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Bioprinting Biocompatible Hydrogels from Cellulose Inks

Researchers from Italy and Sweden add to the ongoing trend for improving bioprinting techniques and materials. Upon developing bio-based photocurable materials for 3D printing and bioprinting with hydrogels, the authors released the details of their study in ‘DLP 3D Printing Meets Lignocellulosic Biopolymers: Carboxymethyl Cellulose Inks for 3D Biocompatible Hydrogels.’

Modified carboxymethyl cellulose was at the center of this experiment for bioprinting with digital light processing (DLP). While more commonly used as a filler, cellulose has been used in other inks. Beginning the research with the study of lignocellulosic biopolymers, the authors explained that they present a range of options for printing with DLP, while carboxymethyl cellulose (CMC) is often used in food, paint, and detergents. For this reason, it is a sustainable material with particular utility in bioprinting.

Approved by the FDA, and deemed biocompatible, CMC is water-soluble, versatile, and considered “an ideal candidate for the preparation of novel photocurable resins for DLP.” These types of formulations can also imitate cell microenvironments because of their similar makeup to glycosaminoglycan found within the extracellular matrix.

“Due to its versatility, its advantageous properties, water-solubility, and susceptibility to further functionalization, we also expected CMC would be an ideal candidate for the preparation of novel photocurable resins for DLP,” explained the authors. “However, the use of light-assisted printing techniques requires reactive photocrosslinkable functional groups, which means CMC needs functionalization to produce ink formulation for the production of 3D photocured hydrogels.”

“CMC was therefore methacrylated and its photorheology and DLP printability was investigated in two formulations, namely, M-CMC/Dulbecco’s Modified Eagle Medium (DMEM) and M-CMC/water, in presence of a fixed amount of lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) photoinitiator.”

(A) Scheme for the methacrylation of carboxymethyl cellulose (CMC). The presented product only presents one of the possible reaction products. (B) FTIR and (C) 1H NMR spectra for methacrylated CMC (M-CMC, red) and neat CMC (CMC, black).

During evaluation, the authors also investigated compatibility for hydrogels, with M-CMC solubilized in a culture medium (DMEM). Rheological properties (storage modulus, G′, and loss modulus, G″) were evaluated during UV curing for CMC/DMEM/LAP and M-CMC/water/LAP:

“Although the formulation M-CMC/DMEM/LAP showed a slight delay with respect to the onset of the curing process, the DMEM medium still allowed sufficient light penetration for the photocuring process in view of 3D printing,” said the researchers.

Both the CMC/DMEM/LAP and M-CMC/water/LAP formulations proved to be stable after 90 s of UV irradiation. Hydrogels were created from both formulations, and deemed “extremely promising” in comparison with other DLP biocompatible materials.

(A) Photorheology of methacrylated carboxymethyl cellulose (M-CMC) 20 mg/mL (2 wt% lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP)) solubilized in water (black) or in culture medium (pink). (B) Gel point. Film thickness 300 m. (C) Frequency sweep. Strain rate 1% and oscillation frequency from 0.01 to 10 Hz.

The researchers created a variety of 3D printed samples, to include cylinders, parallelepipeds, and other complex structures—all stemming from the M-CMC/DMEM/LAP and M-CMC/water/LAP formulations. On further evaluation, the hydrogels were stable, flexible, and the photocrosslink reaction was completed. Although dyes can be helpful in limiting light diffusion, there is also the risk of cytotoxicity, leading the authors to avoid such use in this study.

3D printed M-CMC hydrogels. (A) Simple cylinders and parallelepipeds (solvent: water). (B) The hydrogel exhibited good flexibility and handleability. (C) SEM analysis performed on the freeze-dried hydrogel. (D–F) 3D objects printed from water (D) and from culture medium solution (E,F).

Crosslinking and reactivity were further evaluated, along with compression tests, assessment of swelling ability, and cytotoxicity testing to investigate lack of cell death due to release of LAP photoinitiator or unreacted polymer chains. Ultimately, the team of researchers reported that there were no signs of cytotoxicity, and overall, their work was successful with cells exhibiting viability similar to control samples.

3D-printed M-CMC hydrogels. (A) Simple cylinders and parallelepipeds (solvent: water). (B) The hydrogel exhibited good flexibility and handleability. (C) SEM analysis performed on the freeze-dried hydrogel. (D–F) 3D objects printed from water (D) and from culture medium solution (E,F).

[Source / Images: ‘DLP 3D Printing Meets Lignocellulosic Biopolymers: Carboxymethyl Cellulose Inks for 3D Biocompatible Hydrogels’]

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Bioresorbable Ceramics Allow Admatec to Make 3D-Printed Bone Implants

Before I started writing about additive manufacturing a number of years ago, I thought ceramics were only used to make fancy pottery. While it is used for this purpose as well, the hard, non-metallic material is so much more than that: it’s strong in compression, can withstand very high temperatures and chemical erosion, and a SmarTech Analysis report suggests that the ceramics AM market will reach an estimated $4.8 billion in revenue by the year 2030.

Focused on advanced ceramics and metal 3D printing, Dutch company Admatec is now introducing bioresorbable ceramics to its portfolio. CAM Bioceramics, an ISO 13485:2016 certified supplier of medical grade ceramics, is supporting Admatec in its endeavor to introduce new 3D printing opportunities for the material via its Admaflex printers in the medical and dental fields.

“As a supplier for the Orthopaedic and Dental market, CAM Bioceramics acknowledges that 3D Printing will play an increasingly significant role in numerous patient treatment plans. Calcium Phosphate based bone reconstructions will play an important part in this next generation medical device solutions due to its proven biocompatibility,” said C. Hogeboom, CEO of CAM Bioceramics. “As one of the market leaders in this area, CAM Bioceramics actively partners with 3D print experts and promotes the evolution of 3D printed solutions.”

Advanced ceramic materials have a great deal of utility in medical applications, particularly when fabricating surgical instruments and implants. 3D-printed, patient-specific implants made from bioresorbable and biocompatible ceramics are often used in craniomaxillofacial and hemimaxillary surgeries, as they can be absorbed by the human body. Native bone tissue will eventually replace the implant, so it won’t need to be removed later along with autologous bone (harvested from the patient’s own body), which can be painful for patients.

While tricalcium phosphate, or bone ash, is often used in this application, bioactive hydroxyapatite—chemically similar to the mineral component of bones—gives the body more time to heal, as it takes longer for the body to absorb it. By working with CAM Bioceramics, Admatec can now use a commercially available hydroxyapatite slurry material in its Admaflex DLP 3D printers to make patient-specific implants.

