In depth 3D Printing and Additive Manufacturing

Our Goals are your Own Goals, Your Benefits

The objective of 3Dresyns is to offer sensible and cost effective solutions to unmet market needs and develop 3D functional materials and processes for the development of better, safer and more ecological materials and production processes at the lowest possible cost and human impact on the environment.

“3Dresyns offers a full range of safe & functional materials with multiple properties, functionalities and colors: from durable tough and elastic to sacrificial materials for direct and indirect additive manufacturing"

Other key goals of 3Dresyns is the development of biodegradable and durable biocompatible safe materials,  based on biological and renewable sources.

Our biocompatible resins have non toxic pictograms and are ultra safe for handling and final users. Our wide range of monomer free safe materials ensure the safety of the end user since the potential risk of monomer migration and absorption by the body is eliminated.

3D printing is a fast evolving technology where existing and new technologies and production processes are continuously developed and improved for making better and safer materials at the lowest possible production costs.

If you are interested in making things and feel like a "homo faber" or "working man/woman" then read this chapter for making things differently and efficiently.

Depending on your goals some technologies and processes may fit better than others. Sincerely speaking, curiously some cost effective technologies and processes have specific advantages and benefits over more expensive alternative processes.

Direct & Indirect Additive Manufacturing AM

Simply, addtitive manufacturing can be divided in two types: Direct and Indirect Additive Manufacturing.

Direct AM

Direct additive manufacturing of 3D printed products, to say: plastics, ceramics, metals, polymers, and exotic materials have some benefits and limitations. The following Table summarizes the direct manufacturing/production processes where Additive Manufacturing with Stereolithography SLA, DLP, LCD and Inkjet 3D printing technologies are used:

 3Dresin

Process

Product

Properties

Benefits

Limitations 

3D resins

Direct AM

3D resin objects, optionally filled with functional additives, ceramics, metals, polymers, and exotic  materials

Properties of cured resins/polymers with extra performance provided by additives, ceramics, metals, polymers, and exotic  materials 

Cost effective direct production for short runs of 3D printed materials

 Cost effective only for short run productions

Direct printing of sintering ceramics, metals, polymers, and exotic materials

Resin printing, debinding & sintering of ceramics, metals, polymers, and exotic  materials

Sintered ceramics, metals, polymers, and exotic  materials

Properties of sintered technical ceramics, metals, polymers

 

Direct production of short runs of pure ceramic objects

 

 Expensive printers, difficult tuning, slower debinding, smaller feature sizes (max.1-3 mm), more microcracking during debinding than Indirect production


 

Indirect AM: 2 steps/processes

Indirect additive manufacturing of products, to say: resins, plastics, ceramics, metals, polymers, and exotic materials have certain benefits and limitations. Indirect manufacturing requires the usage of castable materials, such as models, durable and/or sacrificial molds, etc. 

  • Printing of injection molds by SLA, DLP, LCD and Inkjet 3D printing + injection or casting resins, plastics, ceramics, metals, polymers, and exotic materials

Types of injection molds:

The injection of Powder Injection Molding PIM binder slurries (including ceramic, metal, polymers, and exotic material feedstocks) in 3D printed durable, and/or sacrificial molds (or printed by high temperature powder jetting) has unique benefits in comparison to direct printing of highly loaded 3D photopolymer resins with powders.

The following Table summarizes the existing and the innovative Indirect Additive Manufacturing / Production processes where SLA, DLP, LCD and Inkjet 3D printing technologies are used:

3D resin

Process

Product

Properties

Benefits

Limitations

Castable 3D resins

Direct investment Casting  DC

Metal cast objects

Typical properties of Cast Metals

Cost effective direct investment casting of metal objects

 Most castable competitor's 3D resins suffer from imperfections of fine detail finishes

Non Castable  3D resins

Indirect investment casting IC

Metal cast objects

Typical properties of Cast metals

 

