Bismaleimide-based solution for inkjet ink for three dimensional printing

Abstract

A polyimidc-based solution for inkjet printing includes an α,ω-Bismaleimide(BMI) terminated oligomer, wherein said α,ω-Bismaleimide terminated oligomer is delined by formula (I), wherein R represents an aliphatic, an aromatic or mixed aliphatic and aromatic groups. ##STR00001##

Claims

1. A curable liquid composition for inkjet 3D printing comprising: (A) Bismaleimide (BMI) α,{acute over (ω)}-terminated compound defined by the general formula (1): ##STR00005## where “-R-” is a bivalent spacer that include hydrocarbon group comprising alkylene-, alkylidene-, arylene-, aralkylene-, alkarylene- groups, and groups, containing heteroatoms comprising Si, O, S, N and P. (B) Organic diluent or solvent (C) Reactive additives, wherein said reactive additives (C) comprise curing initiators, reagents and surfactants, and wherein said α,{acute over (ω)}-BMI-compound (A) is used as a stable suspension of a micronized powder in said organic diluent (B) in combination with said reactive additives and surfactants (C).

2. The composition according to claim 1, wherein said α,{acute over (ω)}-BMI-compounds (A) are used as a low viscous solution in a suitable Organic solvent (B) in combination with said reactive additives (C).

3. The composition according to claim 1, wherein said α,{acute over (ω)}-BMI-compounds (A) undergoes quick thermal- and (or) photo-initiating curing during inkjet 3D printing process (1-20 sec. per layer) in the presence of the Reactive additives (C).

4. The composition according to claim 1, wherein said solvents (B) having a boiling temperature below 190° C. and an evaporation rate lower than 1.

5. The composition according to claim 1, wherein said solvents (B) comprises Alcohols, Mono-alkyl ethers, comprising 2-Ethoxyethanol or 2-Butoxyethanol and Alkyl carboxylates comprising n-Alkyl Acetates and n-Alkyl Propionate with Alkyl=C.sub.nH.sub.2n+1, n=4-8.

6. The composition according to claim 1, wherein said Bismaleimide (BMI) α,{acute over (ω)}-terminated compound is mixed with a solvent to form a BMI-based solution that has a viscosity of 7-88 mPa.s at 40-65° C.

7. The composition according to claim 1, wherein said α,{acute over (ω)}-BMI-compound (A) has a molecular weight from 250 to 10,000 Dalton and can be represented as an individual compound or as a α,{acute over (ω)}-Bismaleimide-terminated oligomer.

8. A curable liquid composition for inkjet 3D printing comprising: (A) Bismaleimide (BMI) α,{acute over (ω)}-terminated compound defined by the general formula (1): ##STR00006## where “-R-” is a bivalent spacer that include hydrocarbon group comrising alkylene-, alkylidene-, arylene-, aralkylene-, alkarylene- groups, and groups, containing heteroatoms comprising Si, O, S, N and P. (B) Organic diluent or solvent (C) Reactive additives, wherein said reactive additives (C) comprise curing initiators, reagents and surfactants, and wherein said α,{acute over (ω)}-BMI-compound (A) is used in combination with said reactive additives, wherein one of said reactive additives comprises oligomeric polyamine containing reactive N-H bonds, that undergoes Michael addition reaction to said BMI-compound during the thermal curing process.

9. The composition according to claim 8, wherein said α,{acute over (ω)}-BMI-compound (A) is used as a low viscous solution in a suitable Organic solvent (B) in combination with Reactive additives (C).

10. The composition according to claim 8, wherein said α,{acute over (ω)}-BMI-compounds (A) undergoes quick thermal- or photo-initiating curing during inkjet 3D printing process in the presence of the Reactive additives (C).

