CA2346538A1

CA2346538A1 - Uv stabilized spunbond fabrics with enhanced trapezoidal tear

Info

Publication number: CA2346538A1
Application number: CA002346538A
Authority: CA
Inventors: Ramesh Srinivasan
Original assignee: Bba Nonwovens Simpsonville, Inc.; Ramesh Srinivasan
Current assignee: Fitesa Simpsonville Inc
Priority date: 1998-10-05
Filing date: 1999-10-04
Publication date: 2000-04-13
Also published as: EP1128956A1; AU1311100A; EP1128956A4; WO2000020209A1; US6492287B1; WO2000020209A9

Abstract

A nonwoven fabric with UV stability having a spunbonded fabric layer (2) comprising a base resin selected from the group consisting of polypropylene and polyethylene; combined with melt processable additives; wherein said mel t processable additives are a mixture of (i) at least two hindered amine light stabilizers; (ii) a processing aid selected from the group consisting of hydroxyl amines and phosphites; and (iii) a carrier resin selected from the group consisting of polypropylene and polyethylene. Other melt processable additives include pigments which are added to provide the desired color in t he resulting fabric layer.

Description

W STABILIZED SPUNBOND FABRICS
WITH ENHANCED TRAPEZOIDAL TEAR
Related Application This application claims the benefit of U.S.
5 Provisional App:Lication No. 60/103, 113, filed on October 5, 1998, which is incorporated in its entirety herein by reference.
Field of the Invention The invention relates to spunbonded nonwoven 10 fabrics posse:~sing light stability, particularly ultraviolet, su:Ltable for substrates used to manufacture outdoor covers. In particular, the invention relates to nonwoven fabrics made using a combination of at least two hindered amine light stabilizers, hydroxyl amine and 15 phosphite processing aids; and a carrier resin of polypropylene, polyethylene or a mixture of both. The resulting spunbonded fabric layer has enhanced trapezoidal tear in both the MD and CD directions.
Background of the Invention 20 Nonwoven fabrics possessing light stability (particularly ultraviolet) are desirable for use as substrates to manufacture outdoor covers. Outdoor covers include marine, automobile, bike and recreational vehicle covers.. Such covers include protecting the 25 vehicle from wear and tear caused by wind, rain and sunlight. Nonwovens and nonwoven composites for such covers are avai:Lable in the market . However, it was not possible hitherto to incorporate UV stability and still obtain high fabric strength, particularly trapezoidal 30 tear strengths needed for downstream ultrasonic converting. To overcome these problems the invention provides a nowoven product and process for producing such a fabric, having enhanced trapezoidal tear, WO 00/20209 PC'f/US99/22868

-2-suitable far further ultrasonic lamination.
In general hindered amine light stabilizers (HALS) are known in thcs art. For example, published European patent application EP 0792911 A2 to Tennesen discloses 5 a phosphate based flame retardant combined with alkoxyamine functional hindered amine light stabilizer (NOR-HALS) used to achieve flame retardant properties that are better than those with phosphates alone.
U . S . Patent: No . 5 , 3 93 , 812 to Haley describes f fibers 10 and fabrics, as used clothing, upholstery and carpeting which contain about 0.01 to 3% (preferably 0.2 to 1.0%) by weight of the composition, of a light stabilizer.
This patent dis~~loses a polyolefin, a NOR HALS (alkoxy amine functiona:L hindered amine light stabilizers) and 15 a phosphorous f:Lame retardant (col. 2 line 33-40; col.
4 line 62-64). Regular HALS (hindered amine light stabilizers) may be employed additionally or in place of NOR HALS.
U.S. Patent No. 5,096,950 to Galbo discloses 20 numerous N-OR1 alkoxy hindered amine light stabilizers.
U.S. Patent No. 5,200,443 to Hudson discloses a nonwoven web o:E polypropylene polymer containing an acetylated hindered amine light stabilizer and a hindered amine substituted siloxane.
25 U. S . Patent: No . 5 , 004 , 770 to Cortolano; U. S . Patent No. 5,124,378 t~~ Behrens; U.S. Patent No. 5,939,341 to Brown and U.S. Patent No. 5,300,647 to Malherber all disclose formulations of particular hindered amine light stabilizers.
30 None of they known prior art discloses a spunbonded nonwoven fabric, with UV stability having enhanced durablity. Further, the known art has not disclosed the synergistic effect of combining at least two hindered amine light stabilizers to produce a spunbonded nonwoven 35 fabric having enhanced trapezoidal tear properties.
Thus it i;~ a broad object of the invention to

-3-provide a spun',bonded nonwoven fabric with UV light stability. Specifically, the fabric layer is made of a base (or virgin) resin polypropylene which is combined with melt processing additives. These additives are a 5 mixture of (i) at least two hindered amine light stabilizers (H~~LS); (ii) processing aids which are either hydroxyl amines or phosphates or a combination of both; and (iii) a carrier resin of either polypropylene or polyethylene or a mixture of both.
10 Pigments are also included in the formulations to impart desired color properties to the resulting fabrics. The additives .are :incorporated into a base polyolefinic resin to form a homogeneous blend which is then spunbonded to form the fabric layer.
15 Another object of the invention is to provide a spunbonded fabric structure possessing at least two layers of spunbond (SB) webs to which suitable melt processable additives have been incorporated to the virgin resin before melt spinning.
20 A specific object of the invention is to provide spunbond cover substrates having spunbond-spunbond (SS), spunbond-spunbo:nd-spunbond (SSS) and spunbond-spunbond-spunbond-spunbond (SS-SS) composite structures all having enhanced trapezoidal tear strength.
25 Another more specific object of the invention is to provide spunbond structures having a useful service life from six to sixty months, depending on the desired end use.
Another specific object of the invention is to 30 provide a spunbond fabric that possesses superior initial physical properties as measured by grab/strip tensile tests and trapezoidal tear tests.
A further object of the invention is to provide a spunbond fabric that does not suffer a loss of more than 35 50% of its initial MD, CD tensiles and initial MD, CD
trapezoidal tear values at the end of its useful service

-4-life.
A further ;specific object of the invention is to provide a spunbond fabric wherein the color shift is maintained within tolerances over the entire service

