Thermally cross-linkable photo-hydrolyzable inkjet printable polymers for microfluidic channels

Patent metadata

Field	Value
Publication number	US-9623605-B2
Application number	US-201213611135-A
Country	US
Kind code	B2
Filing date	Sep 12, 2012
Priority date	Sep 12, 2012
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

Thermally cross-linkable photo-hydrolyzable inkjet printable polymers are used to print microfluidic channels layer-by-layer on a substrate. In one embodiment, for each layer, an inkjet head deposits droplets of a mixture of hydrophobic polymer and cross-linking agent in a pattern lying outside a two-dimensional layout of the channels, and another inkjet head deposits droplets of a mixture of poly(tetrahydropyranyl methacrylate) PTHPMA (or another hydrophobic polymer which hydrolyzes to form a hydrophilic material), cross-linking agent, and a photoacid generator (PAG) in a pattern lying inside the two-dimensional layout of the channels. After all layers are printed, flood exposure of the entire substrate to UV radiation releases acid from the PAG which hydrolyzes PTHPMA to form hydrophilic poly(methacrylic acid) PMAA, thereby rendering the PTHPMA regions hydrophilic. The layers of these now-hydrophilic patterned regions together define the microfluidic channels. The cross-linking agent (e.g., triallyl isocyanurate TAIC) forms covalent cross-links between the two polymer phases.

First claim

What is claimed is:

1. A composition contained in a reservoir of an inkjet cartridge for fabricating microfluidic channels, consisting of:
a second mixture in the reservoir of the inkjet cartridge for supply to a second inkjet head, the second mixture consisting of poly(tetrahydropyranyl methacrylate) (PTHPMA), a cross-linking agent, and a photoacid generator, wherein the second mixture contains less than 2 wt % of the photoacid generator and 2 to 5 wt % of the cross-linking agent;
wherein the cross-linking agent includes a multi-functional thermally cross-linkable monomer that is capable of copolymerizing with both a hydrophobic polymer contained in a first mixture and the PTHPMA to form covalent cross-links between the hydrophobic polymer and the PTHPMA when the first mixture and the second mixture are placed in contact with one another upon being deposited on a substrate by a first inkjet head and the second inkjet head, respectively, and exposed to heat.

2. The composition as recited in claim 1 , wherein the cross-linking agent is triallyl isocyanurate (TAIC), and wherein the hydrophobic polymer is selected from a group consisting of poly(tetrahydropyranyl methacrylate) (PTHPMA), poly(methyl methacrylate) (PMMA), and combinations thereof.

3. The composition as recited in claim 1 , wherein the cross-linking agent is selected from a group consisting of triallyl isocyanurate (TAIC), diallyl itaconate, allyl methacrylate, allyl pentaerythritol, N,N′-methylenebis(acrylamide), trimethylolpropane trimethacrylate, 1,3-butylenegylycol dimethacrylate, polyethyleneglycol diacrylate, polyethyleneglycol dimethacrylate, ethyleneglycol dimethacrylate, diethyleneglycol divinyl ether, tetraethyleneglycol diacrylate, and combinations thereof, and wherein the hydrophobic polymer is selected from a group consisting of polystyrene, polyisobutylene, and combinations thereof.

4. A composition contained in a reservoir of an inkjet cartridge for fabricating microfluidic channels, consisting of:
a second mixture in the reservoir of the inkjet cartridge for supply to a second inkjet head, the second mixture consisting of at least one hydrophobic polymer, at least one cross-linking agent, and at least one photoacid generator, wherein the second mixture contains less than 2 wt % of the at least one photoacid generator and 2 to 5 wt % of the at least one cross-linking agent, and wherein each of the at least one hydrophobic polymer contains a hydrolyzable group and is capable of hydrolyzing to form a hydrophilic material when exposed to UV light;
wherein each of the at least one cross-linking agent includes a multi-functional thermally cross-linkable monomer that is capable of copolymerizing with a hydrophobic polymer contained in a first mixture and the at least one hydrophobic polymer to form covalent cross-links between the hydrophobic polymer and the at least one hydrophobic polymer when the first mixture and the second mixture are placed in contact with one another upon being deposited on a substrate by a first inkjet head and the second inkjet head, respectively, and exposed to heat.

5. The composition as recited in claim 4 , wherein the at least one hydrophobic polymer is selected from a group consisting of poly(tetrahydropyranyl methacrylate) (PTHPMA), poly(methyl methacrylate) (PMMA), and combinations thereof.

6. The composition as recited in claim 5 , wherein the at least one cross-linking agent is selected from a group consisting of triallyl isocyanurate (TAIC), diallyl itaconate, allyl methacrylate, allyl pentaerythritol, N,N′-methylenebis(acrylamide), trimethylolpropane trimethacrylate, 1,3-butylenegylycol dimethacrylate, polyethyleneglycol diacrylate, polyethyleneglycol dimethacrylate, ethyleneglycol dimethacrylate, diethyleneglycol divinyl ether, tetraethyleneglycol diacrylate, and combinations thereof.

7. The composition as recited in claim 5 , wherein the at least one photoacid generator is selected from a group consisting of triphenylsulfonium hexafluorotriflate, (4-octyloxy-phenyl) phenyliodonium hexafluoroantimonate, and combinations thereof.

8. A composition, consisting of:
a mixture consisting of at least one hydrophobic polymer, at least one cross-linking agent, and at least one photoacid generator, wherein the mixture contains less than 2 wt % of the at least one photoacid generator and 2 to 5 wt % of the at least one cross-linking agent,
wherein the at least one hydrophobic polymer is selected from a group consisting of poly(tetrahydropyranyl methacrylate) (PTHPMA), poly(methyl methacrylate) (PMMA), and combinations thereof,
wherein the at least one cross-linking agent is selected from a group consisting of triallyl isocyanurate (TAIC), diallyl itaconate, allyl methacrylate, allyl pentaerythritol, N,N′-methylenebis(acrylamide), trimethylolpropane trimethacrylate, 1,3-butylenegylycol dimethacrylate, polyethyleneglycol diacrylate, polyethyleneglycol dimethacrylate, ethyleneglycol dimethacrylate, diethyleneglycol divinyl ether, tetraethyleneglycol diacrylate, and combinations thereof, and
wherein the at least one photoacid generator is selected from a group consisting of triphenylsulfonium hexafluorotriflate, (4-octyloxy-phenyl) phenyliodonium hexafluoroantimonate, and combinations thereof.

Assignees

• Boday Dylan J
• Kuczynski Joseph
• Meyer Iii Robert E
• IBM

Inventors

• Boday Dylan J
• Kuczynski Joseph
• Meyer Iii Robert E

Classifications

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title

• C09D11/106 Primary

  containing macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09D11/30

  Inkjet printing inks · CPC title

• Y10T428/24802

  Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.] · CPC title

• B29C67/0059 Primary

  Operations & Transport · mapped topic