Improved plastic films

Abstract

The present invention provides a stretch film comprising, a base film comprising a stretchable polymer film material arranged in a plurality of columns; a multiplicity of holes in the base film arranged in a plurality of columns; wherein the plurality of columns of base film and the plurality of columns of holes extend along a longitudinal direction of the base film; wherein each column of holes is separated from each adjacent column of holes in a transverse direction of the base film by one or more columns of base film; wherein the base film has a plane oriented along the longitudinal and transverse directions of the film, and wherein the base film has a thickness t0; wherein each hole of the multiplicity of holes is reinforced with a respective reinforcing rim, wherein each rim comprises a localised accumulation of stretchable polymer film material which forms a continuous perimetric circuit around each respective hole, wherein each rim has a cross-section dened by an inner edge of the rim adjacent to each respective hole and an outer edge of the rim opposite the inner edge, wherein the cross-section of the rim has a width wr measured between the inner edge and the outer edge of the rim, and wherein the cross-section has a thickness tr measured at the thickest point of the rim; wherein tr / t0> 2; and wherein tr / wr is from 0.2 to 6. Methods for producing the film involving a quenching step after hole perforation, and uses of the film are also provided.

Description

IMPROVED PLASTIC FILMS Field of the Invention This invention relates to a stretch ^lm with high resistance to tearing, high strength, high air permeability and high elongation potential. In particular, the present inventionis directed to a perforated stretch ^lm whose perforations are reinforced with rimscomprising localised accumulations of ^lm material, each of which forms a completeperimetric circuit around each respective hole and each of which typically has an outeredge which is substantially perpendicular to the plane of the base ^lm. The result of this is that the tear resistance of the perforated ^lm is increased and is substantially similar in all directions when a load is applied: the response of each hole to deformation is substantially isotropic. This reinforcement achieves a perforated stretch ^lm with improved mechanical properties. Films according to the present invention may be silage ^lm, stretch ^lm, prestretched stretch ^lm, hood ^lm or mulch ^lm, and can be produced by known methods of extrusion or co-extrusion such as cast, blown and the like. In addition, the present invention is directed to obtaining a perforated ^lm as described above. Background of the Invention It is known in the art that perforated stretch ^lms are valuable tools for the flexible packaging of goods, and unitisation of loads on a pallet. In particular, perforated ^lmsare useful for the packaging of items requiring ventilation, such as flowers, certainbottled liquids, bales of straw or certain fruits. Several stretch ^lms for packaging applications have been previously described. EP0371080B1 discloses a stretch wrapping ^lm, comprising a primary stretch ^lm reinforced with a secondary stretch ^lm which is laminated onto the primary ^lm. Films of this type, when used to wrap palletised goods, are unable to provide adequate aeration to the goods within. It has been possible to achieve better aeration of palletised goods and increased ^lm strength when pulled in the main direction (MD: i.e. the longitudinal or machine direction) with stretch ^lms comprising a thin base ^lm, ventilation holes and longitudinal reinforcing elements. US2005 / 0118391A1 discloses a perforated reinforced stretch ^lm which has strips that extend in the MD and are attached to the base ^lm between the rows of holes, where2025.04.04 SPEC AS FILED 1242-10007WOthe strips prevent the propagation of tears. Parts of the strips extend sideways in the transverse direction (TD). The resulting ^lms are heavy, dif^cult to manufacture and susceptible to necking, with more material required to achieve a satisfactory coverage and grip on the goods. US2005 / 0123721A1 discloses a perforated stretch ^lm comprising prestretched reinforcement strips which are folded at least once, wherein the degree of reinforcement of the main ^lm, which is a blown or cast ^lm, is dictated either by the number of folds or by the number of columns of holes. EP0909721B1 discloses a perforated reinforced ^lm which can be extended longitudinally during use and has an adequate pulling strength, wherein longitudinal reinforcing elements are arranged at the non-perforated areas of the base ^lm. EP1768837B1 discloses a stretch ^lm comprising a base ^lm made of a stretchable plastic ^lm material and reinforcing strips, with a multiplicity of holes in the base ^lm arranged in several columns along a main direction. A lip is formed around each hole by an accumulation of plastic material from the base ^lm, but the reinforcement strips do not overlap the lips. EP820856A1 discloses a thin perforated prestretched ^lm where the perforations are made by thermal radiation without contacting the ^lm and occupy 30-70% of the surface of the ^lm. Material is accumulated and thereby forms a lip around each hole. US5935681 discloses an air permeable stretch ^lm formed by lamination. Perforations are formed in a ^lm using a hot pin to touch only the surface of the ^lm to locally melt the polymer material. The molten material then forms a perforation without direct mechanical intervention from the pin. A weld between the layers of the laminate is then formed. It is known in the art that perforated stretch ^lms inherently appear weaker than corresponding non-perforated stretch ^lms. Signi^cant effort has been directed through the years towards enhancing the mechanical properties of a perforated ^lm. The term “perforated stretch ^lm” as used herein does not include ^lm products in which slits or small punctures have already been introduced prior to use. The intention of such slits or punctures is that they largen (resulting in large openings) or break due to the ^lm being stretched during use in a wrapping machine with a prestretching system.2025.04.04 SPEC AS FILED 1242-10007WOIn particular, the present invention relates to signi^cantly reinforcing the holes in a perforated ^lm using accumulated plastic base ^lm material which forms a completeperimetric circuit of each respective hole. This reinforcement grants improvedmechanical properties to the ^lm as a whole. At present, it is relatively dif^cult in practice to obtain stretch ^lm perforations with balanced properties, such as resistance to tearing, in the longitudinal direction (also known as the Machine Direction, MD) and in the Transverse Direction (TD). This dif^culty arises from the impact of uniaxial orientation of the ^lm during its extrusion, since the ^lm is being processed in one direction (i.e. in the MD, being drawn away from the extruder), and during thermomechanical perforation where heat and tension are simultaneously applied to the ^lm. Thermomechanical action on the ^lm results in the development of thermal and physical stresses, such that the ^lm stretches in the MD and shrinks in the TD. Consequently, the holes deform and the propertiessuch as resistance to tearing become unbalanced in the MD and the TD respectively.The uniaxial orientation normally results in a ^lm with greater tear resistance in the MD compared to any other direction. This is especially true at the transverse-most points of a perforation (i.e. the antipodal points