US-12616197-B2 - Three-dimensional printing

US12616197B2US 12616197 B2US12616197 B2US 12616197B2US-12616197-B2

Abstract

An agent for three-dimensional (3D) printing includes at least 3 wt % active, based on a total weight of the agent, of a paraben selected from the group consisting of methyl paraben, ethyl paraben, propyl paraben, butyl paraben, isopropyl paraben, isobutyl paraben, heptyl paraben, benzyl paraben, salts thereof, and combinations thereof; and an aqueous vehicle. The aqueous vehicle includes up to 85 wt % active, based on the total weight of the agent, of a co-solvent package including at least one co-solvent present in an amount sufficient to increase a solubility of the paraben in the aqueous vehicle; and a balance of water.

Inventors

Emre Hiro Discekici
Shannon Reuben Woodruff
Graciela E. Negri Jimenez

Assignees

PERIDOT PRINT LLC

Dates

Publication Date: 20260505
Application Date: 20210929

Claims (15)

1 . An anti-microbial agent for three-dimensional (3D) printing, comprising: at least 3 wt % active, based on a total weight of the anti-microbial agent, of a paraben selected from the group consisting of methyl paraben, ethyl paraben, propyl paraben, butyl paraben, isopropyl paraben, isobutyl paraben, heptyl paraben, benzyl paraben, salts thereof, and combinations thereof; and an aqueous vehicle including: up to 85 wt % active, based on the total weight of the anti-microbial agent, of a co-solvent package including at least one co-solvent present in an amount sufficient to increase a solubility of the paraben in the aqueous vehicle; and a balance of water.
2 . The anti-microbial agent as defined in claim 1 wherein the paraben is present in an amount ranging from at least 3 wt % active to about 15 wt % active based on the total weight of the anti-microbial agent.
3 . The anti-microbial agent as defined in claim 1 wherein the at least one co-solvent consists of a phenol ether and an alcohol.
4 . The anti-microbial agent as defined in claim 3 wherein: the phenol ether is 2-phenoxyethanol or 2-phenylethanol present in an amount ranging from at least 0.5 wt % active to about 3 wt % active based on the total weight of the anti-microbial agent; and the alcohol is selected from the group consisting of propylene glycol, glycerol, polyethylene glycol, and a diol, and is present in an amount ranging from about 5 wt % active to about 80 wt % active, based on the total weight of the anti-microbial agent.
5 . The anti-microbial agent as defined in claim 3 wherein: the phenol ether is 2-phenoxyethanol or 2-phenylethanol present in an amount ranging from at least 0.5 wt % active to about 3 wt % active based on the total weight of the anti-microbial agent; the alcohol consists of a first alcohol and a second alcohol; the first alcohol is selected from the group consisting of methanol, ethanol, and glycerol present in an amount ranging from about 5 wt % active to about 10 wt % active, based on the total weight of the anti-microbial agent; and the second alcohol is propylene glycol present in an amount ranging from about 5 wt % active to about 75 wt % active, based on the total weight of the anti-microbial agent.
6 . The anti-microbial agent as defined in claim 3 wherein: the phenol ether is 2-phenoxyethanol or 2-phenylethanol present in an amount ranging from at least 1 wt % active to about 3 wt % active based on the total weight of the anti-microbial agent; the alcohol consists of a first alcohol and a second alcohol; the first alcohol is ethanol present in an amount ranging from about 5 wt % active to about 10 wt % active, based on the total weight of the anti-microbial agent; and the second alcohol is propylene glycol present in an amount ranging from about 30 wt % active to about 50 wt % active, based on the total weight of the anti-microbial agent.
7 . The anti-microbial agent as defined in claim 1 , further comprising a surfactant.
8 . The anti-microbial agent as defined in claim 1 , further comprising a radiation absorbing material.
9 . The anti-microbial agent as defined in claim 8 wherein the radiation absorbing material is selected from the group consisting of an infrared radiation absorbing material and an ultraviolet radiation absorbing material.
10 . The anti-microbial agent as defined in claim 1 wherein the anti-microbial agent consists of the paraben, the aqueous vehicle, an optional surfactant, and an optional radiation absorbing material.
11 . A method for three-dimensional (3D) printing, comprising: applying a polymeric build material composition to form a build material layer; based on a digital 3D object model of the 3D object, selectively applying a fusing agent on at least a portion of the build material layer; based on the digital 3D object model, selectively applying an anti-microbial agent on the at least a portion of the build material layer, the anti-microbial agent including: at least 3 wt % active, based on a total weight of the anti-microbial agent, of a paraben selected from the group consisting of methyl paraben, ethyl paraben, propyl paraben, butyl paraben, isopropyl paraben, isobutyl paraben, heptyl paraben, benzyl paraben, salts thereof, and combinations thereof; and an aqueous vehicle including: up to 85 wt % active, based on the total weight of the anti-microbial agent, of a co-solvent package including at least one co-solvent present in an amount sufficient to increase a solubility of the paraben in the aqueous vehicle; and a balance of water; and exposing the build material layer to electromagnetic radiation to coalesce the at least the portion to form a layer of a 3D object that exhibits anti-microbial properties.
12 . The method as defined in claim 11 wherein the fusing agent and the anti-microbial agent are a combined agent and the selective application occurs simultaneously.
13 . The method as defined in claim 11 wherein the fusing agent and the anti-microbial agent are sequentially applied over multiple printing passes.
14 . The method as defined in claim 11 , further comprising: iteratively applying individual build material layers of the polymeric build material composition; based on the digital 3D object model, selectively applying the fusing agent and the anti-microbial agent to at least some of the individual build material layers to define individually patterned layers; and iteratively exposing the individually patterned layers to the electromagnetic radiation to form individual object layers.
15 . A 3D printed article, comprising: coalesced polymeric build material; and at least 0.1 wt %, based on a total weight of the 3D printed article, of a paraben selected from the group consisting of methyl paraben, ethyl paraben, propyl paraben, butyl paraben, isopropyl paraben, isobutyl paraben, heptyl paraben, benzyl paraben, salts thereof, and combinations thereof.

