Photocurable resin composition and molded article produced therefrom

Abstract

A photocurable resin composition and a molded article made therefrom are disclosed. The photocurable resin composition includes: 10 to 30 parts by weight of a (meth)acrylated polyurethane polymer; 0.1 to 30 parts by weight of an alkoxylated first bisphenol compound, wherein the molar ratio of alkoxy to phenol is 1 to 5, and the alkoxylated first bisphenol compound is (meth)acrylated; 30 to 60 parts by weight of an alkoxylated second bisphenol compound, wherein the molar ratio of alkoxy to phenol is 15 to 45, and the alkoxylated second bisphenol compound is (meth)acrylated; 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 product made from the same. Background Art

[0002] A 3D printer is a device that processes and laminates liquid, powdered resin, metal powder, solid and other materials according to design data to manufacture products. It can easily produce objects of the desired shape, so it is used to manufacture prototypes or objects of complex shapes.

[0003] 3D printer technology can be divided into photocuring lamination, laser sintering lamination, resin extrusion lamination, inkjet lamination, Polyjet lamination and film lamination according to the material.

[0004] Photocuring lamination is a method of manufacturing a molded object by curing a photocurable resin using a laser beam or strong ultraviolet rays (UV, Ultraviolet ray). Examples of the above-mentioned photocuring lamination method include a stereolithography apparatus (SLA) method, a digital light processing (DLP) method, or a light induced planar solidification (LIPS) method.

[0005] The laser sintering lamination method is a method of manufacturing a three-dimensional object by sintering powder materials under high temperature and pressure using a laser beam. Examples of the laser sintering lamination method include selective laser sintering (SLS).

[0006] The resin extrusion lamination method is a method of manufacturing a three-dimensional object by extruding a linear material through an injection head, and examples of the resin extrusion lamination method include Fused Deposition Modeling (FDM).

[0007] Inkjet lamination is a method of manufacturing a three-dimensional object by spraying a liquid adhesive onto a material through a nozzle of a printer head, and examples of the inkjet lamination include color jet printing (CJP).

[0008] The Polyjet lamination method is a hybrid of the photocuring method and the inkjet method, and is a method of manufacturing a three-dimensional object by curing with ultraviolet light while ejecting a material through a printer head. Examples of the Polyjet lamination method include Multi Jet Printing (MJP) and Polyjet.

[0009] The thin-film lamination method is a way to manufacture three-dimensional objects by cutting thin-sheet materials with a precision tool and then bonding them by heating. Examples of the above thin-film lamination method include Laminated Object Manufacturing (LOM) and Paper Lamination Technology (PLT).

[0010] Among the various 3D printing technologies described above, the photocuring lamination method has excellent surface roughness characteristics, so it is suitable for manufacturing dental materials with complex-shaped pores such as dental implants. These dental materials must ensure stability under humid conditions due to their inherent properties for use in human teeth and the like. However, the photoinitiators used in photocuring materials have problems of decomposition or elution when exposed to a humid environment, resulting in discoloration. In particular, since the commonly used phosphine oxide-based photoinitiators have unique colors, it is necessary to develop a technology to improve this color stability. Summary of the Invention

[0011] Technical Problem

[0012] An object of the present invention is to provide a photocurable resin composition having excellent color stability by reducing color change caused by moisture and a molded article manufactured therefrom.

[0013] Technical Means

[0014] According to one aspect, there is provided a photocurable resin composition, the photocurable resin composition comprising: 10 parts by weight to 30 parts by weight of a (meth)acrylated urethane polymer; 0.1 part by weight to 30 parts by weight of an alkoxylated first bisphenol compound, wherein the molar ratio of alkoxy / phenol is 1 to 5, and the alkoxylated first bisphenol compound is (meth)acrylated; 30 parts by weight to 60 parts by weight of an alkoxylated second bisphenol compound, wherein the alkoxy / phenol molar ratio is 15 to 45, and the alkoxylated second bisphenol compound is (meth)acrylated; and 0.1 part by weight to 5 parts by weight of a photoinitiator.