of a perforation which are closest to eithertransverse edge of the ^lm), as this is the area with the highest concentration of materialstress. This area is therefore weaker than other parts, and is hence more susceptible to tearing. The objective of the present invention is to overcome the problems mentioned above, providing a solution in the form of stretch ^lms featuring perforations whose perimetershave been reinforced with a rim with enhanced physical, tensile and tear resistanceproperties. Summary of the Invention In accordance with a ^rst aspect of the invention is provided a stretch ^lm comprising, a base ^lm (1) comprising a stretchable polymer ^lm material arranged in a plurality of columns; amultiplicity of holes (2) in the base ^lm arranged in a plurality of columns;wherein the plurality of columns of base ^lm and the plurality of columns of holes extend along a longitudinal direction of the base ^lm;2025.04.04 SPEC AS FILED 1242-10007WOwherein each column of holes is separated from each adjacent column of holesin a transverse direction of the base ^lm by one or more columns of base ^lm (6);wherein the base ^lm has a plane oriented along the longitudinal and transverse directions of the ^lm, wherein each hole of the multiplicity of holes is reinforced with a respectivereinforcing rim (3), wherein each rim comprises a localised accumulation of stretchablepolymer ^lm material which forms a continuous perimetric circuit around each respective hole, wherein each rim has a cross-section de^ned by an inner edge (4) ofthe rim adjacent to each respective hole and an outer edge (5) of the rim opposite theinner edge, wherein the cross-section of the rim has a width wr measured between the inner edge and the outer edge of the rim, and wherein the cross-section has a thickness trmeasured at the thickest point of the rim; wherein ^^ ^^^ > 2; and wherein^^^ ^^ is from 0.2 to 6.In accordance with a second aspect of the invention there is provided a method ofproducing a stretch ^lm according to the ^rst aspect of the invention, comprising providing an initial extruded stretch ^lm; perforating the initial stretch ^lm to form a base ^lm comprising a stretchable polymer ^lm material comprising columns of holes in the longitudinal direction, wherein each hole is separated from each adjacent hole in the transverse direction by at least one column of stretchable polymer ^lm material, wherein perforating the initial stretch ^lm is performed by using a thermal device, wherein a rim is formed by localised heating from the device; and applying to each formed rim a quenching means suf^cient to deliver localised quenching. In accordance with a third aspect of the invention there is provided a stretch ^lm obtainable from a process for producing a ^lm according to the second aspect of the invention. In accordance with a fourth aspect of the invention there is provided a use of a stretch ^lm according to the ^rst aspect of the invention or the ^lm obtainable according to the third aspect of the invention for packaging.2025.04.04 SPEC AS FILED 1242-10007WOThe optimised thermoplastic stretch ^lm of the present invention is particularly suitable for unitisation of goods, e.g. packages, bales, silage or plants bearing sharp edges. Itis also suitable for use in mulching, for example on arable land to suppress weeds andconserve water in crop production and landscaping. It is a bene^t of the invention that each reinforced rim is formed around and closer toeach hole than the conventional rims of the prior art which have much wider pro^les. Itis a further bene^t of the invention, that due to its con^guration (i.e. being taller andnarrower than the conventional rims), the rim withstands greater tensile and tearingforces along both the MD and TDs. As a result of this the improved ^lm of the inventionis able to be stretched without breaking when it is used to wrap goods on a pallet.Brief Description of the Drawings Further features and advantages of the reinforced stretch ^lm according to the present invention become apparent from the illustrative description of exemplary embodiments thereof taken in conjunction with the accompanying drawings. It is noted that the drawn ^gures are not drawn to scale and represent only schematic illustrations of systems. They do not represent the actual proportions of objects according to the present invention.Figure 1 shows some indicative sketches of a rim around a hole in a ^lm according tothe invention (1A) in comparison to a convention rim of the prior art (1B).Figures 2A and 2B show indicative sketches of a rim around a hole, indicating desirable(left) and undesirable (right) rim formation.Figures 3A and 3B show indicative sketches of ^lms according to the invention, whereinholes in adjacent columns are offset and rims are formed completely around each respective hole.Figure 4 shows an indicative cross section of a rim around a hole according to theinvention (^gure 4B) and according to prior art (^gure 4A). Moreover, ^gure 4 showshow critical parameters are measured from rim cross-sections.Detailed Description of the Invention2025.04.04 SPEC AS FILED 1242-10007WOIn accordance with a ^rst aspect of the invention is provided a stretch ^lm as de^nedabove.In one embodiment of the invention, the outer edge (5) of each rim (3) is substantiallyperpendicular to the plane of the base ^lm (as shown in ^gure 1, where the black line indicates the plane of the base ^lm, since in this indicative sketch no curvature isprovided in the ^lm). Accordingly, the outer edge of the rim meets the base ^lm atapproximately 90 degrees. In a different embodiment, the outer edge (5) of each rim(3) is not substantially perpendicular to the plane of the base ^lm.In an embodiment of the invention, each reinforcing rim (3) (hereafter called a ‘rim’, orinterchangeably a ‘lip’) comprises a substantially chemically homogeneous localised accumulation of stretchable polymer ^lm material. In other words, the stretchable polymer ^lm material in the base ^lm and in each rim is chemically homogeneous. The stretchable polymer ^lm material according to the invention typically comprises ULDPE, VLDPE, LLDPE, LDPE, m-LLDPE, MD-LLDPE, HDPE, PP, PP copolymers and other similar materials which are known in the art as suitable materials for plastic stretch^lms. In the invention, the complete perimetric circuit formed by each rim extendsaround the entirety of the circumference of each respective hole. In other words, eachcircuit can be seen as a boundary or loop encompassing the entire circumference ofeach respective hole (as seen in the left hand side of ^gures 2A and 2B). The left handside of ^gures 2A and 2B show two different rims according to the invention which havenon-uniform thickness around the continuous perimetric circuit. Figure 2A contains arim which has a larger width along the transverse direction (TD) of the ^lm. Figure 2Bcontains a rim which has a larger width along the machine direction (MD) of the ^lm.Figures 3A and 3B show ^lms which have columns of holes with rims as shown on the left hand side of ^gures 2A and 2B respectively. In an embodiment of the invention, the ratio of ^^^ ^^ is from 0.2 to 5, or from 0.2 to 4,or from 0.2 to 3, or from 0.2 to 2.5, or from 0.3 to 2, or from 0.5 to 2, or from 0.5 to 1.5, or from 0.5 to 1.3, or most preferably from 0.5 to 1.1. Unless stated, wr and tr are taken to be average measurements of width and thicknessof the rim both measured in the two main directions of the ^lm, the machine direction(MD) (also known as the longitudinal direction) and the transverse direction (TD).Methods for calculating these values for a stretch ^lm according to the invention areshown in the Examples and generally involve selecting 5 representative rims and taking2025.04.04 SPEC AS FILED 1242-10007WO5 measurements in the MD and TD respectively, calculating the mean average valuesin the TD and MD and then calculating the mean average of the TD and MD values togive the overall average value for the rims and ^lm as a whole. Alternatively, all of therims in a sample of ^lm can be measured and the average calculated as above. Generally, the use of controlled quenching to form the rims in this invention results in a variation in the width and thickness of the rim around the circumference of each respective hole, i.e. wr (TD) and wr (MD) are different, and tr (TD) and tr (MD) aredifferent from each other. This contrasts with the rims formed in EP0820856, which aregenerally uniform in this respect as outlined in paragraph