 Less cost effective indirect investment casting production of metal objects  with very high resolution Slower process since there are several time consuming production steps
Durable injection molding 3D resins Direct plastic, and sintering ceramic, metal, polymer (such as polyimide),  and exotic powder feedstock injection in 3D printed durable injection molds Plastics, ceramics, metals, polymers, and exotic materials Properties of plastics, ceramics, metals, polymers, and exotic materials Cost effective production of durable injection molds for simple shaped plastic, ceramic, metal, polymer, and exotic material injection Not suitable for complex intertwined shapes
Easy breakable sacrificial 3D resins Direct plastic injection in 3D printed easy breakable sacrificial molds Soft plastic, rubber or silicone objects Properties of soft plastics, rubbers, and silicones

Cost effective production of easy breakable sacrificial molds* for complex shaped soft plastic, rubber and silicone injection molding

 Not needed for simple 3d printed shapes, mold is lost during production
Sacrificial 3D resins Direct plastic, and sintering ceramic, metal, polymer (such as polyimide),  and exotic powder feedstock injection in 3D printed sacrificial injection molds Plastics, ceramics, metals, polymers, and exotic materials Properties of plastics, ceramics, metals, polymers, and exotic materials Cost effective production of sacrificial injection molds for complex shaped plastic, ceramic, metal, polymer, and exotic material injection Not needed for simple 3D printed shapes, mold is lost during production

Note: sacrificial molds are needed for making intricate complex shapes where the mold and the injected material are entangled 

Manufacturing of plastics with Stereolithography

Direct and Indirect additive manufacturing of functional plastic materials can be undertaken by Stereolithography and Inkjet printing with high resolution printing with an accuracy 5-10 times higher than Fused Deposition Modeling FDM printing.

Our photopolymer 3D resins allow the direct manufacturing and printing of safe functional materials by Stereolithography and Inkjet printing. They are safe for printers and final users and have high mechanical properties, which are taylored to each specific application requirements, allowing direct additive manufacturing of the toughest printable 3D resins such as:

Required equipment and materials for direct additive manufacturing of functional plastic materials:

Indirect additive manufacturing of plastics with Stereolithography

On the other hand, our 3D resins can be used in Indirect additive manufacturing for:

Required equipment and materials for indirect manufacturing by injection of plastic resins, filled with functional additives, ceramics, metals, polymers, and exotic materials, to produce functional resin composites: 

  • conventional resins for injection into the 3D printed molds

Alternative Technologies: Direct additive manufacturing by SLS 3D printing with non-photoreactive binder powders

  • Selective Laser Sintering SLS where layers of typically plastic or metal powders are selectively laser sintered to create 3D printed objects
  • 3Dresyns has developed universal bio based non-photoreactive powder binders for easy physical mixing with any Ceramic, Metal, Polymer/Plastic, or exotic powder or fiber for plastic / polymer powder Selective Laser Printing SLS, also known as Cold Metal Fusion (CMF), Cold Ceramic Fusion (CCF), and Cold Polymer Fusion (CPF): Non photoreactive Resin Powder Binders for SLS printing of Ceramic, Metal & Polymer powders. This technology can also be considered Direct AM since SLS prints keep their original shape (mold free system), despite shrinking and needing chemical and thermal debinding and sintering after printing

When is worth using Direct or Indirect Additive Manufacturing AM?

The answer depends on:

  • number of produced parts
  • relative costs
  • functionality: performance properties required 
  • biocompatibility requirements

When is justified the "2 step" indirect manufacturing? some benefits of Indirect manufacturing with molds and resin Injection or casting are:

  • increased biocompatibility -unless our "monomer free" biocompatible 3Dresyns are directly printed by SLA since do not contain toxic monomers which are prone to cause skin irritation, allergic reactions and other health hazards
  • the best injected reinforced plastics have flexural strengths >200 MPa
    • the toughest 3D printed resins like 3Dresyn PEEK-like have flexural strengths c. 110-130 MPa
  • higher mechanical properties for most injected plastics, unless our 3Dresyn Nylon-like and 3Dresyns like best functional engineering plastics are directly printed by SLA, DLP & LCD
  • versatility, since any conventional or traditional thermoplastic or thermoset "injection molding and casting resins" can be injected or cast by gravity in 3D printed sacrificial or durable molds
  • lower raw materials costs, since conventional or traditional thermoplastic or thermoset "injection molding and casting resins" are cheaper than SLA,DLP, LCD and Inkjet 3D resins. 
  • time savings, since the tuning in the printers of SLA,DLP, LCD and Inkjet 3D resins has to be done only once and not for each individual 3D resin used in direct manufacturing
  • lower certification costs for dental and biomedical devices, since the existing certifications of non photoreactive traditional  biocompatible thermoplastics materials may be used since no photochemical reaction occurs during their injection in molds, reducing the risk of leaving unreacted monomers and byproducts as it may happen with prints made by direct manufacturing with monomer based 3D resins if not fully cured and cleansed

      Direct & Indirect AM of ceramic, metal, polymer, and exotic powder materials

      Indirect manufacturing of ceramics, metals, polymers, and exotic nano and micron powders using durable or sacrificial molds printed with SLA,DLP, LCD and Inkjet 3D resins, permits the manufacture of ceramics, metals, polymers, and exotic materials by injection of feedstocks / slurries by traditional injection molding (CIM, MIM, & PIM) with the advantage of being more cost competitive than metal molds manufactured by CNC.

      On the other hand, direct AM of ceramics, metals, polymers, and exotic materials with stereolithography SLA DLP, LCD and jetting printers has presented great technological challenges and limitations, such as:

      • adjusting the printing parameters for each highly loaded powder material 3D printable resin is a slow and complex process. Opaque materials limit printing to thin layers of a few microns, such as 10-20 microns in direct 3D SLA & DLP printing of stainless steel.
      • relatively slower debinding and sintering process, making the production process too slow (up to 7 days) vs the faster debinding of traditional CIM, MIM & PIM, because a higher percentage of photoreactive 3D resin (c. 15% by weight) is required to provide flow and printability by direct printing vs the lower percentage (c. 5-10%) typically used in traditional CIM and MIM
      • reduced printed thickness down to 1-3 mm. This limitation is due to microcracking caused by the high % of photoreactive 3D resin used in the ceramic and metal 3D resin printed with stereolithography SLA & DLP and jetting printers vs traditional CIM and MIM

      Benefits of Indirect AM of ceramic, metal, polymer, and exotic materials

      Indirect AM of:

      in durable and sacrificial injection molds printed with SLA DLP, LCD and Inkjet 3D resins versus Direct AM by:

      has several technical and production advantages since the usage of traditional feedstocks shows process and property improvements such as:
      • less risk of microcracking
      • no thickness limitation
      • higher debinding and sintering speed
      • 100% isotropy vs anisotropy of direct printing of ceramics "layer by layer"
      • improved final properties: higher density and lower microporosity of sintered materials 
      • full range of traditional technical ceramics, metals, polymers, and exotic materials can be injected using traditional CIM, MIM & PIM feedstocks
      • higher sintering density and isotropy, as well as lower microporosity vs metal Selective Laser Sintering SLS and direct printing of ceramics and metals by SLA and jetting printing
      • less productivity limitations, much faster debinding and sintering times without the limitation of thickness occurring with direct ceramic and metal SLA and jetting printing
      • lower costs since our 3D resins allow the printing of sacrificial or durable molds even with affordable SLA DLP LCD printers with prices ranging from 200 to 2,000 Euros with traditional  injection molding machines (300-3000 Euro per injection machine) and with traditional ceramic and metal feedstocks with much cheaper overall costs than direct ceramic and metal SLA 3D resin printing

      Benefits of 3Dresyns SLA DLP & LCD 3D resins for Direct AM of ceramic, metal, polymer, and exotic powder materials

      3Dresyns has developed fast debinding 3D resins with the aim of providing solutions to the limitations of direct printing of ceramics, metals, polymers, and exotic materials by 3D stereolithography and jetting. Our fast debinding 3D resins allow their use as:

