WO2023163241A1 - 3d printer photo curing composition and preparation method therefor - Google Patents

Abstract

The present invention relates to a 3D printer photo curing composition and a preparation method therefor, the 3D printer photo curing composition additionally comprising nanoclay, being uniformly distributed so as to reinforce the mechanical properties of a printout output by 3D printing, and enabling a 3D-printable viscosity to be maintained. In addition, the photo curing composition is used for 3D printing so as to be output and manufactured in a form suitable for the oral structure of a patient, has excellent mechanical properties such that orthodontic force can be increased, and, during heat provision, enables shape changing and restoration so as to provide a transparent orthodontic device capable of exhibiting an enhanced orthodontic effect.

Description

Photocurable composition for 3D printer and method for producing the same

The present invention relates to a photocurable composition for a 3D printer and a method for producing the same, and more particularly, to a photocurable composition capable of producing an output product using a DLP-type 3D printer and a method for producing the same.

3D printing is a process technology that outputs a three-dimensional shape by repeatedly stacking two-dimensional cross sections using digitally designed data. Design design or modification is very free, and the cost and time required for prototyping can be greatly reduced.

In addition, according to 3D printing technology, since even products with complex shapes can be easily produced, the types of products that can be produced using 3D printing technology can be said to be virtually endless. As a result, 3D printing technology is expected to lead industrial innovation by changing the paradigm of technology in many fields such as manufacturing, medical, and IT fields.

3D printer technology can be divided into photocuring lamination method, laser sintering lamination method, resin extrusion lamination method, inkjet lamination method, polyjet lamination method, and thin film lamination method according to the material.

The double photocuring lamination method is a method of manufacturing a molded product by curing a photo curing resin with a laser beam or strong ultraviolet (UV, Ultraviolet ray). , SLA) and digital light processing (DLP).

Recently, 3D printing technology is being used in various medical fields, and it is very efficient in terms of manufacturing time, cost, and process compared to conventional cutting. In particular, the photocurable lamination method has excellent surface roughness and can be used in the medical field where it is necessary to manufacture a molded product with a complex shape.

However, as mentioned above, in the case of using a material for a conventional 3D printer, there is a problem in that it is difficult to apply to the medical field due to limitations in physical properties for the output, and thus, a photocurable polymer 3D that can be applied to various medical fields It is urgent to develop materials for printers.

[Prior art literature]

[Patent Literature]

(Patent Document 1) KR 10-2020-0120992

An object of the present invention is to provide a photocurable composition for a 3D printer and a method for producing the same.

Another object of the present invention is to further include nano-clay in the photocurable composition for 3D printers to enhance the mechanical properties of the output printed by 3D printing and to maintain a viscosity capable of 3D printing. A photocurable composition for 3D printers is to provide

Another object of the present invention is to provide a manufacturing method capable of preparing a photocurable composition capable of 3D printing by uniformly distributing nano-clay in the photocurable composition.

Another object of the present invention is to apply 3D printing technology, can be output and manufactured in a form suitable for the patient's oral structure, can increase the corrective force due to excellent mechanical properties, and can change and restore the shape when heat is provided It can be provided as a transparent orthodontic appliance capable of exhibiting a high orthodontic effect.

In order to achieve the above object, a photocurable composition for a 3D printer according to an embodiment of the present invention includes a photocurable oligomer; reactive monomers; photoinitiators; and nano-clay, wherein the nano-clay may enhance mechanical properties of an output product output by 3D printing due to an interaction between a reactive monomer and electrical attraction.

The nano-clay is sepiolite, and the sepiolite is in the form of a single fiber, has an average length of 0.2 to 4 μm, a width of 10 to 30 nm, and an average thickness of 5 to 10 nm.

The photocurable oligomer is a compound represented by Formula 1 below:

[Formula 1]

[Formula 2]

[Formula 3]

here,

n is an integer from 1 to 1,000;

A is a compound represented by Formula 2 or Formula 3,

* means the part to be combined,

R ₁ to R ₆ are the same as or different from each other, and each independently represents hydrogen, heavy hydrogen, a cyano group, a nitro group, a halogen group, a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted cyclo group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 24 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, A substituted or unsubstituted heteroaryl group having 5 to 60 carbon atoms, a substituted or unsubstituted heteroarylalkyl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, A substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylamino group having 2 to 24 carbon atoms, or a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms , It is selected from the group consisting of a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms and a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms,