[0012] of EP0820856.The wr is generally the greatest extension of the rim between the inner edge and theouter edge of the rim, measured in a direction parallel to the plane of the base ^lm. The thickness tris measured at the thickest portion of the rim in a direction perpendicular to the plane of the base ^lm, and includes the thickness of the base ^lm directly below it.The value of t0 is an average thickness of the base ^lm. It can be calculated by taking5 measurements of the thickness of the base ^lm at locations away from the rim andthen calculating the mean average of these 5 values.In one embodiment the rim may have multiple protrusions in the vertical dimension perpendicular to the plane of the base ^lm. When measuring tr the largest of these vertical protrusions is selected. In a preferred embodiment of the invention the average tr is measured separately in the MD and the TD directions of the ^lm, and then the ratio of the average tr measured inthe MD divided by the average tr measured in the TD, trMD / trTD, is from 0.3 to 2.5, orfrom 0.5 to 2.5, or from 0.8 to 2.5, or from 0.9 to 2.5, and is most preferably from 0.9 to 1.6. It is understood that wr and tr can be measured using tools and methods and known to the skilled person. For example, these measurements can be made using SEM or digitalmicroscopy and pro^lometry.In an embodiment of the invention, when measured in the MD the ratio of wr to tr is from 1:0.15 to 1:2, or from 1:015 to 1:16, or from 1:0.17 to 1:1.6, or from 1:0.5 to 1:1. In an embodiment of the invention, when measured in the TD the ratio of t^^ w^ is from 0.2 to5, or from 0.2 to 4, or from 0.2 to 3, or from 0.2 to 2.5, or from 0.3 to 2, or from 0.5 to2025.04.04 SPEC AS FILED 1242-10007WO2, or from 0.5 to 1.5, or from 0.5 to 1.3, or most preferably from 0.5 to 1.1. The skilledperson is aware that properties in the MD and properties in the TD can be averaged togive a property reflective of the overall ^lm in use.In an embodiment of the invention the width wr is from 0.02 to 1.0 mm, optionally from0.02 to 0.8 mm, optionally from 0.02 to 0.6 mm, optionally from 0.03 to 0.6 mm,optionally from 0.03 to 0.5 mm, optionally from 0.03 to 0.45 mm, optionally from 0.03to 0.4 mm. The thickness of the accumulated material, tr, may be lower than 2.5 mm, lower than 2mm, lower than 1.5 mm, lower than 1 mm, lower than 0.5 mm, lower than 0.3 mm, lowerthan 0.25 mm, lower than 0.15 mm, lower than 0.1 mm, lower than 0.05 mm.In an embodiment of the invention the base ^lm has average thickness t0, and tr isthicker than t0by 2 to 25 times, or from 2 to 20 times, or from 2 to 18 times, or from 2 to 15 times, or from 2 to 14 times, or from 2 to 13 times, or from 3.5 to 13 times, ormost preferably from 4 to 13 times. It is understood that t0 is broadly constant acrossthe base ^lm. In an embodiment of the invention, the width wrcomprises two portions w1and w2, wherein w1 is a width between the inner edge of the rim and the thickest point of the rim, wherein w2is a width between the thickest point of the rim and the outer edge ofthe rim, wherein ^^ + ^^ = ^^ , and wherein^^^ ^^ is from 0.25 to 3.5, preferably from0.35 to 3, preferably from 0.35 to 2.5, preferably from 0.35 to 2, preferably from 0.45 to 2, preferably from 0.45 to 1.6, preferably from 0.45 to 1.4, preferably from 0.45 to 1.3, most preferably from 0.45 to 1.2. Preferably, in this embodiment, ^^^ ^^ is from 0.45 to 3.5, and / or wherein^^^ ^^ is from0.45 to 3.5, preferably ^^^ ^^ is from 0.45 to 3 and / or wherein^^^ ^^ is from 0.45 to 3,preferably ^^^ ^^^^ is from 0.45 to 2.5 and / or wherein ^ ^^ is from 0.45 to 2.5, preferably^^^ ^^ is from 0.5 to 2.5, and / or wherein^^^ ^^ is from 0.5 to 2.5, preferably^^^ ^^ is from0.7 to 2.5, and / or wherein ^^^ ^^ is from 0.7 to 2.5, preferably^^^ ^^ is from 0.85 to 2,and / or wherein ^^^ ^^ is from 0.85 to 2, preferably^^^ ^^ is from 0.9 to 2, and / or wherein^^^ ^^ is from 0.9 to 2.2025.04.04 SPEC AS FILED 1242-10007WOIn an embodiment of the invention, each rim is present only on one side of the base ^lm. In other words, rims are absent from one side of the entire base ^lm.In an embodiment of the invention each rim extends perpendicularly to the plane of thebase ^lm through each respective hole and comprises a further localised accumulationof stretchable polymer ^lm material on the opposite face of the base ^lm, such that therim is present on both faces of the base ^lm around each respective hole.In an embodiment of the invention each rim has substantially similar cross-section onboth faces of the base ^lm.In an embodiment of the invention the width wr on opposing faces of the base ^lmdiffers by no more than 10%, by no more than 9%, by no more than 8%, by no more than 7%, by no more than 6% or by no more than 5%. In a preferred embodiment, the width wron opposing faces of the base ^lm differs by no more than 5%.In an embodiment of the invention the thickness tr on opposing faces of the base ^lmdiffers by no more than 10%, by no more than 9%, by no more than 8%, by no more than 7%, by no more than 6% or by no more than 5%. In a preferred embodiment, the thickness tron opposing faces of the base ^lm differs by no more than 5%.In an embodiment of the invention each rim is substantially symmetrical above andbelow the plane of the base ^lm. In other words, when viewing along the plane of thebase ^lm which acts as a plane of symmetry, the accumulations on either side of the ^lm are substantially symmetrical (i.e. they appear substantially reflected across the plane of the base ^lm). In an embodiment of the invention each rim has substantially non-uniform width around the continuous perimetric circuit, and / or each rim has substantially non-uniformthickness around the continuous perimetric circuit. This arises due to the quenchingstep.In an embodiment of the invention each rim has substantially uniform width and / orthickness around the continuous perimetric circuit. In other words, the width and / orthickness of each rim will be substantially similar at all points around the circumferenceof the rim.2025.04.04 SPEC AS FILED 1242-10007WOIn an embodiment of the invention each rim has greatest thickness immediatelyadjacent to each respective hole. In a preferred embodiment, each rim has greatestthickness towards the centre of its width, i.e. at or around the point of wr / 2. The cross-section of the rim may resemble any shape, for example a circle, semicircle,oval, semioval, square, rectangle and so on. Alternatively, this concept can beexpressed by viewing the rim as a conical, spherical, or any other polyhedral frustumprojecting out of the plane of the base ^lm. In an alternative embodiment the rim hasits