REDUCED PARTICLE AGGLOMERATION FOR PACKAGING FILMS
Water soluble particles can be incorporated into articles that are produced from a polymer based matrix with reduced appearance implications. Using a specific formulation including a water permeable polymer, water soluble particles and a surfactant, and a specific process for combining these components, agglomeration of the particles can be reduced. This is particularly useful for applications where the particles are incorporated into packaging films and extracted upon exposure to moist products.
1 . (canceled)
2 . A compounded resin comprising:
i) a high moisture transmission polymer;
ii) between 0.5 and 20 weight percent of a water soluble particle dispersed in the high moisture transmission polymer; and
iii) a surfactant.
3 . (canceled)
4 . A packaging film comprising a product contact layer comprising a compounded resin of claim 2 , wherein any agglomerations of water soluble particles in the packaging film have a size equal to or less than 1.0 mm 2 when measured using a size estimation chart as described in TAPPI test method T564.
5 . A packaging film of claim 4 , wherein any agglomerations of water soluble particles in the packaging film have a size equal to or less than 0.8 mm 2 .
6 . A packaging film comprising a product contact layer comprising:
i) a high moisture transmission polymer;
ii) at least 0.08 g/m 2 of a water soluble particle dispersed in the high moisture transmission polymer; and
iii) a surfactant;
wherein any agglomerations of water soluble particles in the packaging film have a size of equal to or less than 1.0 mm 2 when measured using a size estimation chart as described in TAPPI test method T564.
7 . A packaging film according to claim 4 , wherein the high moisture transmission polymer is ethylene vinyl acetate copolymer.
8 . A packaging film according to claim 7 , wherein the ethylene vinyl acetate copolymer has a vinyl acetate content of at least 18%.
9 . A packaging film according to claim 4 , wherein the water soluble particle is also water extractable.
10 . A packaging film according to claim 9 wherein the average cumulative amount of water soluble particle extracted from the product contact layer upon contact with water after 2 days at 23° C. and 1 atm is greater than 40% of the initial amount of particle present in the product contact layer.
11 . A packaging film according to claim 4 , wherein the water soluble particle is a salt of sorbic acid.
12 . A packaging film according to claim 4 , wherein the surfactant has an ethoxylation level of at least 10 moles per mole of surfactant.
13 . A packaging film according to claim 4 , wherein the surfactant has a hydrophilic lipophilic balance (HLB) of at least 10.
14 . A packaging film according to claim 4 , wherein the film has a haze level less than 35%.
15 . A packaging film according to claim 4 , wherein the film has a clarity level greater than 70%.
16 . A packaged product comprising:
a packaging film comprising a product contact layer comprising:
i) an ethylene vinyl acetate copolymer;
ii) a water soluble particle dispersed in the ethylene vinyl acetate copolymer; and
iii) a surfactant; and
a moist food product.
17 . A packaged product of claim 16 , wherein the water soluble particle is an antimicrobial agent.
18 . A packaged product of claim 16 , wherein the water soluble particle is an odor reducing agent.
19 . A packaged product of claim 16 , wherein the water soluble particle is potassium sorbate.
20 . A packaged product of claim 16 , wherein the moist food product is raw poultry.