Abstract:
Apparatuses and methods are described for distributing gas which may be applicable in the field of polymer oxidation and melt curtain ozonation in particular. Ozone applicators and other features of ozonation apparatuses, which may be used separately or in combination, are also described.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to apparatuses and methods for distributing gas which may be applicable in the field of polymer oxidation and melt curtain ozonation in particular. Aspects of the invention relate to ozone applicators as well as other features of ozonation apparatuses and associated methods. 
       BACKGROUND OF THE INVENTION 
       [0002]    The extrusion of molten polymers and copolymers, with subsequent bonding of the extruded polymer film or “curtain” onto a substrate, is well known. The process normally involves melting the polymer in an extruder, extruding the molten polymer through a die to form the melt curtain, and passing the substrate (e.g., paper or aluminum foil) and the extruded film simultaneously between two pressure rolls to bond the hot polymer film and the substrate. In a typical operation, plastic resin pellets are melted and extruded through a narrow (e.g., 0.030 inch) linear die opening to form the melt curtain or molten plastic web. Various polymers suitable for extrusion coating include polyolefins (e.g., polyethylene), olefinic copolymers (e.g., ethylene-propylene or ethylene-acrylic acid copolymers), and olefinic polymer blends (e.g., a blend of polypropylene with either polyethylene or polystyrene). 
         [0003]    Extrusion coating is described in detail, for example, in U.S. Pat. No. 4,183,845 and WO 2002/094556. The process may be used in a number of applications, for example in the preparation of labels and decals or packaging materials such as those used in food packaging. 
         [0004]    The adhesion of the molten polymer to the extrudate can be significantly improved with ozone application to the side of polymer melt curtain that contacts the substrate, or otherwise contacts an intermediate layer that adheres to the substrate. In particular, a discharge of ozone in the vicinity of the molten polymer, shortly before it contacts the substrate, provides controlled oxidation on the bonding or “preferred” side of the extrudate. The process known as melt curtain ozonation therefore provides bonding sites on the molten polymer which promote oxidative type bonding. 
         [0005]    Good polymer/substrate adhesion and consequently minimal delamination is critically dependent on the manner in which ozone is applied. Also, the close proximity between the equipment from which ozone is applied (i.e., the ozone applicator) and the molten polymer renders this equipment subject to plugging and/or to becoming caked or coated, both internally and externally, with the polymer or polymer byproducts. This results in uneven ozone distribution and consequently poor adhesion of the finished laminate. Frequent cleaning (e.g., at approximately six-week intervals) of the ozone applicator is therefore often mandatory to combat the deposition and condensation of polymer, both onto and into, the ozone applicator, due to its contact with molten polymer or polymer vapors. 
         [0006]    Thus, there remains a need in the art for improved gas distributors such as ozone applicators, as well as ozonation apparatuses and methods, which can improve the application of ozone in melt curtain ozonation, thereby reducing polymer/substrate delamination as well as the detrimental effects, including decreased operating efficiency, associated with polymer deposition on the ozone applicator. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is associated with the discovery of improved apparatuses and methods of discharging gas, especially ozone-containing gas used in melt curtain ozonation, as discussed above. The apparatuses and methods advantageously improve ozone distribution across the width of the molten polymer film, resulting in enhanced bonding between the polymer and substrate and consequently reduced delamination in the end product laminate, even for relatively wide laminate sheets. Also associated with the apparatuses and methods of present invention is a reduction in the extent of polymer or polymer byproduct and vapor deposition onto or inside of the ozone applicator during melt curtain ozonation. 
         [0008]    Aspects of the invention therefore relate to an ozone applicator that provides improved distribution of discharged gas, such as ozone-containing gas that is a mixture of ozone gas and a diluent (e.g., air). According to one embodiment, the applicator, or applicator bar, includes elongated, inner and outer shells with the inner shell disposed within the outer shell. The shells may therefore be, for example, nested cylinders with the inner diameter of the outer shell exceeding the outer diameter of the inner shell such that an intermediate (e.g., annular) space is formed between the shells. Other shell geometries are possible and could similarly result in the formation of an intermediate space. 
         [0009]    An inlet stream of gas such as ozone-containing gas flows, or is received, into the interior or innermost space that is surrounded by the inner shell. The gas then flows into the intermediate space through at least one opening such as an elongated aperture (e.g., having an oval shape), or in some cases through a plurality of holes, on the inner shell that allow fluid communication between the interior and intermediate spaces. These one or more elongated apertures or holes (or openings having other shapes) may be distributed along at least a portion of the length of the inner shell. The gas in the intermediate space then exits, or is discharged from, the applicator through at least one outlet on the outer shell that allows fluid communication between the intermediate space and the exterior of the applicator. This outlet may be, for example, in the form of a plurality of holes, or otherwise an elongated slot that extends longitudinally (axially) along at least a portion of the length of the outer shell. 
         [0010]    Advantageously, in the inner/outer shell arrangement described above, the opening or plurality of openings of the inner shell do not align with the outlet of the outer shell. That is, the gas flow through the inner shell opening(s) does/do not coincide with the gas flow through the outer shell outlet (e.g., in the form of a plurality of openings), and typically these flows are in different directions. In many cases, it may be desired to configure the applicator such that the flow through the inner shell opening(s) is/are opposite (at a 180 angle relative to) or substantially opposite (at a 160-200 degree angle relative to) the flow through the outer shell outlet or discharge opening(s). Therefore, the inner shell opening or openings may be aligned substantially opposite the outer shell outlet. 
         [0011]    In this manner, the change in direction of the ozone-containing gas flow through the inner and outer shells can provide a more tortuous or complicated pathway through the ozone applicator and greatly improve distribution of the exiting or discharged gas along its length (e.g., through a plurality of holes or an elongated outlet slot). Variations in the ozone-containing gas flow exiting the applicator bar and contacting the melt curtain are minimized across the applicator bar length and consequently the melt curtain width, even at peripheral or outermost locations. 
         [0012]    In another embodiment, the ozone applicator comprises only a single elongated shell that surrounds the interior space from which an inlet stream of ozone-containing gas is received. In this case, the shell as a plurality of openings that are disposed about a portion of the shell surface (e.g., a cylindrical surface portion) that extends longitudinally (or axially, i.e., parallel to the shell axis) but that is confined to an arcuate section within about 90° (π/2 radians), and often within about 45° (π/4 radians), based upon an arc of a cross-sectional shape (e.g., a circle) of the shell. The openings may be disposed, for example, over an arcuate section of a cylindrical surface, with the arc ranging from about 10° (π/18 radians) to about 60° (π/3 radians), or otherwise disposed over an arcuate section with an arc of about 40° (2π/9 radians). For example, the openings may be holes disposed in longitudinally extending, substantially parallel lines that are separated by an arc angle as described above. In a particular embodiment, two separate, spaced-apart lines of holes extend over a portion (e.g., from about 30% to about 80%) of the shell length, which may be centered over this length, in a staggered conformation such that the holes of one line are in different axial positions relative to holes in the other line. 
         [0013]    Gas distributors and particularly ozone applicators as described above provide a uniformly distributed flow of gas across the length of the applicator bar (and consequently the width of the melt curtain). This improvement in flow distribution is especially significant for applicator bar lengths of at least about 61 centimeters (at least about 24 inches), where gas distribution difficulties become significantly more pronounced in the case of conventional ozone applicators. 