greatest thickness around the central point of its width, i.e. at or around wr / 2.In an embodiment of the invention each rim is preserved during stretching of the ^lmup to at least the yield point of the ^lm. This means that during the application of the^lm to a pallet, each rim remains present after its elongation, to ensure the optimummaterial utilization. By present in this context is meant that the rim retains its form asan accumulation of plastic material in a continuous perimetric boundary. In other words, a ^lm whose rims are damaged during elongation such that the continuous perimetric boundary is interrupted (i.e. no longer a full boundary around each hole) prior toreaching the yield point of the ^lm, would not accord with this embodiment. Elongationas referred to in this embodiment can be in the machine direction, the transversedirection or in any direction in between. The thickness and width of the rims will bereduced during such stretching.In an embodiment of the invention the ^lm exhibits minimal neck-in during applicationto palletised goods. In an embodiment of the invention, the adjacent columns of holes are parallel. In a different embodiment of the invention, the adjacent columns of holes are staggered.In an embodiment of the invention the ^lm further comprises one or more reinforcingelements disposed along the columns of base ^lm. These reinforcing elements areaf^xed to the base ^lm between adjacent columns of holes and are longitudinally oriented. In an embodiment the ^lm comprises one reinforcing element af^xed to the base ^lm between adjacent columns of holes. Preferably, all reinforcing elements, when present, are substantially aligned (alternatively termed “parallel”). 2025.04.04 SPEC AS FILED 1242-10007WOSuch a reinforcing element is made of a stretchable plastic ^lm material and is arranged on and af^xed to the base ^lm in an area between two adjacent columns of holes. In anembodiment, the reinforcing elements are longitudinally oriented. As described above,the reinforcing elements, which may be different material than the base ^lm, may be ^xed onto the base ^lm in order to reinforce the product during its application. The lateral edges on each side of the base ^lm may be hemmed together. This hemming of the lateral edges of the stretch ^lm provides additional reinforcement and prevents tearing at the edges of the ^lm. The presence of a reinforcing strip, while optional, can provide additional resistance to tearing. In effect, reinforcing strips act as a series of barriers to tear propagation through the base ^lm material, preventing runaway tearing from occurring without any additional force being applied. The reinforcing elements may not overlap the edges of any hole nor the rims surrounding these holes. In another embodiment, the reinforcing elements maycompletely or partially overlap the edges of any hole and / or the rims surrounding theseholes. Where reinforcing strips are present according to the invention, it is important that they do not overlap the edge of any holes, nor the rims surrounding these holes. Were any reinforcing strips overlap a hole, the resistance to tearing afforded by the strip is considerably reduced. That said, optimal overall ^lm properties can be achieved by placing strips as close as possible to, but not overlapping with, the rims surrounding the holes, such that the areas of solely base ^lm are minimised.In the invention, each rim has a cross-section de^ned by an inner edge of the rimadjacent to each respective hole and an outer edge of the rim opposite the inner edge. In other words, the cross-section is taken such that it is assessed in the same orientation as the plane of the base ^lm. In this context, the inner edge of each rim is the lateral edge (with respect to the plane of the base ^lm) closest to the perforation in the ^lm, and the outer edge of each rim is that which is opposite to the inner edge. It is understood that the ^lm can be bent between different holes, such that the plane of the base ^lm differs between holes and hence respective rims. It is understood that reference to the plane of the base ^lm in the context of a single hole and rim applies to the plane of the base ^lm at that location on the base ^lm. In other words, terms like “perpendicular to” and “parallel with” are assessed in the context of the ^lm in the immediate vicinity of the hole in question. 2025.04.04 SPEC AS FILED 1242-10007WOIn the invention, it is critical that each rim is properly formed such that it forms a complete perimetric boundary around each respective hole. If the rim is improperly formed, e.g. if it forms only a ‘bead’ on one side of the hole, then the bene^ts of the invention are not achieved. As illustrated in ^gure 1A, rims of the invention are taller and narrower than those ofthe prior art illustrated in ^gure 1B. In other words, rims of this invention ful^l the ratiorequirements ^^ ^^^ > 2; and wherein^^^ ^^ is from 0.2 to 6. Cross sections of the rimsaccording to the invention generally display a substantially perpendicular outer edge with respect to the plane of the base ^lm, whereas those of the prior art display a much more shallow gradient between the inner and outer edges. In accordance with a second aspect of the invention there is provided a method for producing a stretch ^lm according to the ^rst aspect of the invention, comprising: providing an initial extruded plastic stretch ^lm; perforating the initial plastic stretch ^lm to form a plastic stretch ^lm comprising a stretchable polymer ^lm material comprising columns of holes in the longitudinal direction, wherein each hole is separated from each adjacent hole in the transverse direction by at least one column of stretchable polymer ^lm material, wherein perforating the initial plastic stretch ^lm is performed by using a thermal device, wherein a rim is formed by localised heating from the device; applying to each formed rim a quenching means suf^cient to deliver localisedquenching. The thermal device provides heat to the ^lm which melts the stretchable polymer ^lm material and results in the formation of a hole. When the polymer ^lm material is hot it tends to move away from the vicinity of the newly formed hole. The application of rapid quenching in this invention enables the formation of a rim which is distinct from thosein the prior art. Rapid quenching stops this transfer of plastic material and causes rapidsolidi^cation in the vicinity of the hole, resulting in the majority of the mass of the rimbeing close to the hole. As explained above, rims of the prior art tend to be more spreadout, i.e. wider, with a more gradual gradient between their thickest point and the endpoint, i.e. widest point of the rim. This is due to slower cooling of the plastic material after the hole is formed. 