The substituted alkylene group, substituted arylene group, substituted heteroarylene group, substituted cycloalkylene group, substituted alkyl group, substituted cycloalkyl group, substituted alkenyl group, substituted alkynyl group, substituted aralkyl group, substituted aryl Group, substituted heteroaryl group, substituted heteroarylalkyl group, substituted alkoxy group, substituted alkylamino group, substituted arylamino group, substituted aralkylamino group, substituted heteroarylamino group, substituted alkylsilyl group, substituted aryl The silyl group and the substituted aryloxy group are hydrogen, deuterium, cyano group, nitro group, halogen group, hydroxy group, alkyl group having 1 to 30 carbon atoms, cycloalkyl group having 1 to 20 carbon atoms, alkenyl group having 2 to 30 carbon atoms, and 2 to 24 carbon atoms. alkynyl group, aralkyl group having 7 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, heteroaryl group having 5 to 60 nuclear atoms, heteroarylalkyl group having 6 to 30 carbon atoms, alkoxy group having 1 to 30 carbon atoms, and 1 carbon atom to 30 alkylamino groups, C6-30 arylamino groups, C6-30 aralkylamino groups, C2-24 heteroarylamino groups, C1-30 alkylsilyl groups, C6-30 arylsilyl groups, and It is substituted with one or more substituents selected from the group consisting of aryloxy groups having 6 to 30 carbon atoms, and when substituted with a plurality of substituents, they are the same as or different from each other.

The reactive monomer is an acrylate-based monomer.

A transparent orthodontic device according to another embodiment of the present invention includes the photocurable composition for the 3D printer.

A method for preparing a photocurable composition for a 3D printer according to another embodiment of the present invention includes: 1) mixing and stirring at least one reactive monomer; 2) preparing a first mixture by adding nanoclay to the reactive monomer, pulverizing and dispersing; 3) preparing a second mixture by adding a photocurable oligomer heated in an oven at 50 to 70° C. for 10 to 15 hours into the first mixture; and 4) adding a photoinitiator to the second mixture, mixing, and defoaming.

The present invention further comprises a nano-clay in the photocurable composition for a 3D printer, is uniformly distributed, enhances mechanical properties of the output printed by 3D printing, and maintains a viscosity capable of 3D printing. A photocurable type for a 3D printer. Compositions and methods for their preparation.

In addition, by 3D printing using the photocurable composition, it can be output and manufactured in a form suitable for the oral structure of the patient, and the mechanical properties are excellent to increase the corrective force, and when heat is provided, the change and restoration of the shape It is possible to provide a transparent orthodontic appliance capable of exhibiting a high orthodontic effect.

1 is an evaluation result for storage stability of a photocurable composition according to an embodiment of the present invention.

2 relates to the structure of sepiolite according to an embodiment of the present invention.

3 relates to the structure of sepiolite according to an embodiment of the present invention.

4 is a schematic view of the content of sepiolite and its alignment according to an embodiment of the present invention.

5 is a result of rheological shear characteristics of a photocurable composition according to an embodiment of the present invention.

6 is a result of the rheological yield characteristics of a photocurable composition according to an embodiment of the present invention.

7 is a result of measuring stress change over time of a photocurable composition according to an embodiment of the present invention.

8 is a result of the rheological properties of the photocurable composition according to an embodiment of the present invention by UV irradiation.

9 is a result of mechanical tensile properties of a 3D printed output according to an embodiment of the present invention.

10 is a strain-stress curve change result according to a change in the content of sepiolite according to an embodiment of the present invention.

The present invention relates to a photocurable composition for a 3D printer and a method for preparing the same, including a photocurable oligomer; reactive monomers; photoinitiators; and a nano-clay, wherein the nano-clay relates to a photocurable composition for a 3D printer capable of enhancing mechanical properties of an output product output by 3D printing due to an interaction between a reactive monomer and electrical attraction.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

3D printing of the present invention refers to a process of manufacturing a three-dimensional object by laminating materials using 3D digital data. In this specification, as 3D printing technologies, DLP (Disital Light Processing), SLA (Stereo Lithography Apparatus), and PolyJet method are mainly described, but it can be understood that they are applicable to other 3D printing technologies.

The photocurable composition of the present invention is a material that is cured by light irradiation, and refers to a polymer that is crosslinked and polymerized into a polymer network structure. In this specification, the description is centered on UV light, but it is not limited to UV light and can be applied to other lights as well.

A photocurable composition for a 3D printer according to an embodiment of the present invention includes a photocurable oligomer; reactive monomers; photoinitiators; and nano-clay, wherein the nano-clay may enhance mechanical properties of an output product output by 3D printing due to an interaction between a reactive monomer and electrical attraction.

