Recycling Residual Resin in 3D Printing Processes
9 patents in this list
Updated:
In industrial 3D printing operations, up to 40% of build material can end up as waste - from support structures, failed prints, and residual uncured resin. For specialized engineering resins costing $300-500 per liter, this represents both a significant economic loss and an environmental challenge, as many photopolymers contain toxic components that require special disposal.
The fundamental challenge lies in developing recycling methods that can separate and recover pure base materials while managing cross-linked polymers, photoinitiators, and other additives that affect material properties.
This page brings together solutions from recent research—including solvent-based polymer recovery systems, deblocking chemistry for prepolymer regeneration, and in-printer waste material conditioning. These and other approaches focus on maintaining material quality through multiple recycling cycles while making recovery economically viable at production scale.
1. Method for Solvent-Based Recovery and Pelletization of Polyolefin Polymer from 3D Printed Objects
Hewlett-Packard Development Company, L.P., 2023
Recycling polyolefin polymer from failed 3D printed objects to reduce waste and environmental impact. Recycling involves dissolving the polymer in a solvent, separating any fusing compound, and evaporating the solvent to recover pure polymer. The fusing compound is removed because it's not easily recycled due to residual components in the 3D printed objects. The recycled polymer can then be used in injection molding applications. The pelletizing step involves grinding the 3D printed objects into small pieces and extruding them into injection molding pellets. This allows recycling of the polymer even when it has failed in the 3D printer.
2. Method for Producing Metal Castings Using 3D Printed Molds with Inorganic Binder Coating
Lift Technology, 2023
A method for producing metal castings using 3D printing and inorganic binders. The method selects a shape-forming material selectively based on manufacturing and shape characteristics. The material is 3D printed to create a mold. An inorganic binder solution with at least 51% inorganic material is coated onto the printed mold. The mold is dehydrated and filled with hot metal. After cooling, the metal part is removed, and the mold is reclaimed. The inorganic binder and shape-forming material are reused. The inorganic binder allows dehydration and gas-free metal filling.
3. 3D Printing System with Single-Material Layer Resin Recycle Mechanism
INTERNATIONAL BUSINESS MACHINES CORPORATION, 2023
Reducing waste during 3D printing by recycling excess resin if only one type is used in a layer. After printing and leveling a single-material layer, the leveled-off material is returned to the printer for reuse. But if a layer has multiple resins, the excess is discarded. This avoids wasting expensive and toxic resin by recycling what can be reused. It also reduces costs and environmental impact.
4. Polymer Recovery Process from 3D Printed Objects Using Selective Solvent Dissolution
HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P., 2023
A recycling method for 3D printed objects made of polymers like nylon (polyamide) recovers the polymer material instead of disposal. Recycling involves dissolving the polymer in a solvent that dissolves the polyamide but not the fusing agent, separating the polymer from the fusing agent and solvent, and evaporating the solvent to get pure recycled polymer. This allows the fusing agent components like carbon black and fusing compounds to be separated from the polymer for reuse. The solvent can be cresol or fluorinated alcohol.
5. Additive Manufacturing Resin with Reactive Blocked Prepolymer for Recycling
CARBON, INC, 2023
Additive manufacturing resins that enable the recycling of 3D printed objects. The resin is a single-cure formulation containing a reactive blocked prepolymer, crosslinker, photoinitiator, etc. The reactive blocked prepolymer has reactive end groups that can be deblocked during recycling. When the printed object is ground into particles, the deblocked prepolymer can be regenerated by heating with a reactive blocking agent. This allows extracting and reusing the prepolymer instead of wasting it in the printed object.
6. Recycling Process for Stereolithography-Fabricated Objects via Solvent Extraction of Crosslinked Polymers
CARBON, INC., 2023
Recycling method for objects made by stereolithography additive manufacturing that allows reuse of the thermoplastic material. The recycling involves extracting the crosslinked heat-polymerized portion from the object using a solvent, leaving the uncrosslinked light-polymerized portion behind. The solvent-extracted crosslinked polymer is then separated and reused, while the remaining light-polymerized portion can be thermoformed into new objects.
7. 3D Printer System with Integrated Build Material Recovery and Reconditioning Mechanism
HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P., 2022
3D printer system with a recycling system to recover and reuse incidental and non-solidified build material during and after print jobs. The system collects unused powder or granules from the build area, cleans and conditions them, and then feeds the recycled material back into the printer for future builds. This reduces waste and saves costs compared to continuously replacing the full-built material container.
8. Integrated 3D Printer Waste Ink Curing System with UV-Activated Cartridge
Stratasys Ltd., 2021
Environmentally safe waste ink disposal for 3D printers that avoids the need for separate waste containers and shipping. The method involves collecting the excess ink during printing and curing it inside the printer. This is done using a dedicated cartridge with drip points for ink distribution and UV LEDs for curing. The cartridge fills with ink and then, and the UV cures it when full. This prevents hazardous ink waste from accumulating in the printer. The curing also prevents stalactites/stalagmites formation. The cartridge is periodically replaced when full.
9. Method for Regenerating Reactive Blocked Prepolymers from Ground Additively Manufactured Resin Objects
Carbon, Inc., 2021
Recycling additively manufactured objects made from resins containing reactive blocked prepolymers. The objects are ground into particulate form and mixed with additional blocking agents to regenerate the original reactive blocked prepolymer. This regenerated resin can then be used for additive manufacturing. The reactive blocking agents polymerize during initial curing and are trapped inside the final part. Extracting the ground particulate allows recovering the blocked prepolymer and regenerating the resin.
Creating recyclable resin compositions, sorting multi-material waste streams, and purifying contaminated resin are some of the aspects of resin recycling that are handled by the technologies provided. In an effort to cut waste and conserve resources, as these technologies develop, so will sustainable 3D printing methods.
