Article made from overmoulded composite material and relative preparation method
An article made from overmolded composite material ( 1 ) having a glass body ( 2 ), consisting of a container or a closing element of a container, and an overmolded jacket ( 3 ) made from thermoplastic resin, characterised in that said glass ( 2 ) is a glass of the sodium-calcium or borosilicate type comprising (percentages in weight referring to the weight of the glass): CaO from 1 to 12% by weight, preferably between 8% and 10% in the case of sodium-calcium glass; preferably between 1% and 3% in the case of borosilicate glass; Al 2 O 3 from 1 to 7% by weight, preferably between 1% and 2% in the case of sodium-calcium glass; preferably between 5% and 7% in the case of borosilicate glass; one or more oxides selected from the group consisting of ZnO, TiO 2 and ZrO 2 .
1. Article made of overmoulded composite material ( 1 ) comprising a glass body ( 2 ) and an overmoulded jacket ( 3 ) made of thermoplastic resin, characterised in that said glass ( 2 ) is a sodium-calcium glass comprising (percentages in weight referring to the weight of the glass):
CaO from 8 to 10% in weight;
Al 2 O 3 from 1 to 2% in weight;
one or more oxides selected from among the group consisting of ZnO, TiO 2 and ZrO 2 , at an amount ranging from 0.3 to 3% in weight of each oxide.
2. Article ( 1 ) according to claim 1 , characterised in that ZnO is present at an amount ranging between 0.5% and 2% in weight and/or TiO 2 is present at an amount ranging between 0.5% and 2% and/or ZrO 2 is present at an amount ranging between 0.3% and 1%.
3. Article ( 1 ) according to claim 1 , characterised in that it comprises B 2 O 3
from 1 to 3% in weight.
4. Article ( 1 ) according to claim 1 , characterised in that it comprises MgO
from 1 to 5% in weight.
5. Article ( 1 ) according to claim 1 , characterized in that it comprises MgO from 1 to 3% in weight.
6. Article ( 1 ) according to claim 1 , characterised in that said thermoplastic resin is an ionomer resin consisting of an ethylene copolymer/methacrylic acid or ethylene/acrylic acid, wherein the acid groups of said methacrylic acid or acrylic acid are at least partially neutralized by sodium ions.
7. Article ( 1 ) according to claim 1 , characterised in that said glass has an iron oxides content lower than 140 ppm.
8. Article according to claim 1 , characterised in that said glass body ( 2 ) comprises a decorative element.
9. Article according to claim 1 , characterised in that said glass body ( 2 ) is coloured.
10. Article ( 1 ) according to claim 1 , characterised in that said thermoplastic resin is transparent or semi-transparent.
11. Article ( 1 ) according to claim 1 wherein at least a portion of said jacket ( 3 ) has a smaller thickness than the thickness of said glass body ( 2 ), said thickness being measured at the point of contact of said portion of jacket with said glass body.
12. Method for making an article made of overmoulded composite material ( 1 ) according to claim 1 comprising a glass body ( 2 ) and an overmoulded jacket ( 3 ) made of thermoplastic resin, said method comprising the following steps:
a) positioning said glass body ( 2 ) in a cavity of a mould;
b) injecting a thermoplastic resin into said mould.
13. Method according to claim 12 , characterised in that said resin is injected into said mould at a temperature equal to or higher than 170° C.
14. Method according to claim 12 , characterized in that said resin is injected into said mould at a temperature between 170° C.-220° C.
15. Method according to claim 12 , characterised in that said resin is injected into said mould at a pressure equal to or lower than 60 bars.
16. Method according to claim 12 , characterized in that said resin is injected into said mould at a pressure between 10-40 bars.
17. Method according to claim 12 , characterised in that said glass body ( 2 ) is previously subjected to a surface treatment for applying a coating based on difluoroethane or aluminium trichloride or tin chlorides or a hot sulfuration treatment.
18. Method according to claim 12 , characterised in that said glass body ( 2 ) is previously subjected to a surface treatment for applying an organic polymer coating with aqueous solutions of polyethylene or oleic acid.