Low-tack, UV-cured pressure sensitive adhesive suitable for reclosable packages
UV-cured pressure sensitive adhesive including one or more UV-curable acrylic oligomers, one or more tack control components, and, optionally, an elastomeric material is described herein. The adhesive includes an adhesive component ratio of the various adhesive components effective to provide desired first peel adhesions and subsequent peel adhesions.
1. A UV-curable pressure sensitive adhesive comprising:
a UV-curable acrylic oligomer, a tack control component, and optionally at least one elastomeric material;
an adhesive component ratio (ACR) of the pressure sensitive adhesive defined by formula (A) where the weight percent of the UV-curable acrylic oligomer relative to the sum of the weight percents of the tack control component and the elastomeric material is about 0.5 to about 1.5
(
UV
-
curable
acrylic
oligomer
)
(
tack
control
component
+
elastomeric
material
)
;
(
A
)
the ACR effective so that a UV-cured pressure sensitive adhesive forms a first peel adhesion force between opposing strips of the UV-curable pressure sensitive adhesive of about 200 to about 900 grams per linear inch (gpli) and up to five subsequent peel adhesions between the opposing strips each about 30 to about 200 percent of the first peel adhesion and a first subsequent peel adhesion between the opposing strips after fouling with debris at least about 50 percent of the first peel adhesion;
a liquid mixture of the UV-curable acrylic oligomer, the tack control component, and the optional elastomeric material are compatible such that the liquid mixture remains a stable liquid that is homogeneous without phase separation for at least about 3 days at about 70 to about 75° F.;
wherein the UV-curable acrylic oligomer is an acrylic acid ester;
wherein the acrylic acid ester is an acrylic acid ester of a vegetable oil; and
wherein each of the opposing strips of the UV-cured pressure sensitive adhesive is applied to a substrate selected from the group consisting of paper, foil, and polymers wherein the polymers are selected from the group consisting of polyethylene, polybutylene, ethylene vinyl acetate, polyamides, polyvinyl chloride, ethylene vinyl alcohol, polyvinylidene chloride, polyvinyl alcohol, polystyrene, and combinations thereof.
2. The pressure sensitive adhesive of claim 1 , wherein the elastomeric material includes one of curable elastomeric acrylate esters or methacrylate esters selected from the group consisting of polybutadiene, saturated polybutadiene, and polyurethane.
3. A UV-curable pressure sensitive adhesive comprising:
a UV-curable acrylic oligomer, a tack control component, and optionally at least one elastomeric material;
an adhesive component ratio (ACR) of the pressure sensitive adhesive defined by formula (A) where the weight percent of the UV-curable acrylic oligomer relative to the sum of the weight percents of the tack control component and the elastomeric material is about 0.5 to about 1.5
(
UV
-
curable
acrylic
oligomer
)
(
tack
control
component
+
elastomeric
material
)
;
(
A
)
the ACR effective so that a UV-cured pressure sensitive adhesive forms a first peel adhesion force between opposing strips of the UV-curable pressure sensitive adhesive of about 200 to about 900 grams per linear inch (gpli) and up to five subsequent peel adhesions between the opposing strips each about 30 to about 200 percent of the first peel adhesion and a first subsequent peel adhesion between the opposing strips after fouling with debris at least about 50 percent of the first peel adhesion;
a liquid mixture of the UV-curable acrylic oligomer, the tack control component, and the optional elastomeric material are compatible such that the liquid mixture remains a stable liquid that is homogeneous without phase separation for at least about 3 days at about 70 to about 75° F.;
wherein the tack control component is an aliphatic urethane acrylate oligomer; and
wherein each of the opposing strips of the UV-cured pressure sensitive adhesive is applied to a substrate selected from the group consisting of paper, foil, and polymers wherein the polymers are selected from the group consisting of polyethylene, polybutylene, ethylene vinyl acetate, polyamides, polyvinyl chloride, ethylene vinyl alcohol, polyvinylidene chloride, polyvinyl alcohol, polystyrene, and combinations thereof.