5 life.
Summary of the Invention The present: invention provides a spunbond fabric possessing W light stability for use as a substrate to manufacture outdoor covers.
10 The spunbonded fabric comprises a base resin selected from the group consisting of polypropylene and polyethylene combined with melt processable additives.
The melt proces.~able additives are a mixture of (i) at least two hindered amine light stabilizers; (ii) a 15 processing aid selected from the group consisting of hydroxyl amines and phosphites; and (iii) a carrier resin selectecL from the group consisting of polypropylene and polyethylene. Pigments are also included in the formulations to impart desired color 20 properties to the resulting fabrics.
The base reain and melt processable additives are combined to form a homogeneous blend which is then spunbonded to form a nonwoven fabric layer.
The nonwove~n fabric of the invention may comprise 25 multiple fabric layers. Fabric structures encompassed by the invention include spunbond (SB), spunbond spunbond (SS),, spunbond-spunbond-spunbond (SSS), spunbond-spunbond-spunbond-spunbond (SS-SS) nonwoven fabrics.
30 Other objects, features and advantages of the present invention will be apparent when the detailed description of the preferred embodiments of the invention are considered with reference to the drawings, which should be construed in an illustrative and not 35 llimiting sense as follows:

Brief Description of the Drawincrs FIG. 1 is a schematic diagram showing the basic components of a :system for producing the nonwoven fabric in accordance with the process of the invention.
5 Detailed Descrix~tion of the Preferred Embodiments As used Herein, the term "nonwoven web" or "nonwoven fabric" are interchangable and refer to a web/fabric that has a structure of individual fibers or filaments which are interlaid, but not in an 10 identifiable repeating pattern.
As used herein, the term "spunbonded fibers" refers to fibers which are formed by extruding molten thermo-plastic materia7_ as filaments from a plurality of fine, usually circular capillaries of a spinnerette. Cooling 15 air is fed to a quenching chamber wherein the filaments are cooled. The cooling air is then sucked through a nozzle, which accelerates the flow of air. The friction between the flowing air and the filaments creates a force which draws the filaments, i.e., attenuates the 20 filaments to a smaller diameter. The drawn filaments are then passed through a diffusor and deposited on a conveyor belt to form a nonwoven web. A conventional spinbonding technique is disclosed in U.S. Patent No.
4,340,563 to Ap~pel.
25 In genera7_, the invention provides a nonwoven fabric with W stability having a spunbonded fabric layer comprising a base resin selected from the group consisting of ~~olypropylene and polyethylene combined with melt processable additives. The melt processable 30 additives are a~ mixture of (i) at least two hindered amine light stale>ilizers; (ii) a processing aid selected from the grou~~ consisting of hydroxyl amines and phosphites; and (iii) a carrier resin selected from the group consisting of polypropylene and polyethylene.
35 Pigments are al:~o included in the formulations to impart