The nano-clay is characterized in that it is sepiolite, but the nano-clay is not limited to sepiolite, and any nano-clay that can be included in a photocurable composition for a 3D printer to enhance mechanical properties is not limited thereto. Available.

Polymer composite technology can be applied to overcome the limitations of mechanical strength of 3D printing materials. However, there are several problems in applying the composite material to 3D printing. The most important issue is the size of additives used in composite materials. As the size of the additive increases, the size of the printing gap also increases, and as a result, a problem of lowering the printing resolution may occur.

In order to avoid the above problems, nano-sized materials may be used as additives. In the case of graphene, carbon nanotube (CNT), etc., which are conventionally known as nano-sized materials, price competitiveness may be a problem. On the other hand, nanoclay has a reasonable price, making it more suitable for industrial applications. Among nanoclays, sepiolite is a hydrated magnesium silicate with a half unit cell formula of Mg ₈ Si ₁₂ O ₃₀ (OH) ₄ .12H ₂ O.

The sepiolite has a cross-sectional chemical structure as shown in FIG. 2 and a lettis crystal form as shown in FIG. 3. More specifically, it is a needle-like or fiber-like shape composed of several blocks and tunnels parallel to the fiber direction. Each structural block contains a central octahedral magnesium (MgOH ₆ ) sheet sandwiched between two tetrahedral silica (SiO ₄ ) sheets. A single sepiolite fiber is 0.2 to 4 μm long, 10 to 30 nm wide, and 5 to 10 nm thick.

When sepiolite is included as nano-clay, a viscosity capable of 3D printing is maintained in the photocurable composition, and high mechanical strength can be exhibited for the printed object.

That is, when a large amount of nano-clay is included, the viscosity of the photocurable composition increases, and when the viscosity increases, the composition cannot be manufactured as an output product through a 3D printer. When the nano-clay is included in a certain amount or more, the mechanical strength of the output may increase. However, since a high-viscosity composition cannot be used for 3D printing, the viscosity of the photocurable composition is preferably included within a certain range.

Accordingly, the photocurable composition may include 0.5 to 5 parts by weight of nanoclay and 1 part by weight of a photoinitiator based on 100 parts by weight of the UV resin. The UV resin includes a photocurable oligomer and a reactive oligomer. When mixed and used within the above range, not only can it be manufactured as an output using a 3D printer, but also the manufactured output can exhibit excellent mechanical strength. More specifically, the 3D printer is a DLP type 3D printer.

The photocurable oligomer may be a compound represented by Formula 1 below:

[Formula 1]

[Formula 2]

[Formula 3]

here,

n is an integer from 1 to 1,000;

A is a compound represented by Formula 2 or Formula 3,

* means the part to be combined,

R ₁ to R ₆ are the same as or different from each other, and each independently represents hydrogen, heavy hydrogen, a cyano group, a nitro group, a halogen group, a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted cyclo group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 24 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, A substituted or unsubstituted heteroaryl group having 5 to 60 carbon atoms, a substituted or unsubstituted heteroarylalkyl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, A substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylamino group having 2 to 24 carbon atoms, or a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms , It is selected from the group consisting of a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms and a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms,

The substituted alkylene group, substituted arylene group, substituted heteroarylene group, substituted cycloalkylene group, substituted alkyl group, substituted cycloalkyl group, substituted alkenyl group, substituted alkynyl group, substituted aralkyl group, substituted aryl Group, substituted heteroaryl group, substituted heteroarylalkyl group, substituted alkoxy group, substituted alkylamino group, substituted arylamino group, substituted aralkylamino group, substituted heteroarylamino group, substituted alkylsilyl group, substituted aryl The silyl group and the substituted aryloxy group are hydrogen, deuterium, cyano group, nitro group, halogen group, hydroxy group, alkyl group having 1 to 30 carbon atoms, cycloalkyl group having 1 to 20 carbon atoms, alkenyl group having 2 to 30 carbon atoms, and 2 to 24 carbon atoms. alkynyl group, aralkyl group having 7 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, heteroaryl group having 5 to 60 nuclear atoms, heteroarylalkyl group having 6 to 30 carbon atoms, alkoxy group having 1 to 30 carbon atoms, and 1 carbon atom to 30 alkylamino groups, C6-30 arylamino groups, C6-30 aralkylamino groups, C2-24 heteroarylamino groups, C1-30 alkylsilyl groups, C6-30 arylsilyl groups, and It is substituted with one or more substituents selected from the group consisting of aryloxy groups having 6 to 30 carbon atoms, and when substituted with a plurality of substituents, they are the same as or different from each other.

