Visible light curing systems, methods for reducing health risks to individuals exposed to systems designed to cure curable compositions by exposure to radiation, methods for bonding substrates and visible light curing compositions

1. A visible light curable composition comprising:

A urethane component, comprising one or more of

A station wherein the radiation curable composition is dispensed onto at least one substrate, and

A station wherein the at least substrate to which has been applied the radiation curable composition is exposed solely to radiation in the visible range of the electromagnetic spectrum generated from the solely visible radiation-generating source,

wherein health risks selected from the group consisting of erythema, photokeratitis, and combinations thereof of an individual using the system and being exposed to an environment in which radiation curable compositions are being cured by exposure to radiation in the electromagnetic spectrum are reduced,

wherein the radiation curable composition comprises

A urethane component, comprising one or more of

An aliphatic urethane triacrylate comprising the combination of greater than 50% of a urethane acrylate and less than 50% of tripropylene glycol diacrylate,

An aliphatic polyether urethane oligomer comprising a multifunctional terminally unsaturated urethane prepared from one or more hydroxyl-functional vinyl ethers selected from the group consisting of ethylene glycol monovinyl

An aliphatic urethane triacrylate comprising the combination of greater than 50% of a urethane acrylate and less than 50% of tripropylene glycol diacrylate,

An aliphatic polyether urethane oligomer comprising a multifunctional terminally unsaturated urethane oligomer comprising the reaction product of (a) a terminally unsaturated isocyanate containing polyurethane oligomer with (b) an alkoxylated polyhydric alcohol,

A trifunctional aliphatic urethane acrylate oligomer,

A reactive diluent comprising the combination of two or more of hexane diol di(meth)acrylate present in an amount of about 5 to about 15 weight percent, dimethyl acrylamide present in an amount of about 20 to about 25 weight percent, ethoxyethoxyethyl acrylate and tetrahydrafurfuryl acrylate,

A photoinitiator triggered upon exposure to radiation in the visible range of the electromagnetic spectrum, and

A photoinitiator synergist, wherein the multifunctional terminally unsaturated urethane oligomer is prepared from one or more hydroxyl-functional vinyl ethers selected from the group consisting of ethylene glycol monovinyl ether and cyclohexane dimethanol monovinyl ether.

2. The composition of claim 1 , wherein the cured radiation curable composition demonstrates a shear bond strength of greater than 1,000 psi when adhering together two substrates in a bond area of about ½ in 2 , wherein at least one substrate is constructed from polycarbonate.

3. The composition of claim 1 , wherein the aliphatic urethane triacrylate, aliphatic polyether urethane oligomer or trifunctional aliphatic urethane acrylate oligomer is made from a polyol selected from the group consisting of 2,2-(4,4′-dihydroxydiphenyl)-propane, 4,4′-iso-propylidenedicyclohexanol, ethoxylated bisphenol-A, propoxylated bisphenol-A, 2,2-(4,4′-dihydroxydiphenyl)-butane, 3,3-(4,4′-dihydroxydiphenyl)-pentane, α,α′-(4,4′-dihydroxydiphenyl) -p-diisopropylbenzene, 1,3-cyclohexane diol, 1,4-cyclohexane diol, 1,4-cyclohexanedimethanol, bicyclic and tricyclic diols, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, hydroquinone, resorcinol, 2,2-(4,4′-dihydroxyphenyl)-sulfone, 4,4′-oxydiphenol and 4,8-bis(2-hydroxymethyl)tricyclo[5.2.1.0 2,6 ] decane.

4. The composition of claim 1 , wherein the photosynergist is a member selected from the group consisting of N-methyl-diethanol amine, triethanolamine 2-(butoxy)ethyl-4-dimethyaminobenzoate and acrylated amines.

5. The composition of claim 1 , further comprising a silane coupling agent.

6. The composition of claim 1 , further comprising a fluorescent agent.

7. A method for reducing the health risks of an individual exposed to an environment in which radiation curable compositions are being cured by exposure to radiation in the electromagnetic spectrum, said method comprising the steps of:

Providing a radiation curable composition, in accordance with claim 1 , capable of being cured by exposure to radiation solely in the visible range of the electromagnetic spectrum,

Providing two or more substrates, at least one of which is substantially transmissive to radiation in the visible range of the electromagnetic spectrum,

Applying said radiation curable composition to said at least one substrate, and

Exposing said radiation curable composition applied to at least one substrate to a source which generate soley said radiation in the visible range of the electromagnetic spectrum for a period of time of 60 seconds or less so as to cure said radiation curable composition,

wherein the health risks are selected from the group consisting of erythema, photokeratitis, and combinations thereof.

8. A method of bonding two or more substrates, at least one of which is substantially transmissive to radiation in the visible range of the electromagnetic spectrum, said method comprising the steps of:

Providing a radiation curable composition in accordance with claim 1 , capable of being cured by exposure to radiation solely in the visible range of the electromagnetic spectrum,

Providing two or more substrates, at least one of which is substantially transmissive to radiation in the visible range of the electromagnetic spectrum,

Applying said radiation curable composition to said at least one substrate, and

Exposing said radiation curable composition applied to at least one substrate to a source to generate solely said radiation in the visible range of the electromagnetic spectrum for a period of time of 60 seconds or less so as to cure said radiation curable composition.

9. The method of claim 8 , wherein the cured radiation curable composition demonstrates a shear bond strength of greater than 1,000 psi when adhering together two substrates in a bond area of about ½ in 2 , wherein at least one substrate is constructed from polycarbonate.

