KR102176233B1 - Composition for 3 dimensional printing - Google Patents

Abstract

The present application relates to a resin composition for 3D printing, a 3D printing method using the same, and a three-dimensional shape including the same, which precisely forms a three-dimensional three-dimensional shape, and enables the three-dimensional shape to be maintained during curing of the three-dimensional shape. , It provides a resin composition for 3D printing that can realize the uniform cured physical properties of the cured three-dimensional shape.

Description

Composition for 3D printing {COMPOSITION FOR 3 DIMENSIONAL PRINTING}

The present application relates to a resin composition for 3D printing, a 3D printing method using the same, and a three-dimensional shape including the same.

The present application relates to a resin composition that can be applied to 3D printing. A three-dimensional printer has a three-dimensional printing mechanism that is configured to form a physical object in three dimensions. As an ink for 3D printing that allows such a 3D printer to form a physical object in 3D, research on a resin composition for 3D printing is ongoing.

Existing 3D printing methods have been carried out by curing the resin composition with heat or light to realize a desired pattern or three-dimensional shape. However, in the case of the thermosetting type of these methods, the manufacturing process is relatively simple, in which a polymer filament is thermally melted and extruded, dropped one by one at a designated point, and laminated one by one, but provides an inaccurate shape and heat. There are problems such as non-uniform curing problem due to the equipment to be used, phase separation between organic/inorganic composite materials of the composition, and heat shrinkage due to heating/cooling. In addition, in the case of the photo-curing type, precise expression is possible, but there are problems such as the size of the equipment and low hardness after storage and curing.

The present application relates to a composition used as an ink for a 3D printer, which precisely forms a three-dimensional shape, enables the shape of a three-dimensional shape to be maintained during curing of the three-dimensional shape, and uniform curing of the cured three-dimensional shape. It provides a resin composition for 3D printing that can implement physical properties.

The present application relates to a composition for 3D printing. The composition for 3D printing may be applied to, for example, printing a 3D physical object to form a three-dimensional shape. In addition, the resin composition can be applied to sealing electronic devices. For example, the composition can be applied to encapsulating a microelectronic device, for example a microbattery.

An exemplary composition for 3D printing may include a thermosetting resin, magnetic particles, and inorganic particles. The inorganic particles may be included in an amount of 10 to 250 parts by weight based on 100 parts by weight of magnetic particles. In another example, the inorganic particles are 15 to 240 parts by weight, 23 to 230 parts by weight, 40 to 225 parts by weight, 80 to 220 parts by weight, 90 to 215 parts by weight, 110 to 210 parts by weight based on 100 parts by weight of the magnetic particles Parts or 150 to 208 parts by weight may be included. In the present application, by including inorganic particles of a specific weight part or more relative to 100 parts by weight of magnetic particles, the applied three-dimensional shape can be excellently maintained even at high temperatures such as a curing process, and the composition is ferrofluid when an alternating magnetic field to be described later is applied. As described above, the problem of being drawn into the magnetic field applying unit (coil) can be prevented, and the dispersibility of the magnetic particles in the composition can be improved to prevent the magnetic particles from sedimentation. In addition, in the present application, by adjusting the content of the inorganic particles to a specific weight part or less relative to 100 parts by weight of the magnetic particles, they are mixed in an appropriate ratio in relation to the magnetic particles to realize excellent coating properties and uniform curing properties. Accordingly, in the present application, a three-dimensional shape can be precisely formed through 3D printing, the shape can be excellently maintained even at high temperature when the three-dimensional shape is cured, and uniform curing properties can be obtained after the three-dimensional shape is cured.

In the specific example of the present application, the inorganic particles may have a particle diameter in the range of 5 to 20 nm. In the present application, by adjusting the particle diameter range of the inorganic particles, it is possible to have the ability to maintain a shape at a desired level during 3D printing. The inorganic particles may be, for example, non-polar particles, but are not limited thereto. The present application may include inorganic particles as non-polar particles, considering that the resin composition for 3D printing includes magnetic particles and inorganic particles together. For example, in the case of an inorganic particle into which a polar functional group is introduced, compatibility with the magnetic material particles is poor, and thus, when contained in a certain amount or more, dispersibility in the composition decreases, and accordingly, coating properties and curing properties may decrease.