-6-desired color p~_°operties to the resulting fabrics.
The base re=sin is an olefinic material preferably either polyproy:Lene or polyethylene. In preparing the spunbonded webs of the invention, the base resin is 5 typically present in amounts ranging from 80 to 99 wt%.
The base resin Used must be compatible with the carrier resins in the formulations in order for homogeneous combination of t:he base resin with the melt processable additives. Thus., if the base resin is polypropylene the 10 carrier resin is preferably polypropylene or a combination of polypropylene and polyethylene. A
preferred base resin used in the invention is a polypropylene having a melt flow rate of 35 commercially available as Montel PH805 from Montel Polyolefins, 15 Moltel USA, Wilmington, Delaware.
Preferred hindered amine light stabilizers used in the invention are 1,3,5-Triazine-2,4,6-triamine,N,N " '-[1,2-ethanediylbis[[4,6-bis-[buty(1,2,2,6,6-pentamethyl-4-piperidinyll)amino]-1,3,4-triazin-2-yl]imino]-3,1 20 propanediyl] ]bis [N' ,N" -dibutyl-N' ,N" -bis (1, 2, 2, 6, 6-pentamethyl-4 piperidinyl) commercially available as Chimassorb'r'''l19 from Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada; dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol 25 commercially available as TinuvinT"'622 from Ciba Specialty Che~riicals Canada, Mississauga, Ontario, Canada; Poly[[6-((1,1,3,3,-tetramethyl butyl)amino]-1,3,5-triazine-2,4-diyl][2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene[2,2,6,6-tetramethyl-4-30 piperidyl) imino] ] commerically available as ChimassorbT"' 944 from Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada; and 1,6-Hexanediamine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-polymer with 2,4,6,-trichloro-1,3,5-triazine, reaction products with 35 N-butyl-1-butanamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine commercially available as ChimassorbT'''2020 from Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada. The data sheets for Chimassorbz'''119, 944 and 2020 and Tinuvin'1'''622 are all incorporated herein by reference.
At least two hindered amine light stabilizers (HALS) are combined in the invention formulations and are preferably ~~ombined in a ratio of 9:1 to 1:9. The total hindered amine light stablizers are present in the resulting fabrics layer in amounts ranging from 1000 ppm to 25,000 ppm. The combination of using two HALS
provides for increased loading of the W stabilizer materials in th~~ final spunbond product. In addition, the synergistic effect of the two HALS result in a product with an increased durability and product life.
The preferred processing aids used in the invention are hydroxyl amine (bis (hydrogenated tallow alkyl) amines, oxidized and Tris(2,4-di-tert-butylphenyl)phosphite These materiale~ are either used in the formulations separately or in combination. The processing aids are present in the i:abric layer in amounts ranging from 100 ppm to 10,000 ppm.
Preferred carrier resins are polyethylenes with a melt index from 1 to 20 and polypropylenes with a melt flow rate between 2 and 60. The carrier resin may also be a mixture of: polypropylene and polyethylene, which is combined in a ratio of 9.5:1 to 1:9.5.
As discussed in more detail herein the fabric layer may further include color pigments added at levels up to 10 wt% to the color concentrate formulations prior to spunbonding.
The melt processable additives are combined together prior to mixing with the base (virgin) resin.
The melt proce;~sable additive formulations preferably have a melt flow rate of less than 35 to aid in producing a homogenous blend. Typically, between 1 to 20 wt% of the melt processable additive formulations are _g_ blended with between 80 to 99 wt% of the base resin.
This blend is then formed into a spunbond web.
The invention also provides a method of making a nonwoven fabric with UV stability having a spunbonded 5 fabric layer by combining a base resin selected from the group consisting of polypropylene and polyethylene with melt processable additives to form a homogeneous blend.
The melt processable additives are a mixture of (i) at least two hindered amine light stabilizers; (ii) a 10 processing aid selected from the group consisting of hydroxyl amines and phosphates; and (iii) a carrier resin selected from the group consisting of polypropylene and polyethylene. The homogeneous blend is spunbonded to form the nonwoven fabric layer.
15 The nonwove;n fabric of the invention can be a single fabric layer but preferably comprises multiple spunbond fabric layers. Fabric structures encompassed by the invention include spunbond (SB), spunbond-spunbond (SS), spunbond-spunbond-spunbond (SSS), 20 spunbond-spunbon.d-spunbond-spunbond (SS-SS).
In an embodiment of the invention, a nonwoven fabric having at least two of the fabric layers is formed by spinbonding the homogeneous blend to form a first and second nonwoven fabric layers followed by 25 thermally bonding the layers together.
In another embodiment of the invention, a nonwoven fabric having at least three of the fabric layers is formed by spinbonding the homogeneous blend to form a first, second and third nonwoven fabric layer followed 30 by thermally bonding the layers together.
In another embodiment of the invention, a nonwoven fabric having at least four of the fabric layers is formed by spinbonding the homogeneous blend to form a first, second, i:hird and fourth nonwoven fabric layer 35 followed by thex-mally bonding the layers together.
FIGURE 1 is a schematic diagram showing the basic _g_ components of a ;system for producing the nonwoven fabric in accordance w:~th the process of the invention.
As previou:~ly described the nonwoven fabric of the invention has a.t least one fabric layer made from a 5 homogeneous blend of a base resin and a combination of melt processable: additives. The blend is spunbonded to form the fabric layer.
The spunbonded fabric layer may be produced by continuously exi:ruding the homogeneous blend through a 10 plurality of fine, usually circular capillaries of a spinnerette. Pressurized cooling air is fed to a quenching chamber wherein the filaments are cooled. The cooling air is then accelerated through a nozzle by a positive air pressure. The friction between the flowing 15 air and the filaments creates a force which draws the filaments, i.e., attenuates the filaments to a smaller diameter. The filaments are drawn to achieve molecular orientation and tenacity. The continuous filaments are then deposited :i.n a substantially random manner to form 20 a web of substantially continuous and randomly arranged, molecularly oriented filaments. The preferred base polyolefinic re;~in used to make spunbonded fabric layers is polypropylene, although nylon, polyethylene, polyester, and copolymers and blends thereof can be 25 used.
The nonwoven fabric of the invention has a least one layer. Mu7_tiple fabric layers are encompassed by the invention, with numerous variations of spunbonded fabric layers possible . Multiple fabric layers are then 30 bonded together in one-step by the application of heat and pressure t.o form the desired fabric composite.
Spunbonded fabric layers may be prebonded by heated press rolls providing structural integrity to the f abric .
35 For illustrative purposes, the production of a spunbond-spunbond-spunbond (SSS? fabric structure of the invention is described. The production line illustrated in FIGURE 1 can be operated at a speed in the range of 250 to 600 m/mi.n, preferably about 375 m/min. The equipment of production line 10 consists of an endless 5 foraminous forming belt 12 wrapped around rollers 14 and 16. The belt 12 is driven in the direction shown by the arrows. The production line 10 includes a forming machine which has three stations: spunbond station 18, spunbond station 20 and spunbond station 22. In other 10 embodiments, depending on the desired fabric structure, not all these stations may be operating.
For the SSS structure, first, the spunbond station 18 lays down a web 8 of spunbonded fibers 28 onto the carrier belt 12. Then the spunbond station 20 lays down 15 a web 4 of spunbonded fibers 26 onto the spunbonded web 8. Lastly, the spunbond station 22 lays down a web 6 of spunbonded fibers 30 onto the spunbond web 4.
The spunbond stations 18, 20 and 22 are conventional extruders with spinnerettes which form 20 continuous filaments of a polymer/melt additive and deposit those f~.laments onto the forming belt 12 in a random interlaced fashion. Each spunbond station may include one or more spinnerette heads depending on the speed of the process and the particular polymer being 25 used. Forming spunbonded material is a conventional process well known in the art.
Out of the j=orming machine, the SSS fabric laminate web 2 is then fed through bonding rolls 32 and 34. The surfaces of the bonding rolls 32 and 34 are provided 30 with a pattern of raised lands which apply heat and pressure to thermally spot bond the three layers together. The banding rolls are heated to a temperature which causes the: spunbonded polymer to soften. As the spunbond webs pass between the heated bonding rolls 32 35 and 34, the composite material is compressed and heated by the bonding rolls in accordance with the pattern on the rolls to cre~~te a pattern of discrete bonding areas .
Such discrete area or spot bonding is well known in the art and can be carried out by means of heated rolls or by ultrasonic banding. The bond pattern is selected to 5 provide desired fabric strength characteristics. The pattern bonding area is not limited in accordance with the present invention, although pattern bonding areas in the range of 5-25%, preferably 14-19%, of the total fabric area are, feasible. In the alternative, the 10 laminate can be ultrasonically spot bonded or bonded by hot melt/glue adhesive lamination.
As a further illustration of the process of the invention and in accordance with another embodiment, a spunbonded/spunhonded (SS) fabric laminate is formed by 15 operating only spunbond stations 18 and 22, i.e., spunbond station 20 is turned off. In this case, the bonding rolls 3:? and 34 must be heated to a temperature which causes th~~ spunbonded polymer to soften.
Other fa>r~ric structures encompassed by the 20 invention are f~~rmed as described by the process above and as illustrated in FIGURE 1 with the number of spunbond stations, 18, 20 or 22 depending on the number of layers in the desired end fabric.
In contrast to prior art systems where each 25 spunbond web is formed separately and thermally bonded twice, first tc form the layer and second to form the composite, the present invention provides a one-step thermal bonding process. Specifically, the spunbond webs are laid, i.e. one, two, three, etc, and then 30 thermally bonded together in one-step.
The following examples are for purposes of illustration only and this invention should not be considered to be. limited by any recitation used therein.