10. The method of claim 8 , wherein the cured radiation curable composition demonstrates substantially no coloring.

11. A system for bonding together two or more substrates, at least one of which being constructed from a material that is substantially transmissive to radiation in the visible range of the electromagnetic spectrum, using a radiation curable composition in accordance with cliam 1 which is capable of curing upon exposure to radiation in the visible range of the electromagnetic spectrum, said system comprising:

A source for generating radiation solely in the visible range of the electromagnetic spectrum,

A source for dispensing radiation curable composition,

A station wherein radiation curable composition is dispensed onto at least one substrate, and

A station wherein the at least substrate to which has been applied radiation curable composition is exposed solely to radiation in the visible range of the electromagnetic spectrum generated from the solely visible radiation-generating source,

wherein health risks selected from the group consisting of erythema, photokeratitis, and combinations thereof of an individual using the system and being exposed to an enivronment in which radiation curable compositions are being cured by exposure to radiation in the electromatic spectrum are reduced.

12. A system for bonding together two or more substrates, at least one of which being constructed from a material that is substantially transmissive to radiation in the visible range of the electromagnetic spectrum, using a radiation curable composition which is capable of curing upon exposure to radiation in the visible range of the electromagnetic spectrum, said system comprising:

A source for generating radiation solely in the visible range of the electromagnetic spectrum,

A source for dispensing the radiation curable composition,

A station wherein the radiation curable composition is dispensed onto at least one substrate, and

A station wherein the at least substrate to which has been applied the radiation curable composition is exposed solely to radiation in the visible range of the electromagnetic spectrum generated from the solely visible radiation-generating source,

wherein health risks selected from the group consisting of erythema, photokeratitis, and combinations thereof of an individual using the system and being exposed to an environment in which radiation curable compositions are being cured by exposure to radiation in the electromagnetic spectrum are reduced,

wherein the radiation curable composition comprises

A urethane component, comprising one or more of

An aliphatic urethane triacrylate comprising the combination of greater than 50% of a urethane acrylate and less than 50% of tripropylene glycol diacrylate,

An aliphatic polyether urethane oligomer comprising a multifunctional terminally unsaturated urethane oligomer prepared from one or more hydroxyl-functional vinyl ethers selected from the group consisting of ethylene glycol monovinyl ether and cyclohexane dimethanol monovinyl ether, and

A trifunctional aliphatic urethane acrylate oligomer,

A reactive diluent comprising the combination of two or more of hexane diol di(meth)acrylate, dimethyl acrylamide, ethoxyethoxyethyl acrylate and tetrahydrafurfuryl acrylate,

A photoinitiator triggered upon exposure to radiation in the visible range of the electromagnetic spectrum, and

A photoinitiator synergist, wherein the radiation generating source is a mercury or metal halide based lamp, equipped to eliminate radiation below 400 nm.

13. A system for bonding together two or more substrates, at least one of which being constructed from a material that is substantially transmissive to radiation in the visible range of the electromagnetic spectrum, using a radiation curable composition which is capable of curing upon exposure to radiation in the visible range of the electromagnetic spectrum, said system comprising:

A source for generating radiation solely in the visible range of the electromagnetic spectrum,

A source for dispensing the radiation curable composition,

A station wherein the radiation curable composition is dispensed onto at least one substrate, and

A station wherein the at least substrate to which has been applied the radiation curable composition is exposed solely to radiation in the visible range of the electromagnetic spectrum generated from the solely visible radiation-generating source,

wherein health risks selected from the group consisting of erythema, photokeratitis, and combinations thereof of an individual using the system and being exposed to an environment in which radiation curable compositions are being cured by exposure to radiation in the electromagnetic spectrum are reduced,

wherein the radiation curable composition comprises

A urethane component, comprising one or more of

An aliphatic urethane triacrylate comprising the combination of greater than 50% of a urethane acrylate and less than 50% of tripropylene glycol diacrylate,

An aliphatic polyether urethane oligomer comprising a multifunctional terminally unsaturated urethane prepared from one or more hydroxyl-functional vinyl ethers selected from the group consisting of ethylene glycol monovinyl ether and cyclohexane dimethanol monovinyl ether, and

A trifunctional aliphatic urethane acrylate oligomer,

A reactive diluent comprising the combination of two or more of hexane diol di(meth)acrylate, dimethyl acrylamide, ethoxyethoxyethyl acrylate and tetrahydrafurfuryl acrylate,

A photoinitiator triggered upon exposure to radiation in the visible range of the electromagnetic spectrum, and

A photoinitiator synergist, wherein the radiation generating source is a LED that emits radiation above 400 nm.

14. A system for bonding together two or more substrates, at least one of which being constructed from a material that is substantially transmissive to radiation in the visible range of the electromagnetic spectrum, using a radiation curable composition which is capable of curing upon exposure to radiation in the visible range of the electromagnetic spectrum, said system comprising:

A source for generating radiation solely in the visible range of the electromagnetic spectrum,

A source for dispensing the radiation curable composition, ether and cyclohexane dimethanol monovinyl ether, and

A trifunctional aliphatic urethane acrylate oligomer,

A reactive diluent comprising the combination of two or more of hexane diol di(meth)acrylate, dimethyl acrylamide, ethoxyethoxyethyl acrylate and tetrahydrafurfuryl acrylate,

A photoinitiator triggered upon exposure to radiation in the visible range of the electromagnetic spectrum, and

A photoinitiator synergist, wherein the radiation generating source is an OLED that emits radiation above 400 nm.