         [0014]    Exposing a polymer surface (e.g., an essentially flat surface of a molten extrudate) to ozone discharged from any of the ozone applicator bars described above therefore results in more uniform or even oxidation of the polymer and consequently improved adhesion of the polymer to a substrate, relative to the performance obtained from conventional apparatuses and methods. This improves laminate product quality, especially in the production of wide laminates. Also, compared to conventional applicators, the applicator bar configuration described herein advantageously allows a higher overall gas flow rate to be discharged through the bar, without causing pressure to increase within the ozonation apparatus to a level that could damage key equipment (e.g., dielectric tubes inside the ozone generator) used to generate ozone. These higher gas flows that can be achieved using the applicator described above also beneficially improve ozone distribution and substrate bonding. 
         [0015]    Other aspects of the invention relate to modifications of ozonation apparatuses and particularly those used in melt curtain ozonation, as well as the resulting ozonation processes that result from these modifications. The modifications are associated with ensuring a constant feed of diluent gas (e.g., a substantially non-ozone containing gas such as air) through the ozone applicator. In particular, the use of a continuous supply of diluent gas during the entire melt curtain ozonation process (including non-normal operating periods such as startup and upset conditions, when ozone gas is not flowing through the applicator), provides commercial advantages. Importantly, the rate of accumulation (or build-up) of unwanted polymer or polymer byproduct inside of or on top of the applicator bar, due to its proximity to molten polymer and polymer vapors, is dramatically reduced. Such solids can adhere both within the applicator as a condensate, as well as on external surfaces of the applicator, as a coating or caked material. 
         [0016]    Apparatuses and methods for performing polymer oxidation such as melt curtain ozonation are therefore associated with the discovery of advantages resulting from maintaining an essentially continuous or constant gas flow (i.e., a source of positive pressure), exiting the ozone applicator to minimize or prevent its contact with polymer or polymer vapors. These advantages include improved operating efficiency resulting from increased run time (i.e., less operational downtime associated with cleaning the ozonation equipment). Moreover, reducing blockage of the ozone applicator interior spaces and outlet by vapor and liquid polymer, respectively, prevents loss of the desired, well-distributed gas flow from the applicator outlet, as required for good polymer/substrate adhesion. 
         [0017]    Accordingly, modifications of the melt curtain ozonation apparatuses, relative to conventional equipment, include piping, tubing, or other conduit connections that allow air or other diluent gas to be constantly fed to the ozone applicator. Therefore, rather than combining or mixing diluent gas and ozone gas prior to a valve or other device that diverts the entire, combined ozone-containing gas stream away from the applicator inlet (i.e., interrupts the entire gas flow to the applicator), the diluent gas is added downstream of such a device. For example, diluent air may be added to the ozone applicator through a jet pump, with the outlet of this pump combining with ozone gas downstream of a diverter valve that redirects the ozone gas to a rooftop mounted ozone destruct unit prior to venting. 
         [0018]    The minimization or prevention of “no-flow” situations (e.g., during startup or upset conditions) or the substantial loss of gas flow through the applicator, when in proximity to molten polymer, greatly improves melt curtain ozonation processes. In particular, modifications to maintain continuous gas flow through the ozone applicator have dramatically reduced the extent to which polymer vapors condense within the inside of, or polymer adheres to the outside of, the applicator. Blockage of even a portion of the flow through the applicator (e.g., a portion of an outlet slot) prevents effective, well-distributed ozonation of polymer in melt curtain ozonation processes and adversely impacts polymer adhesion to the substrate. Frequent cleaning of the applicator to remove deposited polymer greatly reduces operating efficiency. 
         [0019]    A further advantage of such flow routing modifications to conventional melt curtain ozonation apparatuses is that the amount of added diluent gas such as air, used to distribute ozone-containing gas across the length of the applicator, can be increased with only a relatively small impact on the reactor pressure within the ozonator. The modifications thus improve the efficiencies of ozone gas production and flow, ozone gas deliverability to the applicator, product quality, and production quantity. The modifications additionally reduce waste and machine downtime for cleaning, without the negative aspects of increased reactor pressure and hardware contamination. 
         [0020]    Aspects of the invention are therefore directed to a melt curtain ozonation apparatus comprising an ozone gas conduit (e.g., comprising piping and/or tubing) that flows ozone gas from an ozone generator to an ozone applicator. The apparatus further comprises a device that allows interruption or diversion of ozone gas flow to the ozone applicator, where the device acts on the ozone conduit (i.e., is in fluid communication with the ozone gas stream) between the ozone generator and the ozone applicator. A diluent gas conduit for flowing diluent gas to the ozone applicator intersects the ozone gas conduit (i.e., provides mixing between the ozone gas and diluent gas streams) downstream of the device. The apparatus may optionally include a pressure regulator, such as a back pressure regulator, downstream pressure regulator, a pressure relief valve, etc. in order to prevent the pressure in the ozone generator from exceeding a maximum value, such as a specified maximum operating pressure. 
         [0021]    Other aspects of the invention relate to melt curtain ozonation methods that involve flowing a mixture of ozone gas and a diluent gas into an ozone applicator, with at least a portion of the diluent gas being mixed with ozone gas downstream of a device, as discussed above, which allows interruption or diversion of ozone gas flow to the applicator. The device used may be a manually or automatically actuated valve, such as a diverter valve or a block valve, which is typically used to redirect or stop ozone gas flow during the ozonation process under certain circumstances such as startup, upset, and emergency conditions (all of which may be considered non-normal operating periods). According to these methods, therefore, ozone gas is stopped, interrupted, or diverted from the ozone applicator, in such circumstances during ozonation, without stopping or interrupting diluent gas flow. Typically, the diluent gas flow is maintained constant during any of these conditions, but it may also be desired in some cases to increase diluent gas flow to maintain a total amount of gas flow through the applicator that is equivalent to the normal flow of combined ozone gas and diluent gas. Otherwise, the diluent gas flow may also be decreased during these non-normal operating periods to a minimum value that is sufficient to prevent deposition or condensation of polymer from the melt curtain, onto or into the ozone applicator. 
         [0022]    The advantageous features relating to ozone applicators and ozonation apparatuses, as discussed above, may be used separately. Otherwise, the use of the applicator configuration with the flow routing improvements provides a combination of benefits that can be exploited in melt curtain ozonation processes wherein a polymer in the form of a molten extrudate is oxidized. 
         [0023]    These and other aspects and features relating to the present invention are apparent from the following Detailed Description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1  depicts an ozone applicator and also separately depicts inner and outer shells of the applicator. 
           [0025]      FIG. 2  depicts a cross-sectional view of an ozone applicator comprising elongated inner and outer shells. 
           [0026]      FIG. 3  depicts a flow configuration for gases to an ozone applicator. 
           [0027]      FIG. 4  depicts inner and outer shells of another representative ozone applicator. 
           [0028]      FIG. 5  depicts a single shell of a further representative ozone applicator. 
           [0029]      FIG. 6  depicts a close-up view of the single shell depicted in  FIG. 5 . 
           [0030]      FIG. 7  depicts a cross-sectional view of the single shell depicted in  FIG. 5 . 
           [0031]      FIG. 8  depicts the use of a coupling or adapter for use with an ozone applicator having a relatively small outer diameter. 
       