2025.04.04 SPEC AS FILED 1242-10007WORims formed in this invention, made using the controlled use of quenching as detailed above, are continuous (that is, form a circuit around the rim without any breaks). The thickness tr and width wr of the rims may, however, vary in the different directions of the ^lm. The values may, for instance, vary in the MD and TD directions of the ^lm.In an embodiment of the invention the quenching means deliver a cooling rate of atleast 1°C · s-1, or at least 10°C · s-1, or at least 15°C · s-1, or at least 20 °C · s-1, or at least 25°C · s-1, at least 50°C · s-1, at least 70°C · s-1, at least 100°C · s-1, at least 150°C · s-1, at least 200°C · s-1, at least 300°C · s-1, or at least 350°C · s-1, or at least 400°C · s-1, or at least 450°C · s-1, or at least 500°C · s-1, or at least 550°C · s-1, or at least 600°C · s-1, orat least 650°C · s-1, or at least 700°C · s-1, or at least 750°C · s-1, or up to 800°C · s-1.In a preferred embodiment of the invention the quenching means deliver a cooling ratein any one of the following ranges (all values given in units of °C · s-1): 1 to 800, 2 to800, 2 to 750, 2 to 700, 2 to 650, 2 to 600, 2 to 500, 2 to 450, 2 to 400, 2 to 350, 2 to300, 2 to 250, 2 to 200 and 2 to 150.In an embodiment of the invention the quenching means achieve a reduction intemperature in each rim of at least 70°C, or at least 90°C, or at least 100°C, or at least200°C, or at least 250°C, or at least 300°C, or at least 350°C, or at least 400°C.In a preferred embodiment of the invention the quenching means achieve a reductionin temperature in each rim of any one of the following ranges (all values given in unitsof °C): 60 to 400, 70 to 400, 75 to 400, 75 to 380, 75 to 370 and 75 to 350.In an embodiment of the invention the temperature of each rim is reduced to below50°C, or to below 40°C, or to below 35°C, or to below 30°C, or to below 25°C, or to below 20°C, or to below 10°C, or to below 4°C, or to below 0°C, or to below -10°C, or preferably to below -20°C, most preferably to below -30°C.In an embodiment of the invention the quenching means are applied for a duration offrom 0.5 to 30 seconds, 0.6 to 20 seconds, preferably from 0.8 to 10 seconds, mostpreferably from 1 to 5 seconds.In an embodiment of the invention the quenching means are applied immediately afterthe formation of each rim. It is understood that immediately indicates that the quenching should be applied as soon as practically possible after perforation, and that no other steps are to take place between perforation and quenching. In an embodiment of theinvention the quenching means are applied between 0.5 and 60 seconds after2025.04.04 SPEC AS FILED 1242-10007WOperforation, between 0.5 and 30 seconds after perforation, preferably between 0.5 and 10 seconds after perforation. It is understood by the skilled person that the cooling rate and duration of cooling must be selected based on the temperature to which the ^lm is heated in order to perforate it, and that said selections achieve a cooling result in accordance with scienti^c laws (e.g. the skilled person does not choose a cooling rate and duration which reduces the temperature to absolute zero). Determination of cooling rates and durations is within the routine abilities of the skilled person. In an embodiment of the invention perforation is performed using a non-contact thermal radiation method, as described in EP0820856.In an embodiment of the invention, after perforation the ^lm is quenched, the quenchingmeans delivering cooling by convection, radiation or conduction, preferably by conduction. In accordance with a third aspect of the invention there is provided a stretch ^lm obtainable from a process for producing a ^lm according to the second aspect of the invention. In a preferred embodiment of the invention the method is for producing a stretch ^lm that exhibits minimal neck-in during application to palletised goods. In a further preferred embodiment the method is for producing a stretch ^lm with a rim that resists tearing. In accordance with a third aspect of the invention is provided a stretch ^lm obtainable by the method according to the second aspect of the invention. In accordance with a fourth aspect of the invention is provided the use of a stretch ^lm according to the ^rst or third aspects of the invention for packaging. In an embodiment, the packaging is applied for unitising goods. In an embodiment, the packaging is applied to silage, for example in the wrapping of bales. Another preferred embodiment of the invention has only the lateral edges of the base ^lm hemmed, without the corresponding reinforcement elements. The hemming of the lateral edges of the base ^lm also provides reinforcement at the edges of the ^lm. In an embodiment of the invention each hole is separated from an adjacent hole in the longitudinal direction by a spacer of base ^lm material. The spacers can be selectively 2025.04.04 SPEC AS FILED 1242-10007WOstretched in the TD by an amount which does not exceed the elongation at the breaking point of the spacer. All preferred embodiments and features according to the present invention should be considered as disclosed in combination with other preferred embodiments and features of the invention. In this invention, the main direction (MD) refers to the longitudinal direction of the ^lm; and the transverse direction (TD) refers to the direction of the ^lm perpendicular to this,i.e. across the width of the ^lm. The main direction is also known as the machinedirection, since this is the direction in which the ^lm moves through machinery during production: this term is well understood in the art. It may also be de^ned as the longitudinal direction. The term “prestretched” denotes that a stretching process has taken place during production of the thermoplastic ^lm and before the ^lm is used, for instance to package goods. Suitable properties for the ^lm of the invention are as follows. The ^lm preferably has a width of more than 250 mm, preferably more than 350 mm, even more preferably more than 400 mm. In an embodiment, the width of the ^lm is from 400 to 1300 mm, preferably from 400 to 700 mm or from 400 to 600 mm, or 450 to 550 mm, and more preferably is about 490 mm.In an embodiment, the ^lm of the invention has a necked-in width of 350-540 mm,preferably 440-520 mm and is most preferably around 500 mm, measured at the NDRpoint. The ^lm width decreases due to ^lm stretching, and this is known as "neck-in"effect. In the present invention, the term "necked-in" means that the "^nal" ^lm widthhas been obtained. The ^nal (after the production process) ^lm’s width is the "necked-in" width of the ^lm.In an embodiment, the base ^lm is substantially a thin ^lm, the average thickness of thebase ^lm t0 is from 4 to 110 µm, preferably from 5 to 50 µm, preferably 6 to 30 μm,preferably from 7 to 25 µm, most preferably 8 to 22 µm. The base ^lm is generally ofsubstantially uniform thickness, apart from in the regions of the rims. The base ^lm is preferably flat, i.e. there are no regions of wrinkling or folding, except where the rimsare. In other words, the thickness of the base ^lm in the columns is generally ofsubstantially uniform thickness. This means that the base ^lm in these regions does not 2025.04.04 SPEC AS FILED 1242-10007WOvary by more than 20%, preferably by no more than 15%, 10%, 5%, 3% or 2%. The base ^lm can alternatively be referred to as “homogeneous”. This feature distinguishes the ^lm of the invention from that disclosed previously, for instance, in references which disclose folding of the base ^lm. Such folding can result in wrinkles which for example result in poor point of attachment between the base ^lm and the reinforcing elements. This can lead to detachment of the reinforcing elements during stretching of the ^lm, which reduces the ^lm’s strength and leads to unpredictable behaviour. This is avoided by use of the base ^lm of substantially uniform thickness in the present invention. In an embodiment, the weight per square metre of the ^lm of the invention is less than 100 g / m2, preferably less than 60 g / m2, more preferably less than 45 g / m2, even morepreferably less than 43 g / m2 and most preferably less than 28 g / m2. In an embodiment,the weight per square metre of the ^lm of the invention is less than 42 g / m2, preferably less than 38 g / m2, more preferably less than 35 g / m2, and most preferably