Photocurable resin composition and molded article produced therefrom

Abstract

Disclosed is a photocurable resin composition and a molded article produced therefrom, which comprises: 10 to 30 parts by weight of a (meth)acrylated urethane polymer; 0.1 to 30 parts by weight of a (meth)acrylated alkoxylated first bisphenol compound having an alkoxy / phenol molar ratio of 1 to 5; 30 to 60 parts by weight of a (meth)acrylated alkoxylated second bisphenol compound having an alkoxy / phenol molar ratio of 15 to 45; and 0.1 to 5 parts by weight of a photopolymerization initiator.

Description

[Technical field]

[0001] The present invention relates to a photocurable resin composition and a molded article produced from the composition. [Background technology]

[0002] 3D printers are equipment that manufacture products by processing and layering materials such as liquids, powdered resins, metal powders, and solids based on design data. As they can easily produce objects of desired shapes, they are used to manufacture prototypes or objects with complex shapes.

[0003] Depending on the material, 3D printer technology can be divided into photocuring lamination, laser sintering lamination, resin extrusion lamination, inkjet lamination, polyjet lamination and thin film lamination.

[0004] The photocuring lamination method is a method of manufacturing molded products by curing photocuring resin with a laser beam or strong ultraviolet rays (UV). Examples of photocuring lamination methods include Stereo Lithography Apparatus (SLA), Digital Light Processing (DLP), and Light Induced Planar Solidification (LIPS).

[0005] The laser sintering lamination method is a method of manufacturing a three-dimensional object by sintering powdered materials at high pressure and high temperature using a laser beam. One such laser sintering lamination method is SLS (Selective Laser Sintering).

[0006] The resin extrusion lamination method is a method for manufacturing a three-dimensional object by extruding a wire-shaped material with an injection head, and one example of such a resin extrusion lamination method is FDM (Fused Deposition Modeling).

[0007] The inkjet lamination method is a method of manufacturing a three-dimensional object by spraying a liquid binder onto a material using a printer head nozzle. One such inkjet lamination method is CJP (Color Jetting Printing).

[0008] The Polyjet lamination method is a combination of the photocuring method and the inkjet method, in which material is sprayed from a printer head and cured with ultraviolet light at the same time to produce a three-dimensional object. There are two types of Polyjet lamination methods: MJP (Multi Jet Printing) and Polyjet.

[0009] The thin film lamination method is a method of manufacturing three-dimensional objects by cutting thin plate-shaped materials with a precision cutter and then heating them to bond them together. Examples of such thin film lamination methods include LOM (Laminated Object Manufacturing) and PLT (Paper Lamination Technology).

[0010] Among these various 3D printing technologies, the photocuring lamination method has excellent surface roughness characteristics and is suitable for manufacturing dental materials with complex void shapes such as imprints. Such dental materials must be stable under humid conditions due to their essential characteristics of being used in human teeth. However, photopolymerization initiators used in photocuring materials have the problem of being decomposed or eluted when exposed to a humid environment, causing discoloration. In particular, since commonly used phosphine oxide-based photopolymerization initiators have a unique hue, it is necessary to develop a technology that can improve this color stability. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention provides a photocurable resin composition having excellent color stability and reduced color change due to moisture, and a molded product produced from the composition. [Means for solving the problem]

[0012] According to one aspect, there is provided a photocurable resin composition comprising: 10 to 30 parts by weight of a (meth)acrylated urethane polymer; 0.1 to 30 parts by weight of a (meth)acrylated alkoxylated first bisphenol compound having an alkoxy / phenol molar ratio of 1 to 5; 30 to 60 parts by weight of a (meth)acrylated alkoxylated second bisphenol compound having an alkoxy / phenol molar ratio of 15 to 45; and 0.1 to 5 parts by weight of a photopolymerization initiator.

[0013] In one embodiment, the (meth)acrylate may be modified at least at one end with one selected from the group consisting of acrylate, methacrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, and butyl methacrylate.

[0014] In one embodiment, the urethane-based polymer may be urethane dimethacrylate.

[0015] In one embodiment, the alkoxy may be one selected from the group consisting of methoxy, ethoxy, propoxy, and butoxy.

[0016] In one embodiment, at least one of C3 to C 20 It may further contain 1 to 10 parts by weight of a (meth)acrylate compound containing a cyclic alkyl group.

[0017] In one embodiment, the (meth)acrylate compound may be isobornyl acrylate.

[0018] In an embodiment, the photopolymerization initiator may be at least one selected from the group consisting of an acetophenone-based compound, a benzophenone-based compound, a triazine-based compound, a non-imidazole-based compound, a thioxanthone-based compound, an oxime ester-based compound, and a phosphine oxide-based compound.