    
    
       [0032]    The features of the apparatuses referred to in  FIGS. 1-8  are not necessarily drawn to scale and should be understood to present an illustration of the invention and/or principles involved. Some features depicted in the figures have been enlarged or distorted relative to others, in order to facilitate explanation and understanding. The same reference numbers are used in the figures for similar or identical components or features shown in the various embodiments. Gas distributors such as ozone applicators, as well as melt curtain ozonation apparatuses, as disclosed herein, will have configurations, components, and operating parameters determined, in part, by the intended application and also the environment in which they are used. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0033]    As used herein, for convenience, “ozone” refers to the triatomic oxygen molecule O 3 , while “ozone gas” refers to gas generated in an ozone generator, having a substantially elevated ozone content relative to the ambient surroundings. Typically this ozone content is in the range from about 10 g/Nm 3  (grams per normal cubic meter) to about 1000 g/Nm 3 . “Ozone-containing gas” refers to a mixture that results when ozone gas is mixed with a diluent gas such as air. The ozone-containing gas therefore has a lower ozone content than the ozone gas prior to mixing, typically in the range from about 2 g/Nm 3  to about 500 g/Nm 3 . “Diluent gas” refers to gas that is essentially free of ozone, for example, containing less than about 5 ppm of ozone. Air is a diluent gas, as are inert gases such as nitrogen and argon. Other types of diluent gases include mixtures of air and inert gases (e.g., nitrogen-enriched air), oxygen, or oxygen-enriched air. 
         [0034]    A representative ozone applicator  10  is depicted in  FIG. 1 , as well as component parts, namely an elongated outer shell  12  and an elongated inner shell  14 . In the applicator or “applicator bar”  10 , inner shell  14  is not visible, as it is disposed within outer shell  12 . As shown, both shells  12 ,  14  are cylindrical with a circular cross section, but it will be appreciated that other cross-sectional geometries are possible (e.g., oval, polygonal, etc.). Typically, both shells are of approximately the same length, with shell lengths generally from about 25 to about 356 centimeters (about 10 to about 140 inches), and often from about 61 to about 356 centimeters (about 24 to about 140 inches). Because of their ability to uniformly distribute gas flow over wide widths (e.g., over wide sheets of molten polymer), applicators having lengths of at least about 61 centimeters (about 24 inches) provide considerable advantages. A representative applicator bar length is about 140 centimeters (about 55 inches). 
         [0035]    Inner and outer shells  14 ,  12  may be aligned, for example using set screws  25  that are spaced apart around end cap  26 .  FIG. 1  illustrates a representative end cap  26  having four set screws  25  spaced evenly at 90° angles about the circumference of the edge of end cap  26  that fits over outer shell  12 . The center of end cap  26  may have a receiving hole  27  allowing inner shell  14  to extend through end cap  26  and providing a fixed spatial relationship between inner shell  14  and end cap  26 . Set screws  25  extend through end cap  26  to the exterior surface of outer shell  12  and allow adjustment or movement of outer shell  12  in relationship to inner shell  14  and end cap  26 . Outer shell  12  may therefore be positioned around a common central axis shared with inner shell  14  (e.g., in a concentric manner) or possibly in an offset relationship (i.e., where central axes of inner shell  14  and outer shell  12  are not aligned) if desired. 
         [0036]    A representative cross-section of applicator  10  is shown in  FIG. 2  where outer shell  12  has an inner diameter (or other inner dimension) that exceeds the outer diameter (or other outer dimension) of inner shell  14 . This allows the shells to be spaced apart from each other, so than an intermediate space  18  is formed between the shells  12 ,  14 . In a representative embodiment, the inner diameter (i.d.) and outer diameter (o.d.) of outer shell  12  may be about 19 mm and about 25 mm (about ¾ inches and about 1 inch), respectively. Other inner and outer diameters (e.g., from about 6 mm to about 95 mm (about ¼ to about 3¾ inches) i.d. or from about 12 mm to about 102 mm (about ½ to about 4 inches) o.d.) are possible, depending on the particular application. Likewise, representative i.d. and o.d. ranges for the inner shell are from about 3 mm to about 64 mm (about ⅛ inches to about 2½ inches) and from about 6 mm to about 57 mm (about ¼ inches to about 2¼ inches), respectively, with about 6 mm (¼ inch) i.d. and about 12 mm (½ inch) o.d. being representative. 
         [0037]    As shown in the cross-sectional view of  FIG. 2 , inner shell  14  surrounds an interior space  20  that receives, or is in fluid communication with, a gas stream such as an ozone-containing gas stream during normal operating conditions in a melt curtain ozonation process. After entering interior space  20 , the gas stream flows from interior space  20  to intermediate space  18  through at least one opening  22  of inner shell  14 . In one representative embodiment, inner shell  14  has a plurality of holes  22  (see  FIG. 1 ) that are distributed, or extend longitudinally, along at least a portion of the length of inner shell  14 . Holes  22  may otherwise extend non-linearly, for example, they may be positioned randomly or at predetermined locations about the surface of inner shell  14 . 
         [0038]    In a representative embodiment, holes  22  may extend substantially linearly and be spaced apart evenly (e.g., with centers of adjacent holes being spaced apart at an interval that can range from about 3 mm to about 6 mm (about ⅛ inches to about ¼ inches)) along a portion or section of inner shell  14  that is centered with respect to the overall length of inner shell  14 . The length of this portion or section may be, for example, from about 30% to about 80%, and often from about 50% to about 70%, of the length of the inner shell. According to an exemplary embodiment where the total length of the applicator (meaning the extended length if the applicator is extendible) is about 140 centimeters (about 55 inches), the length of the section having holes may be about 84 centimeters (about 33 inches). Representative hole diameters are from about 0.8 mm to about 6 mm (about 1/32 inches to about ¼ inches), with 1.5 mm to 3 mm ( 1/16 inch to ⅛ inch) diameter holes being typical. 
         [0039]      FIG. 2  illustrates intermediate space  18  as an annular space that is formed between inner shell  14  and outer shell  12 . Other geometries for intermediate space  18  are readily contemplated, depending on the geometry of inner shell  14  and outer shell  12  and their relative positioning (e.g., whether they are concentrically positioned or otherwise offset). Gas such as ozone-containing gas flowing into intermediate space  18  may be discharged from applicator  10  through at least one outlet  24  on outer shell  12 . Outlet  24 , like opening  22 , may comprise a plurality of holes through outer shell  12  which may be configured (in terms of spacing, positioning, and length and direction of extension) as described above with respect to holes  22  on inner shell  14 . Another exemplary outlet  24  or outer shell  12  is in the form of an elongated slot  24  that extends along at least a portion of the length of outer shell  12 . 