In one example, the inorganic particles may be hydrophobic fuming particles. The hydrophobic fuming particles may be obtained by introducing siloxane, silazane, or alkoxy silane onto the surface of the inorganic particles. In another example of the present application, the inorganic particles may be carbon crystals. In a specific example of the present application, the hydrophobic fumed particles may include hydrophobic fumed silica, and the carbon crystal may include carbon nanotubes, but the present invention is not limited thereto. The carbon nanotubes may have an aspect ratio of 10 or more, 10 to 500, 10 to 400, 50 to 300, 70 to 200, or 80 to 150. In the present specification, the term "aspect ratio" may mean a ratio of a length to a diameter of a particle. By including the inorganic particles, the present application can accurately form a three-dimensional shape through 3D printing, maintain excellent shape even at high temperatures when curing the three-dimensional shape, and have excellent curing properties after the three-dimensional shape is cured. .

In one example, when the inorganic particles are carbon nanotubes, the carbon nanotubes are 5 to 90 parts by weight, 8 to 88 parts by weight, 12 to 83 parts by weight, or 18 to 78 parts by weight based on 100 parts by weight of the magnetic particles. May be included as wealth. In addition, when the inorganic particles are hydrophobic fuming particles, the hydrophobic fuming particles are 15 to 240 parts by weight, 23 to 230 parts by weight, 40 to 225 parts by weight, 80 to 220 parts by weight, 90 to 100 parts by weight of the magnetic particles. It may be included in 215 parts by weight, 110 to 210 parts by weight, or 150 to 208 parts by weight. The present application controls the content of the inorganic particles in the above range according to the material of the inorganic particles, so that the viscosity of the composition is in an appropriate range to be suitable for 3D printing, thereby simultaneously improving the dispersibility, ease of application, and shape retention of the composition. .

The composition for 3D printing of the present application may have a thixotropic index of 2 to 20, 3 to 18, 4 to 15, 5 to 14, or 6 to 13. The present application can provide excellent application characteristics during 3D printing and excellent maintenance of a three-dimensional shape after application by adjusting the thixotropic index of the composition within the above range. In the present application, the thixotropic index may be calculated by the following general formula 1.

[General Formula 1]

T = V _0.5 / V ₅

In the general formula 1, V _0.5 is the viscosity of the composition measured at a temperature of 25 °C and a shear rate of 0.5 / s, V ₅ is the viscosity of the composition measured at a temperature of 25 °C and a shear rate of 5 / s Represents. The measurement is measured within any one shear rate range of 0.01/s to 500/s, and the thixotropic index can be measured by selecting a viscosity value at each of 0.5/s and 5/s.

Meanwhile, in the present specification, the term "thixotropic" may mean a property of having fluidity when the composition is stationary and has no fluidity, but when a shear force is applied. The method of measuring the thixotropic index is not particularly limited, and may be measured using a rheological property measuring device known in the art, and for example, a stress-controlled type rheometer may be used.

In one example, the composition for 3D printing has a viscosity of 3000 cps to 1500000 cps, 7000 cps to 1450000 cps, 11000 cps to 1400000 cps, 12000 cps to 1350000 cps or 13000 cps at a temperature of 25° C. and a shear rate of 0.5/s. To 1300000 cps. In addition, the composition for 3D printing has a viscosity of 800 cps to 150000 cps, 1000 cps to 145000 cps, 1100 cps to 140000 cps, 1500 cps to 130000 cps or 1600 cps to 120000 cps at a temperature of 25° C. and a shear rate of 5/s. It can be within the range of. The present application is to control the thixotropic index of the composition for 3D printing, the viscosity at a shear rate of 0.5/s, and/or the viscosity at a shear rate of 5/s, within the above-described range, so that 3D printing can be performed without clogging the nozzle during application. Process efficiency can be improved and the ability to maintain the shape of a three-dimensional shape after application can be excellently implemented.

