Coalescing agent for three-dimensional (3D) printing

• US 10,640,661 B2
• Filed: 09/29/2014
• Issued: 05/05/2020
• Est. Priority Date: 09/29/2014
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Prasad, Keshava A., Emamjomeh, Ali, Haddick, Glenn Thomas
• Primary Examiner(s): Butcher, Robert T
• Application Number:
  US15/511,543
• Publication Number:
  US 20170247552A1
• Time in Patent Office: 2,045 Days
• Field of Search: None
• CPC Class Codes: B29C 64/00 Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B29C 64/386 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B29K 2077/00 Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: B41J 2/0458 controlling heads based on heating elements forming bubbles
• CPC Class Codes: B41M 5/0023 Digital printing methods characterised by the inks used inks per se C09D11/00
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08L 101/00 Compositions of unspecified macromolecular compounds
• CPC Class Codes: C09D 11/03 characterised by features other than the chemical nature of the binder
• CPC Class Codes: C09D 11/033 characterised by the solvent
• CPC Class Codes: C09D 11/037 characterised by the pigment
• CPC Class Codes: C09D 11/10 based on artificial resins
• CPC Class Codes: C09D 11/102 containing macromolecular compounds obtained by reactions other than those only involving unsaturated carbon-to-carbon bonds
• CPC Class Codes: C09D 11/107 from unsaturated acids or derivatives thereof
• CPC Class Codes: C09D 11/324 : containing carbon black
• CPC Class Codes: C09D 11/38 : characterised by non-macromolecular additives other than solvents, pigments or dyes

Abstract

A coalescing agent for three-dimensional (3D) printing includes a co-solvent, a surfactant having a hydrophilic lipophilic balance (HLB) value that is less than 10, a carbon black pigment, a polymeric dispersant, and a balance of water. The cosolvent is present in an amount ranging from about 15 wt % to about 30 wt % of a total wt % of the coalescing agent. The surfactant is present in an amount ranging from about 0.5 wt % to about 1.4 wt % of the total wt % of the coalescing agent. The carbon black pigment is present in an amount ranging from about 3.0 wt % to about 6.0 wt % of the total wt % of the coalescing agent. The polymeric dispersant has a weight average molecular weight ranging from about 12,000 to about 20,000.

Claims

1. A coalescing agent for three-dimensional (3D) printing a polymeric build material, the coalescing agent comprising:

a co-solvent present in an amount ranging from about 21.5 wt % to about 30 wt % of a total wt % of the coalescing agent;

a surfactant present in an amount ranging from about 0.5 wt % to about 1.4 wt % of the total wt % of the coalescing agent, the surfactant having a hydrophilic lipophilic balance (HLB) value that is less than 10;

a carbon black pigment present in an amount ranging from about 3.0 wt % to about 6.0 wt % of the total wt % of the coalescing agent;

a polymeric dispersant having a weight average molecular weight ranging from about 12,000 to about 20,000; and

a balance of water.

2. The coalescing agent as defined in claim 1, further comprising a chelator present in an amount ranging from about 0.03 wt % to about 0.10 wt % of the total wt % of the coalescing agent.

3. The coalescing agent as defined in claim 1 wherein the polymeric dispersant is selected from the group consisting of a styrene acrylate and a polyurethane.

4. The coalescing agent as defined in claim 1 wherein the co-solvent has a boiling point of less than 300°

C.

5. The coalescing agent as defined in claim 4 wherein the co-solvent is selected from the group consisting of 2-Pyrrolidinone, 1,5-Pentanediol, Triethylene glycol, Tetraethylene glycol, 2-methyl-1,3-propanediol, 1,6-Hexanedol,Tripropylene glycol methyl ether, and combinations thereof, and wherein the coalescing agent excludes other co-solvents.

6. The coalescing agent as defined in claim 1 wherein the surfactant is a self-emulsifiable surfactant based on acetylenic diol chemistry or includes a combination of a fluorosurfactant and a self-emulsifiable surfactant based on acetylenic diol chemistry.