An outdoor cover spunbond substrate possessing W
stability with enhanced trapezoidal trap tear properties was produced.
5 A W color concentrate was prepared mixing the following ingredients:
(1) 15 wt% of a mixture of hindered amine light stabilizers consisting of a 9:1 ratio of 1,3,5-Triazine-2,4,6-triamine,N,N " '-[1,2-ethanediylbis[[4,6-bis-10 [butyl1,2,2,6,6-pentamethyl-4-piperidinyll)amino]-1,3,4-triazin-2-yl] imi:no] -3,1 propanediyl] ] bis [N' ,N' ' -dibutyl-N',N " -bis(1,2,2,6,6-pentamethyl-4 piperidinyl) (commerically available as Chimassorb'~"'119) and dimethyl succinate polymer with 4-hydroxy-2,2,6,6-15 tetramethyl-1-piperidineethanol (commerically available as Tinuvin~622 ) . Both ChimassorbT°''ll9 and Tinuvin'~''622 are available i_rom Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada.
(2) 5 wt% of a processing aid consisting of a 1:1 20 ratio of hydroxyl amine (bis(hydrogenated tallow alkyl)amines oxidized and Tris(2,4-di-tert-butylphenyl) phosphite (commE:ricially available as Fiberstab'r'"' FS 301 system by Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada).
25 (3) The remaining amount of the concentrate consists of a polypropylene carrier resin which, in this example, includes a brilliant W blue pigment commericially available from Standridge Color Corporation, Social Circle, Georgia. The polypropylene 30 carrier resin used has a melt flow rate of 4 and is available commercially from Montel Canad, Varennes, Quebec, Canada. The amount of pigment in the W color concentrate forvmulations was up to 40 wt.%, preferably up to 10 wt%.
35 5 wt% of th.e W color concentrate was then combined with 95 wt% oi: base polypropylene resin to form a homogeneous blend. The base polypropylene used was Montel PH805, available from Montel Polyolefins, Montel USA Inc., Wilmington, Delaware, and has a 35 melt flow rate. This blend was spunbonded to form a nonwoven 5 fabric layer.
Samples were then made of a nonwoven fabric having at least two of the spunbonded fabric layers (SS
structure). The homogeneous blend was spunbonded to form first and second nonwoven fabric layers which were 10 then thermally bonded together. The SS sample laminates were made at 28.4 gsy and 56.7 gsy. Physical properties and measurements of these samples were taken and summarized, respectively, in TABLES 1 and 2 below.

15 28.4 gsy BRILLIANT W BLUE SPUNBOND (SS) NO BASIS CD GRABCD h!D h1D CALIPERMD CD
WT. TENSILEGRAB GRAB GRAB mils TRAP TRAP
sy /in ELONGtTENSILEELONGt TEAR, TEAR, /in a gms 1 29.30 6157.00198.609026.00108.0012.80 6082.003551.00 2 29.22 6190.00127.309659.00105.9013.95 5902.003811.00 3 28.51 6074.00138.108701.00114.4012.75 5312.003665.00 ' 2 4 29.09 6287.00149.309656.0097.20 12.97 5872.003484.00 56.7 gsy BRILLIANT UV BLUE SPUNBOND (SS) NO BASIS CD GRABCD 140 MD CALIPERh>D CD TRAP
WT. TENSILEGRAB GRAB GRAB mile TRAP TEAR, s /in ELONG!TENSILESLONGt TEAR, gms /in s 2 5 56.82 14750.0153.1019940.0122.5018.59 12070.008843.00 6 57.19 13690.0134.2018810.0109.9018.77 11600.007999.00

7 57.60 14300.0136.5019530.0112.3018.99 11970.008176.00

8 57.64 13700.0136.2019720.0126.6018.06 11390.008315.00

9 57.56 14400.0139.7018650.0115.4019.20 13770.008054.00 3 10 57.81 13940.0135.4019180.0118.6018.67 12130.007912.00 ~

I
11 57.07 13850.0142.9019790.0106.8018.81 10960.007789.00 12 57.88 14970.0147.0019150.0113.5019.38 10900.007727.00 Several variations of the nonwoven fabric made in 35 this example in accordance with the invention process are possible. Although the fabric structure is WO 00/20209 PCT/IlS99/22868 described in this example as SS composite structure, other additional composites are possible. Examples include SS, SSS, SSSS, or other combinations. Such composites are made in a one-step process wherein all 5 the layers are eventually thermally bonded together.
An advantage of this invention over prior practice in this area is in the provision of spunbonded nonwoven fabrics having enhanced trapezoidal tear.

10 Samples 13 to 28, summarized in TABLE 3 below, illustrate various melt processable additive formulations that are used to produce spunbonded fabric layers in accordance with the process of the invention.
The wt%'s :Listed in TABLE 3 refer to the additive 15 formulations. These formulations are combined in amounts ranging between 1 to 20 wt% with a base resin of either polypropylene or polyethylene in amounts ranging between 80 to 99 wt% to form a blend that is then spunbonded into a fabric layer.
20 The total amount of hindered amine light stabilizers (HALS) present in the resulting spunbond fabric layer from each Sample is also indicated in TABLE
3.
In general, in Samples 13 to 28 the melt 25 processable additives contain:
(1) a mixture of two hindered amine light stabilizers (HALS) consisting of HAL-1 which is 1,3,5-Triazine-2,4,6-triamine,N,N "'-[1,2-ethanediylbis[[4,6-bis-[butyl1,2,2,6,6-pentamethyl-4-piperidinyll)amino]-30 1,3,4-triazin-2-yl]imino]-3,1 propanediyl]]bis[N',N " -dibutyl-N',N " -bis(1,2,2,6,6-pentamethyl-4piperidinyl) (commerically available as Chimassorb~119); combined with HAL-2 which is dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol 35 (commerically available as Tinuvin~622). Both Chimassorb°119 and Tinuvin° are available from Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada.
(2) a processing aid ("Process Aid") consisting of 5 a 1:1 ratio of hydroxyl amine (bis(hydrogenated tallow alkyl)amines oxidized and Tris(2,4-di-tert-butylphenyl) phosphite (comme:ricially available as Fiberstab FS 301 system by Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada;i.
10 (3) The remaining melt processable additives consist of either a polypropylene or polyethylene carrier resin in combination with a pigment. The polypropylene carrier resin ("PP") used in the formulations have a melt flow rate between 2 and 35.
15 The polyethylene carrier ("PE") used in the sample formulations have a melt index between 1 and 20.