4. The pressure sensitive adhesive of claim 1 , wherein the adhesive has a viscosity below about 50,000 cPs at about 70 to about 75° F.
5. The pressure sensitive adhesive of claim 4 , wherein the viscosity is about 5000 cPs or less at about 160° F.
6. The pressure sensitive adhesive of claim 1 , wherein the adhesive is cured with ultraviolet radiation supplied at an energy between about 100 and about 800 mJ/cm 2 so that the UV-cured pressure sensitive adhesive withstands at least 100 double rubs with methyl ethyl ketone.
7. The pressure sensitive adhesive of claim 1 , wherein the adhesive exhibits a rolling ball tack between about 4 to about 14 inches.
8. A UV-curable pressure sensitive adhesive comprising:
a UV-curable acrylic oligomer, a tack control component, and optionally at least one elastomeric material;
an adhesive component ratio (ACR) of the pressure sensitive adhesive defined by formula (A) where the weight percent of the UV-curable acrylic oligomer relative to the sum of the weight percents of the tack control component and the elastomeric material is about 0.5 to about 1.5
(
UV
-
curable
acrylic
oligomer
)
(
tack
control
component
+
elastomeric
material
)
;
(
A
)
the ACR effective so that a UV-cured pressure sensitive adhesive forms a first peel adhesion force between opposing strips of the UV-curable pressure sensitive adhesive of about 200 to about 900 grams per linear inch (gpli) and up to five subsequent peel adhesions between the opposing strips each about 30 to about 200 percent of the first peel adhesion and a first subsequent peel adhesion between the opposing strips after fouling with debris at least about 50 percent of the first peel adhesion;
a liquid mixture of the UV-curable acrylic oligomer, the tack control component, and the optional elastomeric material are compatible such that the liquid mixture remains a stable liquid that is homogeneous without phase separation for at least about 3 days at about 70 to about 75° F.;
wherein the UV-curable acrylic oligomer is an acrylic acid ester;
wherein the acrylic acid ester is an acrylic acid ester of a vegetable oil;
wherein the tack control component is an aliphatic urethane acrylate oligomer; and
wherein each of the opposing strips of the UV-cured pressure sensitive adhesive is applied to a substrate selected from the group consisting of paper, foil, and polymers wherein the polymers are selected from the group consisting of polyethylene, polybutylene, ethylene vinyl acetate, polyamides, polyvinyl chloride, ethylene vinyl alcohol, polyvinylidene chloride, polyvinyl alcohol, polystyrene, and combinations thereof.
9. The pressure sensitive adhesive of claim 8 , wherein the pressure sensitive adhesive includes about 1 to about 90 percent of the UV-curable acrylic oligomer, about 1 to about 65 percent of the tack control component, and about 5 to about 20 percent of the elastomeric material.
10. The pressure sensitive adhesive of claim 8 , wherein the elastomeric material includes one of curable elastomeric acrylate esters or methacrylate esters selected from the group consisting of polybutadiene, saturated polybutadiene, and polyurethane.
11. The pressure sensitive adhesive of claim 8 , wherein the adhesive has a viscosity below about 50,000 cPs at about 70 to about 75° F.
12. The pressure sensitive adhesive of claim 11 , wherein the viscosity is about 5000 cPs or less at about 160° F.
13. The pressure sensitive adhesive of claim 8 , wherein the adhesive is cured with ultraviolet radiation supplied at an energy between about 100 and about 800 mJ/cm 2 so that the UV-cured pressure sensitive adhesive withstands at least 100 double rubs with methyl ethyl ketone.
14. The pressure sensitive adhesive of claim 8 , wherein the adhesive exhibits a rolling ball tack between about 4 to about 14 inches.
15. The pressure sensitive adhesive of claim 1 , wherein the pressure sensitive adhesive includes about 1 to about 90 percent of the UV-curable acrylic oligomer, about 1 to about 65 percent of the tack control component, and about 5 to about 20 percent of the elastomeric material.