7. The coalescing agent as defined in claim 1, further comprising an anti-kogation agent including a combination of a polyacrylic acid polymer and Oleth-3 Phosphate, and wherein the combination is present in an amount ranging from greater than 0.20 wt % to about 0.62 wt % of the total wt % of the coalescing agent.

16. The coalescing agent as defined in claim 1 wherein the co-solvent is present in an amount of about 25 wt % based on the total wt % of the coalescing agent.

17. The coalescing agent as defined in claim 1 wherein the coalescing agent has a 10-ms dynamic surface tension of 26 dynes/cm.

8. A coalescing agent for three-dimensional (3D) printing a polymeric build material, the coalescing agent consisting of:

a co-solvent present in an amount ranging from about 21.5 wt % to about 30 wt % of a total wt % of the coalescing agent;

a surfactant present in an amount ranging from about 0.5 wt % to about 1.4 wt % of the total wt % of the coalescing agent, the surfactant having a hydrophilic lipophilic balance (HLB) value that is less than 10;

an anti-kogation agent present in an amount ranging from greater than 0.20 wt % to about 0.62 wt % of the total wt % of the coalescing agent;

a carbon black pigment present in an amount ranging from about 3.0 wt % to about 6.0 wt % of the total wt % of the coalescing agent;

a polymeric dispersant having a weight average molecular weight ranging from about 12,000 to about 20,000;

a chelator present in an amount ranging from about 0.03 wt % to about 0.10 wt % of the total wt % of the coalescing agent;

optionally a biocide; and

a balance of water.

9. The coalescing agent as defined in claim 8 wherein the biocide is present in the coalescing agent, and wherein the biocide is present in an amount ranging from about 0.30 wt % to about 0.40 wt % of the total wt % of the coalescing agent.

18. The coalescing agent as defined in claim 8 wherein the coalescing agent has a 10-ms dynamic surface tension of 26 dynes/cm.

10. A layer of a 3D printed object, comprising:

a build material; and

a coalescing agent applied on a surface of at least some of the build material, the coalescing agent including;

a co-solvent present in an amount ranging from about 21.5 wt % to about 30 wt % of a total wt % of the coalescing agent;

a surfactant present in an amount ranging from about 0.5 wt % to about 1.4 wt % of the total wt % of the coalescing agent, the surfactant having a hydrophilic lipophilic balance (HLB) value that is less than 10;

a carbon black pigment present in an amount ranging from about 3.0 wt % to about 6.0 wt % of the total wt % of the coalescing agent;

a polymeric dispersant having a weight average molecular weight ranging from about 12,000 to about 20,000; and

a balance of water.

11. The layer as defined in claim 10 wherein the build material is a polymer selected from the group consisting of polyamide, polyethylene, polyethylene terephthalate (PET), polystyrene, polyacetal, polypropylene, polycarbonate, polyester, polyurethanes, and blends thereof.

12. The layer as defined in claim 10 wherein the coalescing agent further includes:

an anti-kogation agent present in an amount ranging from greater than 0.20 wt % to about 0.62 wt % of the total wt % of the coalescing agent;

a chelator present in an amount ranging from about 0.03 wt % to about 0.10 wt % of the total wt % of the coalescing agent; and

a biocide present in an amount ranging from about 0.30 wt % to about 0.40 wt % of the total wt % of the coalescing agent.

13. The layer as defined in claim 10 wherein the co-solvent has a boiling point of less than 300°

C., and wherein the co-solvent is selected from the group consisting of 2-Pyrrolidinone, 1,5-Pentanediol, Triethylene glycol, Tetraethylene glycol, 2-methyl-1,3-propanediol, 1,6-Hexanedol, and Tripropylene glycol methyl ether.

14. The layer as defined in claim 10 wherein the surfactant is a self-emulsifiable surfactant comprising an acetylenic diol or includes a combination of a fluorosurfactant and a self-emulsifiable surfactant comprising an acetylenic diol.

15. The layer as defined in claim 10 wherein the polymeric dispersant is selected from the group consisting of styrene acrylate and polyurethane.