MELT PROCESSABLE ADDITIVE FORMULATIONS

2 N0. RESIN 1 t AID & CARRIERTOTAL HALS
O t RESIN ON
~ FABRIC, m 13 PP 1.5 0.17 1 97.33 300-1,000 14 PE 1.5 0.17 1 97.33 300-1,000 15 PP 4.5 0.5 1.67 93.33 1,000-2,500 16 PE 4.5 0.5 1.67 93.33 1,000-2,500 2 17 PP 0.9 0.1 2.5 87.5 2,000-5,000 18 PE 0.9 0.1 2.5 87.5 2,000-5,000 19 PP 14.4 1.6 2.5 81.5 3,200-8,000 20 PE 14.4 1.6 2.5 81.5 3,200-8,000 21 PP 16.2 1.8 4 78 3,600-9,000 3 22 PE 16.2 1.8 4 78 3,600-9,000 O

23 PP 22.5 2.5 3 72 5,000-12,500 24 PE 22.5 2.5 3 72 5,000-1,2500 25 PP 29.7 3.3 9 63 6,600-16,500 26 PE 29.7 3.3 4 63 6,600-16,500 3 27 PP 37.5 4.17 5 53.33 16,500-21,000 28 PE 37.5 4.17 5 53.33 16,500-21,000 In TABLE :3 , Examples 27 and 28 have the highest amounts of UV HA:LS in the spunbonded product, 16,500 to 21, 000 ppm, and provide a fabric having a longer service life and greater durablity.
Examples 3 t.o 11 below illustrate nonwoven fabrics 5 with W stability having a spunbonded fabric layer made in accordance with the invention. In general the fabric layers of these examples include 80 to 99.0 wt% of a base polypropylene resin; up to 10 wt% of an ultraviolet color concentrate and up to 10 wt% of an ultraviolet 10 augmentor formulation. Both the ultraviolet color concentrate and augmentor formulations have melt flow rates less than 35.
The ultra~Jiolet color concentrates have the following general formula:
15 15.0 to 50.0 wt% of a mixture of hindered amine light stabilize~__~s;
up to 10.0 wt % of a processing aid;
up to 10.0 wt% pigments; and the remainder of the formulation comprising a 20 polypropylene c~~rrier resin.
The hindered amine light stabilizers in the color concentrate of Examples 3-10 are a mixture of Chimassorb'1'"' 119 and Tinuvin'r"'622 , and Example 11 is a mixture of Chimassorb~'"' 119 and 2020. TinuvinT'"'622, 25 Chimassorb~'~'"' 11.9 and 2020 are all commericially available from Ciba Specialty Canada, Mississauga, Ontario, Canada.
The processing aid in the color concentrate of Examples 3-11 is the Fiberstab~'"' FS 301 system 30 commericially available by Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada, which is a 1:1 combination of hydroxyl amine (bis(hydrogenated tallow alkyl)amines oxidized and Tris(2,4-di-tert-butylphenyl) phosphite. The later component Tris(2,4-di-tert-35 butylphenyl) phosphite is also available separately under the tradename IrgafosT"'168 from Ciba Specialty Chemicals Canada. The data sheet for FS 301 system and IrgafosT"'168 is incorporated herein by reference.
The proces~~ing aid performs the critical function of reducing the :sudden increases in the viscosity of the 5 homopolymer PP, usually caused by the introduction of hindered amines into the polypropylene. Although such function can be performed by traditional phenolic antioxidants, they are known to cause yellowing of the polypropylene fabric, unlike the processing aids used 10 in the invention formulations,.
As mentioned, formulations incorporating the FS 301 processing system are added up to 10 wt%, preferably between 2 - 5 wt:%. In the final spunbond fabric layer the processing ~~id is present in amounts ranging from 15 100 to 10,000 pF~m, preferably between 1000 to 3000 ppm.
The pigments in the formulations are used to impart color. As illustrated in Examples 3-11 various pigments are incorporated into the formulations depending on the desired color of the resulting spunbond fabric. The 20 pigments used include: Natural Brown W, Dark Gull Grey W, Neutral UV Grey, Limestone W Grey, Charcoal W Grey #1, Charcoal Grey #2, Brilliant UV Blue PP, Brilliant UV Blue, Limestone W Grey#2, Desert Dust W #1-PP, Desert Dust W #2-PP, Desert Dust W #1-PE and Desert 25 Dust UV #2-PE: all available commericially from Standridge Color Corporation, Social Circle, Georgia.
The respective data sheets for each of the pigments are incorporated herein by reference. The pigments used include inorganic pigments, organic pigments, metal 30 oxides, combinai=ions of these pigments as well as other materials. The pigments are typically added at levels of up to 40 wts, preferably up to 10 wt%, in the UV
color concentrate formulations.
The selection of the carrier resin is very 35 important in achieving the desired melt flow characteristics of the concentrate. Both polypropylene and polyethylene carrier resins were found to be suitable for incorporating the loadings of the W
stabilizer and the processing aid systems. However, since the UV stabilizers typically have molecular 5 weights significantly lower than that of the homopolymer polypropylene, only polypropylene and polyethylene carriers with t:he right viscosity could be used to produce the fab~~ics of the invention.
Preferred ;polypropylene carrier resins found to 10 result in the highest melt stability in the formulations include Montel ProfaxT"' 6301 and Montel Profax~'' 6501, both in powder form, commericially available from Montell Canada, Varennes, Quebec, Canada. Profaxz''' 6301 has a melt flow rate of 11 and Profaxz'"' 6501 has a melt 15 flow rate of 4. The data sheets for Montel Profaxl'''' 6301 and Montel ProfaxT"' 6501 are incorporated herein by reference.
Preferred polyethylene carrier resins used in the formulations include polyethylene resins having a melt 20 index less than 20, available commericially from Mobil Polymers, Edison, New Jersey.
The ultraviolet augmentor formulations have the following general formula:
15.0 to ~~0.0 wt% of a hindered amine light 25 stabilizer;
1.0 to 5.0 wt % of a phosphite processing aid; and the remainder a carrier resin that is a mixture of polyethylene and polypropylene.
The hindered amine light stabilizer used in the 30 augmentor formu7~ations of Examples 3 to 11 was Poly [ [6 [(1,1,3,3,-tetr<~methylbutyl)amino]-1,3,5-triazine-2,4 d i y 1 ] [ 2 , 2 , 6 , 6 - t a t r a m a t h y 1 - 4 piperidyl)imino]hexamethylene[2,2,6,6-tetramethyl-4 piperidyl)imino:l] which is commerically available as 35 Chimassorb 944 from Ciba Specialty Chemicals Canada, Mississauga, Ontario, Canada. The data sheet for ChimassorbT'"'944 is incorporated herein by reference.
The proces:~ing aid used in augmentor formulations of the Examples was Tris(2,4-di-tert-butylphenyl) phosphite (comme.rcially available as Irgafos'1'"'168) . The 5 carrier resin was a combination of between 2 to 20 wt%
of a low densit5r polyethylene having a melt index of 2 and a polypropylene having a melt flow rate of 4 (commerically a~railable as Montell Profaxz'"' 6501) .
Examples 3 to 11 below are merely illustrative of 10 some of the spunbonded fabrics encompassed by the invention and a~.°e not meant to be limiting.

