Bag or bundle-type packaging with no plastic elements and high protection from moisture and water

Abstract

The present utility model refers to a bag or a bundle-type packaging suitable to contain cement or other similar material, consisting of at least one sheet of paper wherein the external sides of said sheets are coated with at least one layer of hydrophobic paint.This paint transfers water-repellent characteristics to the paper; in this way, both the transmission of moisture/water vapor (WVTR) and the absorption of water (COBB) are significantly reduced.In fact, thanks to at least one layer of paint applied externally to the sheets of paper that make up the bag, the water is not retained by the paper, but slips away due to the high surface tension present on the treated paper.The barrier effect is thus increased compared to that obtainable from standard bags known in the art, thus guaranteeing the product contained inside the bag a high protection from humidity, even in the absence of intermediate polythene sheets in the manufacture of the bag and, consequently, improving the shelf life of the product contained inside the bag.The bag achieves these results even though it has no intermediate plastic layers.

1 . Bag or bundle-type packaging comprising at least two sheets of paper overlapped on each other, wherein the external sides of said sheets are coated with at least one layer of hydrophobic paint, characterized in that said paint is distributed on each of said sheets of paper with a weight in the range of about 4 gr/m 2  to about 9 gr/m 2 . 
     
     
         2 . Bag or bundle-type packaging according to  claim 1 , comprising at least three sheets of paper overlapped on each other. 
     
     
         3 . Bag or bundle-type packaging according to  claim 1 , wherein said hydrophobic paint is a water-based. 
     
     
         4 . Bag or bundle-type packaging according to  claim 1 , comprising a main lateral external surface and at least one lower bottom secured to said main external surface, wherein each of said main lateral external surface and said lower bottom comprises at least two of said sheets of paper overlapped on each other coated with at least one layer of hydrophobic paint. 
     
     
         5 . Bag or bundle-type packaging according to  claim 1 , further comprising an upper bottom secured to said main external surface, wherein said upper bottom also comprises at least two of said sheets of paper overlapped on each other with at least one layer of hydrophobic paint. 
     
     
         6 . Bag or bundle-type packaging according to  claim 1 , wherein the internal sides of said at least two sheets are glued to each other at the upper end and the lower end of said sheets so as to create a sort of tube inside the bag. 
     
     
         7 . Bag or bundle-type packaging according to  claim 6  wherein the internal sides of said at least two sheets are glued to each other in points arranged at said upper and lower ends. 
     
     
         8 . Bag or packaging according to  claim 6 , wherein the internal sides of said at least two sheets are glued to each other by means of starch glue or vinyl glue. 
     
     
         9 . Bag or bundle-type packaging according to  claim 1 , wherein said bag further comprises closure systems along a longitudinal line of the external lateral surface of the bag that extends substantially from said lower bottom to said upper bottom, wherein said systems of closure include escape routes to ensure the escape of air from the inside of the bag. 
     
     
         10 . Bag or bundle-type packaging comprising a single sheet of paper, optionally coupled with at least one other sheet of paper or plastic material, wherein the outer side of said bag or bundle-type packaging is coated with at least one layer of hydrophobic paint having a weight in the range from about 4 gr/m 2  to about 9 gr/m 2 .