[0019] In one embodiment, the photoinitiator may be diphenyl-2,4,6-trimethylbenzoylphosphine oxide or phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide.

[0020] In one embodiment, the photocurable resin composition may be a liquid composition used in 3D printing using a digital light source processing method, a stereolithography device method, or a light-induced planar solidification method.

[0021] In one embodiment, the composition can be photocured at wavelengths between 360 and 405 nm.

[0022] According to another aspect, there is provided a molded product produced by irradiating the above-mentioned photocurable resin composition with light. Effect of the Invention

[0023] According to one aspect, it is possible to provide a photocurable resin composition having excellent color stability by reducing color change due to moisture, and a molded product produced therefrom.

[0024] The effects of one aspect of this specification are not limited to the effects described above, but should be understood to include all effects that can be inferred from the configurations described in the detailed description or claims of this specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] [Best Mode for Carrying Out the Invention] Although the present disclosure will be described in detail below with reference to specific examples, it should be understood that the present disclosure may be embodied in many different forms and is not limited to the examples set forth herein.

[0026] Throughout the specification, the term "connected" to another part includes not only "directly connected" but also "indirectly connected" with another member therebetween. In addition, the term "comprises" a certain component means that the part can further include the other component, not excluding the other component, unless otherwise specified.

[0027] When a range of numerical values ​​is recited herein, unless a specific range thereof is stated to the contrary, the values ​​have the precision of significant figures provided by standard rules in chemistry for significant figures, for example, the number 10 includes a range of 5.0 to 14.9, and the number 10.0 includes a range of 9.50 to 10.49.

[0028] As used herein, "(meth)acrylic" means "methacrylic," "acrylic," or both.

[0029] Photocurable resin composition According to one aspect, the photocurable resin composition may comprise: 10 to 30 parts by weight of a (meth)acrylated urethane polymer; 0.1 to 30 parts by weight of a (meth)acrylated alkoxylated first bisphenol compound having an alkoxy / phenol molar ratio of 1 to 5; 30 to 60 parts by weight of a (meth)acrylated alkoxylated second bisphenol compound having an alkoxy / phenol molar ratio of 15 to 45; and 0.1 to 5 parts by weight of a photopolymerization initiator.

[0030] The photocurable resin composition can improve the problem of a decrease in color stability due to a change in color caused by elution or decomposition of a photopolymerization initiator when exposed to moisture after curing.

[0031] The (meth)acrylate may be one in which at least one end is modified with one selected from the group consisting of acrylate, methacrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, and butyl methacrylate. Examples of such (meth)acrylates may be represented by the following chemical formula:

[0032] [ka]

[0033] In the formula, R is a polymer or compound to be (meth)acrylated, and R' may be a single bond or may be methylene, ethylene, propylene, or butylene. The compound on the left side of the formula is the acrylated one, and the compound on the right side is the methacrylated one.

[0034] The urethane polymer may be 10 to 30 parts by weight, for example, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, or a range between two of these values. If the content of the urethane polymer is out of the above range, the mechanical properties of the molded product may be deteriorated. The (meth)acrylated urethane polymer may be, but is not limited to, urethane dimethacrylate. The composition may improve color stability by simultaneously including a first bisphenol compound, which is a low alkoxylated bisphenol compound having a low alkoxy / phenol molar ratio, and a second bisphenol compound, which is a high alkoxylated bisphenol compound having a high alkoxy / phenol molar ratio. The content of the first bisphenol compound may be 0.1 to 30 parts by weight, for example, 0.1 parts by weight, 1 parts by weight, 5 parts by weight, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, or a range between any two of these values, and the content of the second bisphenol compound may be 30 to 60 parts by weight, for example, 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight, 55 parts by weight, 60 parts by weight, or a range between any two of these values. If the contents of the first and second bisphenol compounds are out of the above ranges, the color stability may be reduced or it may be disadvantageous to photocuring by a light source, which may be disadvantageous for 3D printing.

[0035] The molar ratio of alkoxy / phenol may be, for example, an EO / phenol value, which is a molar ratio of ethylene oxide to phenol, but is not limited thereto.

[0036] The alkoxylated first bisphenol compound having an alkoxy / phenol molar ratio of 1 to 5 and being (meth)acrylated may be ethoxylated bisphenol A dimethacrylate having an ethylene oxide molar number of 2, and for example, commercially available ethoxylated bisphenol A dimethacrylate (EO / phenol 2) can be used, but is not limited thereto.

[0037] The alkoxylated second bisphenol compound having an alkoxy / phenol molar ratio of 15 to 45 and being (meth)acrylated may be ethoxylated bisphenol A dimethacrylate having an ethylene oxide molar number of 30, for example, commercially available ethoxylated bisphenol A dimethacrylate (EO / phenol 30) can be used, but is not limited thereto.