A spunbond fabric (28.4 gsy) was formed by combining the ZJV Color concentrate formulations, UV
15 augmentor formulations and virgin polypropylene resin as described above. The pigment used in this example was Desert Dust W.
Two layers of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical 20 properties and measurements of this fabric was taken and summarized in TABLE 4. The total amount of hindered amine light stabilizers present in each fabric layer is 7500 ppm.

FABRIC PROPERTIES UNITS VALUE

BASIS WEIGHT a 28.94 hm GRAB TENSILE lbs 19.08 CD GRAB TENSILE lba 14.07 3 19D TRAP TEAR lbs 8.38 CD TRAP TEAR lbs 12.45 Nm ELONGATION t 96.00 CD ELONGATION t 115.00 CALIPER mils 12.83 A spunbon<i fabric (28.4 gsy) was formed by combining the 11V Color concentrate formulations, W
augmentor formulations and virgin polypropylene resin 5 as described above. The pigment used in this example was Limestone LTJ Grey.
Two layers of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical properties and ~rieasurements of this fabric was taken and 10 summarized in 'FABLE 5. The total amount of hindered amine light stabilizers present in each fabric layer is 7500 ppm.

SPUNBC)ND-SPUNBOND FABRIC PROPERTIES
Z FABRIC PROPHRTIES UNITS VALUE

BASIS WEIGHT s 28.85 1~ GRAB TENSILE lbs 19.71 CD GRAB TENSILE lbs 15.82 L~ TRAP TEAR lbs 8.57 2 CD TRAP TEAR lbs 11.07 ~

Nm ELONGATION 6 120 CD ELONGATION ~r 138 CALIPER mils 13.06 25 A spunbon.d fabric (56.7 gsy) was formed by combining the W Color concentrate formulations, W
augmentor formulations and virgin polypropylene resin as described above. The pigment used in this example was Limestone CrV Grey.
30 Two layer:a of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical properties and measurements of this fabric was taken and summarized in 'TABLE 6. The total amount of hindered amine light stabilizers present in each fabric layer is 7500 ppm.

SPUNBOND-SPUNBOND FABRIC PROPERTIES
FAHRIC PROPERTIES UNITS VALUE

5 BASIS WEIGHT a 56.52 14D GRAB TENSILE lbs 44.26 CD GRAB TENSILE lbe 37.21 ~q7 ~Ap TEAR lbs 18.77 CD TRAP TEAR lbs 23.62 1 Nm ELONGATION t 118 O

CD ELONGATION Ir 146 CALIPER mils 18.93 A spunbond fabric (28.4 gsy) was formed by 15 combining the W Color concentrate formulations, UV
augmentor formulations and virgin polypropylene resin as described ax~ove. The pigment used in this example was Natural Brown W.
Two layer: of this fabric were thermally bonded 20 together to form a spunbond-spunbond structure. Physical properties and measurements of this fabric was taken and summarized in '.CABLE 7. The total amount of hindered amine light stabilizers present in each fabric layer is 7500 ppm.

SPUNBOND-SPUNBOND FABRIC PROPERTTES
FABRIC PROPERTIES UNITS VALUE

HASIS WEIGHT s 28.9 hm GRAB TENSILE lba 19.90 3 CD GRAH TENSILE lbs 15.32 O

MD TRAP TEAR lba 8.62 CD TRAP TEAR lba 12.26 hm ELONGATION ~ 101 CD ELONGATION t 129 3 CALIPER mile 12.72 WO 00/20209 PC'T/US99/22868 A spunbond fabric (28.4 gsy) was formed by combining the iTV Color concentrate formulations, W
augmentor formulations and virgin polypropylene resin 5 as described ab~we. The pigment used in this example was Desert Dust UV.
Two layers of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical properties and measurements of this fabric was taken and 10 summarized in TABLE 8. The total amount of hindered amine light stabilizers present in each fabric layer is 13,500 ppm.

SPUNBCIND-SPUNBOND FABRIC PROPERTIES
Z FABRIC PROPERTIES UNITS VALUE

BASIS WEIGHT a 28.13 Nm GRAB TENSILE lba 19.87 CD GRAB TENSILE lba 14.76 Nm TRAP TEAR lbs 8.48 2 CD TRAP TEAR lbs 12.17 hm ELONGATION % 92 CD ELONGATION % 119 CALIPER mils 11.A8 25 A spunbond fabric (28.4 gsy) was formed by combining the W Color concentrate formulations, UV
augmentor formulations and virgin polypropylene resin as described above. The pigment used in this example was Natural Brown W.
30 Two layer~a of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical properties and measurements of this fabric was taken and summarized in 'TABLE 9. The total amount of hindered amine light stabilizers present in each fabric layer is 35 13,500 ppm.

SPUNBOND-SPUNBOND FABRIC PROPERTIES
FABRIC PROPERTIES UNITS VALUE

BASIS WEIGHT s 28.79 ND7 GRAB TENSILE lbs 20.38 CD GRAB TENSILE lbs 19.51 1~ TRAP TEAR lbs 8.47 CD TRAP TEAR lbs 13.73 Nm ELONGATION % 92 1 CD ELONGATION % 137 O

CALIPER mils 12.74 A spunbond fabric (28.4 gsy) was formed by combining the 'W Color concentrate formulations, UV
15 augmentor formulations and virgin polypropylene resin as described above. The pigment used in this example was Limestone UV Grey.
Two layers of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical 20 properties and measurements of this fabric was taken and summarized in TABLE 10. The total amount of hindered amine light stabilizers present in each fabric layer is 13,500 ppm.

