Radiation Curable Composition and Curing Product Thereof, and Laminate Including the Same

• US 20080102262A1
• Filed: 11/08/2005
• Published: 05/01/2008
• Est. Priority Date: 11/08/2004
• Status: Abandoned Application

• Current Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Original Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Inventors: Matsuda, Osamu, Esaki, Akira
• Application Number:
  US11/718,835
• Publication Number:
  US 20080102262A1
• Time in Patent Office: Days
• US Class Current: 428/220
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: C08G 18/0823 containing carboxylate salt groups or groups forming them
• CPC Class Codes: C08G 18/44 Polycarbonates
• CPC Class Codes: C08G 18/4854 Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
• CPC Class Codes: C08G 18/6659 with compounds of group C08G18/34
• CPC Class Codes: C08G 18/6692 with compounds of group C08G18/34
• CPC Class Codes: C08G 18/672 Esters of acrylic or alkyl acrylic acid having only one group containing active hydrogen
• CPC Class Codes: C09D 175/16 having terminal carbon-to-carbon unsaturated bonds
• CPC Class Codes: G11B 7/24056 Light transmission layers lying on the light entrance side and being thinner than the substrate, e.g. specially adapted for Blu-ray® discs
• CPC Class Codes: G11B 7/2433 Metals or elements of Groups 13, 14, 15 or 16 of the Periodic Table, e.g. B, Si, Ge, As, Sb, Bi, Se or Te
• CPC Class Codes: G11B 7/2531 comprising glass
• CPC Class Codes: G11B 7/2533 comprising resins
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• CPC Class Codes: G11B 7/2542 consisting essentially of organic resins
• CPC Class Codes: G11B 7/2545 containing inorganic fillers, e.g. particles or fibres
• CPC Class Codes: G11B 7/2585 based on aluminium

Abstract

A radiation-curable composition capable of giving a cured product which has excellent transparency, mechanical strength and an excellent balance between surface hardness and resistance to deformation by heat/humidity; the cured product; and a multilayer structure which has a layer of the cured product and is suitable for use as an optical recording medium, etc, are provided A radiation-curable composition which comprises a monomer having a radiation-curable group and gives a cured product having the following properties: (1) when the cured product has a thickness of 100±5 μm, the cured product has a light transmittance at a wavelength of 550 nm of 80% or higher; (2) a multilayer structure where a layer of the cured product having a thickness of 100±5 μm is formed on a poly(ethylene terephthalate) film having a thickness of 100±5 μm, has a surface hardness of HB or higher; and (3) when a multilayer structure where the cured product having a thickness of 100±5 μm is formed on a disk made of a polycarbonate having a diameter of 130 mm and a thickness of 1.2±0.2 mm, is placed in an environment of 80° C. and 85% RH for 100 hours, then an absolute value |a| of an amount of warpage, a (mm), on the circumference of the multilayer structure is 0.5 mm or less.

Claims

1. A radiation-curable composition which comprises a monomer having a radiation-curable group and/or an oligomer thereof, wherein a cured product obtained by irradiating with ultraviolet in a light intensity of 1 J/cm², has the following properties (1) to (3):

(1) when the cured product has a thickness of 100±

5 μ

m, the cured product has a light transmittance at a wavelength of 550 nm of 80% or higher;

(2) a multilayer structure where a layer of the cured product having a thickness of 100±

5 μ

m is formed on a poly(ethylene terephthalate) film having a thickness of 100±

5 μ

m, has a surface hardness of HB or higher; and

(3) when a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a disk made of a polycarbonate having a diameter of 130 mm and a thickness of 1.2±

0.2 mm, is placed in an environment of 80°

C. and 85% RH for 100 hours, then an absolute value |a| of an amount of warpage, a (mm), on the circumference of the multilayer structure is 0.5 mm or less.

3. The radiation-curable composition of claim 1 or 2, wherein the monomer having a radiation-curable group and/or the oligomer thereof is one having a urethane bond.

4. The radiation-curable composition of claim 3, wherein the monomer and/or the oligomer thereof each having a urethane bond is one obtained by reacting at least a compound having two or more isocyanate groups in the molecule, a high-molecular polyol, and a (meth)acrylate having a hydroxyl group, in which the high-molecular polyol is one which contains two or more kinds of skeletons selected from the group consisting of a polyether polyol skeleton, a polyester polyol skeleton, and a polycarbonate polyol skeleton.

5. The radiation-curable composition of claim 4, wherein the monomer and/or the oligomer thereof each having a urethane bond is one obtained by further reacting a low-molecular polyol in which all the hydroxyl groups are connected by a hydrocarbon group.

8. The radiation-curable composition of any one of claims 1 to 7, which further comprises a compound having an ethylenically unsaturated group.

12. The radiation-curable composition of any one of claims 1 to 11, which comprises silica particles.

13. The radiation-curable composition of claim 12, wherein the silica particles are ones which have undergone a surface treatment with a surface-treating agent, and the proportion of the surface-treating agent to the silica particles is 200% by weight or higher.