         [0040]    As with holes  22 , described above, slot  24  may extend substantially linearly along a portion or section, in this case of outer shell  12 , that is centered with respect to the overall length of outer shell  12 . The length of this portion or section may be, for example, from about 30% to about 80%, and often from about 50% to about 70%, of the length of outer shell  12 . According to an exemplary embodiment where the total length of the applicator (meaning the extended length if the applicator is extendible) is about 55 inches, the length of the slot is about 33 inches. Representative slot widths are from about 0.8 mm to about 6 mm ( 1/32 inches to about ¼ inches), with 1.5 mm ( 1/16 inches) being typical. Alternatively, slot  24  may extend non-linearly, such as in a helical or wave form on the surface of outer shell  12 . The slot width may be adjusted, for example, using one or more adjustment screws  16  positioned on outer shell  12  that regulate the amount of force acting to close slot  24  (e.g., by tensioning a clamshell type closure). Other suitable hardware may be used for adjusting the width of slot  24 , thereby providing an independent mechanism for controlling the linear velocity of gas exiting slot  24  of applicator  10  (i.e., with a smaller opening directionally increasing gas linear velocity for a given volumetric flow rate). In the case of melt curtain ozonation, fine adjustments to the flow rate of ozone-containing gas, by changing the width of slot  24 , may be employed to obtain uniform gas distribution without disruption of the nearby melt curtain (or even to optimize this tradeoff). 
         [0041]    As discussed above, the distribution of gas such as ozone-containing gas from slot  24  of applicator  10  is highly uniform, even in the case of applicator lengths exceeding about 24 inches. Exceptional distribution characteristics have been found to result when any of the applicators described herein having inner and outer shells is configured so that gas pressurized from interior space  20  is forced in different directions through opening  22  and outlet  24  before being discharged. That is, the gas flow direction through opening  22  does not coincide with that through outlet  24 , and often these flows are in different directions. It may be desired to configure applicator  10  such that the flows through opening  22  and outlet  24  are in opposite directions. For example, as shown  FIG. 2 , gas flow from interior space  20  to intermediate space  18  is to the left, through opening  22  (e.g., a hole), whereas gas flow from intermediate space  18  to the exterior of applicator  10  is to the right, through outlet  24  (e.g., a slot). In this manner, the alignment of opening  22  and outlet  24  in opposite or substantially opposite directions significantly benefits the overall flow distribution of gas exiting applicator  10 . 
         [0042]      FIG. 4  illustrates the use of an outlet on outer shell  12  in the form of a plurality of holes  22  distributed along a portion of the total length of outer shell  12 . Holes  22  of outer shell in  FIG. 4  may therefore be sized, spaced, and configured about the length of outer shell, in the same manner as discussed above with respect to inner shell  14 . In the particular embodiment shown in  FIG. 4 , inner shell  14  has only one opening, namely a single elongated aperture  45  that can advantageously extend over the midpoint of the length of inner shell  14 . In other embodiments, an inner shell having two, three, or more elongated apertures (e.g., extending in an axial line) centered about the length of the inner shell may also be used. A typical aperture  45 , as an opening in inner shell  14  in the embodiment shown in  FIG. 4 , is elongated in the longitudinal or axial direction. A representative elongated aperture will have a length ranging from about 6 mm to about 25 mm (about ¼ inches to about 1 inch) and a width ranging from about 1.5 mm to about 6 mm (about 1/16 inches to about ¼ inches). 
         [0043]    The central location of elongated aperture(s) provides a good distribution of gas exiting into the intermediate space and then discharging through the outlet of outer shell  12 , for example the plurality of holes shown in  FIG. 4 . As discussed herein with respect to  FIG. 2 , the one or more openings (e.g., elongated aperture(s)) of inner shell  14  in the embodiment of  FIG. 4  preferably do not align with openings such as holes  22  of outer shell  12 . This increases the complexity of the gas flow path (i.e., by preventing gas in the intermediate space between shells from flowing without any encumbrance through a discharge opening) and thereby improves flow distribution. Preferably, the one or more elongated aperture openings of the inner shell are aligned substantially opposite the holes or other openings in the outer shell. 
         [0044]      FIG. 5  illustrates yet another embodiment of an ozone applicator with improved gas flow distribution. This embodiment lacks an inner shell, and instead utilizes a single elongated shell  12  that surrounds an interior space for receiving gas (e.g., containing ozone). The shell  12  has a plurality of openings for discharging this gas, with the openings being disposed about part of its surface. This part of the surface may be limited in its radial direction, axial direction, or both. For example, the axial or longitudinal dimension over which the holes  22  or other openings extend may be limited in the manner discussed above with respect to the plurality of holes extending along at least a portion (e.g., from about 30% to about 80%) of the length of inner shell  14  in the embodiment illustrated in  FIG. 1 , or along at least a portion of the length of outer shell  12  in the embodiment of  FIG. 4 . The plurality of openings or holes  22  in shell  12  can therefore be disposed along a portion of this length that is centered with respect to the total length of the shell. In terms of the radial or circumferential dimension of the surface over which the holes are disposed, this dimension preferably confines or limits the surface to an arcuate section within about 90° (π/2 radians), and often within about 45° (π/4 radians), based upon an arc of a cross-sectional shape (e.g., a circle) of the shell. 
         [0045]      FIG. 6  provides a close-up view of the features of shell  12  of the ozone applicator bar of  FIG. 5 . Holes  22  are disposed about a part  46  of the total surface area of shell  12 . This part  46  of the total surface is confined to acute arc A, as shown in  FIGS. 6 and 7 , with this arc corresponding to a curved, circular section (or possibly a section of another cross-sectional shape of shell  12 ). The arc is normally that of an acute angle, and is often in the range from about 20° (π/9 radians) to about 45° (π/4 radians). As is detailed in  FIG. 7 , the part  46  of the surface over which holes  22  are disposed may have a smaller thickness relative to that of the rest of shell  12 .  FIG. 7  shows a particular embodiment in which the part  46  of the surface having holes, or having boundaries defined by rows of holes, is a concave or curved surface, with the curvature being opposite the curvature of the rest of the surface of shell  12 . 
         [0046]    As is shown in the particular embodiment of  FIG. 6 , one line of holes  22  is radially spaced apart, by being separated by arc A, from another line of holes  22 . Also, these separate, axially or longitudinally extending lines are disposed in a staggered conformation, such that the centers of holes  22  in each line are not at the same axial position about the length of shell  12 . Instead, the centers of holes  22  of one line fall between the centers of holes of the separate line. In a preferred embodiment, the centers of one line of holes may, in the longitudinal direction, fall half-way between the centers of the separate line of holes. The hole diameters and hole spacing, as described above with respect to the embodiment comprising both inner and outer shells in  FIG. 1 , are appropriate with respect to the embodiment illustrated in  FIG. 6 . 