In the specific example of the present application, the composition for 3D printing may include magnetic particles, as described above. The magnetic material particles may have two or more multi-magnetic domains. In addition, when the magnetic material particles do not have an external magnetic field, their magnetic domains are irregularly arranged and may be magnetized by an external alternating magnetic field. In the above, the meaning that the magnetic domains are arranged irregularly may mean a state in which the magnetic directions present in the magnetic domains are different and not aligned, and in this case, the net value of magnetization at room temperature may be 0, which may be a state without magnetism. However, when an external magnetic field is applied, the magnetic direction of the magnetic domain is aligned and thus the magnetic particles may be magnetized. The magnetic particles may be super-paramagnetic particles, but are not limited thereto. In the 3D printing method according to the present application, the composition is three-dimensionally applied to form a three-dimensional shape, and vibration heat is generated from the magnetic particles through the application of a magnetic field, thereby uniformly curing the entire thermosetting resin.

Among the existing 3D printing methods, there is a method of curing or sintering the resin using a technology that generates heat by inducing electromagnetic or radiating microwaves by adding metal or conductive material (carbon, carbon nanotube). In some cases, there may be a problem in the physical properties of the resin after curing due to a temperature difference between the contact surface and the inside, and in the case of microwaves, there is a risk of exposure to the human body during replacement work during the process.

The present application generates heat by vibrating by magnetization reversal of magnetic particles through electromagnetic induction heating, and the thermosetting resin may be cured with heat generated accordingly. In the case of a conventional technique for generating heat by electromagnetic induction, heat is generated by an eddy current, which is generated by hysteresis loss of a metal or a magnetic material. However, in the case of the present application, as the particles of the magnetic material become smaller and become nano-sized, the hysteresis loss of the magnetic material itself decreases, and only a saturation magnetization value exists. For this reason, the present application may generate heat due to vibration between magnetic bodies other than eddy currents. In other words, in this application, the magnetic body itself vibrates by the coercive force of the magnetic material particles under an external magnetic field, and the thermosetting resin can be cured using the heat generated at this time, and the curing proceeds from the inside of the composition. It can have physical properties. Accordingly, the present application can implement uniform and stable curing.

As described above, the magnetic material particles may include two or more magnetic domains. In this specification, the term “magnetic domain” generally refers to a region in which magnetization directions are divided differently within a magnetic body. In the present application, magnetic particles having two or more magnetic domains are strongly magnetized by an external alternating magnetic field to generate vibrational heat, and when the magnetic field is removed, it returns to its original state, thereby providing magnetic particles with low residual magnetization of hysteresis loss. have.

In one example, the magnetic particles may have a coercive force of 1 to 200 kOe, 10 to 150 kOe, 20 to 120 kOe, 30 to 100 kOe 40 to 95 kOe, or 50 to 95 kOe. In the present specification, the term "coercive force" may mean the intensity of a critical magnetic field required to reduce the magnetization of a magnetic material to zero. More specifically, a magnetic body magnetized by an external magnetic field maintains a certain degree of magnetization even if the magnetic field is removed, and the strength of the magnetic field that can make the magnetization degree zero by applying a magnetic field in the opposite direction to the magnetized magnetic body is called coercivity. do. The coercive force of a magnetic material may be a criterion for classifying a soft magnetic material or a hard magnetic material, and the magnetic material particles of the present application may be a soft magnetic material. In this application, by controlling the coercive force of the magnetic particles within the above range, it is possible to more easily implement the magnetic conversion of the magnetic material, thereby generating vibrational heat of the desired degree in this application, thereby satisfying the curing properties of the desired degree by uniform curing of the resin. have.

In one example, when the measured value for the physical property value measured in the present application is a value that fluctuates by temperature, the measured temperature may be room temperature, for example, 25°C.

In addition, in one example, the magnetic particles have a saturation magnetization value of 20 to 150 emu/g, 30 to 130 emu/g, 40 to 100 emu/g, 50 to 90 emu/g, or 60 to 85 emu/g at 25°C. There may be. In the present application, the saturation magnetization value of the magnetic particles can be relatively largely controlled, and by generating heat due to vibrations between magnetic particles other than the eddy current, the curing properties can be satisfied by uniform curing of the resin. In the present application, the measurement of the physical properties of magnetic particles may be calculated using a value of a Vibrating Sample Magnetometer (VSM). VSM records the applied magnetic field applied by the Hall probe and the magnetization value of the sample is a device that measures the magnetization value of the sample by recording the electromotive force obtained when vibration is applied to the sample according to Faraday's law. Faraday's law is that if you push the N pole of a bar magnet toward the coil and push it toward the coil, the galvanometer moves and the current flows through the coil. The current resulting from this is called an induced current and is said to be made by induced electromotive force. VSM is a method of measuring the magnetization value of the sample by detecting the induced electromotive force generated when vibration is applied to the sample by this basic operating principle by the search coil. The magnetic properties of a material can be measured simply as a function of magnetic field, temperature, and time, and a magnetic force of up to 2 Tesla and a quick measurement in the temperature range of 2 K to 1273 K are possible.