Specifically, R ₁ to R ₆ are the same as or different from each other, and may be each independently selected from the group consisting of hydrogen, heavy hydrogen, a hydroxyl group, and an alkyl group having 1 to 30 carbon atoms.

More specifically, the photocurable oligomer is a compound represented by Formula 1, and includes both a compound in which A is selected from Formula 2 and a compound in which A is selected from Formula 3.

More specifically, it is a polymer compound to which a photocurable functional group is bound for UV curing, and includes a double bond structure between carbons, and a photocurable action can be exhibited by the carbon-carbon double bond.

In addition, the photocurable oligomer includes a polyurethane structure as a main chain, a photocurable functional group is bonded to the polyurethane structure, and a soft functional group and a hard functional group are included in the compound.

A print may exhibit flexible properties due to the soft functional group included in the photocurable composition, and may exhibit heat resistance due to the hard functional group.

That is, as the photocurable functional group is bonded to the photocurable oligomer and the soft functional group and the hard functional group are used, a flexible effect can be exhibited by using a carbon skeleton having a soft property at room temperature, and a hard property at room temperature. By using the carbon skeleton having a carbon skeleton, it is possible to exhibit a property that is resistant to heat.

As the photocurable oligomer includes a carbon skeleton having a hard property, it is possible to manufacture a 3D printed output having excellent physical properties such as thermal properties, strength, modulus of elasticity and tensile elongation, and which can be restored to its original shape by heat. there is.

In addition, since the photocurable oligomer includes a carbon skeleton having a soft property, the shape can be deformed by an external force after heat is applied.

In general, a composition for a 3D printer includes only a carbon skeleton having a hard property in order to increase the physical properties of an output product, which can increase the physical properties of an output product, but on the contrary, when the shape is deformed by use, the shape Since it cannot be restored, there is a problem that it cannot be used multiple times.

As the composition for a 3D printer in the present invention includes a carbon skeleton having a hard property and a carbon skeleton having a soft property, not only excellent physical properties such as thermal properties, strength, elastic modulus and tensile elongation, but also a soft functional group The flexible property of can be used together, so that if the shape is deformed by an external force in a state where heat is applied, the deformed shape can be fixed, and then when heat is provided again, it is possible to restore the original shape.

As will be described later, the photocurable composition for a 3D printer of the present invention can be used as a transparent orthodontic device, and the transparent orthodontic device is used to straighten teeth to a desired position while being fitted to a patient's teeth. . Accordingly, the transparent orthodontic device output by the 3D printer must exhibit physical characteristics that will not be damaged against the resistance at the current position of the patient's teeth, and must be able to provide force to move the teeth to the position to be corrected. The correction effect and the correction principle of the transparent orthodontic appliance of the present invention will be described later. However, the photocurable composition for 3D printers of the present invention contains both soft functional groups and hard functional groups in the photocurable oligomer, so that it has excellent physical properties and is capable of shape deformation in a state where heat is applied. In addition, it is possible to manufacture a transparent orthodontic appliance having excellent orthodontic power due to the property that it can be restored to its original shape by heat.

In addition, as described above, the photocurable composition additionally includes nano-clay, so that physical properties can be supplemented to exhibit high corrective power.

The reactive monomer is an acrylate-based monomer.

More specifically, the acrylate-based monomer may be selected from the group consisting of a compound represented by Chemical Formula 4, a compound represented by Chemical Formula 5, and a mixture thereof:

[Formula 4]

[Formula 5]

The transparent orthodontic appliance according to another embodiment of the present invention may include the photocurable composition for the 3D printer.

The transparent orthodontic device of the present invention is output by 3D printing using a photocurable composition, and unlike conventional transparent orthodontic devices, it is possible to precisely reproduce the curved surface of teeth, and the orthodontic effect is excellent because of its high adhesion to the teeth. .

The transparent orthodontic device of the present invention is manufactured by obtaining data on the patient's tooth structure and outputting it, and can be manufactured with almost no difference with the tooth structure and deviation of 50 to 80 μm, whereas the conventional transparent orthodontic device The deviation from the patient's teeth appears to be 200 to 300 μm, so the orthodontic force is poor because it cannot be closely adhered to.

The transparent orthodontic device of the present invention is heated to 40 ° C. or higher, and then inserted into the patient's teeth and fixed in shape in close contact with the teeth, and the transparent orthodontic device in close contact with the teeth is restored to its original shape by body temperature to straighten teeth

The transparent orthodontic device of the present invention can be deformed in shape by putting it in and out of heated water. When heat is applied, flexibility appears for a certain period of time, and shape deformation is possible. Using this property, the transparent orthodontic appliance is immersed in water at 60 to 100 ° C. before being inserted into the patient's teeth, then taken out and inserted into the teeth. Then, if you simply press it with your hand, the shape is deformed into a form that closely adheres to the teeth.