         [0047]    In the embodiment shown in  FIG. 6 , using a single elongated shell  12 , the outer diameter of this shell may be reduced relative to the outer diameter of an outer shell used in the two-shell configuration, for example in the embodiment illustrated in  FIG. 1 . In this case, a coupling  50  may be used, as shown in  FIG. 8 , to adapt the smaller diameter shell  12  to a larger diameter receptacle or pocket  55 . Coupling  50  therefore allows shell  12 , having a diameter that is smaller than a conventional applicator, to be maintained in a fixed position in bracketing used for pocket  55  for mounting such a conventional applicator. A representative receptacle or pocket  55  may be designed to accommodate a conventional shell having an outer diameter from about 25 mm to about 32 mm (about 1 inch to about 1.25 inches), whereas a single exemplary shell, for example in the embodiment illustrated in  FIGS. 6 and 7 , may have an outer diameter of only about 19 mm (about ¾ inches). Coupling  50  can therefore be used to occupy some of the excess space between pocket  55  and shell  12  and also maintain a fixed position of shell  12  relative to a polymer melt curtain during ozonation. 
         [0048]    Applicator bars described herein are suitable in polymer oxidation methods to improve the adhesion of a polymer to a substrate. According to such methods, a surface of the polymer (e.g., an essentially flat molten polymer extrudate) may be exposed to an ozone-containing gas discharged from any of the various applicators described above. 
         [0049]    According to the particular polymer oxidation method known as melt curtain ozonation, ozone-containing gas, formed as a mixture of ozone gas and a diluent gas such as air, is routed to an ozone applicator such as those described above. The ozone gas is first formed, at concentrations discussed above, in an ozone generator according to known methods. Aspects of the invention are directed to methods and associated equipment for ensuring that a gas such as a diluent gas flows through the applicator continually during the ozonation process, even when ozone gas flow is stopped or interrupted. For example, ozone gas flow may be diverted from applicator during startup, shutdown, and non-normal operating periods over the course of the ozonation process, such as those associated with operational upsets and/or unsafe conditions. Apparatuses and methods associated with these aspects therefore ensure that gas flows through applicator  10  during ozonation even in the absence of ozone gas flow. 
         [0050]    Accordingly, a representative flow configuration used in equipment such as in an ozonation apparatus for flowing gases to an ozone applicator is depicted in  FIG. 3 . An ozone conduit  30  is used to flow ozone gas from an ozone generator  35  to an ozone applicator, such as the representative applicator  10  depicted in  FIG. 1 . A device  32  is positioned on ozone gas conduit  30  and acts on the ozone gas stream to interrupt or stop flow to the ozone applicator when necessary, such as under any of the non-normal operating periods discussed above. Device  32  may, for example, be a diverter valve to route ozone gas to a vent conduit  34  rather than allowing ozone gas to continue, in the case of normal operation, through ozone gas conduit  30 . Device  32 , which may be an automatically or manually actuated valve, is positioned and acts on flow through ozone gas conduit  30  between ozone generator and ozone applicator  10 . 
         [0051]    In the flow configuration depicted in  FIG. 3 , diluent gas conduit  36  flows diluent gas such as air to ozone applicator  10 . As shown, diluent gas conduit  36  and ozone gas conduit  30  intersect or fluidly communicate, resulting in mixing of ozone gas and diluent gas to form ozone-containing gas in an ozone-containing gas conduit  38  upstream of applicator  10 . This intersection or mixing occurs downstream of device  32 , allowing diluent gas to be continually routed through applicator  10 , independently of ozone gas. The diluent gas may be fed to ozone gas conduit  30  through a jet pump (not shown) or other type of gas moving equipment. As discussed above, the flow of diluent gas may be increased or decreased when ozone gas flow is interrupted, depending on the desired mode of operation and the need to maintain positive pressure on a molten polymer film in the vicinity of applicator  10 . Importantly, the flow configuration allows continuous input of diluent gas through applicator  10 . 
         [0052]    Typical flow rates of ozone gas and diluent gas during normal operating periods range from 2.8 to 280 liters per minute (0.1 to 10 cubic feet per minute (CFM)), but vary significantly according to the particular application. Ratios of ozone gas: diluent gas flow rates often range from 1:10 to 10:1. Ozone applicators described above, which may have an inner shell disposed within an outer shell, or otherwise a single shell with a particular outlet opening configuration, improve gas distribution compared to conventional applicators, allowing for greater flexibility in processes involving gas distribution such as melt curtain ozonation. 
         [0053]    For example, the use of these ozone applicators allows comparatively higher gas flows through the applicator, without resulting in detrimentally high back pressure in the ozone generator, which typically operates at slightly above atmospheric pressure (e.g., from about 0.2 barg to about 0.7 barg (about 3 to about 10 psig)). In one representative embodiment, a flow of 57 liters per minute (2 CFM) of ozone-containing gas through a conventional applicator may result in excessive ozone generator pressures, whereas a flow of 85-113 liters per minute (3-4 CFM) is possible through applicators described above, without exceeding the ozone generator pressure thresholds. According to various embodiments of the invention, a pressure regulator (e.g., a pressure relief valve) may be included in an ozonation apparatus to prevent excessive ozone generator pressures. 
         [0054]    Additionally, ozone applicators described above provide improved gas distribution, for example across the width of a sheet of molten polymer, allowing for comparatively less air or other diluent to be charged to the applicator to achieve a desired degree of distribution (e.g., uniformity of oxidation of a molten polymer surface). Reduced diluent flow rates provide correspondingly increased ozone concentrations in ozone-containing gas discharged from the applicator and consequently improved oxidization of a polymer surface. Overall, therefore, a comparatively greater range of flow rates can be applied to applicators having (i) an inner and outer shell configuration with internal openings (e.g., elongated apertures or otherwise holes) and an outlet (e.g., in the form of a plurality of holes or otherwise an elongated slot), or otherwise (ii) a single shell configuration with a plurality of outlet openings as described above. Gas distribution is improved at low flow rates, while back pressure buildup is managed at high flow rates. 
         [0055]    Ozone applicators as described herein thus provide a number of possible advantages, particularly in melt curtain ozonation processes, such as higher laminate production rates and improved product quality in terms of reduced delamination or greater force needed to separate the polymer from the substrate (e.g., paper) in the finished product. In view of the above, it will be seen that other advantages may be achieved and other advantageous results may be obtained. It will also be appreciated that the apparatuses and methods described above may be used with, or performed in conjunction with, conventional apparatuses and methods, such as those used for corona pre-treatment or flame pretreatment. As various changes could be made in the above apparatuses and methods without departing from the scope of the present disclosure, it is intended that all matter contained in this application shall be interpreted as illustrative only and not limiting in any way the scope of the appended claims. 
         [0056]    The following examples are set forth as representative of the present invention. These examples are not to be construed as limiting the scope of the invention as these and other equivalent embodiments will be apparent in view of the present disclosure and appended claims. 
       EXAMPLES 
       [0057]    Various melt curtain ozonation studies were undertaken to compare the performance of an ozone applicator as described above and a conventional applicator. Overall testing conditions are summarized in Table 1 and specific operating parameters that were varied in each test are summarized in Tables 2A-2H. 
         [0000]    
       
