LIQUID SPRAY FORMULATION
The present invention relates to a liquid formulation for spraying on a face mask, the formulation being an aqueous solution having a pH in a range between 2.5 and 4 and comprising an organic acid selected from a list consisting of citric acid, malic acid, lactic acid and tartaric acids, a film forming polymer, and an anionic surfactant. Other aspects of the invention are the use of such a liquid formulation to spray it on a face mask, and a method of forming a film on a face mask.
1 - 23 . (canceled)
24 . A liquid formulation for spraying on a face mask comprising:
a. an organic acid selected from a group consisting of citric acid, malic acid, lactic acid and tartaric acids;
b. a film forming polymer; and
c. an anionic surfactant,
wherein the liquid formulation is an aqueous solution having a pH in a range between 2.5 and 4.
25 . The liquid formulation according to claim 24 , wherein the pH of the liquid formulation is between 2.5 and 3.5.
26 . The liquid formulation according to claim 24 , wherein the organic acid is citric acid.
27 . The liquid formulation according to claim 26 , wherein the citric acid is present in a concentration of 5% to 20% (w/v).
28 . The liquid formulation according to claim 24 , further comprising a base forming a buffer system with the organic acid.
29 . The liquid formulation according to claim 24 , wherein the film forming polymer is a hydrocolloid.
30 . The liquid formulation according to claim 29 , wherein the hydrocolloid is selected from a group consisting of Polyvinylpyrrolidone (PVP), Polyvinyl alcohol (PVA), and Hydroxypropyl methylcellulose (HPMC).
31 . The liquid formulation according to claim 24 , wherein the film forming polymer is Polyvinylpyrrolidone (PVP).
32 . The liquid formulation according to claim 24 , wherein the film forming polymer is present in an amount of 1% to 4% (w/v).
33 . The liquid formulation according to claim 24 , wherein the anionic surfactant is selected from a group consisting of sodium stearate, sodium cocosulfate, sodium laureth sulphate (SLES), ammonium lauryl sulphate, sodium myreth sulphate, and sodium lauryl sulphate (SLS).
34 . The liquid formulation according to claim 24 , wherein the anionic surfactant is sodium lauryl sulphate (SLS).
35 . The liquid formulation according to claim 24 , wherein the anionic surfactant is present in an amount of 0.1% to 0.6%.
36 . The liquid formulation according to claim 24 , wherein the liquid formulation has a viscosity below 5 mm 2 /s.
37 . The liquid formulation according to claim 24 , wherein the liquid formulation further comprises edetate disodium (EDTA) in an amount between 0.1 and 0.2% (w/v).
38 . The liquid formulation according to claim 24 , wherein the liquid formulation is essentially free of an alcohol, including ethanol and/or isopropyl alcohol.
39 . A metered-dose pump spray product comprising a liquid formulation according to claim 24 .
40 . Use of a liquid formulation according to claim 24 to spray on a face mask.
41 . Use of a liquid formulation according to claim 40 , wherein the face mask is a surgical mask, a FFP2 mask, or a cotton mask with at least 3 layers.
42 . A method of forming a film on a mask comprising the steps of spraying a liquid formulation according to claim 24 on a face mask.
43 . A method according to claim 42 , wherein the film forming polymer forms a hydrated polymer matrix film, with the organic acid being present in an amount of around 0.4 to 1.5 mg/cm 2 on a face mask surface.
44 . A face mask comprising a film layer formed by spraying with a liquid formulation according to claim 24 , wherein the organic acid is present in an amount of around 0.4 to 0.9 mg/cm 2 on a face mask surface.