Implants that are bioresorbable can be made with very defined pore structures and geometries. Additionally, 3D printing these means that it’s possible to define an optimal geometry for the implant, so it perfectly fits the patient. Bone ingrowth from nearby tissues in the body is facilitated by using both dense and porous structures in bone tissue engineering, and 3D printing fits the bill, as it can produce interconnected scaffolds with well-defined sizes and geometries.

“Using Hydroxyapatite, we can manufacture patient-specific, bioresorbable implants, which have defined pore structures and geometries,” Admatec stated in a press release. “Combinations of functional graded ceramic materials, such as dense and porous structures in a single hemi-maxillary bone-like structure, have been printed successfully with help of the lithography based additive manufacturing technology provided by Admatec.”

Admatec’s suggests that its technology can efficiently print complex channels, geometries, and lattice and honeycomb structures with wall thicknesses and features in the 100 μm range. Its batch-oriented process can print larger implants and its multi-part printing software can help print different geometries simultaneously for smaller implants.

“Engineering know-how, flexibility and ease of use of the Admatec system have convinced CAM Bioceramics to collaborate with Admatec in this development thus enabling other medical device companies to take full advantage of this ‘turnkey’ solution,” said Giuseppe Cama, Head of Innovation & Science at CAM Bioceramics. “Customization to optimize patient outcomes can easily be achieved, supported by the physical proximity of the two companies.”

With its newly available bioresorbable ceramics, Admatec can offer medical device manufacturers even more customized solutions. For instance, the company is now working on multimaterial DLP 3D printing, where a combination of zirconia and hydroxyapatite is used to print combination implants for the lower jaw.

Large bone defects resulting from tumors or severe trauma can’t heal on their own without assistance, and one potential solution is a cage, 3D printed out of high-strength zirconia or another ceramic material, that can support the area while it’s healing. The cage would be paired with an implant, featuring an inner volume of bioresorbable ceramic, like hydroxyapatite, and because they’re biocompatible, both could be left in the body.

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(Source/Images: Admatec)

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University of Auckland: Growth-Induced Bending of 3D Printed Samples Based on PET-RAFT Polymerization

4D printed objects are 3D printed objects made with smart materials that respond to environmental stimuli, like liquid and heat, or return to an original form after deformation. Researchers from the University of Auckland published a paper regarding 3D printing and growth-induced bending based on photo electron/energy transfer reversible addition-fragmentation chain-transfer (PET-RAFT) polymerization.

By adding reversible deactivation radical polymerization (RDRP) constituents to a 3D printed structure to create “living” materials, which keep polymerizing on-demand, allows structures to be built with post-production functionality and modularity. But, as the Auckland team states, “this forms only half of the solution.”

RAFT processes have been used as a controlled polymerization technique to help with self-assembling macromolecules and block copolymerization. They previously demonstrated photo-RAFT polymerization 3D printing under several visible wavelengths, showing that a facile surface modification “could be performed on the samples after printing with a range of different monomers.”

Graphical abstract

“For this work, we further optimized the PET-RAFT 3D printing formulation and demonstrated the 3D printability using a commercial DLP 3D printer with standard 405nm light sources,” they wrote. “We also explore the 4D post-production modification capabilities of the 3D printed object using green light (λmax = 532 nm).”

The PET-RAFT recipe they used, below, adds a tertiary amine and the photo redox catalyst EY, the latter of which “is raised to an excited state (EY*) under irradiation where it then has several pathways to release its energy.” This is useful for 3D printing, since it’s a desirable “oxygen tolerant pathway.”

(A) Chemical structures of Eosin Y (EY), 2-(butylthiocarbonothioylthio) propanoic acid (BTPA), poly (ethylene glycol) diacrylate (PEGDA, average Mn = 250 g/mol), N, N-dimethylacrylamide (DMAm), and triethanolamine (TEtOHA). (B) Proposed combined PET-RAFT mechanism showing tertiary amine pathway by Qiao, Boyer, and Nomeir15, 23-25 (C) Reaction scheme for PET-RAFT polymerization of our 3D printing resin. (D) Schematic of a standard DLP 3D printer.

In their previous research, they used a 3D printing resin that was much slower to polymerize, and produced brittle objects. This time, they made several changes to the resin, such as replacing the RAFT agent CDTPA with BTPA and adjusting monomer composition.

“The development of an optimized 3D printing resin formula for use in a commercial DLP printer (λmax = 405nm, 101.86µW/cm2) was the first step in this research. Thus, several criteria were used to determine the quality of the optimized resin; the optimized resin must be able to hold its form in 60 seconds or less exposure time, the printed objects must have a good layer to layer resolution and binding, must be an accurate representation of the CAD model, and the resin must be stable enough to be reusable for consecutive runs,” the team explained.

They kept these criteria in mind while creating and testing new resin recipes with Photo Differential Scanning Calorimetry (Photo-DSC) and a 400-500 nm light source range.

“A monomer to RAFT agent ratio of 500:1 was chosen as a balance between a faster build speed, and a high enough RAFT concentration to perform post-production modifications,” they said. “For the first step in optimization we decided to compare two asymmetric RAFT agents, CDTPA and BTPA.”

Photo-DSC plot showing resin composition of [BTPA]: [PEGDA]: [EY]: [TEtOHA] = 1:500:0.01:20 (blue), [BTPA]: [PEGDA]: [DMAm]: [EY]: [TEtOHA] = 1:350:150:0.01:20 (green), [BTPA]: [PEGDA]: [DMAm]: [EY]: [TEtOHA] = 1:150:350:0.01:20 (red), [CDTPA]: [PEGDA]: [EY]: [TEOHA] = 1:500:0.01:20 (black), and [CDTPA]:[PEGDA]:[EY]:[TEA] = 1:200:0.01:2 (orange) form our previous PET-RAFT work, were compared to find an optimum new resin formula. The effects of different RAFT agent and comonomer ratio are noticeable on the maximum heat flow and the peak position of tmax.

The first formula, [BTPA]: [PEGDA]: [EY]: [TEtOHA] = 1:500:0.01:20, had a limited inhibition period, while [CDTPA]: [PEGDA]: [EY]: [TEtOHA] = 1:500:0.01:20 had a longer one.

“These results help to demonstrate the increase in polymerization rate that can be achieved by using BTPA in place of CDTPA,” they noted.

Because of its high glass transition temperature, DMAm was added as a comonomer in [PEGDA]: [DMAm] = 70:30 and 30:70 ratios. This slowed the polymerization rate for the resin formulas [BTPA]: [PEGDA]: [DMAm]: [EY]: [TEtOHA] = 1:350:150:0.01:20 and [BTPA]: [PEGDA]: [DMAm]: [EY]: [TEtOHA] = 1:150:350:0.01:20, but it was still faster than the CDTPA formulation. The researchers used this formulation to 3D print samples for dynamic mechanical analysis (DMA) and 4D post-production modification.

