Low temperature snap cure material with suitable worklife
The present invention discloses a one part, snap curing, acrylic-based composition with long worklife at room temperature. The composition cures in less than 60 seconds at temperatures below 120° C. and provides a suitable worklife of 3 days at room temperature. The composition comprise of a radical initiator with a ten hour half life, 10 hr T 1/2 , equal to or less than 80° C., (meth)acrylate or vinylene-containing base oligomers and at least one additional (meth)acrylate monomer to dilute the base oligomers. Additional ingredients, such as non-reactive chemical compounds, thixotropic agents, pigments, and fillers may be added as desired. A further embodiment of the invention is a method of using the composition with an electronic device.
1 . Acrylic adhesive composition comprising:
(a) a radical initiator with ten-hour-half-life equal to or less than 80° C.;
(b) a vinylene-containing oligomer; and
(c) at least one diluent,
wherein the composition can snap cure at low temperature with at least 24 hour worklife at room temperature.
2 . The composition of claim 1 , wherein the radical initiator with ten-hour-half-life is selected from the group comprising diacryl peroxide, peroxydicarbonate, and peroxyester-type initiators.
3 . The composition of claim 1 , wherein the vinylene-containing oligomers is a urethane acrylate or epoxy acrylate.
4 . The composition of claim 1 , wherein the diluent is a (meth)acrylate monomer.
5 . The composition of claim 2 , wherein the radical initiator comprises in the range of about 0.1 wt % to 10 wt % of the total compound admixture.
6 . The composition of claim 5 , wherein the radical initiator comprises in the range of about 1 wt % to 4 wt % of the total compound admixture.
7 . The composition of claim 3 , wherein the vinylene-containing oligomers comprises in the range of about 1 wt % to 90 wt % of the total compound admixture.
8 . The composition of claim 7 , wherein the vinylene-containing oligomers comprises in the range of about 10 wt % to 60 wt % of the total compound admixture.
9 . The composition of claim 4 , wherein the diluent comprises in the range of about 0.1 wt % to 99 wt % of the total compound admixture.
10 . The composition of claim 9 , wherein the diluent comprises in the range of about 20 wt % to 70 wt % of the total compound admixture.
11 . The composition of claim 1 , further comprising one or more of the group comprising of non-reactive chemical.
12 . The composition of claim 11 , wherein the non-reactive chemical to enhance viscosity comprises in the range of about 0.01 wt % to 50 wt % of the total compound admixture.
13 . The composition of claim 1 , further comprising one or more of the group comprising of pigment.
14 . The composition of claim 13 , wherein the pigment comprises in the range of about 0.1 wt % to 10 wt % of the total compound admixture.
15 . The composition of claim 14 , wherein the pigment comprises in the range of about 0.1 wt % to 3 wt % of the total compound admixture.
16 . The composition of claim 1 , further comprising of fillers.
17 . The composition of claim 16 , wherein the filler is selected from the group comprising silver, nickel, gold, aluminum, copper, metal oxides, boron nitride, aluminum oxide, silver plated aluminum, silver plated glass, silver flakes, carbon black, graphite, boron nitride-coated particles, gold coated nickel, polymer coated fillers, silica, mica, talc, or hollow glass beads, zinc oxide, magnesium oxide, or mixtures thereof.
18 . The composition of claim 16 , wherein the filler comprises in the range of about 0.01 wt % to 99 wt % of the total compound admixture.
19 . The composition of claim 1 , wherein the adhesive is applied to electronic devices.
20 . The composition of claim 19 , wherein the adhesive is applied to the electronic device via stencil, screen-print, inkjet print, spin-coat, or syringe.