In a specific example of the present application, the average particle diameter of the magnetic particles may be in the range of 20nm to 300nm, 30nm to 250nm, 40nm to 230nm, or 45nm to 220nm. In addition, the average size of the magnetic domains of the magnetic particles may be in the range of 10 to 50 nm or 20 to 30 nm. In the present application, the number of magnetic domains of the magnetic particles and the size of the coercive force are controlled within the particle diameter range to an appropriate range, thereby generating heat for uniform curing of the resin in the composition. In this application, by controlling the size of the particles to 20 nm or more, it is possible to generate sufficient vibrational heat when curing through a low coercive force and a plurality of magnetic domains, and by controlling it to 300 nm or less, the saturation magnetization value (saturation) while reducing the hysteresis loss of the magnetic body itself magnetization value), and thus uniform and stable curing can be achieved.

As long as the magnetic particles of the present application can generate heat through electromagnetic induction heating, the material is not particularly limited. In one example, the magnetic particles may satisfy Formula 1 below.

[Formula 1]

MX _a O _b

In Formula 1, M is a metal or a metal oxide, X includes Fe, Mn, Co, Ni or Zn, |a × c| = |b × d| is satisfied, where c is the cation charge of X, and d is the anion charge of oxygen. In one example, M may be Fe, Mn, Mg, Ca, Zn, Cu, Co, Sr, Si, Ni, Ba, Cs, K, Ra, Rb, Be, Li, Y, B, or oxides thereof. have. For example, when X _a O _b is Fe ₂ O ₃ , c may be +3 and d may be -2. In addition, for example, when X _a O _b is Fe ₃ O ₄ , it may be expressed as FeOFe ₂ O ₃ , so c may be +2 and +3, and d may be -2. The magnetic particles of the present application are not particularly limited as long as they satisfy Formula 1, and may be, for example, MFe ₂ O ₃ .

In one example, the 3D printing composition of the present application may include magnetic particles alone, or a mixture of the compound of Formula 1 or a compound doped with an inorganic substance in the compound of Formula 1. The inorganic material may include monovalent to trivalent cationic metals or oxides thereof, and two or more types of a plurality of cationic metals may be used.

In one example, the magnetic particles may include those subjected to surface treatment on the surface of the particles. That is, the composition of the present application may include particles surface-treated with a metal, metal oxide, organic material or inorganic material on the surface of the magnetic material particle. The present application may prevent the magnetic material particles from losing the coercive force of the magnetic material due to oxidation in the air through the surface treatment. In addition, the surface treatment may increase compatibility with a filler, a dispersant organic solvent, and the like, which will be described later, and improve dispersibility of the composition. In one example, in the surface treatment, a polymer of polymethyl methacrylate (PMMA) may be formed on the surface by attaching a methyl methacrylate (MMA) monomer to magnetic particles having a carboxyl group on the surface. In addition, the surface of the magnetic particles may be acid-treated to remove the oxide film on the surface, and the surface may be treated, and the surface treatment may also be performed through a method of coating silica particles.

In the specific example of the present application, the magnetic material particles may form a magnetic material cluster. The nanoparticle-sized magnetic material forms a nano cluster, thereby preventing aggregation between the magnetic materials and improving dispersibility, thereby effectively curing the resin by vibrating heat.

In a specific example of the present application, the magnetic particles may be included in an amount of 0.01 to 25 parts by weight, 0.1 to 20 parts by weight, 1 to 15 parts by weight, 3 to 13 parts by weight, or 5 to 12 parts by weight based on 100 parts by weight of the thermosetting resin. In the present specification, unless otherwise specified, the unit "parts by weight" means a weight ratio between each component. By controlling the content of the magnetic particles in the weight ratio, the present application can cure the composition through sufficient heat during 3D printing, and uniformly cure the composition without phase separation.