UV-Vis absorption spectra; (A) EB under 405nm (397.45µW/cm2) exposure for; initial (black), 10 (red), 20 (blue), 30 (magenta) and 40 minutes (olive). (B) EY under 405nm exposure for; initial, 10, 20, 30 and 40 minutes.

It’s important that photocatalysts don’t have issues like photobleaching or photodegradation during a photocatalytic process. Above, you can see a comparison in absorbance loss between organic photocatalysts EY and Erythrosin B (EB), “using their absorbance curves after different periods of 405 nm light irradiation.”

“Both showed a noticeable gradual decrease in UV absorbance which could likely be due to irreversible photodegradation, given that the effect remains after the sample has been stored overnight in a dark environment and measured again,” the team explained.

After longer periods of time, the EB solution started changing color, but this didn’t happen with the EY formulation, which is why the team kept it in their 3D-RAFT resin composition. A photostable catalyst, like EY, makes it possible for the 3D printing process to continue undisturbed.

The 3D printed samples that underwent DMA analysis were:

optimized RAFT resin before and after post-production modification
non-3D printed DMA sample by PET-RAFT polymerization in bulk
3D printed free radical polymerization (FRP) control sample

The first type were 3D printed with a 30 µm thickness, a 60 second attachment time, and 30 seconds of exposure per each of the 53 layers. The second was fabricated with the same optimized formula “but polymerized in bulk using an external mold and a conventional 405nm lamp external,” while the FRP samples were printed with the same monomer composition and parameters but used a “conventional photoinitiator, phenylbis (2, 4, 6-trimethylbenzoyl) phosphine oxide (TPO).”

DMA plot showing (black) storage modulus (E’) and (black dashed) Tan δ from 3D printed DMA sample by normal FRP of resin formula [PEGDA]: [DMAm]: [TPO] = 350:150 and 2wt% TPO; (blue) the E’ and (blue dashed) Tan δ from 3D-RAFT printed DMA sample using resin formula [BTPA] :[PEGDA]: [DMAm]: [EY]: [TEtOHA] = 1:350:150:0.01:20; (green) the E’ and (green dashed) Tan δ from the post-print modified DMA sample; lastly (red) the E’ and (red dashed) Tan δ from the non-3D printed DMA sample prepared by normal PET-RAFT polymerization in bulk.

A temperature ramp (2˚C/min) was performed in order to find the storage modulus (E’) and glass transition temperature (Tg) of the samples, and there was a major change “in the E’ to 80 MPa and Tg to 15˚C” when the samples were compared to ones that weren’t 3D printed but instead polymerized in a mold.

“This layer-by-layer construction appeared to play a major role in the E’ at room temperature of the overall sample,” the team noted. “Each layer in the 3D printed sample received equal light irradiation (apart from attachment layer where specified), whereas in the bulk samples light had to penetrate through the entire thickness of the resin.”

Samples printed with RAFT resin had methyl methacrylate (MMA) monomer inserted post-production “in a growth medium devoid of solvent,” and DMA was used to analyze the effect of this modification on the prints’ mechanical properties, as well as “the relative effect on E’ and Tg of the sample.”

“The E’ at room temperature of the sample had decreased to 100 MPa but the Tg remained constant at about 19˚C,” they explained. “These limited changes can largely be attributed to the fact that BTPA is an asymmetric RAFT agent, all the growth being surface focused thus limiting the mechanical effects on the 3D printed RAFT sample.”

A1) CAD model for shapes upon 3 × 3 cm base. A2) Corresponding 3D-RAFT objects printed using DLP 3D printer. B1) Kiwi bird CAD model upon tiered base. B2) Corresponding 3D-RAFT printed object.

Once they determined the optimal RAFT 3D printing resin, the researchers designed CAD models for the objects they would print. They arranged different shapes, like triangles and Kiwi birds, on top of square and hexagonal base plates and circular coins, in order to see how the PET-RAFT resin formulation could handle features like corners and curves.

“These objects generally represented an accurate 3D print of the corresponding CAD model, confirming that the current 3D-RAFT resin was capable of printing 3D objects using a 405nm DLP 3D printer (λmax = 405 nm, 101.86µW/cm2),” they noted.

“Objects printed with 3D-RAFT also displayed an actual build speed of 2286 µm/hr (calculated from the actual height of printed objects over the full print time) consistent with that of the theoretical build speed, which is significantly faster than our previous PET-RAFT resin formula…”

Only limited shrinkage occurred on these prints, and after being washed for two days each in ethanol, THF, and DMSO, the team did not note a visible loss in yellow “arising from the trithiocarbonate group of the RAFT agent.” The 3D-RAFT resin was also reusable over more than ten prints.

“Having demonstrated that we could reliably print objects using our new RAFT resin, we endeavoured to demonstrate that these objects had retained their desired “living” behavior and could undergo post-production modification,” the team wrote.

They immersed half of a 3D-RAFT printed strip in a growth medium containing [BA]: [EY]: [TEtOHA] = 500:0.01:20 in DMSO. Then, a green 532 nm LED light was directed onto one of its faces, and after 15 minutes, “the strip showed moderate curvature.” They could see the strip was bending considerably after 15 more minutes, and it was also much softer, with the irradiated face paler than the other, and the growth medium was cloudier.

Optical images and graphical representations of growth-induced bending process. (A) The initial 3D-RAFT printed strip. (B) 3D-RAFT strip after 15 minutes monodirectional green light irradiation (532nm, 58.72µW/cm2) in a growth medium of DMSO and BA. (C) The same strip after 30 minutes monodirectional green light irradiation in the same growth medium. (D) Reaction scheme for the photo-catalyzed insertion of BA monomer under green light irradiation.

They next performed some control experiments. First, they tried the same thing with an FRP printed strip and a [PEGDA]: [DMAm] = 350:150 and 2wt% TPO growth medium, but this did not bend. A 3D-RAFT printed strip was left to soak in the original growth medium, without any light irradiation, for 24 hours, “to ensure that the bending was coming from growth rather than an alternate stimulus such as solvent swelling,” and saw no changes. Finally, they tried the same original process to return the bent 3D-RAFT strip back to its original form by shining the green light at it from the opposite direction. While it ultimately worked, it took three hours of irradiation to bend the strip back, which “indicates the unfavorability of introducing stress on the opposing side of the strip by our current methods.”

“To the best of our knowledge, this is the first demonstration of the growth of new material into the surface of an existing 3D printed object using RAFT polymerization to induce a bending response,” they concluded.