[0015] In one embodiment, the (meth)acrylation may be achieved by modifying at least one end to be 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.

[0016] In one embodiment, the urethane polymer may be polyurethane dimethacrylate.

[0017] In one embodiment, the above alkoxy group may be one selected from the group consisting of methoxy group, ethoxy group, propoxy group and butoxy group.

[0018] In one embodiment, the above photocurable resin composition may further include: 1 to 10 parts by weight of a (meth)acrylate compound containing at least one C3-C 20 cyclic alkyl group.

[0019] In one embodiment, the above (meth)acrylate compound may be isobornyl acrylate.

[0020] In one embodiment, the above photoinitiator may be one selected from the group consisting of acetophenone compounds, benzophenone compounds, triazine compounds, biimidazole compounds, thioxanthone compounds, oxime ester compounds and phosphorus oxide compounds.

[0021] In one embodiment, the above photoinitiator may be diphenyl-2,4,6-trimethylbenzoylphosphine oxide or phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0022] In one embodiment, the above photocurable resin composition may be a liquid composition for 3D printing using digital light processing method, stereolithography apparatus method or photoinduced planar solidification method.

[0023] In one embodiment, the above composition may be photocured by light having a wavelength of 360 nm to 405 nm.

[0024] According to another aspect, there is provided a molded article which is manufactured by irradiating light on the above photocurable resin composition.

[0025] Technical effects

[0026] According to one aspect, it is possible to provide a photocurable resin composition having excellent color stability by reducing color change caused by moisture and a molded article manufactured therefrom.

[0027] The effects of one aspect of this specification are not limited to the above effects, and it should be understood that all effects deduced from the structure of the invention described in the detailed description or claims of this specification are included. Detailed embodiments

[0028] Hereinafter, one aspect of this specification will be described with reference to various specific embodiments. However, the content described in this specification can be implemented in various different forms and is not limited to the embodiments described in this specification.

[0029] Throughout the specification, when describing that one component is "connected" to another component, it includes not only the case of "direct connection", but also the case of "connection with other components intervening therebetween". In addition, when a part is referred to as "comprising (or containing)" an element, unless otherwise expressly specified, it does not exclude any other elements, which may mean that a part may further comprise other elements.

[0030] In this specification, when describing a series of numerical ranges, unless otherwise specifically stated, these values have the precision of significant figures provided according to the standard rules in chemistry for significant figures. For example, 10 includes the range of 5.0 to 14.9, while the number 10.0 includes the range of 9.50 to 10.49.

[0031] In this specification, "(meth)acrylic-" means "methacryloyl-", "acryloyl-" or both.

[0032] Photocurable resin composition

[0033] The photocurable resin composition according to one aspect may include: 10 parts by weight to 30 parts by weight of a (meth)acrylated polyurethane polymer; 0.1 part by weight to 30 parts by weight of an alkoxylated first bisphenol compound, wherein the molar ratio of alkoxy / phenol is 1 to 5, and the above alkoxylated first bisphenol compound is (meth)acrylated; 30 parts by weight to 60 parts by weight of an alkoxylated second bisphenol compound, wherein the molar ratio of alkoxy / phenol is 15 to 45, and the above alkoxylated second bisphenol compound is (meth)acrylated; and 0.1 part by weight to 5 parts by weight of a photopolymerization initiator.

[0034] When the above photocurable resin composition can improve the problem of color change caused by the dissolution or decomposition of the photopolymerization initiator when exposed to moisture after curing, resulting in a decrease in color stability.

[0035] The above (meth)acrylation is achieved by modifying at least one end to be 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 the products of the above (meth)acrylation can be represented by the following chemical formula.

[0036] [Chemical formula]

[0037]

[0038] In the above chemical formula, R is a polymer or compound to be acrylated, and R' can be a single bond or methylene, ethylene, propylene or butylene. In the above chemical formula, the compound on the left represents an acrylated compound, and the compound on the right represents a methacrylated compound.

