Non-woven of spunbonded thermoplastic filaments having improved weldability properties and method for manufacturing such a non-woven
The object of the present disclosure is a non-woven of spunbonded thermoplastic filaments comprising in a characteristic way, at least 95% by mass (g) of its surface mass (g/m 2 ) of at least two polypropylene A and B polymers, said filaments having a titer of less than or equal to 1.3 dtex, said non-woven having a surface mass of less than or equal to 35 g/m 2 , the welding rate being at least 10% and at most 25% and at least 88% by mass (g) of its surface mass (g/m 2 ) of said polypropylene A polymer obtained by polymerization in the presence of at least one polymerization catalyst based on a metallocene and at most 12% by mass (g) of its surface mass of said polypropylene B polymer.
1 . A non-woven of spunbonded thermoplastic filaments comprising a polymeric mixture, the polymeric mixture consists of a combination of (i) at least 88% by weight of polypropylene A polymer and (ii) from 3 to 12% by weight of a polypropylene B polymer, wherein said non-woven comprises at least 95% by mass (g) of it surface mass (g/m 2 ) of at least the combination of (i) the polypropylene A polymer and (ii) the polypropylene B polymer, said filaments having a titer of from 1.0 dtex to less than or equal to 1.3 dtex, said non-woven having a surface mass of less than or equal to 35 g/m 2 , a welding rate being at least 10% and at most 25%,
wherein said polypropylene A polymer is obtained by polymerization in the presence of at least one polymerization catalyst based on metallocene and said polypropylene B polymer is obtained by polymerization in the presence of a Ziegler-Natta catalyst,
wherein said polypropylene A polymer comprises a first melt flow index that is at least 10 g/10 mins and at most 35 g/10 mins according to ISO 1133 standard, condition L, at 230° C. and with 2.16 kg, and said polypropylene B polymer comprises a second melt flow index that is at least 600 g/10 mins and at most 3,000 g/10 mins according to ISO 1133 standard, condition L, at 230° C. and with 2.16 kg; wherein a ratio between the second melt flow index and the first melt flow index is from 86:1-300:1, and
wherein the polypropylene A polymer is a first homopolymer of polypropylene and the polypropylene B polymer is a second homopolymer of polypropylene;
wherein the non-woven is thermally bondable at a bonding temperature from 150° C. to 160° C., and wherein the non-woven has a machine-direction elongation from 50.1% to 75% at break as determined by WSP 110.4(09); and wherein the non-woven has a perviousness (l/m 2 /s) measured according to the ISO 9237 standard from 1995 of less than 6,500 l/m 2 /s.
2 . The non-woven according to claim 1 , wherein said non-woven comprises at least 93% by mass of its surface mass of said polypropylene A polymer.
3 . The non-woven according to claim 1 , wherein the filaments have a titer comprised between 1.0 dtex and 1.2 dtex.
4 . The non-woven according to claim 1 , wherein said non-woven has a surface mass of at least 5 g/m 2 and of at most 30 g/m 2 .
5 . The non-woven according to claim 4 , wherein said non-woven has a surface mass of at least 10 g/m 2 and at most 25 g/m 2 .
6 . The non-woven according to claim 1 , wherein said non-woven comprises 9.5 km of filaments per m 2 .
7 . The non-woven according to claim 1 , wherein said non-woven has a perviousness (I/m 2 /s) measured according to the ISO 9237 standard dating from 1995 of less than 6,100 l/m 2 /s.
8 . An article comprising at least one first non-woven according to claim 1 , and at least one second non-woven comprising fibers and/or filaments based on a polypropylene polymer, said first non-woven and said second non-woven are thermobonded to each other along at least one fastening area.
9 . The article according to claim 8 , wherein said fastening area comprises at least two first non-wovens.
10 . The article according to claim 9 , wherein said fastening area comprises at least four first non-wovens.
11 . The non-woven according to claim 1 , wherein the second melt flow index comprises at least 1200 g/10 mins and at most 3,000 g/10 mins according to ISO 1133 standard, condition L, at 230° C. and with 2.16 kg.
12 . The non-woven according to claim 1 , wherein the non-woven has a first breakage-force-to-percent-elongation ratio in a machine direction of 0.5; wherein a machine direction breakage force has units of Newtons per 5 cm (N/5 cm) as determined according to WSP 110.4(09) and the machine direction elongation is determined according to WSP 110.4(09).
13 . The non-woven according to claim 12 , wherein the non-woven has a second breakage-force-to-percent-elongation ratio in a cross-direction from 0.28 to 0.3; wherein a cross-direction breakage force has units of Newtons per 5 cm (N/5 cm) as determined according to WSP 110.4(09) and the cross-direction elongation is determined according to WSP 110.4(09).
14 . The non-woven according to claim 13 , wherein a weight ratio between the polypropylene A polymer and the polypropylene B polymer is from 90:10 to 95:5.
15 . The non-woven according to claim 1 , wherein the non-woven has a percent elongation ratio between a machine direction elongation and a cross-direction elongation from 0.88 to 0.94 as determined according to WSP 110.4(09).
16 . The non-woven according to claim 1 , wherein the ratio between the second melt flow index and the first melt flow index is from 86:1-120:1.
17 . The non-woven according to claim 1 , wherein the ratio between the second melt flow index and the first melt flow index is from 120:1-300:1.
18 . A non-woven of spunbonded thermoplastic filaments consisting of a polymeric mixture, the polymeric mixture consists of a combination of (i) at least 88% by weight of polypropylene A polymer and (ii) from 3 to 12% by weight of a polypropylene B polymer, wherein said non-woven comprises at least 95% by mass (g) of it surface mass (g/m 2 ) of at least the combination of (i) the polypropylene A polymer and (ii) the polypropylene B polymer, said filaments having a titer of from 1.0 dtex to less than or equal to 1.3 dtex, said non-woven having a surface mass of less than or equal to 35 g/m 2 , a welding rate being at least 10% and at most 25%,
wherein said polypropylene A polymer is obtained by polymerization in the presence of at least one polymerization catalyst based on metallocene and said polypropylene B polymer is obtained by polymerization in the presence of a Ziegler-Natta catalyst,
wherein said polypropylene A polymer comprises a first melt flow index that is at least 10 g/10 mins and at most 35 g/10 mins according to ISO 1133 standard, condition L, at 230° C. and with 2.16 kg, and said polypropylene B polymer comprises a second melt flow index that is at least 600 g/10 mins and at most 3,000 g/10 mins according to ISO 1133 standard, condition L, at 230° C. and with 2.16 kg; wherein a ratio between the second melt flow index and the first melt flow index is from 86:1-300:1, and
wherein the polypropylene A polymer is a first homopolymer of polypropylene and the polypropylene B polymer is a second homopolymer of polypropylene;
wherein the non-woven is thermally bondable at a bonding temperature from 150° C. to 160° C., and wherein the non-woven has a machine-direction elongation from 50.1% to 75% at break as determined by WSP 110.4(09); and wherein the non-woven has a perviousness (l/m 2 /s) measured according to the ISO 9237 standard from 1995 of less than 6,500 l/m 2 /s.