“In summary, we have further developed a 3D printable RAFT resin formula with an improved build speed up to 2286 µm/hr and demonstrated its ability to undergo 4D post-production transformation. We first demonstrated a facile method for growth induced bending of 3D-RAFT printed strips which opens an alternative pathway for movement and modification of these printed objects.”

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Single & Multimode Silica Optical Fibers Drawn from 3D Printed Preforms

In the recently published, ‘Silica optical fiber drawn from 3D printed preforms,’ the authors created single and multimode fibers that can be used to create designs and parts for a range of networks, likely related to telecommunications and Internet of Things (IoT) technology.

Silica optical fibers are ‘the holy grail of 3D printing optical fiber,’ according to the authors, due to a ubiquitous nature and levels of low loss; in fact, the researchers state that there is not another alternative able to compete. For this study, the researchers investigate the process of creating a silica preform through both 3D printing and thermal processing—no small feat, considering it requires temperatures over T = 1900 ℃. To avoid this issue, the researchers tried using a lower melting polymer—a hybrid polymer-glass mix—via DLP printing. Steps involved in this process include:

Photocurable resin preparation
3D printing of preforms
Core fabrication
Thermal debinding
Final fiber drawing

Fabrication of the step-index silica optical fiber using 3D printing.

The researchers polymerized the mixed resin with the DLP printer and went on to fabricate arbitrary structures. They designed the preform with Inventor CAD, and then it was 3D printed, cured with UV light. After debinding, the researchers placed the preform into a quartz tube for support, with a lower drawing temperature to eliminate water, air, and residual polymers.

“As the temperature gradually increased, the polymer is ablated leaving behind the silica nanoparticles, which come closer together leading to preform shrinkage,” state the researchers. “Sintering at higher temperatures fuses them together.”

Refractive index difference profile

The quality of the fiber was examined with an optical microscope, demonstrating the cross-section of both 3D printed single and multi-mode.

a) experimental configuration of loss measurement b) loss spectrum of the 3D printed multimode.

Fibers, with both minimum and maximum eclipse diameters, showed more elevated uniform tension. With ‘increased loss’ the potential for interfacial scattering is suggested, with ‘significant contribution’ from water—meaning that the bubbles may be holding trapped water. The researchers theorize that this could be resolved with the use of:

Higher purity, drier starting chemicals
Sintering and debinding
Removal of the outer silica tube

“In conclusion, whilst there remains considerable scope to improve the transmission properties of this fiber, the first single mode and multimode silica optical fibers have been drawn from a 3D printed preform. The relative ease in which this was achieved suggests additive manufacturing will disrupt optical fiber fabrication,” concluded the researchers.

“Unlike conventional labor-intensive, lathe-based methods, the design and fabrication are not limited by a centrally spun or finely stacked preform, enabling configurations such as improved multicore and complex optical fibers, such as optimized Fresnel fibers, to be made. More broadly, painstakingly difficult complex patterns, multicore and multi-size and shaped fibers can be made that are not otherwise possible. This work, building off the original polymer versions, marks a new and exciting time for fiber fabrication and application.

3D printing is a technology very centered around materials usage, from silicate bone scaffolds to printing with silicone and epoxies, composites, and more. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

[Source / Images: ‘Silica optical fibre drawn from 3D printed preforms’]

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4D Printed Shape Memory Polymers Given Better Performance & Recyclability

Authors Ang Li, Adithya Challapalli, and Guoqiang Li explore a trend that continues to grow: 4D printing. Their findings are explained in the recently published “4D Printing of Recyclable Lightweight Architectures Using High Recovery Stress Shape Memory Polymer.” Here, the benefits of smart materials that can adapt to their environment are explored as the researchers consider challenges in 3D printing self-healing shape memory polymer (SMP) microlattices, and move forward to develop their own thermoset polymer offering the following features:

High strength
High recovery stress
Perfect shape recovery
Good recyclability
3D printability with DLP

The ability to create lightweight structures is one of the greatest benefits of 3D printing, but users are continually looking for better ways to have it all, including good mechanical properties. This is especially important in advanced engineering applications where capabilities such as the following are in demand:

Shape memory
Recovery stress
Damage healing
Recyclability

Schematic of recyclable and shape memory microlattices using 3D-RSMP. (a) 3D printing (direct light printing (DLP) of advanced multifunctional microlattice structures using the 3D-RSMP. (b) Compression programming of the printed microlattice to a temporary shape and recovery to the original shape. (c) Recycling of the ball milled multifunctional microlattices under high pressure and high temperature. (d) The remolded specimen for mechanical tests.

3D printed shape memory polymers tend to offer better potential, offering higher speed in production, less energy consumption to produce, and less post-processing. Shape memory effect is usually improved too, in what is ultimately the process of 4D printing, bringing forth ‘stimuli-responsive self-evolving features’ which offer better performance for load-bearing parts and structures. Before this study, however, the researchers found a resource for SMPs with high stress output lacking. Creating a higher-performance SMP meant turning to thermosets and either DLP or SLA methods.

The research team created a specialized 3D-RSMP resin for universal DLP 3D printing, offering mechanical properties they believe to be as good as some of the ‘best commercial DLP resins without multifunctionality,’ with higher shape memory and better self-healing qualities. 3D structures were designed in SolidWorks and then 3D printed on the Asiga Pico 2, with 3D-RSMP resin with 0.15mm layer thickness. Samples were also tested for recycling, crushed and broken, and then ground up via ball milling. Afterward, the researchers added the particles to a steel mold, with pressure applied at 200 °C or 150 °C for 2 hours.

Recycling of the crushed microlattices. (a) A recycling process is described: broken and failed shape memory microlattices were crushed into powders via ball milling; a steel mold was used for recycling milled powders of 3D printed microlattice structures under varying conditions. A mechanical test was performed on the remolded rectangular specimen made of the milled powders. (b) Typical tensile stress vs. strain curves of the remolded rectangular specimens obtained under varying conditions ((200C12M2H represents molding at 200 °C and under 12MPa pressure for 2h; 150C12M2H represents molding at 150 °C and under 12MPa pressure for 2h; and 150C9M2H represents molding at 150 °C and under 9MPa pressure for 2h) with a loading rate=0.5mm/min at room temperature.

The 3D-RSMP product appears so far to be the only SMP that can be both 3D printed and recycled—with recovery stress larger than 10MPa. In terms of application, the researchers also found their cubic microlattice to have the highest mechanical strength ‘with comparable or even higher specific compressive strength than metallic microlattices and ceramic microlattices without shape memory effect.’

“The results show that the cubic microlattice has mechanical strength comparable to or even greater than that of metallic microlattices, good SME, decent recovery stress, and recyclability, making it the first multifunctional lightweight architecture (MLA) for potential multifunctional lightweight load carrying structural applications,” concluded the researchers.

