A composition comprising:
- about 40 to about 60 weight % of at least one kind of ethoxylated difunctional bisphenol A dimethacrylate;
- about 5 to about 20 weight % of at least one kind of multifunctional methacrylate;
- about 20 to about 45 weight % of at least one kind of urethane dimethacrylate;
- about 0 to about 15 weight % of at least one kind of silica particles having methacrylate functionalization layers and having an average particle size of less than about 200 nm;
- about 0.2 to about 5.0 weight % of at least one kind of ultraviolet/visible (UV/Vis) light-photo-polymerization initiator;
- at least one colorant;
- and
- at least one stabilizer,
- wherein viscosity of a liquid state mixture, including the at least one kind of ethoxylated difunctional bisphenol A dimethacrylate, the at least one kind of multifunctional methacrylate, the at least one kind of urethane dimethacrylate, the at least one kind of silica particles, the at least one kind of UV/Vis light-photo-polymerization initiator, the at least one colorant, and the at least one stabilizer, is from 1000 to 5200 centipoise (cps) at room temperature or 25° C. and from 50 to 500 cps at 70° C.,
- wherein the viscosity is adjusted to be within a range from 1000 to 5200 centipoise (cps) at room temperature or 25° C. and from 50 to 500 cps at 70° C. by controlling a ratio of the at least one kind of ethoxylated difunctional bisphenol A dimethacrylate, the at least one kind of multifunctional methacrylate, the at least one kind of urethane dimethacrylate, the at least one kind of silica particles, the at least one kind of UV/Vis light-photo-polymerization initiator, the at least one colorant, and the at least one stabilizer in the mixture, and
- wherein weight % of the at least one kind of ethoxylated difunctional bisphenol A dimethacrylate is greater than weight % of the at least one kind of urethane dimethacrylate in the composition including more than 0 weight % of the at least one kind of silica particles.