         
               
               
               
             
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                 1 Roll 
                 1 Roll 
                 Ozone Applicator Bars (2) 
               
               
                 32,000 ft 
                 60,000 ft 
                   
               
               
                 4          -12 
                   
                   
               
               
                 P           
                 48            24CT PET 
                   
               
               
                 25           wide 
                 
                           
                 
                   
               
               
                 Makeready 
                   
                   
               
             
          
           
               
                 Materials Needed: 
               
               
                 Mica A131X Primer, NA-204 or NA-214 
               
               
                 XL LINE SET-UP 
               
               
                 Die gap = .030″ 
               
               
                 Nip Impression-½           
               
               
                 CAAAC Plug or other as only one XL            needed 
               
               
                            Temp-          F 
               
               
                 Die Temp at 500° F. and 610° F. on edges 
               
               
                             as specified 
               
               
                   
               
               
                             indicates data missing or illegible when filed 
               
             
          
         
       
     
         [0000]    
       
         
               
               
             
               
               
               
               
               
             
           
               
                   
                 TABLE 2A 
               
               
                   
                   
               
             
             
               
                   
                 Phase 1-Ozone Value Displayed v/s Voltage and Added Air 
               
               
                   
                 Use Makeready Film (No Primer) for Phase 1 
               
               
                   
                 Part 1: Ozone Monitor in Normal (Current) Position  
               
               
                   
                 (after added air B4 Applicator Bar) 
               
               
                   
                 Use current Applicator Bar 
               
               
                   
                 LDPE at Minimum coating weight and minimum           nespeed 
               
               
                   
                   
               
             
          
           
               
                   
                   
                   
                   
                 Record Displayed Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Ozone (g/Nm3) 
               
               
                   
                   
               
               
                   
                 1 
                 60 
                 0 
                   
               
               
                   
                 2 
                 70 
                 0 
                   
               
               
                   
                 3 
                 75 
                 0 
                   
               
               
                   
                 4 
                 80 
                 0 
                   
               
               
                   
                 5 
                 85 
                 0 
                   
               
               
                   
                 6 
                 90 
                 0 
                   
               
               
                   
                 7 
                 95 
                 0 
                   
               
               
                   
                 8 
                 100 
                 0 
                   
               
               
                   
                 9 
                 60 
                 1 
                   
               
               
                   
                 10 
                 70 
                 1 
                   
               
               
                   
                 11 
                 75 
                 1 
                   
               
               
                   
                 12 
                 80 
                 1 
                   
               
               
                   
                 13 
                 85 
                 1 
                   
               
               
                   
                 14 
                 90 
                 1 
                   
               
               
                   
                 15 
                 95 
                 1 
                   
               
               
                   
                 16 
                 100 
                 1 
                   
               
               
                   
                 17 
                 60 
                 2 
                   
               
               
                   
                 18 
                 70 
                 2 
                   
               
               
                   
                 19 
                 75 
                 2 
                   
               
               
                   
                 20 
                 80 
                 2 
                   
               
               
                   
                 21 
                 85 
                 2 
                   
               
               
                   
                 22 
                 90 
                 2 
                   
               
               
                   
                 23 
                 95 
                 2 
                   
               
               
                   
                 24 
                 100 
               
               
                   
                   
               
               
                   
                   
                   
                   
                 Record Ozone Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Displayed 
               
               
                   
                   
               
               
                   
                 25 
                 60 
                 3 
                   
               
               
                   
                 26 
                 70 
                 3 
                   
               
               
                   
                 27 
                 75 
                 3 
                   
               
               
                   
                 28 
                 80 
                 3 
                   
               
               
                   
                 29 
                 85 
                 3 
                   
               
               
                   
                 30 
                 90 
                 3 
                   
               
               
                   
                 31 
                 95 
                 3 
                   
               
               
                   
                 32 
                 100 
                 3 
               
               
                   
                   
               
               
                   
                             indicates data missing or illegible when filed 
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 2B 
               
               
                   
               
               
                 Part 2: Ozone Monitor Input at OP Side of Applicator Bar 
               
               
                 LDPE at Minimum coating weight and minimum linespeed 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                 Record Displayed Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Ozone (g/Nm3) 
               
               
                   
                   
               
               
                   
                 40 
                 60 
                 0 
                   
               
               
                   
                 41 
                 70 
                 0 
                   
               
               
                   
                 42 
                 75 
                 0 
                   
               
               
                   
                 43 
                 80 
                 0 
                   
               
               
                   
                 44 
                 85 
                 0 
                   
               
               
                   
                 45 
                 90 
                 0 
                   
               
               
                   
                 46 
                 95 
                 0 
                   
               
               
                   
                 47 
                 100 
                 0 
                   
               
               
                   
                 48 
                 60 
                 0 
                   
               
               
                   
                 49 
                 70 
                 0 
                   
               
               
                   
                 50 
                 75 
                 1 
                   
               
               
                   
                 51 
                 80 
                 1 
                   
               
               
                   
                 52 
                 85 
                 1 
                   
               
               
                   
                 53 
                 90 
                 1 
                   
               
               
                   
                 54 
                 95 
                 1 
                   
               
               
                   
                 55 
                 100 
                 1 
                   
               
               
                   
                 56 
                 60 
                 2 
                   
               
               
                   
                 57 
                 70 
                 2 
                   
               
               
                   
                 58 
                 75 
                 2 
                   
               
               
                   
                 59 
                 80 
                 2 
                   
               
               
                   
                 60 
                 85 
                 2 
                   
               
               
                   
                 61 
                 90 
                 2 
                   
               
               
                   
                 62 
                 95 
                 2 
                   
               
               
                   
                 63 
                 100 
                 2 
               
               
                   
                   
               
               
                   
                   
                   
                   
                 Record Ozone Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Displayed 
               
               
                   
                   
               
               
                   
                 64 
                 60 
                 3 
                   
               
               
                   
                 65 
                 70 
                 3 
                   
               
               
                   
                 66 
                 75 
                 3 
                   
               
               
                   
                 67 
                 80 
                 3 
                   
               
               
                   
                 68 
                 85 
                 3 
                   
               
               
                   
                 69 
                 90 
                 3 
                   
               
               
                   
                 70 
                 95 
                 3 
                   
               
               
                   
                 71 
                 100 
                 3 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 2C 
               
               
                   
               
               
                 Part 3: Ozone Monitor Input at OP Side of Conventional Applicator Bar 
               
               
                 LDPE at Minimum coating weight and minimum linespeed 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                 Record Displayed Value 
               
               
                 Variable 
                 %Voltage 
                 Added Air 
                 Ozone (g          ) 
               
               
                   
               
               
                 80 
                 60 
                 0 
                   
               
               
                 81 
                 70 
                 0 
                   
               
               
                 82 
                 75 
                 0 
                   
               
               
                 83 
                 80 
                 0 
                   
               
               
                 84 
                 85 
                 0 
                   
               
               
                 85 
                 90 
                 0 
                   
               
               
                 86 
                 95 
                 0 
                   
               
               
                 87 
                 100 
                 0 
                   
               
               
                 88 
                 60 
                 1 
                   
               
               
                 89 
                 70 
                 1 
                   
               
               
                 90 
                 75 
                 1 
                   
               
               
                 91 
                 80 
                 1 
                   
               
               
                 92 
                 85 
                 1 
                   
               
               
                 93 
                 90 
                 1 
                   
               
               
                 94 
                 95 
                 1 
                   
               
               
                 95 
                 100 
                 1 
                   
               
               
                 96 
                 60 
                 2 
                   
               
               
                 97 
                 70 
                 2 
                   
               
               
                 98 
                 75 
                 2 
                   
               
               
                 99 
                 80 
                 2 
                   
               
               
                 100 
                 85 
                 2 
                   
               
               
                 101 
                 90 
                 2 
                   
               
               
                 102 
                 95 
                 2 
                   
               
               
                 103 
                 100 
                 2 
               
               
                   
               
               
                   
                   
                   
                 Record Ozone Value 
               
               
                 Variable 
                 % Voltage 
                 Added Air 
                 Displayed 
               
               
                   
               
               