“Future work will be focusing on improving the recycling efficiency of the 3D-RSMP and the microlattice, and further optimizing the geometry through topological optimization or biomimicry in order to obtain microlattices with higher mechanical strength and shape memory effect for advanced structural and engineering applications.”

Mechanical properties of various microlattices upon compression. (a) Compressive strength vs. apparent density plots of various microlattices and foams. (b) Compressive modulus vs. apparent density plots of the three microlattices in this study.

While 3D printing is a source of fascination around the world, still, 4D printing takes fabrication to another magical level as researchers produce innovations like tunable metamaterials, multi-metals, and processes for other industrial applications.

Tree unit cell geometries have been drawn in Solidworks and then assembled to the corresponding microlattice structures. (Row 1: unit cells, from left to right: Octet unit cell (OCT UC); Kelvin unit cell (KVNUC); Cubic unit cell (CBC UC), Row 2: 3D printed microlattice structures, from left to right: Octet microlattice structure (OCT LTC), Kelvin microlattice structure (KVN LTC), and cubic microlattice structure (CBC LTC); Row 3: multi-length scale microlattices, from left to right: 1st order octet truss (1O OCT) and 2nd order octet truss (2O OCT)). (Te scale bar applies to all the five lattice structures).

[Source / Images: ‘4D Printing of Recyclable Lightweight Architectures Using High Recovery Stress Shape Memory Polymer’]

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With a Focus on DLP: Researchers 3D Printing High Resolution Tricalcium Phosphate Scaffolds for Bone Regeneration

In ‘Application of high resolution DLP stereolithography for fabrication of tricalcium phosphate scaffolds for bone regeneration,’ researchers examine how to make complex, stable scaffolds based on β-tricalcium. Typically, there are obstacles to finding materials and techniques suitable for creating structures capable of sustaining cell life.

Here, the authors are aware of the necessities in tissue engineering: the material cannot be toxic, obviously, as that would cause further health issues in a patient, biodegradability is key, with the material being absorbed along with suitable bone growth, and porosity and density must be suitable too, balanced out with proper strength.

(a): CAD of an assembly of 8 unit cells for the Grid structures and 1 unit cell for the Kagome structures; not to scale. (b): CAD of 6 mm cubes of the four scaffold types. (c): µ-CT slices in the x, y-plane of the scaffolds after filtering.

DLP 3D printing has proven successful for creating scaffolds due to comprehensive irradiation over the whole cross-section, and shorter processing times in comparison to other processes. The researchers focused on DLP 3D printing for this study, in relation to the use of calcium phosphate structures that are not only complex and high resolution but also strong. The team assessed both rectilinear grid structure and hexagonal geometries (at 50 and 75 percent porosity) for mechanical properties, with complete chemical analyses performed before and after bioprinting.

“Preosteoblast MC3T3 cells were used to evaluate biocompatibility of 3D printed scaffolds by DLP process and their ability to form bone in short term culture,” explained the authors.

In scaffold design, both the rectilinear grid structure and a hexagonal Kagome structure were created at two different levels of porosity, along with one non-porous specimen. All the designs were treated with scaling factors also, to compensate for shrinkage (1.267 in x, y directions and of 1.281 in z-direction).

The rectilinear grid structures were able to handle over twice the capacity of the Kagome scaffolds, which the authors attributed to ‘inhomogeneous stress distributions in the latter architectures.’ They also noted discontinuities in the Kagome structures, likely caused by cells failing under loading. The researchers also noted elevated activity in porous scaffolds on day one after seeding—perhaps due to ‘inhomogeneous seeding resulting in inconsistent areas of confluency and thereby in a broader range of onset time of differentiation.’ Increased ALP activity could be caused by osteogenic differentiation, however.

Representative stress-strain curves of scaffolds and of the nonporous F0 structure in compression. Distinct pop-in events marked with *.

“The DLP process does not negatively impact the attained results and it, as well as the utilized material, can therefore be considered as biocompatible,” concluded the researchers. “Thus, the presently manufactured β-TCP structures are promising for applications in bone regeneration as scaffolds and could also be employed as a starting point for composite structures. For instance, in approaches where a ceramic framework is coated or impregnated with a polymer, a solid and reproducible scaffold foundation, such as described in the present paper is vital.”

Bone regeneration is one of the hottest topics lately, mainly because it is an area of great challenge for researchers and medical professionals, who are continually trying to improve quality of life for patients around the world, through researching new materials meant for bioprinting, fabricating new scaffolding, and even bioprinting in situ. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

Cell number from DNA quantification of the different 3D scaffolds in osteogenic medium; n = 3, with SD, n.s. for no statistically significant difference, * for P ≤ 0.005, and ** for P < 0.001.

[Source / Images: Application of high resolution DLP stereolithography for fabrication of tricalcium phosphate scaffolds for bone regeneration]

3D Printing News Briefs: May 26, 2019

This year’s RAPID + TCT ended late last week at the Cobo Center in Detroit, so we’re again starting off today’s 3D Printing News Briefs with more news from the busy show floor. DyeMansion launched a new extended color series at RAPID, while 3D Systems made the announcement that its Figure 4 Modular is now available. Moving on, SLM Solutions just celebrated the grand opening of its new Shanghai application center. Finally, a Reddit user made an adorable miniature 3D printer.

RAPID 2019: DyeMansion’s New Colors

DyeMansion at RAPID 2019 [Image: Sarah Saunders]

Munich startup DyeMansion, a leader in finishing and coloring solutions for 3D printing, launched its new ColorsX extended color series for end-use products at RAPID last week, in order to continue helping its customers achieve the perfect finish for all of their applications. Automotive ColorsX and Neon ColorsX are the first solutions under the startup’s X Colors for X Industries premise, with more to follow in the future. The automotive color line has improved light and heat resistance for better 3D printed polyamide components and interior car parts, and features Automotive BlackX, which has a less saturated black tone than DyeMansion’s basic DM Black 01 and was created according to ISO EN 105 B06 method 3’s hot irradiation standards. The luminous neon color line includes GreenX, YellowX, OrangeX and PinkX to help create striking end-use products. Both of these new color lines are compatible with DyeMansion’s PolyShot Surfacing (PSS) and VaporFuse Surfacing (VFS).

“Some of our earliest customers who made use of DyeMansion Print-to-Product technologies for serial production are from the Automotive and Lifestyle industries,” explained Kai Witter, DyeMansion’s Chief Customer Officer. “While working closely with our customers, joint strategies are always about creating even more value to their businesses. So, I feel very delighted to now offer additional value creating products. Automotive and Neon ColorsX are only the beginning of providing more specific industry offers.”