FABRIC PROPERTIES UNITS VALUE

BASIS WEIGHT a 28.45 1~ GRAB TENSILE lba 19.05 CD GRAB TENSILE lba 15.93 3 t9D TRAP TEAR lba 7.99 O

CD TRAP TEAR lba 11.93 hm ELONGATION % 94 CD ELONGATION % 132 CALIPER mils 12.08 A spunbond. fabric (56.7 gsy) was formed by combining the UV Color concentrate formulations, UV
augmentor formu7.ations and virgin polypropylene resin 5 as described above. The pigment used in this example was Limestone U'~' Grey.
Two layers of this fabric were thermally bonded together to form a spunbond-spunbond structure. Physical properties and measurements of this fabric was taken and 10 summarized in T~~BLE 11. The total amount of hindered amine light stabilizers present in each fabric layer is 13,500 ppm.

SPUNBOND-SPUNHOND FABRIC PROPERTIES

BASIS WEIGHT s 57.28 Nm GRAH TENSILE lbs 43.30 CD GRAH TENSILE lbs 32.90 Nm TRAP TEAR lbs 18.00 2 CD TRAP TEAR lbs 26.80 Nm ELONGATION t 100 CD ELONGATION % 141 CALIPER mile 18.63 25 A spunbond fabric (101.7 gsy) was formed by combining the i;TV Colar concentrate formulations, UV
augmentor formulations and virgin polypropylene resin as described above. The pigment used in this example was Dark Gull Gray UrV.
30 Three layers of this fabric were thermally bonded together to form a spunbond-spunbond-spunbond structure.
Physical properties and measurements of this fabric was taken and summarized in TABLE 12. The total amount of hindered amine :Light stabilizers present in each fabric 35 layer is 14,000 ppm.

SPUNBOND-SP~UNBOND-SPUNBOND FABRIC PROPERTIES
FABRIC PROPERTIES UNITS VALUE

BASIS WEIGHT gs 101.7 5 hm GRAB TENSILE lbs 50 CD GRAB TENSILE lbs 52 Nm TRAP TEAR lbs 21 CD TRAP TEAR lbs 25 Nm ELONGATION t 59 Z CD ELONGATION t 58 O

CALIPER mils 20.5 Polymer properties timate that in uence the a fiber properties:
in the spunbonded fabric are molecular weight, molecular weight distribution (MWD) and degree 15 of crystallinity.
Generally, the higher the molecular weight and degree of crystallinity, the stronger the final fibers. The MWD determines how the fibers behave in the melt drawn-down stages of fiber formation. This distribution has significant effects on the resultant 20 fibers strength;
and processability.
In view of these polymer properties and due to melt flow rates, chemical reactions and processability factors of the melt processable additives used herein, a spunbonded fabric having UV stability has hitherto not been possible 25 before .

An advanta<~e of this invention over prior practice in this area is in the provision of spunbonded nonwoven fabrics that hive UV light stability and maintaining high fabric strength, particularly enhanced trapezoidal 30 tear strengths.
The preferred embodiments of the invention have been disclosed for the purpose of illustration. Variations and modifications of the disclosed preferred embodiments which fall within the concept of this invention have been described and will 35 also be readily apparent to persons skilled in the art.

All such variations and modifications are intended to be encompassed by the claims set forth hereinafter.

Claims

1. A nonwoven fabric with UV stability having a spunbonded fabric layer comprising:
a base resin selected from the group consisting of polypropylene and polyethylene;
combined with melt processable additives;
wherein said melt processable additives are a mixture of (i) at least two hindered amine light stabilizers;
(ii) a processing aid selected from the group consisting of hydroxyl amines and phosphates; and (iii) a carrier resin selected from the group consisting of polypropylene and polyethylene.

2. The nonwoven fabric as defined in Claim 1 wherein said hindered amine light stabilizers are selected from the group consisting of 1,3,5-Triazine-2,4,6-triamine,N,N'''-[1,2-ethanediylbis[[4,6-bis-[buty(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,4-triazin-2-yl] imino] -3,1 propanediyl]] bis [N', N'' -dibutyl-N',N''-bis(1,2,2,6,6-pentamethyl-4 piperidinyl);
dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; Poly[[6-[(1,1,3,3,-tetramethyl butyl)amino]-1,3,5-triazine-2,4-diyl][2,2,6,6-tetramethyl-4-piperidyl)amino]hexamethylene[2,2,6,6-tetramethyl-4-piperidyl)imino]]; and 1,6-Hexanediamine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-polymer with 2,4,6,-trichloro-1,3,5-triazine, reaction products with N-butyl-1-butanamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine.

3. The nonwoven fabric as defined in Claim 2 wherein said at least two of said hindered amine light stabilizers are combined in a ratio of 9:1 to 1:9.

4. The nonwoven fabric as defined in Claim 1 wherein the total hindered amine light stablizers present in the fabric layer are in amounts ranging from 1000 ppm to 25,000 ppm.

5. The nonwoven fabric as defined in Claim 1 wherein said processing aids are hydroxyl amine(bis(hydrogenated tallow alkyl)amines, oxidized and Tris(2,4-di-tert-butylphenyl)phosphite.

6. The nonwoven fabric as defined in Claim 1 wherein said processing aids are present in the fabric layer in amounts ranging from 100 ppm to 10,000 ppm.

7. The nonwoven fabric as defined in Claim 1 wherein said carrier resin is polyethylene with a melt index from 1 to 20.

8. The nonwoven fabric as defined in Claim 1 wherein said carrier resin is polypropylene with a melt flow rate between 2 and 60.

9. The nonwoven fabric as defined in Claim 1 wherein said carrier resin is a mixture of polypropylene and polyethylene combined in a ratio of 9.5:1 to 1:9.5.

10. The nonwoven fabric as defined in Claim 1 wherein said melt processable additives have a combined melt flow rate less than 35.

11. The nonwoven fabric as defined in Claim 1 wherein the fabric layer further comprises color pigments added at levels up to 10 wt%.

12. The nonwoven fabric as defined in Claim 1 having at least two of the spunbonded fabric layers thermally bonded together.

13. The nonwoven fabric as defined in Claim 1 having at least three of the spunbonded fabric layers thermally bonded together.