In one example, the 3D printing composition of the present application may include a curable compound. The curable compound may be a thermosetting resin. The term "thermosetting resin" refers to a resin that can be cured through an appropriate application of heat or an aging process.

In the present application, the specific type of the thermosetting resin is not particularly limited as long as it has the above-described characteristics. In one example, the thermosetting resin may include at least one thermosetting functional group. For example, as one that may be cured to exhibit adhesive properties, it may include one or more thermosetting functional groups such as an epoxy group, a glycidyl group, an isocyanate group, a hydroxy group, a carboxyl group, or an amide group. In addition, specific types of resins as described above may include acrylic resins, polyester resins, isocyanate resins, ester resins, imide resins, or epoxy resins, but are not limited thereto.

In the present application, as the thermosetting resin, aromatic or aliphatic; Alternatively, a linear or branched epoxy resin may be used. In the exemplary embodiment of the present application, an epoxy resin containing two or more functional groups and having an epoxy equivalent of 180 g/eq to 1,000 g/eq may be used. By using an epoxy resin having an epoxy equivalent in the above range, properties such as adhesion performance and glass transition temperature of the cured product can be effectively maintained. Examples of such epoxy resins include cresol novolac epoxy resin, bisphenol A type epoxy resin, bisphenol A type novolac epoxy resin, phenol novolac epoxy resin, tetrafunctional epoxy resin, biphenyl type epoxy resin, triphenol methane type Epoxy resins, alkyl-modified triphenol methane epoxy resins, naphthalene-type epoxy resins, dicyclopentadiene-type epoxy resins, or dicyclopentadiene-modified phenol-type epoxy resins.

In the present application, preferably, an epoxy resin including a cyclic structure in the molecular structure may be used, and more preferably, an epoxy resin including an aromatic group (eg, a phenyl group) may be used. When the epoxy resin contains an aromatic group, the cured product may have excellent thermal and chemical stability. Specific examples of the aromatic group-containing epoxy resin that can be used in the present application include biphenyl-type epoxy resins, dicyclopentadiene-type epoxy resins, naphthalene-type epoxy resins, dicyclopentadiene-modified phenol-type epoxy resins, cresol-based epoxy resins, Bisphenol-based epoxy resin, xylog-based epoxy resin, polyfunctional epoxy resin, phenol novolac epoxy resin, triphenolmethane-type epoxy resin, and alkyl-modified triphenolmethane epoxy resin may be one or more mixtures, but is limited thereto. no.

In the above, as described above, the composition for 3D printing may further include a thermosetting agent. For example, a curing agent capable of forming a crosslinked structure or the like by reacting with the thermosetting resin may be further included.

An appropriate type of curing agent may be selected and used depending on the type of functional group contained in the resin.

In one example, when the thermosetting resin is an epoxy resin, the curing agent is a curing agent for an epoxy resin known in the art, for example, an amine curing agent, an imidazole curing agent, a phenol curing agent, a phosphorus curing agent or an acid anhydride curing agent. One or more types may be used, but the present invention is not limited thereto.

In one example, as the curing agent, an imidazole compound having a solid state at room temperature and a melting point or decomposition temperature of 80° C. or higher may be used. Such compounds include, for example, 2-methyl imidazole, 2-heptadecyl imidazole, 2-phenyl imidazole, 2-phenyl-4-methyl imidazole, or 1-cyanoethyl-2-phenyl imidazole. This may be illustrated, but is not limited thereto,

The content of the curing agent may be selected according to the composition of the composition, for example, the type or ratio of the thermosetting resin. For example, the curing agent may be included in an amount of 1 to 20 parts by weight, 1 to 10 parts by weight, or 1 to 8 parts by weight, based on 100 parts by weight of the thermosetting resin. However, the weight ratio may be changed according to the type and ratio of the functional group of the thermosetting resin, or the crosslinking density to be implemented.