      • water and non water soluble 3Dresins for dispersing your chosen ceramics and metals for reducing the debinding time in direct printing of ceramics, metals, polymers, and exotic materials with SLA and Jetting

      Analysis of the required equipment and materials for direct manufacturing of ceramics and metals by SLA:

      • Dedicated ceramic and metal SLA printers for printing ceramics and metals 3D resins with prices ranging from 80.000-350.000 Euro
      • Ceramic and metal 3D resins for direct printing ceramic and metal parts in green state
      • furnace for debinding and sintering

      Benefits of 3Dresyns SLA DLP & LCD 3D resins for Indirect AM of ceramic, metal, polymer, and exotic powder materials

      Our 3D resins for printing durable and sacrificial injection molds for injection of traditional ceramic, metal, polymer (such as polyimide), and exotic material feedstocks:

      • durable molds are recommended for simple not intertwined shapes between the mold and the produced parts
      • sacrificial molds are recommended for intertwined shapes between the mold and the produced parts

      Required equipment and materials for indirect manufacturing of ceramic, metal, polymer (such as polyimide), and exotic material feedstocks:

      All the mentioned feedstock materials can be supplied as solids at room temperature in metal cartridges of 25 mm external diameter for direct injection in low cost manual injection machines such as this type of manual injection equipment:

        Example of a 3D Printed coin with a water soluble printed resin with a low cost LCD 3D printer

        Coin in water before its dissolution

        Coin dissolved in water after several hours

        Benefits of 3Dresyns SLS bio-based binder powders for Direct AM of ceramic, metal, polymer, and exotic powder materials

        Powder Binders for SLS Cold Metal, Ceramic & Polymer Fusion are ideal for SLS printing of traditional ceramic, metal, polymer (such as polyimide), and exotic materials, exhibiting these features and benefits:

        • universal water or solvent soluble solvent debindable Eco bio-based Powder Binders for Selective Laser Sintering SLS printing of any (your chosen) Ceramic, Metal, Polymer, and exotic powder or fiber by Cold Metal Fusion (CMF) , Cold Ceramic Fusion (CCF) & Cold Polymer Fusion CPF
        • bio-based powders with over 90% Bio content  for eco friendly SLS printing, debinding and sintering of ceramics, metals, polymers (such as PTFE and PEEK), and exotic powders (including nanowires, microfibers, etc)
        • easy physical dry powder mixing and wetting with ceramics, metals, polymers and exotic powders with low cost dry powder mixing equipment
        • excellent adhesion, uniformity and stability (without gravitational separation) after mixing with micron and submicron ceramics, metals, polymers, such as polyimide, and exotic powders  (including nanowires, microfibers, etc)
        • ceramic, metal, polymer, and exotic powder (including nanowires, microfibers, etc) additions can be up to 60% volume concentrations (lower for nanoparticles, nano wires and microfibers)
        • printable by most plastic / polymer powder SLS printers
        • soluble in water or in Debinding Solution EDS1 Bio at 90ºC for "cold" water or eco solvent debinding and sintering without imperfections nor cracking
        • promote controlled and reproducible process shrinkage which depends on final added % powder ratio
        • minimum expansion coefficient to prevent micro-fractures
        • very high resolution up to 50 microns of final products (depending on the particle size of the chosen ceramic, metal, polymer, or exotic powder or fiber)

        "Our goal in 3D printing: any color, any material, any process, any finish, any end use application and any SLA, DLP, LCD and Inkjet 3D printer"

        "3Dresyns offers the widest range of safe functional Stereolithography SLA, DLP, LCD and Inkjet 3D resins for safe printing of functional and biocompatible materials"

        How To Buy: Online Shopping of 3Dresyns in just few clicks: the widest range of 3D resins in the market to help you to attain the desired finish and quality of your 3D prints.

        “The aim of 3Dresyns is to provide the best Stereolithography and Inkjet resins and find solutions to unmet 3D printing market needs for any material, process and application”

        "3Dresyns is committed to innovation and development of safe and biocompatible 3Dresyns with safe synthetic and bio based raw materials from renewable sources"