[0039] The content of the above polyurethane polymer can be 10 parts by weight to 30 parts by weight. For example, it can be 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 polyurethane polymer exceeds the above range, the mechanical properties of the molded article may deteriorate. The above (meth)acrylated polyurethane polymer can be urethane dimethacrylate, but is not limited thereto. The above composition can improve color stability by simultaneously containing a first bisphenol compound and a second bisphenol compound. The first bisphenol compound is a low alkoxylated bisphenol compound with a low alkoxy / phenol molar ratio, and the second bisphenol compound is a high alkoxylated bisphenol compound with a high alkoxy / phenol molar ratio. The content of the first bisphenol compound can be 0.1 part by weight to 30 parts by weight. For example, it can be 0.1 part by weight, 1 part 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 two of these values. The content of the second bisphenol compound can be 30 parts by weight to 60 parts by weight. For example, it can be 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 two of these values. If the contents of the first bisphenol compound and the second bisphenol compound exceed the above range, the color stability may deteriorate, or it may be unfavorable for 3D printing because it is not conducive to photocuring through the light source.

[0040] For example, the above alkoxy / phenol molar ratio can be represented by the EO / phenol value which is the molar ratio of ethylene oxide to phenol, but is not limited thereto.

[0041] The above alkoxy / phenol molar ratio is 1 to 5 and the (meth)acrylated alkoxylated first bisphenol compound can be ethoxylated bisphenol A dimethacrylate with 2 moles of ethylene oxide. For example, it can be a commercially available ethoxylated bisphenol A dimethacrylate (EO / phenol 2), but is not limited thereto.

[0042] The above alkoxy / phenol molar ratio is from 15 to 45, and the (meth)acrylated alkoxylated second bisphenol compound can be ethoxylated bisphenol A dimethacrylate with 30 moles of ethylene oxide. For example, it can be commercially available ethoxylated bisphenol A dimethacrylate (EO / phenol 30), but is not limited thereto.

[0043] The molar ratio of the above first bisphenol compound and the above second bisphenol compound can be 1:0.5 to 1.5 respectively. If the molar ratio of the bisphenol compound exceeds the above range, the color stability may deteriorate.

[0044] The above alkoxy can be one selected from the group consisting of methoxy, ethoxy, propoxy, and butoxy. The above bisphenol compound can be bisphenol A, bisphenol F, or bisphenol S, but is not limited thereto.

[0045] The above composition can further include (meth)acrylate compounds. The above (meth)acrylate compounds include at least one C3 - C 20 cycloalkyl group. As described above, when including a cycloalkyl group, the curing rate and curing ability for the photoinitiator can be excellent. In addition, it is possible to prevent the photoinitiator from decomposing or eluting when exposed to moisture.

[0046] The content of the above (meth)acrylate compounds can be from 1 part by weight to 10 parts by weight. For example, it can be 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 two of these values.

[0047] In one example, the above (meth)acrylate compound can be isobornyl acrylate, but is not limited thereto.

[0048] The above photoinitiator can be at least one selected from the group consisting of acetophenone compounds, benzophenone compounds, triazine compounds, biimidazole compounds, thioxanthone compounds, oxime ester compounds, and phosphine oxide compounds. For example, it can be diphenyl - 2,4,6 - trimethylbenzoylphosphine oxide or phenylbis(2,4,6 - trimethylbenzoyl)phosphine oxide, but is not limited thereto.

[0049] The above photoinitiator may elute or decompose in a humid environment, resulting in discoloration of the cured product. However, when the above composition includes a polyurethane polymer, a first bisphenol compound with a low alkoxy / phenol molar ratio, and a second bisphenol compound with a high alkoxy / phenol molar ratio at the same time, this discoloration can be prevented.

[0050] The above photocurable resin composition may be a liquid composition for 3D printing in a digital light processing (DLP) method, a stereolithography apparatus (SLA) method, or a light-induced planar solidification (LIPS) method. Therefore, a printer using a method of using a liquid resin can be used for the above 3D printing. A photocurable 3D printer is a printer that cures materials by irradiating light onto the area to be printed. Compared with other printing methods, the photocurable 3D printer has superior surface roughness and is beneficial for manufacturing complex structures.