In addition, in one example, the 3D printing composition may further include a dispersant so that the magnetic particles can be uniformly dispersed. As the dispersant that can be used here, for example, a surfactant having affinity with the surface of the magnetic particles and having good compatibility with a thermosetting resin, for example, a nonionic surfactant, etc. may be used. In addition, as a dispersant, a type containing an acid or a basic group, a high molecular weight acrylic polymer type with a weight average molecular weight of 10,000 or more, an inorganic soda type, a metal salt type dispersant, etc. may be exemplified, and the composition of the present application is one or more dispersants. It may include. The dispersant may be included in an amount of 0.01 to 10 parts by weight, 0.1 to 8 parts by weight, or 0.15 to 5 parts by weight based on 100 parts by weight of the thermosetting resin.

In addition to the above-described configuration, the composition for 3D printing according to the present application may contain various additives according to the use, the type of thermosetting resin, and the 3D printing process to be described later within a range that does not affect the effects of the above-described invention. For example, the resin composition may contain a coupling agent, a crosslinking agent, a curable material, a tackifier, an ultraviolet stabilizer, or an antioxidant in an appropriate range depending on the desired physical properties. Here, the curable material may refer to a material having a thermosetting functional group and/or an active energy ray-curable functional group separately included in addition to the components constituting the above-described composition.

The present application also relates to a 3D printing method. An exemplary 3D printing method may include forming a three-dimensional shape by three-dimensionally applying the above-described composition. In the 3D printing method according to the present application, after applying the composition three-dimensionally to form a three-dimensional shape, vibration heat is generated from the magnetic particles through a magnetic field application step, and accordingly, the thermosetting resin can be uniformly cured.

The step of applying the magnetic field is not particularly limited, and may be performed by a known method by a person skilled in the art. The alternating magnetic field may be applied with an intensity within a range of, for example, 0.001 to 0.5 Tesla (Wb/m ² ). In another example, the magnitude of the applied alternating magnetic field may be 0.45 Tesla or less, 0.4 Tesla or less, 0.35 Tesla or less, 0.3 Tesla or less, 0.25 Tesla or less, or 0.2 Tesla or less. In another example, the strength of the alternating magnetic field may be about 0.002 Tesla or more, about 0.003 Tesla or more, or about 0.004 Tesla or more.

The alternating magnetic field can be performed by applying, for example, at a frequency of about 50 kHz to 1,000 kHz. The frequency may be 900 kHz or less, 800 kHz or less, 700 kHz or less, 600 kHz or less, 500 kHz or less, or 450 kHz or less, in another example. The frequency may be about 70 kHz or more, about 100 kHz or more, about 150 kHz or more, about 200 kHz or more, or about 250 kHz or more, in another example.

The application of the alternating magnetic field may be performed within a range of, for example, about 5 seconds to 10 hours. The application time is, in another example, about 9 hours or less, about 8 hours or less, about 7 hours or less, about 6 hours or less, about 5 hours or less, about 4 hours or less, about 3 hours or less, about 2 hours or less, about It may be 1 hour or less, about 50 minutes or less, about 40 minutes or less, about 30 minutes or less, about 20 minutes or less, about 15 minutes or less, about 10 minutes or less, or about 5 minutes or less.

The above-mentioned heating conditions, for example, an applied alternating magnetic field, frequency, and application time may be changed in consideration of the amount of heat required for curing of the curable composition, the type and ratio of particles, and the like, as described above.

The curing of the composition for 3D printing may be performed only by applying a magnetic field as described above, or, if necessary, may be performed while applying appropriate heat together with the application of the induction heating, that is, an alternating magnetic field.

The present application also relates to a three-dimensional three-dimensional shape. The three-dimensional shape may include a cured product of the composition for 3D printing described above.

The present application also relates to a microelectronic device. An exemplary microelectronic device may include a cured product containing the above-described composition. The cured product may be applied as a sealing material, but is not limited thereto. For example, the microelectronic device may include a microbattery, a biosensor, or an actuator. In addition, the present application may provide a display device using the above-described composition as a sealing material.

The present application provides a resin composition for 3D printing capable of accurately forming a three-dimensional three-dimensional shape, allowing the three-dimensional shape to be maintained during curing of the three-dimensional shape, and realizing uniform curing properties of the cured three-dimensional shape. do.

Hereinafter, the present invention will be described in more detail through examples according to the present invention and comparative examples not according to the present invention, but the scope of the present invention is not limited by the examples presented below.