Once DyeMansion decided to launch its ColorsX series, it also named the coloring process it established back in 2015: DeepDye Coloring (DDC), which can be easily controlled and traced through integrated RFID technology and offers a limitless choice of custom colors.

RAPID 2019: 3D Systems Announces General Availability of Figure 4 Modular

Also at RAPID last week, 3D Systems announced the general availability of its scalable Figure 4 Modular production platform. The flexible digital light printing (DLP) system has multiple configurations that can print parts with high surface quality, and allows manufacturers to iterate designs more quickly, as well as produce end-use parts without having to worry about a minimum order quantity. Three models make up the Figure 4 – Standalone, Production, and Modular – and several customers, such as D&K Engineering and Midwest Prototyping, are reaping the benefits. Additionally, 3D Systems also announced five new DLP and SLS materials, the first of which is the immediately available Figure 4 FLEX-BLK 10. The other new Figure 4 materials, such as TOUGH-BLK 20, MED-AMB 10, MED-WHT 10, and HI-TEMP-AMB 250, are expected to be available in Q3 and Q4 of 2019.

“The newest additions to our plastic 3D printing portfolio demonstrate our commitment to driving the adoption of digital manufacturing. With the industry’s first, truly scalable plastic production platform and our robust selection of materials, 3D Systems enables customers to rethink manufacturing and realize improved agility, reduced complexity, and lower overall total cost of operation,” said Vyomesh Joshi, the President and CEO of 3D Systems.

3D Systems also announced that its customers Rodin Cars (based in New Zealand) and North Carolina-based Stewart-Haas Racing are using its plastic and metal 3D printing solutions to improve the speed and performance of their cars.

SLM Solutions Celebrates Opening of New Shanghai Application Center

The same year that SLM Solutions opened an applications and demonstration center in Germany, it also established Chinese operations in Shanghai. Earlier this week, the selective laser melting experts celebrated the grand opening of their expanded office facilities and application center in Shanghai, which will help the company continue to grow its presence on the Asian market. The new center has installed four SLM systems: one SLM 125, one SLM 500, and two SLM 280 printers. Additionally, the facility also has equipment to represent an SLM build’s supporting process chain, such as a metallurgical lab and post-processing capabilities. The grand opening included a tour through the new new customer service and application engineering center.

“As we continue to grow our Chinese team, the opening of our Shanghai Application Center is an important milestone in SLM Solutions’ development and indicates the confidence in the Chinese market,” stated Jerry Ma, General Manager of SLM Solutions (Shanghai) Co., Ltd. “As part of the global strategy for growth we have the capacity to more than double our number of employees and the equipment to support all Chinese users with the technological resources shared by our applications centers around the world. We can also provide high-quality, fast technical services to better promote the development of selective laser melting and create more value for customers.”

Mini 3D Printed 3D Printer

A reddit and imgur user by the name of “Mega Andy” used 3D printed parts and DVD drive motors to make his own miniature 3D printer. And by miniature, I mean that he used a banana for scale, which was taller than the 3D printed 3D printer itself! It’s a really interesting project – the device runs Marlin, and features a glass bed and an E3D V6 hotend. The black and gold parts of the mini 3D printer were made out of PLA material, while PETG was used to make teeth for the leadscrews. Speaking of this, Mega Andy said that the printer is “fairly unreliable” because it easily ruins the teeth that guide the device on the leadscrew. Additionally, he’s also working to improve and lengthen the Z axis due to binding problems. Mega Andy released the STLs onto Thingiverse so others could try to make their own versions of the miniature 3D printed 3D printer…say that five times fast.

“So this project is nothing new, people have made 3d printers, CNC, engravers before using this hardware. What I wanted to do differently with this is have a designed 3D printed frame to hopefully fit standard parts. Instead of mounting full metal dvd drive assembly’s together and look like a DIY project I wanted a something that could be more compact and neat,” Mega Andy wrote on Thingiverse.

“This project is not for everyone and would only recommend to someone with a decent knowledge of 3d printers, basic soldering and lots of patience. Also some fiddling was needed to get the right amount of tension on the leadscrew, this bit is a massive pain but hopefully no one else needs to go through quite as much issues as i did with this bit. They will wear out though and a 3d printer will be needed to print new parts for it when they inevitable wear out.”

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3D & 4D DLP Printing with Functionally Graded Materials

In ‘Grayscale digital light processing 3D printing for highly functionally graded materials,’ Chinese researchers make it clear that 3D printing has a long way to go for producing excellence in parts without significant investment and engineering. In looking toward biological structures, the authors suggest that functionally graded materials (FGMs) can improve mechanical properties of 3D printed objects. In assessing previous studies, they also settled on DLP 3D printing as the most promising method—especially for creating multi-material parts.

In this study, the researchers explain how they created a new 3D printing ink, used in grayscale printing with the single-vat grayscale DLP (g-DLP). The ink is meant to serve as the material for fabrication of highly tunable property gradients. Cured with grayscale light patterns that form the 3D printed structure, the object is cured a second time to ‘eliminate most of the residual monomers’ and improve mechanical properties. Ultimately, the researchers discovered that ‘broadly tailored functional gradients’ could be made, as they created lattice structures and different metamaterials.

g-DLP 3D printing of FGM via two-stage curing. (A) Schematics showing the g-DLP printing of graded material via a two-stage curing process. A hybrid ink was used for
DLP 3D printing first followed by thermal curing the printed part in a heating oven. (B) Predicted normalized conversion of cured material under different grayscale light with only
one exposure (solid lines) and multiexposure (dashed lines) by the model using the exposure time of 20 s and curing thickness of 60 mm per layer. (C) Gel fraction of hybrid ink after
the first- and second-stage curing. (D) Tensile stress-strain curves of printed materials using different grayscale during printing (sample size, >3). (E) Young’s modulus and glass
transition temperature of printed materials as functions of grayscale. (F and G) Design, print part under bending, and corresponding FEM simulation of graded materials enabled
by g-DLP using a discrete gradient (F) and a continuous gradient (G) grayscale pattern. Scale bars, 5 mm.

A hybrid ink was created, and the researchers used a two-stage curing mechanism to refine the parts, with GMA monomers and diamine cross-linkers responsible for the thermal curing process. They examined the impact of grayscale on photopolymerization of the ink. Looking back at previous processes, the research team realized that two-stage curing systems usually produced uniform polymer networks or phase-separation structures. With their new method, the network was creating with both tunable density and chain architecture—without toxins, meaning that it is safe for many different applications.