                 104 
                 60 
                 3 
                   
               
               
                 105 
                 70 
                 3 
                   
               
               
                 106 
                 75 
                 3 
                   
               
               
                 107 
                 80 
                 3 
                   
               
               
                 108 
                 85 
                 3 
                   
               
               
                 109 
                 90 
                 3 
                   
               
               
                 110 
                 95 
                 3 
                   
               
               
                 111 
                 100 
                 3 
               
               
                   
               
               
                             indicates data missing or illegible when filed 
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 2D 
               
               
                   
               
               
                 Part 4: Ozone Monitor Input at OP Side of Applicator 
               
               
                 Bar Design Slot Gap at .010″ edges, .007″ center 
               
               
                 LDPE at Minimum coating weight and minimum linespeed 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                 Record Displayed Value 
               
               
                   
                 Variable 
                 %Voltage 
                 Added Air 
                 Ozone (g/Nm3) 
               
               
                   
                   
               
               
                   
                 120 
                 60 
                 0 
                   
               
               
                   
                 121 
                 70 
                 0 
                   
               
               
                   
                 122 
                 75 
                 0 
                   
               
               
                   
                 123 
                 80 
                 0 
                   
               
               
                   
                 124 
                 85 
                 0 
                   
               
               
                   
                 125 
                 90 
                 0 
                   
               
               
                   
                 126 
                 95 
                 0 
                   
               
               
                   
                 127 
                 100 
                 0 
                   
               
               
                   
                 128 
                 60 
                 1 
                   
               
               
                   
                 129 
                 70 
                 1 
                   
               
               
                   
                 130 
                 75 
                 1 
                   
               
               
                   
                 131 
                 80 
                 1 
                   
               
               
                   
                 132 
                 85 
                 1 
                   
               
               
                   
                 133 
                 90 
                 1 
                   
               
               
                   
                 134 
                 95 
                 1 
                   
               
               
                   
                 135 
                 100 
                 1 
                   
               
               
                   
                 136 
                 60 
                 2 
                   
               
               
                   
                 137 
                 70 
                 2 
                   
               
               
                   
                 138 
                 75 
                 2 
                   
               
               
                   
                 139 
                 80 
                 2 
                   
               
               
                   
                 140 
                 85 
                 2 
                   
               
               
                   
                 141 
                 90 
                 2 
                   
               
               
                   
                 142 
                 95 
                 2 
                   
               
               
                   
                 143 
                 100 
                 2 
               
               
                   
                   
               
               
                   
                   
                   
                   
                 Record Ozone Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Adde dAir 
                 Displayed 
               
               
                   
                   
               
               
                   
                 144 
                 60 
                 3 
                   
               
               
                   
                 145 
                 70 
                 3 
                   
               
               
                   
                 146 
                 75 
                 3 
                   
               
               
                   
                 147 
                 80 
                 3 
                   
               
               
                   
                 148 
                 85 
                 3 
                   
               
               
                   
                 149 
                 90 
                 3 
                   
               
               
                   
                 150 
                 95 
                 3 
                   
               
               
                   
                 151 
                 100 
                 3 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 2E 
               
               
                   
               
               
                 Part 5: Ozone Monitor input at OP Feed with Applicator 
               
               
                 Bar (Dual Feed) Slot Gap at .010″ edge, .007″ center 
               
               
                 LDPE at Minimum coating weight and minimum linespeed 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                 Record Displayed Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Ozone (g/Nm3) 
               
               
                   
                   
               
               
                   
                 160 
                 60 
                 0 
                   
               
               
                   
                 161 
                 70 
                 0 
                   
               
               
                   
                 162 
                 75 
                 0 
                   
               
               
                   
                 163 
                 80 
                 0 
                   
               
               
                   
                 164 
                 85 
                 0 
                   
               
               
                   
                 165 
                 90 
                 0 
                   
               
               
                   
                 166 
                 95 
                 0 
                   
               
               
                   
                 167 
                 100 
                 0 
                   
               
               
                   
                 169 
                 60 
                 1 
                   
               
               
                   
                 169 
                 70 
                 1 
                   
               
               
                   
                 170 
                 75 
                 1 
                   
               
               
                   
                 171 
                 80 
                 1 
                   
               
               
                   
                 172 
                 85 
                 1 
                   
               
               
                   
                 173 
                 90 
                 1 
                   
               
               
                   
                 174 
                 95 
                 1 
                   
               
               
                   
                 175 
                 100 
                 1 
                   
               
               
                   
                 176 
                 60 
                 2 
                   
               
               
                   
                 177 
                 70 
                 2 
                   
               
               
                   
                 178 
                 75 
                 2 
                   
               
               
                   
                 179 
                 80 
                 2 
                   
               
               
                   
                 180 
                 85 
                 2 
                   
               
               
                   
                 181 
                 90 
                 2 
                   
               
               
                   
                 182 
                 95 
                 2 
                   
               
               
                   
                 183 
                 100 
                 2 
               
               
                   
                   
               
               
                   
                   
                   
                   
                 Record Ozone Value 
               
               
                   
                 Variable 
                 % Voltage 
                 Added Air 
                 Displayed 
               
               
                   
                   
               
               
                   
                 184 
                 60 
                 3 
                   
               
               
                   
                 185 
                 70 
                 3 
                   
               
               
                   
                 186 
                 75 
                 3 
                   
               
               
                   
                 187 
                 80 
                 3 
                   
               
               
                   
                 188 
                 85 
                 3 
                   
               
               
                   
                 189 
                 90 
                 3 
                   
               
               
                   
                 190 
                 95 
                 3 
                   
               
               
                   
                 191 
                 100 
                 3 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
             
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2F 
               
               
                   
               
             
             
               
                 Phase 2-Ozone/TIAG Adhesion 
                 Phase 2 
               
               
                 Structure-48 ga PET/PEI/15# LDPE (NA-214) 
                 Insert Slip Sheet labeled with Variable Number. 
               
               
                 NA214 Melt Temp-590 F. 
                 Save Sample labeled with OP Side for Aged Adhesion Testing. 
               
               
                 Die Temp at 590 F. and 595 F. on edges 
                   
               
               
                 Ozone at 35 psi, O2 = 80           , Added Air = 2           ,  
                   
               
               
                 Reactor Pressure = 4.5 
               
               
                   
               
             
          
           
               
                 Part 1: Ozone Monitor Input at OP Side of Conventional Applicator Bar 
               
             
          
           
               
                   
                   
                   
                 Record 
                   
                   
                 Off-line 
                 Aged 
               
               
                 Variable 
                 Linespeed 
                 Airgap 
                 Ozone Monitor (g/Nm3) 
                 Voltage (%) 
                 TIAG 
                 Adhesion 
                 Adhesion 
               
               
                   
               
               
                 200 
                 400 
                 9 
                   
                 0 
                 100 
                   
                   
               
               
                 201 
                 400 
                 8.2 
                   
                 0 
                 90 
                   
                   
               
               
                 202 
                 400 
                 7.4 
                   
                 0 
                 80 
                   
                   
               
               
                 203 
                 435 
                 7.1 
                   
                 0 
                 70 
                   
                   
               
               
                 204 
                 510 
                 7.1 
                   
                 0 
                 60 
                   
                   
               