Example One

In the container, as magnetic particles, soft magnetic FeOFe ₂ O ₃ particles (Multi-Magnetic Domains, average particle diameter of about 50 nm: measured by Field Emission Scanning Electron Microscope (using DLS)), carbon nanotubes as inorganic particles (aspect ratio) 100), a bisphenol A (BPA) type epoxy resin as a thermosetting resin and an imidazole-based curing agent of Shikoku Chemical C11ZA as a curing agent, respectively, were 5:5:90:5 (FeOFe ₂ O ₃ :carbon nanotube: epoxy resin: C11ZA) A resin composition was prepared by mixing in a weight ratio, and a three-dimensional shape was formed through the resin composition.

Example 2 to 17

A resin composition was prepared in the same manner as in Example 1, except that each component was added in the weight ratio of Table 1, and a three-dimensional shape was formed.

Comparative example 1 to 2

A resin composition was prepared in the same manner as in Example 1, except that each component was added in the weight ratio of Table 1, and a three-dimensional shape was formed.

Thermosetting resin Magnetic particles Hardener Inorganic particles Suzy 1 Suzy2 #One #2 #3 #4 #5 Example 1 90 5 5 5 Example 2 92 5 5 3 Example 3 94 5 5 One Example 4 85 5 5 10 Example 5 90 5 5 5 Example 6 94 5 5 One Example 7 85 5 5 10 Example 8 90 5 5 5 Example 9 94 5 5 One Example 10 90 5 5 5 Example 11 90 5 5 5 Example 12 85 5 5 10 Example 13 90 5 5 5 Example 14 94 5 5 One Example 15 85 5 5 10 Example 16 90 5 5 5 Example 17 94 5 5 One Comparative Example 1 95 5 5 Comparative Example 2 95 5 5 Resin 1: BPA type epoxy resin (about 6,000 cps viscosity)
Resin 2: BPA type epoxy resin (about 300 cps viscosity)
Magnetic particles: FeOFe ₂ O ₃ particles (Multi-Magnetic Domains, average particle diameter of about 50 nm: measured by Field Emission Scanning Electron Microscope (using DLS))
Inorganic particle #1: carbon nanotube (aspect ratio of 100)
Inorganic particle #2: fumed silica into which polydimethylsiloxane is introduced
Inorganic particle #3: hydrophilic fumed silica into which a polar functional group is introduced (AEROSIL 200)
Inorganic particle #4: fumed silica into which hexamethyldisilazane is introduced
Inorganic particle #5: colloidal silica into which hexamethyldisilazane is introduced
Hardener: Shikoku Chemical C11ZA imidazole hardener

Experimental example 1-viscosity and Thixotropic Index measurement

The thixotropic index was measured through the following General Formula 1 for the composition for 3D printing prepared in Examples and Comparative Examples.

[General Formula 1]

T = V _0.5 / V ₅

In the general formula 1, V _0.5 is the viscosity of the composition measured at a temperature of 25 °C and a shear rate of 0.5 / s, V ₅ is the viscosity of the composition measured at a temperature of 25 °C and a shear rate of 5 / s Represents.

The viscosity was measured in a shear rate range of 0.01/s to 500/s at 25° C. using a stress-controlled type rheometer.

Experimental example 2-3D printing application characteristics evaluation

The composition for 3D printing prepared in Examples and Comparative Examples was passed through a nozzle of a supply device, a square having a line width of 1 mm was applied on the support, and cured by applying an alternating magnetic field. The AC magnetic field was placed 0.5 mm above the solenoid coil (3 turns, OD 25 mm, ID 20 mm) from the three-dimensional shape, and applied for 3 minutes at an intensity of 0.05T using a magnetic field generator (Ambrell's Easyheat). The resin composition is thermally cured with vibrational heat generated through the application of the magnetic field to form a pattern or a three-dimensional shape, and when a three-dimensional shape is formed within an error range of ±10 μm from the desired shape, the composition is moved toward the coil when the magnetic field is applied. When the composition is partially attracted or spreads by the generation of heat, exceeding the error range of ±10㎛, but within the error range of ±15㎛ △, when the magnetic field is applied, the composition is attracted to the coil or the composition is spread by the generation of heat. When the error range of ±15㎛ is exceeded, it is marked with X.