14. A cured product obtained by curing the radiation-curable composition of any one of claims 1 to 13 by irradiation with a radiation.

15. The cured product of claim 14, which is for use as an optical material.

16. A multilayer structure which has a layer of the cured product of claim 14 or 15.

17. The multilayer structure of claim 16, which further comprises a hard coat layer on the cured product layer, the hard coat layer having a surface hardness of HB or higher.

18. An optical recording medium which comprises the multilayer structure of claim 16 or 17.

2. A radiation-curable composition which comprises a monomer having a radiation-curable group and/or an oligomer thereof, wherein the radiation-curable composition has a viscosity at 25°

C. of 1,000-5,000 cP, and a cured product obtained by irradiating with ultraviolet in a light intensity of 1 J/cm², has the following properties (1) to (3);

(1) when the cured product has a thickness of 100±

5 μ

m, the cured product has a light transmittance at a wavelength of 550 nm, of 80% or higher;

(2) a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a poly(ethylene terephthalate) film having a thickness of 100±

5 μ

m, has a surface hardness of HB or higher; and

(3) when a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a disk made of a polycarbonate having a diameter of 130 mm and a thickness of 1.2±

0.2 mm, is placed in an environment of 80°

C. and 85% RH for 100 hours and subsequently placed in an environment of 23°

C. and 65% RH for 168 hours, then an absolute value |b| of the amount of warpage, b (mm), is 0.5 mm or less.

6. A radiation-curable composition which comprises a monomer having a urethane bond and/or an oligomer thereof each obtained by reacting at least a compound having two or more isocyanate groups in the molecule, a high-molecular polyol, a (meth)acrylate having a hydroxyl group, and a low-molecular polyol in which all the hydroxyl groups are connected by a hydrocarbon group, wherein a cured product obtained by irradiating with ultraviolet in a light intensity of 1 J/cm², has the following properties (1) to (3):

(1) when the cured product has a thickness of 100±

5 μ

m, the cured product has a light transmittance at a wavelength of 550 nm, of 80% or higher;

(2) a multilayer structure where a layer of the cured product having a thickness of 100±

5 μ

m is formed on a poly(ethylene terephthalate) film having a thickness of 100±

5 μ

m, has a surface hardness of 2 B or higher; and

(3) when a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a disk made of a polycarbonate having a diameter of 130 mm and a thickness of 1.2±

0.2 mm, is placed in an environment of 80°

C. and 85% RH for 100 hours, then an absolute value |a| of an amount of warpage, a (mm), on the circumference, is 0.5 mm or less.

7. A radiation-curable composition which comprises a monomer having a urethane bond and/or an oligomer thereof each obtained by reacting at least a compound having two or more isocyanate groups in the molecule, a high-molecular polyol, a (meth)acrylate having a hydroxyl group, and a low-molecular polyol in which all the hydroxyl groups are connected by a hydrocarbon group, wherein the radiation-curable composition has a viscosity at 25°

C. of 1,000-5,000 centipoise (cP), and a cured product obtained by irradiating with ultraviolet in a light intensity of 1 J/cm², has the following properties (1) to (3);

(1) when the cured product has a thickness of 100±

5 μ

m, the cured product has a light transmittance at a wavelength of 550 nm, of 80% or higher;

(2) a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a poly(ethylene terephthalate) film having a thickness of 100±

5 μ

m, has a surface hardness of 2 B or higher; and

(3) when a multilayer structure where the cured product having a thickness of 100±

5 μ

m is formed on a disk made of a polycarbonate having a diameter of 130 mm and a thickness of 1.2±

0.2 mm, is placed in an environment of 80°

C. and 85% RH for 100 hours and subsequently placed in an environment of 23°

C. and 65% RH for 168 hours, then an absolute value |b| of an amount of warpage, b (mm), is 0.5 mm or less.

9. A radiation-curable composition which comprises:

a monomer having a urethane bond and/or an oligomer thereof each obtained by reacting at least a compound having two or more isocyanate groups in the molecule, a high-molecular polyol and a (meth)acrylate having a hydroxyl group;

a compound having an ethylenically unsaturated group;

a (meth)acrylate having an alicyclic skeleton; and

a photopolymerization initiator having a hydroxyl group, wherein the high-molecular polyol contains a polyether polyol skeleton in an amount of 20-90% by weight and a polyester polyol skeleton in an amount of 10-80% by weight, in all polyol skeletons, and the radiation-curable composition contains a terminal vinyl group of from 2.0×

10<sup>−

3</sup> to 4.3×

10<sup>−

3</sup> mol/g and a nitrogen atom in an amount of from 1.3×

10<sup>−

3</sup> to 2.5×

10<sup>−

3</sup> mol/g.

10. The radiation-curable composition of claim 9, wherein the monomer having a urethane bond and/or the oligomer thereof is one obtained by further reacting a low-molecular polyol in which all the hydroxyl groups are connected by a hydrocarbon group.

11. The radiation-curable composition of claim 9 or 10, wherein the content of acid group is from 0.1×

10<sup>−

4</sup> to 13×

10<sup>−

4</sup> eq/g.