Thereafter, when heat is provided to the transparent orthodontic device by body temperature in the oral cavity, restoration to the original output form occurs.

That is, after immersing it in water at 60 to 100 ° C., inserting it into the teeth, and transforming the shape into the same shape as the teeth, the transparent orthodontic device of the present invention is transformed in shape according to the current patient's tooth structure, and then When heat is provided by body temperature, the original output form is gradually restored, and at this time, the transparent orthodontic appliance moves the teeth to the position to be corrected by the force to restore the original shape.

That is, the conventional orthodontic device is manufactured as a transparent orthodontic device according to the position of the tooth to be corrected step by step from information obtained from the patient's tooth structure, and then inserted into the tooth to move the tooth by the nature of the hard material. . As described above, the conventional transparent orthodontic device moves the teeth due to the nature of the material, and does not provide a uniform force within the teeth, so the orthodontic effect is reduced.

On the other hand, as described above, the transparent orthodontic device of the present invention is in a state in which the transparent orthodontic device is deformed to the same structure as the teeth when first used, but when heat is provided by body temperature, the transparent orthodontic device is originally It is restored to the shape of the tooth, and the force transmitted to the tooth is not the force of the material of the orthodontic device, but the force generated and transmitted by the restoration of the shape. provided, and the tooth becomes movable as a whole.

A method for preparing a photocurable composition for a 3D printer according to another embodiment of the present invention includes: 1) mixing and stirring at least one reactive monomer; 2) preparing a first mixture by adding nanoclay to the reactive monomer, pulverizing and dispersing; 3) preparing a second mixture by adding a photocurable oligomer heated in an oven at 50 to 70° C. for 10 to 15 hours into the first mixture; and 4) adding a photoinitiator to the second mixture, mixing, and defoaming.

Step 1) is a step of mixing and stirring a reactive monomer, mixing and stirring a compound represented by Formula 4 and a compound represented by Formula 5 below:

[Formula 4]

[Formula 5]

The reactive monomers are mixed in the same weight ratio and stirred. Thereafter, the nanoclay is added to the mixture in which the reactive monomer is mixed, and pulverized and dispersed to prepare a first mixture.

The first mixture is a form in which nanoclay is uniformly dispersed, and more specifically, a grinding and dispersing process is performed for 30 seconds to 90 seconds at an output of 700 to 800 w using a tip sonicator. When proceeding with a dispersion process other than the above grinding and dispersion process, the nanoclay is not uniformly dispersed and the dispersion stability is deteriorated, so that the first mixture is layer-separated over time. That is, when dispersing by the above dispersing method, it is not only uniformly dispersed, but also exhibits excellent stability.

Thereafter, a photocurable oligomer heated in an oven at 50 to 70° C. for 10 to 15 hours is added to the first mixture to prepare a second mixture. Since the photocurable oligomer has a high viscosity and is difficult to mix at room temperature, it is mixed by heating in an oven.

Finally, a photoinitiator is added and mixed and defoamed using a paste mixer to prepare a photocurable composition.

Specifically, the photoinitiator is a compound represented by Formula 6 below:

[Formula 6]

The photocurable composition may include a photocurable oligomer; reactive monomers; photoinitiators; And in addition to the nano-clay, additives may be included, for example, a leveling agent, a slip agent, or a stabilizer to improve thermal and oxidative stability, storage stability, surface properties, flow properties, and process properties. Conventional additives may be included.

The photocurable composition according to an embodiment of the present invention may include 0.5 to 5 parts by weight of nanoclay and 1 part by weight of a photoinitiator based on 100 parts by weight of the UV resin. The UV resin is a photocurable oligomer of the present invention; and a reactive monomer, more specifically, a compound in which A is selected from Formula 2 among compounds represented by Formula 1 below, a compound in which A is selected from Formula 3 among compounds represented by Formula 1 below, and a compound represented by Formula 4 below The compound and the compound represented by Formula 5 may be included in a weight ratio of 1:1:1:1 to 1:2:1:1:

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

here,

n is an integer from 1 to 1,000;

A is a compound represented by Formula 2 or Formula 3,

* means the part to be combined,

R ₁ to R ₆ are the same as or different from each other, and each independently represents hydrogen, heavy hydrogen, a cyano group, a nitro group, a halogen group, a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted cyclo group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 24 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, A substituted or unsubstituted heteroaryl group having 5 to 60 carbon atoms, a substituted or unsubstituted heteroarylalkyl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, A substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylamino group having 2 to 24 carbon atoms, or a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms , It is selected from the group consisting of a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms and a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms,

