Heat retaining swimming pool cover

Abstract

A plastic film for a heat-retaining swimming pool cover. The film is made of plastic material and has contained therein an infrared absorbent material. The amount of infrared absorbent material is insufficient to prevent some light from substantially penetrating the film. The film is used as a lower film in a floatable cover, with an I.R. pockets being formed between the lower and upper films.

1 . A film for a heat-retaining floating swimming pool cover, comprising: 
 a plastic film; and    an infrared absorbent material contained in said plastic film in an effective amount, but which is insufficient to prevent atmospheric sunlight from substantially penetrating the film.    
     
     
         2 . The film according to  claim 1 , wherein the plastic film is made of vinyl or olefin or acetate.  
     
     
         3 . The film according to  claim 2 , wherein the plastic film has a small amount of tint therein, which amount is only sufficient for cosmetic appearance and which amount does not significantly reduce the transmission of sunlight.  
     
     
         4 . The film according to  claim 1 , wherein the I.R. absorbent is a solid, particulate absorbent.  
     
     
         5 . The film according to  claim 4 , wherein the solid, particulate absorbent is substantially non-reflective.  
     
     
         6 . The film according to  claim 4 , wherein the solid, particulate absorbent is in or on the lower film in an amount of between 0.5 to 8% by weight of the lower film.  
     
     
         7 . The film according to  claim 4 , wherein the I.R. absorbent is talc.  
     
     
         8 . The film according to  claim 7 , wherein the talc is white talc and has an average particle size of between about 0.1 and about 10 microns.  
     
     
         9 . The pool cover of  claim 8 , wherein the talc has a specific gravity of between about 2.6 and about 2.9.  
     
     
         10 . The film according to  claim 1 , wherein the amount of I.R. absorbent is sufficient to generate substantial heat.  
     
     
         11 . The film according to  claim 10 , wherein the plastic film is sealed to a second film so as to form air pockets and wherein the heat generated is sufficient to heat the air in the air pockets.  
     
     
         12 . The film according to  claim 11 , wherein the amount of I.R. absorbent is sufficient to generate heat so that pool water next to said film is substantially heated.  
     
     
         13 . The film according to  claim 12 , wherein the amount of infrared absorbent is such that sunlight passing through the film is capable of substantially heating the pool water.  
     
     
         14 . The film according to  claim 13 , wherein the amount of infrared absorbent is sufficient to generate heat in the air of the air pockets, and sunlight passing through the cover is capable of substantially heating the pool water.  
     
     
         15 . The film according to  claim 1 , wherein the film has a thickness of between 1-40 mm.