Transparent photosensitive resin for DLP 3D printing and preparation method thereof

Abstract

The invention discloses transparent photosensitive resin for DLP 3D printing and a preparation method of the transparent photosensitive resin. The transparent photosensitive resin for DLP 3D printing comprises the following components in percentage by weight: 40%-60% of tetrahydrofuran acrylate, 20%-30% of bifunctional polyurethane acrylate, 19.5%-29.5% of a reactive diluent, 0.02%-0.03% of a light absorber, 0.2%-0.3% of a photoinitiator Irgacure-2959, 0.1%-0.3% of a defoaming agent and 0.1%-0.3% of a flatting agent, and the transparent photosensitive resin for DLP 3D printing is prepared by fully stirring and mixing the components at room temperature. The photosensitive resin for DLP 3D printing is transparent, low in viscosity and high in product speed, and the rapid formability of a 3D printing product is guaranteed; after curing, the volume shrinkage change is small, and the dimensional stability of the product is high; the mechanical property is stable, and the anti-aging property is excellent.

Description

Technical Field

[0001] The invention belongs to the field of photosensitive resins and relates to a transparent photosensitive resin for DLP 3D printing and a preparation method thereof. Background Art

[0002] 3D printing is a rapid prototyping technology that has been developed recently. Due to its high performance, complexity, refinement and highly personalized characteristics, it is gradually being applied to many fields such as national defense, aerospace, mechanical electronics, transportation and biomedicine. Digital light processing (DLP) technology mainly uses a projector to solidify photosensitive polymer liquid layer by layer to create a 3D printed object. Due to its ultraviolet light projection, it is quickly applied to the 3D printing field and has become another new rapid prototyping technology.

[0003] Compared with other 3D printing devices on the market, DLP devices can print products with higher detail accuracy requirements because their projection pixel blocks can be as small as 50μm, thus ensuring that their processing dimensional accuracy can reach 20-30μm. The feature of surface projection also makes it more efficient when processing cross-sections of the same area. The projection mechanism of the device is mostly integrated, making the layer curing molding functional module more compact, so the size of the device is smaller. Its molding characteristics are mainly reflected in the following points: (1) high curing rate (high light efficiency at 405nm); (2) low cost; (3) high resolution; (4) high reliability. This technology has many advantages in 3D printing: (1) high-speed spatial light modulator, with a display rate of up to 32kHz; (2) high light efficiency, with a micromirror reflectivity of more than 88%; (3) window transmittance greater than 97%; (4) supported wavelength range between 365nm and 2500nm; (4) the optical efficiency of the micromirror is not affected by temperature.

[0004] The current market demand for 3D printing is mainly reflected in high precision, high surface quality, product adaptability, processing efficiency, processing cost, etc. Due to the limitations of material molding principles, current industrial-level 3D printing equipment has shortcomings such as insufficient surface quality of molded parts and limited dimensional accuracy. Through the demand for DLP-3D printing technology, the market demand for higher surface quality of parts can be met. The corresponding requirements for the DLP market are: (1) high resolution; (2) performance for 405nm wavelength; (3) cost control. Summary of the invention

[0005] The purpose of the present invention is to provide a transparent photosensitive resin for DLP 3D printing and a preparation method thereof. The photosensitive resin has good stability, high printing model accuracy, and uses Irgacure-2959 as a photoinitiator, with high light source utilization rate. At the same time, the composition of the components in the photosensitive resin is regulated so that the photoinitiator has good compatibility with the system, and the UV curing time is shortened, reducing the energy consumption of the system.

[0006] The technical solution for achieving the purpose of the present invention is as follows:

[0007] The transparent photosensitive resin for DLP 3D printing includes the following components by weight percentage: 40% to 60% of tetrahydrofuran acrylate (CTFA), 20% to 30% of difunctional polyurethane acrylate, 19.5% to 29.5% of active diluent, 0.02% to 0.03% of light absorber, 0.2% to 0.3% of photoinitiator Irgacure-2959, 0.1% to 0.3% of defoamer, and 0.1% to 0.3% of leveling agent.

[0008] Preferably, the model of the difunctional polyurethane acrylate is difunctional polyurethane acrylate JAZO11.

[0009] Preferably, the reactive diluent is a reactive diluent conventionally used in transparent photosensitive resin for DLP 3D printing, selected from trimethylolpropane triacrylate (TMPTA) or 1,6-hexanediol diacrylate.

[0010] Preferably, the light absorber is a light absorber conventionally used in transparent photosensitive resin for DLP 3D printing, such as Sudan III and other colorants.

[0011] Preferably, the defoaming agent is a defoaming agent conventionally used in transparent photosensitive resin for DLP 3D printing, such as BYK-088, BYK-028, etc.

[0012] Preferably, the leveling agent is a leveling agent conventionally used in transparent photosensitive resin for DLP 3D printing, such as BYK-358N.

[0013] Preferably, the transparent photosensitive resin for DLP 3D printing comprises the following components by weight percentage: 50% tetramethylene acrylate, 25% difunctional polyurethane acrylate, 24.5% trimethylolpropane triacrylate, 0.02% Sudan III, 0.2% Irgacure-2959, 0.1% BYK-088, and 0.2% BYK-358N.

[0014] Furthermore, the present invention also provides a method for preparing the transparent photosensitive resin for DLP 3D printing, and the specific steps are as follows:

[0015] According to the formula ratio, tetrahydrofuran acrylate, difunctional polyurethane acrylate and active diluent are stirred and mixed evenly, and then the light absorber and leveling agent are added and stirred continuously. Subsequently, the photoinitiator Irgacure-2959 is added and stirred thoroughly. Finally, the defoaming agent is slowly added and stirred evenly to obtain the photosensitive resin for DLP 3D printing.