less than 32 g / m2. In another embodiment, the weight per square metre of the ^lm of the inventionis less than 30 g / m2, and more preferably less than 25 g / m2, less than 22 g / m2, less than20 g / m2, less than 17 g / m2, less than 15 g / m2, less than 12 g / m2 and most preferablyless than 10 g / m2. In an embodiment the holes cover less than 80% of the total surface area of the ^lm. In an embodiment the holes cover less than 70%, or preferably less than 60%, most preferably less than 50% of the total surface area of the ^lm. Preferably the holes cover less than 50% of the total surface area of the ^lm.In one embodiment, the ^lm is typically perforated and stretched so as to produce theprestretched stretch ^lm. In speci^c embodiments the ^lm is stretched after theformation of the perforations so as to produce the prestretched stretch ^lm of thepresent invention. Prestretching of the ^lm according to the invention does not stretch the rims beyond their yield point, i.e. the rims continue to exhibit elastic behaviour throughout and after the prestretching process.In preferred embodiments said ^lm is produced having a thickness of less than 23 μmwherein after the formation of perforations said ^lm is stretched and elongated lessthan 350% at a temperature range between room temperature and 100°C, so as toproduce the prestretched stretch ^lm of the present invention.In an embodiment, one surface of the ^lm comprises a cling surface. In an embodiment, two surfaces of the ^lm comprise a cling surface. Preferably, one surface comprises a 2025.04.04 SPEC AS FILED 1242-10007WOcling surface. Preferably, the cling surface is arranged in use such that it is in contact with the goods to be wrapped. Such a cling surface provides additional tack to the ^lm, enhancing the gripping of the ^lm and its holding force. Preferably, the reinforced thermoplastic ^lm of the present invention comprises a base ^lm which is an extruded multi-layered stretchable or prestretched ^lm. Preferably, the reinforced thermoplastic ^lm of the present invention comprises a base ^lm which is an extruded multilayered stretchable or pre-stretched ^lm. The base ^lm may have 3+2m layers, where m is a natural number such as 0, 1, 2, 3, 4... Preferably, the base ^lm has 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25 or 27 layers, more preferably 3, 5 or 7 layers, more preferably 3 or 5 layers, most preferably 5 layers. Preferably, the base ^lm has a symmetrical (ABA for a three layer ^lm; ABCBA for a ^ve layer ^lm) structure, wherein each of A, B and C represent a different type of layer in the multi-layer ^lm. Preferably the stack of the multilayer is symmetric with regards to the central layer.A further preferred base ^lm is one having a ^ve layer asymmetric structure (forexample ABCDE), wherein each of A, B, C, D and E represent a different type of layer in the ^lm. In the ABCDE structure, layers B and D may be made of the same composition and / or be of the same thickness. A further preferred base ^lm is one having a three layer asymmetric structure (for example ABC), wherein each of A, B and C represent a different type of layer in the ^lm. For the above ABA layer structure, the layer A is preferably present in the range of 5- 30% of the base ^lm thickness, preferably 5-20%, preferably 10-15% thereof. The layer B is preferably present in the range of 40-90% of the base total ^lm thickness, preferably 60-90%, preferably 70-80% thereof. For the above ABC layer structure, the layer A is preferably present in the range of 5- 30% of the base ^lm thickness, preferably 5-20%, preferably 10-15% thereof. The layer B is preferably present in the range of 40-90% of the base total ^lm thickness, preferably 60-90%, preferably 70-80% thereof. The layer C is preferably present in the range of 5-30% of the base total ^lm thickness, preferably 5-20%, preferably 10-15% thereof. 2025.04.04 SPEC AS FILED 1242-10007WOFor the above ABC layer structure, the layer A is preferably a slip layer, the layer B is preferably a core layer and the layer C is preferably a cling layer. For the above ABA layer structure, preferably the density of layer B > layer A. For the above ABC layer structure, preferably the density of layer A > layer C. For the above ABC layer structure, preferably the major melting peak point of layer A > layer C. For the above ABC layer structure, preferably the density of layer A > layer B > layer C. For the above ABC layer structure, preferably the major melting peak of layer A > layer B > layer C. For the above ABC layer structure, preferably the density of layer A is greater than 0.916 g / cm3, the density of layer B is preferably in the range of 0.916-0.938 g / cm3, and the density of layer C is preferably in the range of 0.870g / cm3to 0.905g / cm3. For the above ABC layer structure, preferably layer A comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%, preferably greater than 90%, preferably substantially 100% LLDPE. Preferably, the LLDPE of layer A, and where other materials to LLDPE are present, layer A itself, has a density of greater than 0.916 g / cm3, preferably 0.916-0.938 g / cm3, preferably about 0.923 g / cm3. Preferably, the LLDPE of layer A, and where other materials to LLDPE are present, layer A itself has a major melting peak in the range of 95°C-145°C, preferably 105°C-130°C, more preferably about 120°C. For the above ABC layer structure, preferably layer B comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%, preferably greater than 90%, preferably substantially 100% LLDPE. Preferably, the LLDPE of layer B, and where other materials to LLDPE are present, layer B itself has adensity in the range of 0.916-0.938 g / cm3, preferably 0.918-0.922 g / cm3, preferablyabout 0.920 g / cm3. Preferably, the LLDPE of layer B, and where other materials to LLDPE are present, layer B itself has a major melting peak in the range of 90°C-130°C, preferably 95°C-125°C, more preferably about 117°C. For the above ABC layer structure, preferably layer C comprises greater than 20% by weight of VLDPE or ULDPE (Very Low Density Polyethylene or Ultra Low Density Polyethylene), or a mixture thereof, preferably greater than 50%, preferably greater than 75%, preferably substantially 100% VLDPE or ULDPE. Most preferably, layer C comprises ULDPE. Preferably, the ULDPE of layer C, and where other materials to ULDPE are present, layer C itself has a density in the range of 0.870g / cm3to 2025.04.04 SPEC AS FILED 1242-10007WO0.890g / cm3, preferably 0.875-0.885 g / cm3, preferably about 0.880 g / cm3. Preferably, the VLDPE of layer C, and where other materials to VLDPE are present, layer C itself has a density in the range of 0.875g / cm3to 0.905g / cm3, preferably 0.900-0.905 g / cm3, preferably about 0.902 g / cm3. Preferably, the VLDPE of layer C, and where other materials to VLDPE are present, layer C itself has a major melting peak in the range of 70°C-130°C, preferably 80°C-125°C, more preferably about 100°C. Preferably, the ULDPE of layer C, and where other materials to ULDPE are present, layer C itself has a major melting peak in the range of 50°C-110°C, preferably 60°C-100°C, more preferably about 70°C. The cling properties can be increased by increasing the percentage of ULDPE in the cling layer. For the above ABCDE layer structure or the ABCDA structure or the ABCBE structure or the ABCBA structure, the layer A is preferably present in the range of 2-30% of the base ^lm thickness, preferably 5-15% thereof. The layer B is preferably present in the range of 5-40% of the base ^lmthickness, preferably 10-30% thereof. The layer C is