14. The nonwoven fabric as defined in Claim 1 having at least four of the spunbonded fabric layers.

15. A nonwoven fabric with UV stability having a spunbonded fabric layer comprising:
(a) 80 to 99.0 wt% of a base resin selected from the group consisting of polypropylene, polyethylene, polyester and polyamide;
(b) up to 10% of an ultraviolet color concentrate comprising:
(i) at least two hindered amine light stabilizers;
(ii) a processing aid selected from the group consisting of hydroxyl amines and phosphates;
(iii) a carrier resin selected from the group consisting of polypropylene and polyethylene; and (iv) pigments; and (c) up to 10% of an ultraviolet augmentor comprising:
(i) a hindered amine light stabilizer;
(ii) a processing aid selected from the group consisting of phosphates; and (iii) a carrier resin comprising a low density polyethylene having a melt flow index of less than 20 and polypropylene.

16. The nonwoven fabric as defined in Claim 15 wherein said hindered amine light stabilizers are selected from the group consisting of 1,3,5-Triazine-2,4,6-triamine,N,N'''-[1,2-ethanediylbis[[4,6-bis-[butyl],2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,4-triazin-2-yl]imino]-3,1 propanediyl]]bis[N',N''-dibutyl-N',N''-bis(1,2,2,6,6-pentamethyl-4 piperidinyl);
dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; Poly[[6-[(1,1,3,3,-tetramethyl butyl)amino]-1,3,5-triazine-2,4-diyl][2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene[2,2,6,6-tetramethyl-4-piperidyl)imino]]; and 1,6-Hexanediamine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-polymer with 2,4,6,-trichloro-1,3,5-triazine, reaction products with N-butyl-1-butanamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine.

17. The nonwoven fabric as defined in Claim 16 wherein said ultraviolet color concentrate contains at least two of said hindered amine light stabilizers which are combined in a ratio of 9:1 to 1:9.

18. The nonwoven fabric as defined in Claim 15 wherein the total hindered amine light stablizers are present in the fabric layer in amounts ranging from 1000 ppm to 25,000 ppm.

19. The nonwoven fabric as defined in Claim 15 wherein said processing aids are hydroxyl amine(bis(hydrogenated tallow alkyl)amines, oxidized and Tris(2,4-di-tert-butylphenyl)phosphite.

20. The nonwoven fabric as defined in Claim 15 wherein said processing aids are present in the fabric layer in amounts ranging from 100 ppm to 10,000 ppm.

21. The nonwoven fabric as defined in Claim 15 wherein said carrier resin is polypropylene with a melt flow rate between 2 and 60.

22. The nonwoven fabric as defined in Claim 15 wherein said carrier resin is a mixture of polypropylene and polyethylene combined in a ratio of 9.5:1 to 1:9.5.

23. The nonwoven fabric as defined in Claim 1 wherein said ultraviolet color concentrate and said ultraviolet augmentor each have a melt flow rate less than 35.

24. The nonwoven fabric as defined in Claim 15 wherein said pigments are added at levels up to 10 wt%.

25. The nonwoven fabric as defined in Claim 15 having at least two of the spunbonded fabric layers thermally bonded together.

26. The nonwoven fabric as defined in Claim 15 having at least three of the spunbonded fabric layers thermally bonded together.

27. The nonwoven fabric as defined in Claim 15 having at least four of the spunbonded fabric layers.

28. A method of making a nonwoven fabric with UV
stability having a spunbonded fabric layer comprising the steps of:
combining a base resin selected from the group consisting of polypropylene and polyethylene with melt processable additives to form a homogeneous blend;
wherein said melt processable additives are a mixture of (i) at least two hindered amine light stabilizers;
(ii) a processing aid selected from the group consisting of hydroxyl amines and phosphates; and (iii) a carrier resin selected from the group consisting of polypropylene and polyethylene; and spinbonding said homogeneous blend to form the nonwoven fabric layer.

29. The method according to Claim 28 wherein said hindered amine light stabilizers are selected from the group consisting of 1,3,5-Triazine-2,4,6-triamine,N,N'''-[1,2-ethanediylbis[[4,6-bis-[butyl(,2,2,6,6-pentamethyl-4-piperidinyll)amino]-1,3,4-triazin-2-yl]imino]-3,1 propanediyl]]bis[N',N''-dibutyl-N',N''-bis(1,2,2,6,6-pentamethyl-4 piperidinyl);
dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol; Poly[[6-((1,1,3,3,-tetramethyl butyl)amino]-1,3,5-triazine-2,4-diyl](2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene[2,2,6,6-tetramethyl-4-piperidyl)imino]]; and 1,6-Hexanediamine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-polymer with 2,4,6,-trichloro-1,3,5-triazine, reaction products with N-butyl-1-butanamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine.

30. The method according to Claim 29 wherein said at least two of said hindered amine light stabilizers are combined in a ratio of 9:1 to 1:9.

31. The method according to Claim 28 wherein said hindered amine light stablizers are added to result in amounts ranging from 1000 ppm to 25,000 ppm in the fabric layer.

32. The method according to Claim 28 wherein said processing aids are hydroxyl amine(bis(hydrogenated tallow alkyl)amines, oxidized and Tris(2,4-di-tert-butylphenyl)phosphite.

33. The method according to Claim 28 wherein said processing aids are added to result in amounts ranging from 100 ppm to 10,000 ppm in the fabric layer.

34. The method according to Claim 28 wherein said carrier resin is polyethylene with a melt index from 1 to 20.

35. The method according to Claim 28 wherein said carrier resin is polypropylene with a melt flow rate between 2 and 60.

36. The method according to Claim 28 wherein said carrier resin is a mixture of polypropylene and polyethylene combined in a ratio of 9.5:1 to 1:9.5.

37. The method according to Claim 28 wherein said melt processable additives have a combined melt flow rate less than 35.

38. The method according to Claim 28 wherein said melt processable additives further comprise color pigments added at levels up to 10 wt%.

39. The method according to Claim 28 wherein the nonwoven fabric has at least two of the spunbonded fabric layers comprising the steps of:
spinbonding said homogeneous blend to form first and second nonwoven fabric layers; and thermally bonding said first and second layers together.

40. The method according to Claim 28 wherein the nonwoven fabric has at least three of the spunbonded fabric layers comprising the steps of:
spinbonding said homogeneous blend to form first, second and third nonwoven fabric layers; and thermally bonding said first, second and third layers together.

41. The method according to Claim 28 wherein the nonwoven fabric has at least four of the spunbonded fabric layers comprising the steps of:
spinbonding said homogeneous blend to form first, second, third and fourth nonwoven fabric layers; and thermally bonding said first, second, third and fourth layers together.

42. The method according to Claim 28, wherein the spunbonded fabric layer has enhanced trapezoidal tear in both the MD and CD directions.