[0051] In the above stereolithography apparatus method, an ultraviolet laser can be projected into a water tank filled with a photocurable resin composition to cure it, and then it can be laminated to manufacture a molded object. In the case of the above SLA 3D printing, the wavelength of the irradiated laser may vary according to the type of the composition, and the curing speed, the strength of the cured molded object, the surface roughness, etc. may also be different.

[0052] The above digital light processing method is a mask projection image curing method. By selectively projecting light onto the photocurable resin for curing, a molded object of a desired shape can be manufactured. Different from the method of usually producing products while lowering a modeling plate, products can be produced in the downward direction while the modeling plate moves upward. At this time, a molded object can be manufactured by projecting the light provided from a beam projector onto the 3D printing photocurable resin composition. That is, the modeling plate is cured sequentially in units of divided cross-sectional layers, so that a 3D molded object can be manufactured.

[0053] The above light-induced planar solidification method is a method of selectively projecting light onto the photocurable resin by using a planar light source such as an LCD or an LED to cure it. Therefore, different from the digital light processing method, it prevents the bending phenomenon of the light wavelength bent by a lens, and uniform photocuring can be performed regardless of the area.

[0054] The above photocurable composition can be photocured by light with a wavelength of 360 nm to 405 nm.

[0055] The above photocurable resin composition can be used for 3D printing and the manufacture of various dental materials. In particular, according to an embodiment, by using a photocurable resin composition satisfying a specific composition, excellent color stability can be achieved while satisfying the strength required for dental materials. If the composition of the above composition exceeds the above range, a sufficient crosslinked structure may not be formed only by photocuring, so the required physical properties may not be satisfied, or color change may occur under humid conditions, resulting in insufficient aesthetics.

[0056] Molded article

[0057] The molded article according to another aspect can be manufactured by irradiating the above-described photocurable resin composition with light.

[0058] The above light irradiation can be carried out by borrowing known SLA, DLP or LIPS methods.

[0059] The above molded article can be manufactured by 3D printing using a digital light processing method, a stereolithography apparatus method or a photoinduced planar solidification method. Therefore, compared with a molded article made by melting and shaping a filament, etc., the above molded article can have a smoother surface and a more complex structure.

[0060] The above molded article can be a dental material. When manufacturing the molded article by irradiating the above-described photocurable resin composition with light, the mechanical strength required for a dental material can be fully achieved, while improving the stability to moisture, thereby solving the problem of existing dental materials with insufficient aesthetics due to color change under actual use conditions.

[0061] Hereinafter, embodiments of the present specification will be described in more detail. However, the following experimental results are only representative experimental results in the above embodiments, and the embodiments etc. should not be construed as limiting or restricting the scope and content of the present specification. The effects of various embodiments of the present specification not explicitly presented below are specifically described in the corresponding parts.

[0062] Examples 1 to 7 and Comparative Examples 1 to 5

[0063] Mix polyurethane 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.

[0064] [Table 1]

[0065]

[0066] Comparative Example 9

[0067] Mix 10 parts by weight of polyurethane dimethacrylate, 50 parts by weight of ethoxylated bisphenol A dimethacrylate with 4 moles of ethylene oxide, 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.

[0068] Experimental Example 1

[0069] For the compositions of the above-mentioned examples and comparative examples, a disk sample with a diameter of 10 mm and a thickness of 2 mm was output using a 3D printing device equipped with a light source of 360 nm to 405 nm. After cleaning the above sample with an isopropyl alcohol cleaning solution, it was cured with a post-curing machine for 10 minutes to 30 minutes.

[0070] The above sample was exposed to various environments for 2 weeks, and the color stability was determined by analyzing the color difference (ΔE) of the above sample before and after exposure using a spectrophotometer.