Experimental example 3-dispersibility evaluation

For 3D printing compositions prepared in Examples and Comparative Examples, 5 mL of the composition was put in a container, and when phase separation occurred after 15 days, X, when phase separation occurred after 30 days, △, 30 days If the phase was not separated after passing, it was classified as O.

Viscosity at 0.5/s (cps) Viscosity at 5/s (cps) Thixotropic
Indices Application characteristics evaluation Dispersibility
evaluation Example 1 - - N/A △ △ Example 2 998,114 91,570 10.9 O O Example 3 561,147 82,280 6.82 O O Example 4 421,423 33,183 12.7 O O Example 5 287,942 29,144 9.88 O O Example 6 112,498 27,239 4.13 △ O Example 7 183,481 30,428 6.03 O X Example 8 164,779 29,010 5.68 O X Example 9 131,934 25,226 5.23 △ △ Example 10 236,842 27,733 8.54 O O Example 11 11,640 9,620 1.21 △ X Example 12 26,244 2,548 10.3 O O Example 13 13,368 1,792 7.46 O O Example 14 3,315 1,180 2.81 △ O Example 15 6,147 1,260 4.88 △ X Example 16 4,601 1,117 4.12 △ X Example 17 3,701 1,048 3.53 △ △ Comparative Example 1 10,016 9,449 1.06 X △ Comparative Example 2 613 595 1.03 X X

As shown in Table 2, in Comparative Examples 1 and 2, which did not contain inorganic particles, the coating properties were very poor as the composition was drawn toward the coil when the magnetic field was applied or the composition was spread by the generation of heat.

Claims (20)

A composition for 3D printing comprising a thermosetting resin, magnetic particles in the range of 0.01 to 25 parts by weight based on 100 parts by weight of the thermosetting resin, and 10 to 250 parts by weight of inorganic particles based on 100 parts by weight of the magnetic particles. The composition for 3D printing according to claim 1, wherein the particle diameter of the inorganic particles is in the range of 5 to 20 nm. The composition for 3D printing according to claim 1, wherein the inorganic particles are non-polar particles. The composition for 3D printing according to claim 1, wherein the inorganic particles are hydrophobic fuming particles. The composition for 3D printing according to claim 4, wherein the hydrophobic fuming particles are siloxane, silazane, or alkoxy silane introduced on the surface of the inorganic particles. The composition for 3D printing according to claim 1, wherein the inorganic particles comprise hydrophobic fumed silica or carbon nanotubes. The composition for 3D printing according to claim 6, wherein the carbon nanotubes have an aspect ratio of 10 or more. The composition of claim 1, wherein the magnetic particles have two or more magnetic domains, and when there is no external magnetic field, the magnetic domains are irregularly arranged and magnetized by an external alternating magnetic field. The composition for 3D printing according to claim 1, wherein the magnetic particles have a coercive force in the range of 1 to 200 kOe. The composition for 3D printing according to claim 1, wherein the magnetic particles have a saturation magnetization value of 20 to 150 emu/g at 25°C. The composition for 3D printing according to claim 1, wherein the magnetic particle has a particle diameter of 20 to 300 nm. The composition for 3D printing according to claim 1, wherein the magnetic material particles form a magnetic material cluster. The composition for 3D printing according to claim 1, wherein the magnetic particles are vibrated by magnetic conversion. The composition for 3D printing according to claim 1, wherein the thermosetting resin comprises at least one thermosetting functional group. The composition for 3D printing according to claim 14, wherein the thermosetting functional group comprises an epoxy group, a glycidyl group, an isocyanate group, a hydroxy group, a carboxyl group, or an amide group. The composition for 3D printing according to claim 1, further comprising a thermosetting agent. The composition for 3D printing according to claim 16, wherein the thermal curing agent comprises an amine curing agent, an imidazole curing agent, a phenol curing agent, a phosphorus curing agent or an acid anhydride curing agent. A 3D printing method comprising the step of forming a three-dimensional shape by applying the composition for 3D printing of claim 1. 19. The 3D printing method of claim 18, further comprising the step of applying a magnetic field to the applied composition. A three-dimensional shape comprising a cured product of the composition for 3D printing of claim 1.