preferably present in the range of20-80% of the base ^lm thickness, preferably 30-60% thereof, more preferably 35-55% thereof. The layer D (where present) is preferably present in the range of 5-40% of the base ^lm thickness, preferably 10-30% thereof. The layer E (where present) is preferably present in the range of 2-30% of the base ^lm thickness, preferably 5-15% thereof. For the above ABCDE layer structure, the layer A is preferably a slip layer, the layer B is preferably an intermediate layer and the layer C is preferably a core layer, layer D is an intermediate layer and layer E is preferably a cling layer. Preferably, the ULDPE oflayer E, and where other materials to ULDPE are present, layer E itself has a majormelting peak in the range of 50°C-110°C, preferably 60°C-100°C, more preferably about 70°C. The cling properties can be increased by increasing the percentage of ULDPE in the cling layer. For the above ABCDE layer structure, preferably the density of layer A > layer E. For the above ABCDE layer structure, preferably the major melting peak of layer A > layer E. For the above ABCDE layer structure, preferably the density of layer A > layer C > layer E. For the above ABCDE layer structure, preferably the major melting peak of layer A > layer C > layer E. For the above ABCDE layer structure, layer A preferably has a density in the range of 0.916-0.938 g / cm3, layer B preferably has a density of greater than 0.916 g / cm3, layer C preferably has a density of greater than 0.916 g / cm3, layer D preferably has a density 2025.04.04 SPEC AS FILED 1242-10007WOof greater than 0.916 g / cm3, layer E preferably has a density in the range of 0.870g / cm3to 0.905g / cm3. For the above ABCDE layer structure, preferably layer A comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%, preferably greater than 90%, preferably substantially 100% LLDPE. Preferably, the LLDPE of layer A, and where other materials to LLDPE are present, layer A itself has a density of greater than 0.916 g / cm3, preferably 0.916-0.938 g / cm3, preferably about 0.923 g / cm3. Preferably, the LLDPE of layer A, and where other materials to LLDPE are present, layer A itself has a major melting peak in the range of 95°C-145°C, preferably 105°C-130°C, more preferably about 120°C. For the above ABCDE layer structure, preferably layer B may be any polyole^n, preferably a polyethylene, and preferably comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%, preferably greater than 90%, preferably 100% LLDPE. In certain embodiments layer B is the same composition and / or thickness as layer D, as described herein. For the above ABCDE layer structure, preferably layer C comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%o, preferably greater than 90%, preferably substantially 100% LLDPE. Preferably, the LLDPE of layer C, and where other materials to LLDPE are present, layerC itself has a density in the range of 0.916-0.938 g / cm3, preferably 0.918-0.922 g / cm3,preferably about 0.920 g / cm3. Preferably, the LLDPE of layer C, and where other materials to LLDPE are present, layer C itself has a major melting peak in the range of 90°C-130°C, preferably 95°C-125°C, more preferably about 117°C. For the above ABCDE layer structure, preferably layer D may be any polyole^n, preferably a polyethylene, and preferably comprises greater than 50% by weight of LLDPE (Linear Low Density Polyethylene), preferably greater than 75%, preferably greater than 90%, preferably 100% LLDPE. In certain embodiments layer D is the same composition and / or thickness as layer B, as described herein. For the above ABCDE layer structure, preferably layer E comprises greater than 20% by weight of VLDPE or ULDPE (very Low Density Polyethylene or ultra Low Density Polyethylene), preferably greater than 50%, preferably greater than 75%, preferably substantially 100% VLDPE or ULDPE. Most preferably, layer E comprises substantially 2025.04.04 SPEC AS FILED 1242-10007WOULDPE. Preferably, the ULDPE of layer E, and where other materials to ULDPE are present, layer E itself has a density in the range of 0.870g / cm3to 0.890g / cm3, preferably 0.875-0.885 g / cm3, preferably about 0.880 g / cm3. Preferably, the VLDPE of layer E, and where other materials to VLDPE are present, layer E itself has a density in the range of 0.890g / cm3to 0.905g / cm3, preferably 0.900-0.902 g / cm3, preferably about 0.902 g / cm3. Preferably, the VLDPE of layer E, and where other materials to VLDPE are present, layer E itself has a major melting peak in the range of 70°C-130°C, preferably 80°C-125°C, more preferably about 100°C. Preferably, the ULDPE of layer E, and where other materials to ULDPE are present, layer E itself has a melting point in the range of 50°C- 110°C, preferably 60°C-100°C, more preferably about 70°C. The cling properties can be increased by increasing the percentage of ULDPE in the cling layer. For the above ABCDE layer structure, B, C and D can comprise nanolayers. The technology of producing nanolayers is described in more detail in US2009 / 0104424. For the above ABC layer structure, preferably layer A comprises more than one layer.Preferably layer A is comprised of 1 or 2 or 3 or up to n layers, wherein n belongs tonatural numbers. Thus, layer A is comprised of the layers A1, A2, A3, up to An, wherein n belongs to natural numbers. The layers A1up to Anare preferably produced by separate extruders, by the same extruder or by any combination thereof. Preferably layer is the outer layer of layer A, wherein the materials used in layer Ai are these compounded in layer A of an ABC layer stack. Preferably the density of layer Ai is that of said layer A of an ABC layer stack. Preferably the major melting peak of the materials compounded in layer Ai is that of said layer A of an ABC layer stack. For the above ABC layer structure, preferably layer B comprises more than one layer. Preferably layer B is comprised of 1 or 2 or 3 or up to k layers, wherein k belongs to natural numbers. Thus, layer B is comprised of the layers B1, B2, B3, up to Bk, wherein k belongs to natural numbers. The layers B1 up to Bk are preferably produced by separate extruders, by the same extruder or by any combination thereof. For the above ABC layer structure, preferably layer C comprises more than one layer. Preferably layer C is comprised of 1 or 2 or 3 or up to n layers, wherein n belongs to natural numbers. Thus, layer C is comprised of the layers C1, C2, C3, up to Cn, wherein n belongs to natural numbers. The layers d up to Cn are preferably produced by separate extruders, by the same extruder or by any combination thereof. Preferably layer C1is the outer layer of layer C, wherein the materials used in layer C1are these 2025.04.04 SPEC AS FILED 1242-10007WOcompounded in layer C of an ABC layer stack. Preferably the density of layer d is that of said layer C of an ABC layer stack. Preferably the major melting peak of the materials compounded in layer d is that of said layer C of an ABC layer stack. For the above (A1, A2, A3, up to An)(B1 , B2, B3, up to Bk)(Cn, Cn-1 , Cn-2, down to C-1 multi layer stack, preferably the materials used in any layer A2 up to An are these compounded in any layer of an ABC layer stack. Preferably the density of any layer A2 up to An is that of any layer of an ABC layer stack. Preferably the major melting peak of the materials compounded in any layer A2up to Anis that of any layer of an ABC layer stack. For the above (A1, A2, A3, up to Αη)(Β1, B2, B3, up to Bk)(Cn, Cn-1, Cn-2, down to C-1multilayer stack, preferably the materials used in any layer Bi up to Bk are