The substituted alkylene group, substituted arylene group, substituted heteroarylene group, substituted cycloalkylene group, substituted alkyl group, substituted cycloalkyl group, substituted alkenyl group, substituted alkynyl group, substituted aralkyl group, substituted aryl Group, substituted heteroaryl group, substituted heteroarylalkyl group, substituted alkoxy group, substituted alkylamino group, substituted arylamino group, substituted aralkylamino group, substituted heteroarylamino group, substituted alkylsilyl group, substituted aryl The silyl group and the substituted aryloxy group are hydrogen, deuterium, cyano group, nitro group, halogen group, hydroxy group, alkyl group having 1 to 30 carbon atoms, cycloalkyl group having 1 to 20 carbon atoms, alkenyl group having 2 to 30 carbon atoms, and 2 to 24 carbon atoms. alkynyl group, aralkyl group having 7 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, heteroaryl group having 5 to 60 nuclear atoms, heteroarylalkyl group having 6 to 30 carbon atoms, alkoxy group having 1 to 30 carbon atoms, and 1 carbon atom to 30 alkylamino groups, C6-30 arylamino groups, C6-30 aralkylamino groups, C2-24 heteroarylamino groups, C1-30 alkylsilyl groups, C6-30 arylsilyl groups, and It is substituted with one or more substituents selected from the group consisting of aryloxy groups having 6 to 30 carbon atoms, and when substituted with a plurality of substituents, they are the same as or different from each other.

manufacturing example

The monomers represented by Chemical Formulas 4 and 5 were mixed in a weight ratio of 1:1, sepiolite was added, and then pulverized and dispersed for 1 minute at 750w output using a tip sonicator. Thereafter, the photocurable oligomer having fluidity was mixed by heating in an oven at 60° C. for 12 hours. The photocurable oligomer is a compound represented by Formula 1 below, including both a compound in which A is selected from Formula 2 and a compound in which A is selected from Formula 3, and a compound selected from Formula 2 and a compound selected from Formula 3 in a weight ratio of 1:1.5. Then, a photoinitiator represented by Formula 6 was mixed, and mixed and defoamed using a paste mixer.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

here,

n is an integer from 1 to 1,000;

* means the part to be combined,

R ₁ to R ₆ are methyl groups.

The weight ratio with respect to the photocurable composition is as follows.

composition		sample name	sepiolite
UV resin				photoinitiator
100	One	DLP Sep-0	0
		DLP Sep-0.5	0.5
		DLP Sep-1	One
		DLP Sep-2	2
		DLP Sep-3	3
		DLP Sep-5	5

(Unit by weight) Here, the UV resin includes a photocurable oligomer and a monomer, wherein A in Formula 1 is a compound selected from Formula 2, a compound selected from Formula 3, a monomer represented by Formula 4, and a compound represented by Formula 5 Monomers are included in a weight ratio of 1:1.5:1:1.

Storage stability evaluation

In order to evaluate storage stability due to the dispersion of the monomer and sepiolite, a mixed solution of sepiolite and monomer was stored for 3 days to determine whether layer separation occurred.

The experimental results are shown in FIG. 1 .

From the left, it can be seen that DLP Sep-0.5, DLP Sep-1, DLP Sep-2, DLP Sep-3, and DLP Sep-5 do not cause layer separation even after 3 days and remain stable. Sepiolite is a type of clay, and it is not easy to disperse with monomers, and there is a problem of poor storage stability even after dispersion. However, it was confirmed that, as in the present invention, when the pulverization and dispersion process is performed using the tips sonic equipment, it is not only uniformly dispersed, but also exhibits excellent stability even during long-term storage.

Evaluation of physical properties of output

It was printed in ASTM D638 type No. 5 using a DLP-type 3D printer. First, a specimen was printed using a DLP-type 3D printer, and curing was performed for 10 minutes at an intensity of 400 mW/cm 2 .

The tensile strength of the composite samples was measured using UTM (AllroundLine Z010, Zwick, Germany) to confirm the change in material properties and 3D printing effect as the SEP content and printing method increased. A crosshead speed of 5 mm/min was used during the measurement and the mechanical properties were analyzed at room temperature (RT, ~20 °C). Seven samples of each configuration were measured to calculate the margin of error.

A rheometer (MCR 302, Anton Paar Ltd., Austria) was used to measure the rheological properties of the photocurable composition. The disposable parallel plate had a diameter of 25 mm, an experimental temperature of 25 °C, a plate interval of 100 μm, and a shear rate of 0.1 to 100 rad/s.

