of claims 1 to 10; and producing an active energy ray curable film containing an active energy ray curable film containing a (meth)acryloyl group-terminated urethane prepolymer as constituent monomers, comprising a polyol compound (A) having an isocyanurate skeleton, a compound (B ) having a hydroxyl group and a (meth)acryloyl group, and a polyisocyanate compound (C) having an isocyanurate skeleton.
  16. A method for manufacturing a plastic molded product comprising the following steps. Step 1: The active energy ray-curable film described in claim 11 is placed in close contact with the recess of the mold, and then molten plastic is filled into it. Step 2: The plastic filled into the recess of the mold is solidified or cured. Step 3: The contents are removed from the mold, and the film is cured by irradiation with active energy rays.

Description

This disclosure relates to a curable composition for decorative films and a cured product thereof. This disclosure claims priority to Japanese Patent Application No. 2020-169881, filed in Japan on October 7, 2020, which is incorporated herein by reference. Polyurethane resins possess flexibility, elasticity, and strength. Therefore, compositions for polyurethane resin molding are used in coatings and other applications. For example, coatings used to cover plastic substrates that constitute vehicle components or electronic devices are required to form a film with good adhesion to the substrate, hardness, and scratch resistance. Examples of such coating agents include the compositions described in Patent Documents 1, 2, and 3. Japanese Patent Application Publication No. 04-130119Japanese Patent Publication No. 2011-137145Special Publication No. 2015-530295 [Curable composition] The curable composition of this disclosure comprises a polyol compound (A), an acrylic compound (B), and a polyisocyanate compound (C). The curable composition of this disclosure may also contain other components in addition to the above components. <Polyol compound (A)> Polyol compound (A) is a compound having multiple hydroxyl groups. The number of hydroxyl groups in polyol compound (A) is, for example, two or more, preferably two to four, and particularly preferably three to four. Polyol compound (A) also has an isocyanurate skeleton. Therefore, the resulting cured product has a high crosslinking density and exhibits excellent hardness, scratch resistance, and drug resistance. The polyol compound (A) is, for example, compound (a) represented by the following formula (1). [In the formula, R1 to R3 are the same or different groups represented by the following formula (1a)] (In formula (1a), L1 and L2 are the same or different alkylene groups having 1 to 10 carbon atoms, and m is a number of 0 or more. However, m in R1 to R3 cannot be 0 at the same time. The bonds indicated by the wavy lines are bonded to the nitrogen atom in the formula.) Examples of the alkylene group having 1 to 10 carbon atoms include linear or branched alkylene groups such as methylene group, methylmethylene group, dimethylmethylene group, ethylene group, propylene group, trimethylene group, butylene group, 1-methyltrimethylene group, 2-methyltrimethylene group, 1,1'-dimethylethylene group, pentylene group, hexylene group, heptylene group, octylene group, 2-ethylhexylene group, nonylene group, and desilene group. For L1 , an alkylene group having 1 to 3 carbon atoms is preferred. Furthermore, a linear alkylene group is preferred for L1 . As L2 , an alkylene group having 1 to 8 carbon atoms is preferred, and an alkylene group having 4 to 6 carbon atoms is particularly preferred. Furthermore, a linear alkylene group is preferred as L2 . In formula (1a), m is the average degree of polymerization of the units shown in parentheses in formula (1a), and is a number greater than or equal to 0. m is, for example, 0 to 7, and from the viewpoint of improving drug resistance by increasing the density of the network structure as the distance between crosslinking points of the resulting cured product decreases, it is preferably 0 to 4, more preferably 0 to 3, even more preferably greater than 0 and 3 or less, particularly preferably greater than 0 and 2 or less, and most preferably 1 to 2. The number-average molecular weight (Mn: on a standard polystyrene basis) of compound (a) is, for example, less than 800. From the viewpoint of improving drug resistance by reducing the distance between crosslinking points in the resulting cured product, which leads to a higher density of the network structure, it is preferably 570 to 630, more preferably 580 to 620, and particularly preferably 590 to 615. Furthermore, the molecular weight dispersion (weight-average molecular weight Mw/number-average molecular weight Mn) of compound (a) is preferably 1.0 to 1.5, more preferably 1.0 to 1.3, and even more preferably 1.0 to 1.2. The number-average molecular weight and molecular weight dispersion of compound (a) can be measured using the apparatus and conditions described in the examples later. The hydroxyl value (KOH mg/g) of compound (a) is, for example, 200 to 400, and more preferably 260 to 300, more preferably 270 to 290, and even more preferably 275 to 285, in that it can improve the hardness, scratch resistance, and drug resistance of the resulting cured product. The hydroxyl value can be measured by the hydroxyl value measurement method described in JIS-K1557. Compound (a) can be produced, for example, by ring-opening polymerization of a lactone starting from the hydroxyl group of formula (1') below. L1 in formula (1') is the same as L1 in formula (1a). The three L1s in formula (1') may be the same or different. Examples of the aforementioned lactones include α-acetolactone, β-propiolactone, γ-butyrolactone, δ-valerolactone, and ε-caprolactone. The curable composition of this disclosure