               
                 205 
                 605 
                 7.1 
                   
                 0 
                 50 
                   
                   
               
               
                 206 
                 760 
                 7.1 
                   
                 0 
                 40 
                   
                   
               
               
                 207 
                 400 
                 9 
                   
                 70 
                 100 
                   
                   
               
               
                 208 
                 400 
                 8.2 
                   
                 70 
                 90 
                   
                   
               
               
                 209 
                 400 
                 7.4 
                   
                 70 
                 80 
                   
                   
               
               
                 210 
                 435 
                 7.1 
                   
                 70 
                 70 
                   
                   
               
               
                 211 
                 510 
                 7.1 
                   
                 70 
                 60 
                   
                   
               
               
                 212 
                 605 
                 7.1 
                   
                 70 
                 50 
                   
                   
               
               
                 213 
                 760 
                 7.1 
                   
                 70 
                 40 
                   
                   
               
               
                 214 
                 400 
                 9 
                   
                 80 
                 100 
                   
                   
               
               
                 215 
                 400 
                 8.2 
                   
                 80 
                 90 
                   
                   
               
               
                 216 
                 400 
                 7.4 
                   
                 80 
                 80 
                   
                   
               
               
                 217 
                 435 
                 7.1 
                   
                 80 
                 70 
                   
                   
               
               
                 218 
                 510 
                 7.1 
                   
                 80 
                 60 
                   
                   
               
               
                 219 
                 605 
                 7.1 
                   
                 80 
                 50 
                   
                   
               
               
                 220 
                 760 
                 7.1 
                   
                 80 
                 40 
                   
                   
               
               
                 221 
                 400 
                 9 
                   
                 90 
                 100 
                   
                   
               
               
                 222 
                 400 
                 8.2 
                   
                 90 
                 90 
                   
                   
               
               
                 223 
                 400 
                 7.4 
                   
                 90 
                 80 
                   
                   
               
               
                 224 
                 435 
                 7.1 
                   
                 90 
                 70 
                   
                   
               
               
                 225 
                 510 
                 7.1 
                   
                 90 
                 60 
                   
                   
               
               
                 226 
                 605 
                 7.1 
                   
                 90 
                 50 
                   
                   
               
               
                 227 
                 760 
                 7.1 
                   
                 90 
                 40 
                   
                   
               
               
                 228 
                 1010 
                 7.1 
                   
                 90 
                 30 
               
               
                   
               
               
                             indicates data missing or illegible when filed 
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2G 
               
             
             
               
                   
               
               
                 Part 2: Ozone Monitor Input at OP Feed with Applicator Bar (Dual Feed)  
               
               
                 Slot Gap at .010″ edge, .007″ center 
               
             
          
           
               
                   
                   
                   
                 Record 
                   
                   
                   
                   
               
               
                   
                   
                   
                 Ozone 
                   
                   
                   
                   
               
               
                   
                 Line- 
                   
                 Monitor 
                 Voltage 
                   
                 Off-line 
                 Aged 
               
               
                 Variable 
                 speed 
                 Airgap 
                 (g/Nm3) 
                 (%) 
                 TIAG 
                 Adhesion 
                 Adhesion 
               
               
                   
               
             
          
           
               
                 229 
                 400 
                 9 
                   
                 70 
                 100 
                   
                   
               
               
                 230 
                 400 
                 8.2 
                   
                 70 
                 90 
                   
                   
               
               
                 231 
                 400 
                 7.4 
                   
                 70 
                 80 
                   
                   
               
               
                 232 
                 435 
                 7.1 
                   
                 70 
                 70 
                   
                   
               
               
                 233 
                 510 
                 7.1 
                   
                 70 
                 60 
                   
                   
               
               
                 234 
                 605 
                 7.1 
                   
                 70 
                 50 
                   
                   
               
               
                 235 
                 760 
                 7.1 
                   
                 70 
                 40 
                   
                   
               
               
                 236 
                 400 
                 9 
                   
                 80 
                 100 
                   
                   
               
               
                 237 
                 400 
                 8.2 
                   
                 80 
                 90 
                   
                   
               
               
                 238 
                 400 
                 7.4 
                   
                 80 
                 80 
                   
                   
               
               
                 239 
                 435 
                 7.1 
                   
                 80 
                 70 
                   
                   
               
               
                 240 
                 510 
                 7.1 
                   
                 80 
                 60 
                   
                   
               
               
                 241 
                 605 
                 7.1 
                   
                 80 
                 50 
                   
                   
               
               
                 242 
                 760 
                 7.1 
                   
                 80 
                 40 
                   
                   
               
               
                 243 
                 400 
                 9 
                   
                 90 
                 100 
                   
                   
               
               
                 244 
                 400 
                 8.2 
                   
                 90 
                 90 
                   
                   
               
               
                 245 
                 400 
                 7.4 
                   
                 90 
                 80 
                   
                   
               
               
                 246 
                 435 
                 7.1 
                   
                 90 
                 70 
                   
                   
               
               
                 247 
                 510 
                 7.1 
                   
                 90 
                 60 
                   
                   
               
               
                 248 
                 605 
                 7.1 
                   
                 90 
                 50 
                   
                   
               
               
                 249 
                 760 
                 7.1 
                   
                 90 
                 40 
                   
                   
               
               
                 250 
                 1010 
                 7.1 
                   
                 90 
                 30 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2H 
               
             
             
               
                   
               
               
                 Part 3: Coating Weight/Minimum Ozone versus Adhesion 
               
               
                 Ozone Monitor input at OP Feed with Applicator Bar (Dual Feed)  
               
               
                 Slot Gap at .010″ edge, .007″ center 
               
             
          
           
               
                   
                   
                   
                 Record 
                   
                   
                   
                   
                   
               
               
                   
                   
                   
                 Ozone  
                   
                   
                   
                   
                   
               
               
                   
                   
                   
                 Monitor 
                 Voltage 
                 Coating 
                   
                 Off-line 
                 Aged 
               
               
                 Variable 
                 Linespeed 
                 Airgap 
                 (g/Nm3) 
                 (%) 
                 Weight 
                 TIAG 
                 Adhesion 
                 Adhesion 
               
               
                   
               
             
          
           
               
                 301 
                 510 
                 7.1 
                   
                 0 
                 10 
                 60 
                   
                   
               
               
                 302 
                 510 
                 7.1 
                   
                 70 
                 10 
                 60 
                   
                   
               
               
                 303 
                 605 
                 7.1 
                   
                 70 
                 10 
                 50 
                   
                   
               
               
                 304 
                 760 
                 7.1  
                   
                 70 
                 10 
                 40 
                   
                   
               
               
                 305 
                 510 
                 7.1 
                   
                 80 
                 10 
                 60 
                   
                   
               
               
                 306 
                 605 
                 7.1 
                   
                 80 
                 10 
                 50 
                   
                   
               
               
                 307 
                 760 
                 7.1 
                   
                 80 
                 10 
                 40 
                   
                   
               
               
                 308 
                 1010 
                 7.1 
                   
                 80 
                 10 
                 30 
                   
                   
               
               
                 309 
                 1010 
                 7.1 
                   
                 80 
                 15 
                 30 
                   
                   
               
               
                 310 
                 1010 
                 7.1 
                   
                 80 
                 10 
                 30