[0038] The molar ratio of the first bisphenol compound to the second bisphenol compound may be 1:0.5 to 1.5, respectively. If the molar ratio of the bisphenol compounds is out of this range, the color stability may be reduced.

[0039] The alkoxy may be one selected from the group consisting of methoxy, ethoxy, propoxy and butoxy. The bisphenol-based compound may be, but is not limited to, bisphenol A, bisphenol F or bisphenol S.

[0040] The composition may further comprise a (meth)acrylate compound. The (meth)acrylate compound may comprise at least one C3 to C 20 The cyclic alkyl group may have an excellent curing speed and curing power with respect to the photopolymerization initiator, and may prevent the photopolymerization initiator from being decomposed or eluted when exposed to moisture.

[0041] The (meth)acrylate compound may be present in an amount of 1 to 10 parts by weight, for example, 1 part by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, or a range between any two of these values.

[0042] In one example, the (meth)acrylate compound may be isobornyl acrylate, but is not limited thereto.

[0043] The photopolymerization initiator may be at least one selected from the group consisting of acetophenone-based compounds, benzophenone-based compounds, triazine-based compounds, biimidazole-based compounds, thioxanthone-based compounds, oxime ester-based compounds, and phosphine oxide-based compounds, and may be, for example, diphenyl-2,4,6-trimethylbenzoylphosphine oxide or phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide, but is not limited thereto.

[0044] The photopolymerization initiator may dissolve or decompose in a moisture environment, resulting in a change in the color of the cured product. However, since the composition simultaneously contains a urethane polymer, a first bisphenol compound having a low alkoxy / phenol molar ratio, and a second bisphenol compound having a high alkoxy / phenol molar ratio, such a change in color can be prevented.

[0045] The photocurable resin composition may be a liquid composition used in 3D printing using a digital light processing (DLP) method, a stereo lithography apparatus (SLA) method, or a light induced planar solidification (LIPS) method. Thus, the 3D printing may be performed using a printer that uses a liquid resin. A photocurable 3D printer is a printer that irradiates light to an area where output is desired to cure a material, and has excellent surface roughness compared to other printing methods, and is advantageous for manufacturing structures with complex shapes.

[0046] The stereolithography method can produce molded objects by projecting an ultraviolet laser onto a water tank containing a photocurable resin composition, curing it, and stacking it. During SLA 3D printing, the wavelength of the irradiated laser can be changed depending on the type of composition, and the curing speed, strength, and surface roughness of the cured molded object can be changed.

[0047] The digital light source processing method is a mask projection image curing method, which selectively projects light onto a photocurable resin and hardens it to produce a molded product of a desired shape. Generally, the modeling plate moves up to produce a product in a downward direction, unlike a conventional method in which the modeling plate moves down. In this case, a molded product can be produced by projecting light provided by a beam projector onto a curable resin composition for 3D printing. That is, the modeling plate is cured in units of sliced ​​cross-sectional layers, and a 3D molded product can be produced.

[0048] The light-induced flat curing method selectively projects light onto the photocurable resin using a flat light source such as an LCD or LED to cure it. Unlike the digital light source processing method, it can prevent the phenomenon of light wavelength bending due to lens bending and perform uniform photocuring regardless of the size.

[0049] The photocurable resin composition can be photocured with light having a wavelength of 360 to 405 nm.

[0050] The photocurable resin composition can be used in 3D printing to manufacture various dental materials. In particular, according to one embodiment, the photocurable resin composition having a specific composition can be used to achieve the strength required for dental materials and excellent color stability. If the composition is outside the above range, the required physical properties may not be satisfied because a sufficient crosslinking structure is not formed by photocuring alone, or the color may change under moisture conditions, resulting in insufficient aesthetics.

[0051] molded product According to another aspect, a molded article can be produced by irradiating the above-mentioned photocurable resin composition with light.

[0052] The light irradiation can be carried out by using the known SLA, DLP, or LIPS method.

[0053] The molded product may be manufactured by 3D printing using a digital light source processing method, a stereolithography device method, or a light-induced planar solidification method. Therefore, the molded product may have a smoother surface and a more complex structure than molded products manufactured by a fusion modeling method in which a filament is melted and manufactured.

[0054] The molded product may be a dental material. When the molded product is produced by irradiating the photocurable resin composition with light, the mechanical strength required for the dental material can be sufficiently realized, and at the same time, the stability against moisture can be improved, thereby solving the problem of conventional dental materials that change in color under practical application conditions and lose aesthetics.

[0055] The examples of the present specification will be described in more detail below. However, the following experimental results are only representative experimental results among the above examples, and the scope and contents of the present specification should not be construed as being narrowed or limited by the examples. The respective effects of the various embodiments of the present specification that are not explicitly presented below will be specifically described in the relevant parts.

