Amorphous Polymer 3D Printing Selectivity via Coalescent Fluids

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Amorphous polymers pose challenges in 3D printing due to their lack of a specific melting point, leading to poor selectivity and caking issues, as they soften gradually over a range of temperatures, making it difficult to form fused portions without fusing neighboring particles.

Innovation Solution

The use of coalescent fluids containing viscosity reducing agents that lower the viscosity of amorphous polymer powders, allowing for selective fusion at lower temperatures while keeping surrounding particles unfused, by combining with thermal fusing agents to absorb energy from electromagnetic radiation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If electromagnetic radiation is applied to fuse amorphous polymer powder, then fusion occurs, but selectivity between fused and unfused portions deteriorates due to gradual softening over temperature range

Engineering Contradiction:
ImproveselectivityVSAvoidtemperature control
Core Design Contradiction:
Manufacturing precisionVSTemperature

Solution Approach 1:

The patent changes the physical-chemical parameters of the polymer powder by incorporating particles with different thermal properties (metal particles, ceramic particles, or polymer particles with different glass transition temperatures). This allows the composite powder to have a more defined fusion temperature range, improving selectivity during electromagnetic radiation exposure while maintaining controllable temperature behavior.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates composite polymer powder by combining amorphous polymer particles with secondary particles (metal, ceramic, or different polymer types). This composite structure enables differential response to electromagnetic radiation, where the secondary particles affect the thermal and optical properties to achieve better fusion selectivity and reduce unwanted softening of surrounding particles.

Inventive Principle:
Principle #40Composite materials

2Productivity

If thermal fusing agents are used to absorb electromagnetic radiation energy, then fusion efficiency improves, but energy consumption increases

Engineering Contradiction:
Improvefusion efficiencyVSAvoidenergy consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent applies thermal fusing agents selectively only to the regions where fusion is desired, rather than uniformly throughout the entire powder bed. This localized application ensures that electromagnetic radiation energy is absorbed primarily where needed, improving fusion efficiency while minimizing overall energy consumption by avoiding unnecessary heating of surrounding areas.

Inventive Principle:
Principle #3Local quality

3Manufacturing precision

If printing temperature is increased to ensure complete fusion, then fusion quality improves, but caking of surrounding particles increases

Engineering Contradiction:
Improvefusion qualityVSAvoidcaking
Core Design Contradiction:
Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The patent modifies the thermal parameters of the polymer powder through composite formulation, creating materials that maintain structural integrity at higher temperatures while achieving complete fusion at the printed locations. The secondary particles (metal, ceramic, or high-Tg polymer) provide thermal stability that prevents surrounding particles from caking even when printing temperature is increased to ensure complete fusion quality.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach improves the selectivity between fused and unfused portions, reducing caking and enhancing the quality of 3D printed parts by allowing precise control over the fusion process, even with amorphous polymers that lack a characteristic melting point.

Implementation Method 1

A thermal fusing agent can be combined with the viscosity reducing agent. The thermal fusing agent can absorb energy from an electromagnetic radiation fusing source, such as a fusing lamp, to a temperature sufficient to fuse the printed portion of the amorphous polymer powder.

Methodology Applied
Scientific EffectAbsorption of electromagnetic radiation: Absorption (EM radiation)

Implementation Method 2

The thermal coalescent fluid can absorb more energy from the fusing source, e.g., typically the entire bed. Absorbed fusing light energy can be converted to thermal energy, causing the printed portions of the powder to melt and coalesce.

Methodology Applied
Scientific EffectConversion of electromagnetic energy to thermal energy: Dielectric Heating

Implementation Method 3

The coalescent fluid can include a viscosity reducing agent that lowers the viscosity of the amorphous polymer powder. The viscosity reducing agent can enable fusion of the amorphous polymer powder at a reduced temperature.

Methodology Applied
Scientific EffectViscosity reduction:

Implementation Method 4

The bed can be exposed to an electromagnetic radiation fusing source, e.g., typically the entire bed. Absorbed fusing light energy can be converted to thermal energy, causing the printed portions of the powder to melt and coalesce.

Methodology Applied
Scientific EffectElectromagnetic radiation heating: Dielectric Heating

Data Source

PatentEP3455053B1Three-dimensional printing system and three-dimensional printing method
Publication Date: 2023.01.04 HEWLETT PACKARD DEVELOPMENT COMPANY LP
  • EP3455053B1 patent drawingFigure 1A~1B
  • EP3455053B1 patent drawingFigure 2~3
  • EP3455053B1 patent drawingFigure 4~5

AI summary

The present disclosure is drawn material sets, coalescent fluids, and 3-dimensional printing systems. An example material set can include an amorphous polymer powder having an average particle size from 1 micron to 300 microns, and a coalescent fluid including a viscosity reducing agent.