The rheological behavior before curing as the content of sepiolite increases is shown in FIG. 5 . As the sepiolite was dispersed, the viscosity of the composition increased, but shear thinning behavior began as the deformation increased.

In the case of a photocurable composition containing 2, 3, and 5 parts by weight of sepiolite, it can be explained by a phenomenon in which viscosity decreases and yield stress occurs as the structure of a nanostructure configured in a stationary state collapses, such as shear thinning. However, in the present invention, the case of including 0, 0.5, and 1 parts by weight of sepiolite exhibits Newtonian fluid behavior, and the above phenomenon is shown in FIG. 4. The photocurable composition without sepiolite contains a large amount of monomers and exhibits Newtonian fluid behavior as only some photoinitiators are present. In addition, although sepiolite is present, when it is included in 0.5 and 1 part by weight, no interference occurs even when both ends of the sepiolite rotate in any direction. However, when the sepiolite particles were included in an amount of 1 part by weight or more, a nanostructure was formed at a moment above a critical value for rheological permeation and aligned under shear force. The photocurable composition comprising 5 parts by weight of sepiolite showed a critical point for entanglement and started to exhibit a clear shear thinning behavior.

Evaluation of yield characteristics of photocurable compositions

6 relates to yield characteristics for the photocurable composition of the present invention. The yield characteristics play an important role in maintaining the shape of the output. However, the photocurable composition for 3D printing of the DLP method must flow in a liquid state. Otherwise, it cannot be printed in the DLP printing environment. Therefore, since the viscosity increases as the content of sepiolite increases, it is necessary to check the yield characteristics.

An important plot of yield characteristics can be seen for samples containing sepiolite at 2, 3 and 5 parts by weight with shear thinning properties. In the case of including 0, 0.5, and 1 part by weight of sepiolite, Newtonian fluid behavior is observed, and the yield properties are meaningless. When included in 2 to 5 parts by weight, both the storage coefficient and the loss coefficient increased as the content of sepiolite increased.

In addition, it was confirmed that the difference between the storage coefficient and the loss coefficient narrowed as the content increased. However, the loss coefficient was maintained higher than the storage coefficient in all samples, and it was confirmed that the photocurable composition existed in a flowing liquid phase when the sepiolite was included in an amount of 5 parts by weight or less.

Evaluation of recovery properties of photocurable compositions

The shear modulus and viscosity of the photocurable composition according to an embodiment of the present invention vary not only by the content of sepiolite but also by shear stress and time, which can be confirmed through FIG. 7 . The correlation between sepiolite content, stress and time is fluid as shown in FIG. 7 . The storage modulus decreases during a shear force of 300 Pa, but recovers at a shear force of 0.5 pa. However, during the test process, the loss coefficient of the sample maintained a higher value than the storage coefficient.

Evaluation of photocuring behavior of photocurable compositions

An MCR 302 rheometer (Anton Paar Ltd., Austria) was used to measure the change in rheological properties during the curing behavior of the photocurable composition. The diameter of the disposable parallel plates is 12 mm, the experimental temperature is 25 °C, the plate spacing is 100 μm, the shear rate is 0.01%, and the radian is 10 rad/s. An LED with a wavelength of 365 nm was used at an intensity of 15 mW/cm ² . For stabilization, the plate was vibrated for 30 seconds, then irradiated for 300 seconds, and at the same time, a force of 0.1 N was applied to measure the degree of shrinkage of the material while moving the plate.

To evaluate the photocuring behavior, the rheological behavior of the material was observed while irradiating with 385 nm UV. 8 is a result of monitoring the storage modulus change of the photocurable composition during the curing process. After stabilizing the composition for 30 seconds, UV irradiation was performed. In general, a photocurable composition to which nanomaterials are added tends to cure slowly because the nanomaterials absorb UV rays. If the photocuring behavior is delayed by sepiolite, a problem of applying different printing conditions for each sample may occur.

However, as shown in FIG. 8, it was confirmed that the composition of the present invention increased the storage modulus of all samples 5 seconds after UV irradiation started.

In addition, it was confirmed that the storage modulus of the material tended to increase as the sepiolite content increased, and based on the above results, sepiolite has good compatibility with UV resin and is effective in structural reinforcement.