11. A curable liquid composition for inkjet 3D printing comprising: (A) Bismaleimide (BMI) α,{acute over (ω)}-terminated compound defined by the general formula ##STR00007## where “-R-” is a bivalent spacer that include hydrocarbon group comprising alkylene-, alkylidene-, arylene-, aralkylene-, alkarylene- groups, and groups, containing heteroatoms comprising Si, O, S, N and P. (B) Organic diluent or solvent (C) Reactive additives, wherein said reactive additives (C) comprise curing initiators, reagents and surfactants, and wherein said α,{acute over (ω)}-BMI-compound (A) has a molecular weight 689 Dalton and can be used alone or in a mixture with other BMI-compounds.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

(1) In one embodiment, the solution development is based on a solution of reactive BMI oligomers dissolved in organic solvent (Route 1).

(2) The solution contains α,ω-Bismaleimide terminated oligomers with or without reactive additives.

(3) The α,ω-Bismaleimide compound is defined by a general formula (1):

(4) ##STR00003##

(5) wherein R represents an aliphatic, aromatic or a mixed aliphatic and aromatic groups.

(6) The reactive BMI containing oligomers include liquid or powder BMI resins and/or imide-extended BMI oligomers with the average molecular weight up to 10,000, preferably from 500 to 3000 Daltons.

(7) The reactive additives include oligomeric polyamines that undergo Michael addition reaction with α,ω-Bismaleimide terminated oligomers.

(8) Suitable organic solvents are characterized by a boiling temperature below 190° C. and low evaporation rate, lower than 1 (preferably lower than 0.3).

(9) The suitable solvents include alcohols, or esters of carboxylic acids defined by a general formula (2):

(10) ##STR00004##

(11) wherein R and R′ represent different alkyl groups, which are not related to those mentioned in formula (1).

(12) The oligomeric BMI component undergoes quick curing (1-20 seconds per layer), forming a three-dimensional network of a thermosetting polymer material.

(13) The curing can be done by a thermal treatment, UV irradiation, or both.

(14) Photo-curing can be done by UV sources, such as Xe lamp, mercury lamp, LED UV lamp, intense pulsed light (IPL), or UV laser, with intensity of up to 2000 J/cm.sup.2 in the UV-VIS spectral range.

(15) For enhancement of UV curing, photo-initiators can be added at 0.1-5 wt. %. The examples of photo-initiators are a-hydroxyketones, Bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide, or their combination.

(16) Thermal curing can be done by UV-VIS radiation or conduction, for example by using IR lamp, and/or heating of the printed surface by heating of the printing tray or the environment in the chamber.

(17) Thermal curing can be enhanced by addition of peroxide catalyst, such as dicumyl peroxide (added at 0.01-2 wt. %) or epoxy catalyst.

EXAMPLE

(18) BMI-based solutions were prepared by mixing BMI precursor in different solvents, such as butyl acetate, hexyl acetate, or ethyl caproate from Sigma Aldrich. Imide-extended or linear-chain extended BMI oligomers, such as BMI1400, BMI1500, BMI1700, BMI3000, or BMI689 from Design Molecules Inc. were used as Bismaleimide precursors. The homogeneous nature of the solutions was assisted by a vortex mixer, Velp. Scientifica, ZX classic at 3000 rpm for 1 min, and a sonicator, Kudus, SK221OHP at 53 kHz and 40° C. for 30 min. Solubility of the Irgacure 819 photoinitiator from BASF Dispersions & Pigments was achieved by heating the BMI-based solution in an oven up to 85° C. The viscosity of BMI-based solutions was measured by a viscometer (DV-I Prime, Brookfield) with thermoregulation by water circulation (Ministat 125, Huber). The examples of achieved viscosities at various tempeartures are shown in Table 1.

(19) TABLE-US-00001 TABLE 1 Viscosities of the BMI-based solutions Temperature Viscosity Solution composition (° C.) (mPa .Math. s) BMI3000 (30 wt. %) in n-Buthyl Acetate 40 11 50 9 60 7 BMI3000 (40 wt. %) in n-Buthyl Acetate 40 29 50 19 60 16 BMI3000 (40 wt. %) in Hexyl Acetate 40 88 60 21 65 14 BMI689 (60 wt. %) in Hexyl Acetate 40 15 60 9 65 7 BMI689 (80 wt. %) in Hexyl Acetate 40 65 60 24 65 19
The invention is not limited to these examples.