[0016] Preferably, the stirring speed is 400-700 rpm.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The transparent photosensitive resin for DLP 3D printing of the present invention uses the photoinitiator Irgacure-2959 as a photoinitiator, has a fast curing speed and high production efficiency, and only requires a small amount of initiator to efficiently initiate material polymerization;

[0019] (2) The mechanical properties of the transparent photosensitive resin for DLP 3D printing after curing of the present invention are improved;

[0020] (3) The transparent photosensitive resin for DLP 3D printing of the present invention has less volatile organic matter (VOC) and does not have the so-called "plastic smell" of traditional resins, and is environmentally friendly. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. The following embodiments are used to illustrate the present invention but do not limit the scope of the present invention.

[0022] Example 1

[0023] The transparent photosensitive resin for DLP 3D printing is composed of the following ingredients by weight: CTFA 60%, JAZO11 20%, TMPTA 19.5%, Sudan III 0.02%, Irgacure-2959 0.2%, BYK-088 0.1%, and BYK-358N 0.2%.

[0024] The preparation method of the transparent photosensitive resin for DLP 3D printing is as follows: according to the formula ratio, 60% CTFA, 20% JAZO11, and 19.5% TMPTA are mixed and stirred evenly at a stirring speed of 400-700rpm, and then the light absorber Sudan III and 0.2% leveling agent BYK-358N are added, stirred for 30 minutes, and then the photoinitiator Irgacure-2959 is added, and stirred for 25 minutes. Finally, 0.1% defoaming agent BYK-088 is slowly added, and stirred evenly while adding to obtain the photosensitive resin for DLP 3D printing.

[0025] Embodiment 2-3

[0026] The preparation method of the transparent photosensitive resin for DLP 3D printing is as shown in Example 1, and the specific components are shown in Table 1.

[0027] Comparative Examples 1-2

[0028] The preparation method of the photosensitive resin for DLP 3D printing is as shown in Example 1, and the specific components are shown in Table 2.

[0029] Comparative Example 3

[0030] The preparation method of the photosensitive resin for DLP 3D printing is as in Example 1, and CTFA is not added to the components. The specific components are shown in Table 2.

[0031] Comparative Example 4

[0032] The preparation method of the photosensitive resin for DLP 3D printing is as in Example 1, except that JAZO11 is not added to the components. The specific components are shown in Table 2.

[0033] Comparative Example 5

[0034] The preparation method of the photosensitive resin for DLP 3D printing is as in Example 1, wherein Irgacure-2959 is replaced with KIPEM, a commonly used photoinitiator on the market. The specific components are shown in Table 2.

[0035] Table 1: Specific components in Examples 1 to 3 (by weight percentage)

[0036]

[0037] Table 2: Specific components in Comparative Examples 1 to 5 (by weight percentage)

[0038]

[0039] Table 3: Performance of various photosensitive resins for DLP 3D printing

[0040]

[0041] The constituent materials of the embodiment and comparative example are made into DLP 3D printing photosensitive resin, and the corresponding material shape is printed out with a DLP 3D printer for easy testing. The tensile strength is based on ASTM D638, the hardness is based on ASTM D2240, and the curing time during printing is tested at the same time. The specific test results are shown in Table 3. By comparing Example 2 with Comparative Examples 3 and 4, it can be found that the monomer and oligomer work synergistically to jointly promote the performance of the system. If one of the components is missing, the performance of the resin will be reduced. By comparing Example 3 with Comparative Example 3, it can be seen that the use of Irgacure-2959 can make the resin cure and form better than the use of KIPEM. In addition, the use of Irgacure-2959 can significantly improve the efficiency of light source utilization, save energy consumption, and increase the printing rate.

Claims

1. Transparent photosensitive resin for DLP 3D printing, characterized in that: The composition includes the following components by weight percentage: 40% to 60% tetrahydrofuran acrylate, 20% to 30% difunctional polyurethane acrylate, 19.5% to 29.5% active diluent, 0.02% to 0.03% light absorber, 0.2% to 0.3% photoinitiator Irgacure-2959, 0.1% to 0.3% defoamer, and 0.1% to 0.3% leveling agent.

2. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The model of the difunctional polyurethane acrylate is difunctional polyurethane acrylate JAZO11.

3. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The active diluent is trimethylolpropane triacrylate or 1,6-hexanediol diacrylate.

4. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The light absorber is Sudan III.

5. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The defoamer is BYK-088 or BYK-028.

6. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The leveling agent is BYK-358N.

7. The transparent photosensitive resin for DLP 3D printing according to claim 1, characterized in that: The composition includes the following components by weight percentage: 50% tetramethylene acrylate, 25% difunctional polyurethane acrylate, 24.5% trimethylolpropane triacrylate, 0.02% Sudan III, 0.2% Irgacure-2959, 0.1% BYK-088 and 0.2% BYK-358N.

8. The method for preparing a transparent photosensitive resin for DLP 3D printing according to any one of claims 1 to 7, characterized in that: The specific steps are as follows: According to the formula ratio, tetrahydrofuran acrylate, difunctional polyurethane acrylate and active diluent are stirred and mixed evenly, and then the light absorber and leveling agent are added and stirred continuously. Subsequently, the photoinitiator Irgacure-2959 is added and stirred thoroughly. Finally, the defoaming agent is slowly added and stirred evenly to obtain the photosensitive resin for DLP 3D printing.

9. The preparation method according to claim 8, characterized in that: The stirring speed is 400~700rpm.

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