“The differences in the network architecture and cross-linking density of the materials lead to widely tunable mechanical and thermomechanical properties. We first evaluated the mechanical properties of the printed materials,” stated the researchers. “The samples were printed using a single grayscale light for the first-stage curing. With only the first stage photocuring, the Young’s modulus spans only a few times from 1.5 to 8.1 MPa when the grayscale varies from G80 to G0, which is not enough for broader applications.

Continuing to show the potential of g-DLP printing, the researchers also printed simple geometrical shapes with gradients, along with further exploring 3D printing lattices and bioprinted structures which displayed high resolution and ‘clean appearance.’ They also found that these printed structures deformed suitably for applications like energy absorption, bordering on the 4D realm as shape memory polymers, envisioning use in future applications like:

Voxel printing
4D printing for metamaterials
Presurgical model planning
Soft robotics
Additive manufacturing with cyber security

“Although our approach enables significant advantages, there are still several issues that need to be addressed for its wide applications. First, the actual resolution of properties for the g-DLP should be determined. Besides the printer device itself, the voxel resolution for g-DLP in the x-y plane and z axis can be affected by both the resin and the printing parameters. Moreover, the grayscale value of the pixel would also have an influence on the voxel resolution. Second, the relationship between the curing condition, molecular structures, and mechanical properties of the grayscale cured samples needs to be further understood,” concluded the authors. “The nanoscale mechanical test and modeling approaches would provide an attractive pathway to this end, which is part of the ongoing work.”

“Last, when grayscale is used, polymers are cured to different degrees, which results in a slight difference in printed size. However, this can be fixed by software. For example, the projecting area with larger grayscale can be adjusted larger to compensate for the difference.”

Applications of g-DLP–printed composites for sequential SMP components and 4D printing. (A) Design and print part of a helical SMP component with increasing
grayscale level on the hinge from G20 to G80. (B) Snapshot showing the sequential shape recovery process of the helical SMP component with graded hinge materials in hot water
(~60°C). (C) Design and print part of a sequential SMP as an artificial arm. (D and E) Snapshot showing sequential shape recovery of a single artificial arm (D) and artificial arms for
soft robotics to lift a stick (E) by a heat gun. (F) Schematic of a shape-shifting film by cold drawing of printed lamina fiber-reinforced composites with asymmetric fiber distribution
and recovery process. (G) Pictures of the printed strip with 0° of fiber orientation: original shape and bending shapes by applied stretching strain at room temperature. Scale bars,
1 cm. Photo credit: Xiao Kuang, Georgia Tech

Improving mechanical properties in 3D printing is a challenge that many users have taken on lately as they hope to make stronger, more functional parts whether in scaling up nanotechnology, formulating inks and resins, or studying how other factors affect strength and durability. Find out more about how mechanical properties affect 3D printed parts and how they can be improved here. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

Graded metamaterial via g-DLP for multifunctional applications. (A and B) Design, print part, experimental compression test, and FEM of a 2D lattice and cellular
metamaterial for controlled buckling (A) and pattern transformation (B), respectively. (C) Design and print part of a 3D lattice metamaterial. (Dand E) Synchronous deformation (D)
and sequential deformation (E) of the 3D lattice in the x and z axes, respectively. (F) Compression stress-strain curves of the anisotropic 3D lattice in the x and z axes. (G) Design and
print part of a limb-mimic structure with soft muscle (G88), moderate skin (G70), and stiff bone (G0) as well as hollow channels. (H) The limb-mimic structure was easily compressed
in the thickness direction. (I) The limb-mimic structure was loaded heavyweight (1 kg) without obvious bending across the length direction (z axis). (J) Design and print part of a
small-scale artificial limb structure with soft muscle (G85) and stiff bone (G0). Scale bars, 1 cm. Photo credit: Xiao Kuang, Georgia Tech.

[Source / Images: ‘Grayscale digital light processing 3D printing for highly functionally graded materials’]

International Researchers Review Methods for 3D Printing Biomedical Sensors

Researchers from both China and India have come together to review the current 3D printed sensor scene, regarding the technology being used and applications and industries being impacted. Authors Tao Han, Sudip Kundu, Anindya Nag, and Yongzhao Xu published their findings recently in ‘3D Printed Sensors for Biomedical Applications: A Review.’

While manufacturing of sensors has continued to progress, obstacles have prevailed, and in many ways have stalled sensor fabrication from achieving its true potential in many applications. As the authors point out, sensors are all around us, but many are limited due to the cost involved in manufacturing, challenges regarding materials (such as silicon, also posing problems at low frequencies), and issues with temperature. More importantly, most sensors are not biocompatible, thus stilting advances in the medical arena.

With the advent of 3D printing, sensors can be designed in a more streamlined and affordable process, involving less steps in production and less hours needed in labor for creating accurate prototypes that can then be made digitally. 3D printed sensors are usually much stronger and more durable too and have shown promise for monitoring blood pressure and heart rate, respiration, temperature, brain activity, and more.

(A) Fused deposition modelling (B) Stereo-lithography (C) Polyjet Process (D) Selective laser
sintering (E) 3D Inkjet printing (F) Digital light processing.

Currently, the following processes have been used to make sensors successfully:

Fused deposition modelling (FDM)
Stereolithography (SLA)
Polyjet process
Selective laser sintering (SLS)
3D inkjet printing and DLP

“Among these six types, the most common type is the FDM one, which has been largely used to develop prototypes for electrochemical sensing purposes,” state the researchers. “Others like FDM, SLA and ink-jet printing have also been considered for forming prototypes since they can be developed with lower resolutions. Polyjet and SLS processes are mostly used for forming sensors which are employed for cell culture applications.”

FDM 3D printing has been popular among users for biomedical uses, with both AB and PLA materials, as well as alternatives like waxes and nylon. Bioprinting has also been successful, with researchers noting good cell viability and sustainability. The authors note, however, that disadvantages in using FDM 3D printing include lack of shape integrity and leakage when materials are not ‘properly tuned.’ Sensors have, however, been created for detecting glucose, cancer biomarkers, and other items like reactors for biological sample monitoring.

SLA 3D printing is useful due to its ability to create large-scale items. Researchers have used ABS to create more complex devices like biosensors and microfluidic devices for detecting pathogens. Disposable and portable electrochemical sensors have also been created, along with intricate components like a 3D printed microfluidic part for urinary protein quantification, comprised of a pushing valve, rotary valve, and torque-actuated pump.

a) Schematic illustration of separation of the captured bacteria by inertial focusing. (b)
Representation of dean vortices in a channel with trapezoid cross-section. (c) Photograph of the 3D
printed microfluidic device. Reproduced from Lee et al. [112].

In polyjet printing, a curing or hardening process creates parts—and like in FDM 3D printing, multiple nozzles can be used.