Description

BACKGROUND Three-dimensional (3D) printing is an additive manufacturing process used to make three-dimensional solid parts from a digital model. 3D printing techniques are considered additive manufacturing processes because they involve the application of successive layers of material (which, in some examples, may include build material, binder and/or other printing liquid(s), or combinations thereof). This is unlike traditional machining processes, which often rely upon the removal of material to create the final part. 3D printing is often used in rapid product prototyping, mold generation, mold master generation, and short run manufacturing for mass personalization and customization of goods. BRIEF DESCRIPTION OF THE DRAWINGS Features of examples of the present disclosure will become apparent by reference to the following detailed description and drawings, in which like reference numerals correspond to similar, though perhaps not identical, components. For the sake of brevity, reference numerals or features having a previously described function may or may not be described in connection with other drawings in which they appear. FIG. 1 is a schematic diagram illustrating an example 3D printing technique; FIG. 2 is a schematic diagram illustrating another example 3D printing technique; FIG. 3 is a schematic, cross-sectional view, taken in the Y-Z plane, of an example of a 3D printed object printed from the bottom to the top on a build area platform having an X-Y plane; FIG. 4 is a schematic, cross-sectional view, taken in the Y-Z plane, of another example of a 3D printed object printed from the bottom to the top on a build area platform having an X-Y plane; and FIG. 5 is a graph depicting the % Strain at break of a control 3D object printed with no anti-microbial agent, and three 3D objects printed with three different anti-microbial agents. DETAILED DESCRIPTION Some examples of three-dimensional (3D) printing may utilize a fusing agent (including an electromagnetic radiation absorbing material) to pattern polymeric build material. In these examples, an entire layer of the polymeric build material is exposed to electromagnetic radiation, but the patterned region (which, in some instances, is less than the entire layer) of the polymeric build material is fused/coalesced and hardened to become a layer of a 3D part. In the patterned region, the fusing agent is capable of at least partially penetrating into voids between the polymeric build material particles, and is also capable of spreading onto the exterior surface of the polymeric build material particles. This fusing agent is capable of absorbing radiation and converting the absorbed radiation to thermal energy, which in turn fuses/coalesces the polymeric build material that is in contact with the fusing agent. Fusing/coalescing causes the polymeric build material to join or blend to form a single entity (i.e., the layer of the 3D part). Fusing/coalescing may involve at least partial thermal merging, melting, binding, and/or some other mechanism that coalesces the polymeric build material to form the layer of the 3D printed polymeric object. An agent is disclosed herein that can be used to impart anti-microbial characteristics to the 3D printed polymeric object. Thus, this agent may be referred to herein as an anti-microbial agent. The agent includes a paraben and a co-solvent package that increases the paraben's solubility in water, which renders it particularly suitable for incorporation into an aqueous vehicle. The resulting agent can be dispensed from an inkjet printhead, which enables the agent, and thus the paraben, to be controllably applied at the voxel level. At least some of the paraben remains in the 3D printed polymeric object after solvent removal and coalescence. As little as 0.2 wt % of the paraben can provide significant anti-microbial resistance against a variety of different bacteria strains. The mitigation of microbe growth can also mitigate malodor. Thus, the agent disclosed herein may be useful in generating a variety of 3D printed polymeric objects, such as, for example, orthotics and other footwear applications. Throughout this disclosure, a weight percentage that is referred to as “wt % active” refers to the loading of an active component of a dispersion or other formulation that is present, e.g., in the agent, fusing agent, etc. For example, a surfactant may be present in a water-based formulation (e.g., stock solution or dispersion) before being incorporated into the agent vehicle. In this example, the wt % actives of the surfactant accounts for the loading (as a weight percent) of the surfactant molecules that are present in the agent, and does not account for the weight of the other components (e.g., water, etc.) that are present in the stock solution or dispersion with the surfactant molecules. The term “wt %,” without the term actives, refers to the loading (in the fusing agent, etc.) of a 100% active component that does not i