[0056] Examples 1 to 7 and Comparative Examples 1 to 5 Urethane dimethacrylate, ethoxylated bisphenol A dimethacrylate with 2 moles of ethylene oxide, ethoxylated bisphenol A dimethacrylate with 30 moles of ethylene oxide, isobornyl acrylate, and phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide were mixed.

[0057] [Table 1]

[0058] Comparative Example 9 10 parts by weight of urethane dimethacrylate, 50 parts by weight of ethoxylated bisphenol A dimethacrylate in which the mole number of ethylene oxide is 4, 10 parts by weight of triethylene glycol dimethacrylate, 10 parts by weight of tetrahydrofurfuryl methacrylate, 1 part by weight of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide, and 5 parts by weight of camphorquinone were mixed.

[0059] Experimental Example 1 The compositions of the examples and comparative examples were printed out into disk test pieces with a diameter of 10 mm and a thickness of 2 mm using a 3D printer equipped with a light source of 360 to 405 nm. The test pieces were washed with an isopropyl alcohol cleaning solution and then cured in a curing machine for 10 to 30 minutes.

[0060] The test pieces were exposed to various environments for two weeks, and the color difference (ΔE) of the test pieces before and after exposure was analyzed using a spectrophotometer to measure color stability.

[0061] -First condition: 25℃ -Second condition: 40℃, relative humidity 80% - Third condition: Inside PBS solution at 40℃

[0062] [Table 2]

[0063] Referring to Table 2, Examples 1 to 6, which combined urethane with low ethoxylated bisphenol A and high ethoxylated bisphenol A, showed excellent color stability under high humidity conditions and in a buffer solution similar to that in the body, but Comparative Examples 1 to 9 did not have high color stability in a moist environment.

[0064] Furthermore, in Examples 4 to 6, which further contained isobornyl acrylate, the curing time was reduced to less than half that of Examples 1 to 3, while the cured product exhibited excellent mechanical strength and color stability.

[0065] The above description of the present specification is merely illustrative, and a person having ordinary skill in the art to which one aspect of the present specification belongs can easily understand that the present specification can be easily modified into other specific forms without changing the technical ideas and essential features described in the present specification. Therefore, the above-described embodiments should be understood to be illustrative in all respects and not limiting. For example, each component described as a single type can be implemented in a distributed form, and similarly, each component described as a distributed type can be implemented in a combined form.

[0066] The scope of this specification is indicated by the claims set forth below, and all modifications and variations derived from the meaning and scope of the claims and their equivalent concepts must be interpreted as being included in the scope of the present invention.

Claims

1. 10 to 30 parts by weight of a (meth)acrylated urethane polymer; 0.1 to 30 parts by weight of a (meth)acrylated alkoxylated first bisphenol-based compound having an alkoxy / phenol molar ratio of 1 to 5; 30 to 60 parts by weight of a (meth)acrylated alkoxylated second bisphenolic compound having an alkoxy / phenol molar ratio of 15 to 45; and A photocurable resin composition comprising 0.1 to 5 parts by weight of a photopolymerization initiator.

2. 2. The photocurable resin composition according to claim 1, wherein at least one end of the (meth)acrylated urethane polymer is modified with one selected from the group consisting of acrylate, methacrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, and butyl methacrylate.

3. The photocurable resin composition according to claim 1 , wherein the urethane polymer is urethane dimethacrylate.

4. 2. The photocurable resin composition according to claim 1, wherein the alkoxy contained in the first bisphenol compound and the second bisphenol compound is one selected from the group consisting of methoxy, ethoxy, propoxy, and butoxy.

5. At least one C ３ ~C ２０ 2. The photocurable resin composition according to claim 1, further comprising 1 to 10 parts by weight of a (meth)acrylate compound containing a cyclic alkyl group.

6. The photocurable resin composition according to claim 5 , wherein the (meth)acrylate compound is isobornyl acrylate.

7. 2. The photocurable resin composition according to claim 1, wherein the photopolymerization initiator is at least one selected from the group consisting of an acetophenone-based compound, a benzophenone-based compound, a triazine-based compound, a biimidazole-based compound, a thioxanthone-based compound, an oxime ester-based compound, and a phosphine oxide-based compound.

8. The photocurable resin composition according to claim 7, wherein the photopolymerization initiator is diphenyl-2,4,6-trimethylbenzoylphosphine oxide or phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide.

9. The photocurable resin composition according to claim 1, which is a liquid composition used in 3D printing by digital light source processing, stereolithography device method, or light-induced planar solidification method.

10. The photocurable resin composition according to claim 1, wherein the composition is photocured at a wavelength of 360 to 405 nm.

11. A molded product produced by irradiating the photocurable resin composition according to any one of claims 1 to 10 with light.

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