[0071] - First condition: 25 °C

[0072] - Second condition: 40 °C and 80% relative humidity

[0073] - Third condition: Inside a PBS solution at 40 °C

[0074] [Table 2]

[0075] Classification First condition Second condition Third condition Example 1 ○ ○ ○ Example 2 ○ ○ ○ Example 3 ○ ○ ○ Example 4 ○ ○ ○ Example 5 ○ ○ ○ Example 6 ○ ○ ○ Example 7 ○ ○ △ Comparative Example 1 × × × Comparative Example 2 × × × Comparative Example 3 △ △ × Comparative Example 4 × × × Comparative Example 5 ○ △ △ Comparative Example 6 ○ △ △ Comparative Example 7 × × × Comparative Example 8 △ × × Comparative Example 9 ○ △ ×

[0076] (○: Good, △: Insufficient, ×: Poor)

[0077] Referring to Table 2 above, Examples 1 to 6 in which polyurethane, low-ethoxylated bisphenol A, and high-ethoxylated bisphenol A are combined showed excellent color stability under high humidity conditions or in a buffer solution similar to that in vivo, but Comparative Examples 1 to 9 had insufficient color stability in a humid environment.

[0078] In addition, the curing time of Examples 4 to 6 further containing isobornyl acrylate was reduced by less than half compared to Examples 1 to 3, and at the same time, the cured product had excellent mechanical strength and color stability.

[0079] The above description of this specification is merely illustrative. As long as it is an ordinary technician in the technical field to which this specification belongs, it can be understood that without changing the technical idea or essential features of this specification, it can also be easily deformed into other specific forms. Therefore, it should be understood that the above-mentioned examples are illustrative in all aspects, but not limited thereto. For example, each structural component described as a single type can also be implemented dispersedly, and similarly, the structural components described dispersedly can also be implemented in a combined form.

[0080] The scope of this specification is represented by the appended claims, rather than by the above detailed description, and all changes or deformation forms derived from the meaning, scope, and equivalent concepts of the claims should be interpreted as being included within the scope of this specification.

Claims

1. A photocurable resin composition, characterized in that, Comprising: 10 to 30 parts by weight of a (meth)acrylated polyurethane polymer; 0.1 to 30 parts by weight of a (meth)acrylated alkoxylated first bisphenol compound, wherein the molar ratio of alkoxy / phenol is 1 to 5; 30 to 60 parts by weight of a (meth)acrylated alkoxylated second bisphenol compound, wherein the alkoxy / phenol molar ratio is 15; and 0.1 to 5 parts by weight of a photoinitiator, The above alkoxy is an ethoxy group formed by ethylene oxide.

2. The photocurable resin composition according to claim 1, characterized in that, The above (meth)acrylation is formed by modifying at least one terminal with a group selected from the group consisting of acrylate and methacrylate.

3. The photocurable resin composition according to claim 2, characterized in that, The above acrylate includes one of methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate; The above methacrylate includes one of methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate.

4. The photocurable resin composition according to claim 1, characterized in that, The above (meth)acrylated polyurethane polymer is polyurethane dimethacrylate.

5. The photocurable resin composition according to claim 1, characterized in that, It further includes: 1 to 10 parts by weight of (meth)acrylate compounds containing at least one C3-C 20 cyclic alkyl group.

6. The photocurable resin composition according to claim 5, characterized in that, The above (meth)acrylate compound is isobornyl acrylate.

7. The photocurable resin composition according to claim 1, characterized in that, The above photoinitiator is one selected from the group consisting of acetophenone compounds, benzophenone compounds, triazine compounds, biimidazole compounds, thioxanthone compounds, oxime ester compounds, and phosphorus oxide compounds.

8. The photocurable resin composition according to claim 7, characterized in that, The above photoinitiator is diphenyl-2,4,6-trimethylbenzoylphosphine oxide or phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

9. The photocurable resin composition according to claim 1, characterized in that, The above photocurable resin composition is a liquid composition for 3D printing using digital light processing, stereolithography equipment, or photoinduced planar solidification methods.

10. The photocurable resin composition according to claim 1, characterized in that, The above composition is photocured by light with a wavelength of 360 nm to 405 nm.

11. A molded article, characterized in that, Manufactured by irradiating the photocurable resin composition according to any one of claims 1 to 10 with light.

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