Mechanical Tensile Properties of 3D Printed Outputs

Samples for measuring tensile strength were printed using the DLP method and evaluated. Experimental results of the DLP output samples showed that the tensile strength and modulus of elasticity increased as the content of sepiolite increased. At a concentration of 5 parts by weight, the tensile strength increased from 20.7 MPa (control, pure photocurable resin) to 25.6 MPa, and the elastic modulus increased from 210.9 MPa (control, pure photocurable resin) to 346.4 MPa.

In addition, as shown in FIGS. 9 and 10, high elongation was maintained at sample breakage despite an increase in sepiolite content. This phenomenon is presumed to be due to the characteristics of the photocurable oligomer used in this experiment. The high-viscosity oligomer and the monomer for viscosity dilution used in the experiment can respond to structural strengthening and transformation through the interaction of electrical attraction with sepiolite. A typical nanocomposite restricts the movement of molecular chains in a polymer matrix, resulting in increased strength but lower elongation.

On the other hand, the photocurable composition of the present invention can have improved mechanical properties and can change the mechanical properties depending on the purpose and use.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

The present invention relates to a photocurable composition for a 3D printer and a method for producing the same, and more particularly, to a photocurable composition capable of producing an output product using a DLP-type 3D printer and a method for producing the same.

Claims (7)

1. photocurable oligomers;

   reactive monomers;

   photoinitiators; and

   Including nanoclay,

   The nanoclay enhances the mechanical properties of the output printed by 3D printing due to the interaction of the reactive monomer and the electrical attraction

   A photocurable composition for 3D printers.
2. According to claim 1,

   The nano-clay is Sepiolite

   A photocurable composition for 3D printers.
3. According to claim 2,

   The sepiolite is in the form of a single fiber, with an average length of 0.2 to 4 μm, a width of 10 to 30 nm, and an average thickness of 5 to 10 nm.

   A photocurable composition for 3D printers.
4. According to claim 1,

   The photocurable oligomer is a compound represented by Formula 1 below.

   Photocurable composition for 3D printers:

   [Formula 1]

   

   [Formula 2]

   

   [Formula 3]

   

   here,

   n is an integer from 1 to 1,000;

   A is a compound represented by Formula 2 or Formula 3,

   * means the part to be combined,

   R ₁ to R ₆ are the same as or different from each other, and each independently represents hydrogen, heavy hydrogen, a cyano group, a nitro group, a halogen group, a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted cyclo group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 24 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, A substituted or unsubstituted heteroaryl group having 5 to 60 carbon atoms, a substituted or unsubstituted heteroarylalkyl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, A substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylamino group having 2 to 24 carbon atoms, or a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms , It is selected from the group consisting of a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms and a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms,

   The substituted alkylene group, substituted arylene group, substituted heteroarylene group, substituted cycloalkylene group, substituted alkyl group, substituted cycloalkyl group, substituted alkenyl group, substituted alkynyl group, substituted aralkyl group, substituted aryl Group, substituted heteroaryl group, substituted heteroarylalkyl group, substituted alkoxy group, substituted alkylamino group, substituted arylamino group, substituted aralkylamino group, substituted heteroarylamino group, substituted alkylsilyl group, substituted aryl The silyl group and the substituted aryloxy group are hydrogen, deuterium, cyano group, nitro group, halogen group, hydroxy group, alkyl group having 1 to 30 carbon atoms, cycloalkyl group having 1 to 20 carbon atoms, alkenyl group having 2 to 30 carbon atoms, and 2 to 24 carbon atoms. alkynyl group, aralkyl group having 7 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, heteroaryl group having 5 to 60 nuclear atoms, heteroarylalkyl group having 6 to 30 carbon atoms, alkoxy group having 1 to 30 carbon atoms, and 1 carbon atom to 30 alkylamino groups, C6-30 arylamino groups, C6-30 aralkylamino groups, C2-24 heteroarylamino groups, C1-30 alkylsilyl groups, C6-30 arylsilyl groups, and It is substituted with one or more substituents selected from the group consisting of aryloxy groups having 6 to 30 carbon atoms, and when substituted with a plurality of substituents, they are the same as or different from each other.
5. According to claim 1,

   The reactive monomer is an acrylate-based monomer

   A photocurable composition for 3D printers.
6. Claims 1 to 5 comprising a photo-curable composition for a 3D printer

   Transparent orthodontic appliance.
7. 1) mixing and stirring at least one reactive monomer;

   2) preparing a first mixture by adding nanoclay to the reactive monomer, pulverizing and dispersing;

   3) preparing a second mixture by adding a photocurable oligomer heated in an oven at 50 to 70° C. for 10 to 15 hours into the first mixture; and

   4) adding a photoinitiator to the second mixture, mixing and defoaming

   A method for producing a photocurable composition for 3D printers.

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