“Since multiple jetting heads are used for printing, this allows building multi-colored objects in a single structure. One of the main advantages of this process is that a high resolution of 16 µm can be achieved for the prototypes, having an accuracy of less than 0.1 mm.”

Using polyjet 3D printing, cell viability sensor-based fluidic devices have been created, along with other innovations such as leak-proof 3D printed storage devices. Other sensors have been created through polyjet 3D printing for ATP and dopamine sensing, along with physiological sensors, and electrochemical and biocompatible sensors.

SLS printing is used in AM processes with the use of metal powders:

A certain laser power is required to melt the periphery of the particles using the localised energy of a laser beam. The unused powder acts as a support structure for the 3D printed part. After scanning each layer, the structure is lowered to spread a new powder layer which can be scanned according to the computer-aided design (CAD) design. Not only metallic powder particles but also ceramics and polymers or combinations with each other can be used in SLS,” state the researchers.

Benefits in SLS 3D printing are that many different materials can be used—and precisely so—with powder available for recycling. Cell density sensors have been created, explain the authors, and they could be extended to manipulate cell ‘disruptions,’ distribute chemicals, and control enzymatic assays.

. Continuous recalibration of the 3D-printed Control Unit Adaptive P controller. Reproduced from Ude et al. [127]. (A) The 3D printed flask is used to control the pH of the solution using defined algorithm. (B) The interior of th3 3D printed flask. (C) Variation in the amplitude, pH levels and intensity of the scattered light with time.

3D inkjet printing offers benefit in creating strong, complex structures; for example, researchers have been successful in creating items such as a 3D printed bionic ear. Others have created items like actuator integrated heart structure-shaped 3D elastic multifunctional biomembranes for sensing spatial and temporal responses.

Image of the (A) fabricated 3D printed bionic ear and (B) 3D printed bionic ear during its vitro culture. (C) The viability of chondrocyte at different stages during the printing process. (D) Deviation of the weight of the printed ear over time in culture, where the ear consisted of the chondrocyte-seeded alginate or only alginate shown in red and blue colour respectively. (E) Histologic analysis of chondrocyte morphology done using H&E staining. (F) Neocartilaginous tissue
being Safranin O stained after 10 weeks of culture. Photographs (top) and fluorescent (bottom) images of (G) viability of the neo cartilaginous tissue being in contact with the antenna of the coil and (H) cross-section of the bionic ear showing the viability of the internal cartilaginous tissue in contact with the electrode. Reproduced from Mannoor et al.

DLP 3D printing is like that of SLA, but a projector screen flashes, projecting layers like images:

“Each 2D hardened layer is formed after exposing the liquid polymer to projector light under the safest conditions instead of making a layer with several laser scan paths,” state the researchers. “The process is repeated until the entire structure is fabricated.”

Items such as glucose biosensors, light-addressable potentiometric sensors, and semiconductor-based biosensor are a few devices that have been created so far with DLP 3D printing.

“Each of these processes has its own merits and demerits related to cost and time of fabrication, the type of materials that can be processed and prototypes that can be formed,” concluded the researchers. “A few of the current bottlenecks have also been mentioned, along with the possible remedial solutions to deal with them. Finally, a market survey has been presented about the expenditures on the different types of 3D printing techniques in the current scenario and in the upcoming years to develop sensors and other electronic appliances.”

3D printing has made a significant impact in the realm of electronics, however, and even more specifically, sensors. Over the years, we have followed a wide array of sensors created to improve monitoring and functionality in numerous applications, from fending off 3D printing cyberattacks to fabricating fiber optics or tending to simple but scientific matters like measuring the water intake of plants. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

(a) A 3D printed smartphone adaptor depicting its (b) 3D printed cartridge being composed
of reservoirs and sliding lid. (c) The assembled smartphone-based device for BL signal acquisition
and analysis. Reproduced from Cevenini.

[Source / Images: 3D Printed Sensors for Biomedical Applications: A Review]

atum3D Installs Operator Station Software and DLP Station 5 3D Printer at Sirris Technology Collective

Digital light processing (DLP) specialist and open platform 3D manufacturing company atum3D, based in the Netherlands, introduced the latest version of its intuitive Operator Station print preparation software, complete with proprietary MAGS AI technology, at formnext 2018. The software makes it easy to duplicate parts, or fill available build volume, and comes with a slicing preview feature, while MAGS AI will automatically adjust a part’s orientation and generate the necessary supports, based on surface markings made by the user.

Now the company has announced its first onsite installation of the newly updated software solution. Sirris, a Belgian industrial collective center started by the technology industry for the technology industry, provides companies with a high-tech testing infrastructure and is also a partner organization in the Family of the Future project. The collective, which also has a DLP Station 5 3D printer from atum3D, will expand its current offering with the updated Operator Station solution.

“A barrier for printing parts are often the high costs related to the monopoly of or restrictions of material suppliers,” explained Maxime Legrand, Engineer Additive Manufacturing at Sirris. “With this equipment Sirris wants to support companies in the development and the production of their new AM applications at an affordable cost due to the higher flexibility in potential printing materials. This will enable new possibilities that couldn’t be met before. This atum3D setup allows us to demonstrate it’s now possible to quickly create high quality prototypes and end-products with a wide range of different material properties in a cost-efficient way, all with an investment around the € 25k mark.”

Sirris is made up of 150 tech experts, who work together to help around 1,300 companies a year achieve success in their innovation projects. By combining atum3D’s updated Operator Station with the open platform of the DLP Station 5, the collective and the companies it assists will benefit from easier print preparation.

“Operator Station guides you through the job preparation steps, from importing and supporting a part to selecting a resin and from duplicating or filling the build platform to slicing and exporting the job for DLP Station,” said Legrand. “It’s incredibly easy to use.”

The latest release of Operator Station, which uses an algorithm to consider not only the part’s geometry but also its resin properties, also includes a new object scaling functionality.

“We are thrilled to add DLP Station 5 with Operator Station to the state-of-the-art solutions offered by this Belgian innovation leader. Preparing for print has never been easier, with Operator Station’s intuitive touch-ready user interface and atum3D’s proprietary MAGS AI technology, which takes an entirely new approach to print job preparation,” said Guy Nyssen, channel manager at atum3D.

By pairing Operator Station software with the DLP Station 5, which features high accuracy, a free selection of build materials, and print speed up to 90 mm an hour, print preparation is a breeze, especially for new users like those at Sirris.

atum3D delivered the Operator Station to the Sirris Liège location, and installed both the hardware and the software there for the collective. In addition, the company also provided a user training session, which the new users at Sirris found to be “very self-explanatory.”

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[Images provided by atum3D]