thesecompounded in any layer of an ABC layer stack. Preferably the density of any layer Bi up to Bkis that of any layer of an ABC layer stack. Preferably the major melting peak of the materials compounded in any layer Bi up to Bkis that of any layer of an ABC layer stack. For the above (A1, A2, A3, up to An)(B1, B2, B3, up to Bk)(Cn, Cn-1, Cn-2, down to C-1) multi layer stack, preferably the materials used in any layer Cn down to C2 are these compounded in any layer of an ABC layer stack. Preferably the density of any layer Cndown to C2is that of any layer of an ABC layer stack. Preferably the major melting peak of the materials compounded in any layer Cn down to C2 is that of any layer of an ABC layer stack. In certain embodiments the lateral edges of the ^lm, along the machine direction, of said base ^lm are hemmed. The base ^lm material (and any reinforcing elements if present) may comprise polymers or copolymers, preferably synthetic polymers. Preferably the polymers are polyole^ns or non-polyole^ns such as polyamides or polyesters. Mixtures of different polyole^ns or mixtures of polyole^ns with non-polyole^ns can also be used. In the latter case compatibilization is preferred. Preferably the polyole^ns are independently selected from the group consisting of polyethylene, polypropylene, polyisobutylene, polybutyl- 1-ene, poly-4-methylpent-1-ene, polyisoprene, polybutadiene and copolymers and mixtures thereof, preferably ethylene based polymers. More preferably, the polyole^ns are polyethylene, more speci^cally Linear Low Density Polyethylene (LLDPE), Very Low Density Polyethylene (VLDPE), Ultra Low Density Polyethylene (ULDPE) or Low Density 2025.04.04 SPEC AS FILED 1242-10007WOPolyethylene (LDPE), produced as known in the art. The base ^lm and any reinforcing elements may be of the same material or different materials. The different layers of multilayer base ^lms may be of the same material or different materials. These are further described in our previous patent publication WO2011 / 026954. The reinforcing elements and the base ^lm materials may comprise polymers or copolymers, preferably synthetic polymers. Preferably the polymers are polyole^ns or non-polyole^ns such as polyamides or polyesters. Mixtures of different polyole^ns or mixtures of polyole^ns with non-polyole^ns can also be used.In general, a range of mechanical and thermomechanical techniques is available toperforate ^lms, including inter alia punching, pinning, die-cutting, laser irradiation,thermal irradiation, arc / spark, or any combination thereof. According to the invention,the perforation is performed by thermal irradiation during production of the ^lm, withouttouching the base material, which minimises any wasted ^lm material and reduces scrap production. The perforations may have a speci^c con^guration. For instance, when viewed in the transverse direction the perforations may be staggered or parallel. The perforations in the ^lm may be any shape. Preferably, the perforations are approximately circular or ellipsoid in shape. Typically, the diameter is at least 6 mm. Where the shape of perforation is approximately an ellipsoid. The ratio of the long axis to the short axis of the elliptical shaped perforation may vary from less than 10:1, preferably less than 6:1, more preferably less than 3:1 and most preferably approximately 1:1. In one embodiment of the invention, for circular shapes the radius is in the range 3.0 mm to 50 mm, preferably 10 mm to 30 mm, and most preferably 15 mm to 25 mm. In another embodiment, the length of the holes is typically in the range 5 mm to 80 mm, preferably 10 mm to 60 mm, and most preferably 15 mm to 30 mm. In another embodiment, the width of the holes is in the range 2.5 mm to 40 mm, preferably 5 mm to 30 mm, and most preferably 7.5 mm to 20 mm. The ^lm of the invention can be produced by any method appropriate for the production of plastic ^lms, for example by blown or cast extrusion. 2025.04.04 SPEC AS FILED 1242-10007WOAs used herein, blown extrusion may be carried out as follows. This process is the same as a regular extrusion process up until the die. The die is preferably an upright cylinder with a circular opening similar to a pipe die. The molten plastic is preferably pulled upwards from the die by a pair of nip rolls high above the die. Changing the speed of these nip rollers will change the gauge (wall thickness) of the ^lm. Around the die sits an air-ring. The air-ring cools the ^lm as it travels upwards. In the centre of the die is an air outlet from which compressed air can be forced into the centre of the extruded circular pro^le, creating a bubble. This expands the extruded circular cross section by some ratio (a multiple of the die diameter). This ratio, called the "blow-up ratio" can be just a few percent to more than 200 percent of the original diameter. The nip rolls flattenthe bubble into a double layer of ^lm whose width (called the "layflat") is equal 1 / 2thecircumference of the bubble. This ^lm can then be spooled or printed on, cut into shapes, and heat sealed. In the cast ^lm extrusion process, the molten polymer travels through a flat die system to adopt its ^nal flat ^lm shape. The die system is formed by the die and feedblock (if the process requires coextrusion) or simply the die, if the process is that of mono-layer extrusion. The process starts with the feeding of plastic resins by means of a gravimetric feeding system to one or more extruders. The materials are then melted and mixed by the extruders, ^ltered and fed to the die system. Immediately after exiting the die, the molten polymer enters the cooling unit where its temperature is lowered with a water cooled chill roll to freeze the ^lm. The ^lm is then passed downstream where the edges are trimmed. Further details of perforation methods, ^lm composition, and methods for forming the base ^lm can be found in our previous patent publication WO 2011 / 026954. In an embodiment a multiplicity of reinforcing elements may be placed and ^xed on the base ^lm after its perforation. The reinforcing elements comprising stretchable polymeric material are longitudinally oriented and at least one element is situated in a column of base ^lm not comprising holes. In an embodiment the reinforcing elements are applied to the base ^lm before its perforation.In an embodiment the reinforcing elements are ribbons or strips of stretchablepolymeric material. Each reinforcing element is made from one or more ribbons placedone above the other or a ribbon of a stretchable polymeric material that is folded atleast once. 2025.04.04 SPEC AS FILED 1242-10007WOIn another embodiment, the reinforcing elements are applied to the ^lm, the reinforcingelements are preferably bonded onto the base ^lm through heat fusion. During deposition, the reinforcing elements are generally at a temperature higher than roomtemperature and close to their crystallisation range, that is, preferably 1-100°C abovetheir crystallisation point, more preferably 1-80°C, more preferably 10-60°C, more preferably 20-50°C. The crystallisation point may be determined by means of Differential Scanning Calorimetry with a heating rate of 10°C / min. The holding force exerted on palletised goods is important. Holding force will de^ne the suitability, or lack thereof, of a packaging ^lm. The need for appropriate holding force will dictate the choice of polymer formulation, the cost of raw materials used andwill determine the number of wraps needed for the load to be secure on the pallet. Theholding force of the ^lm of the invention will typically be from about 5 kgf to about 60kgf (kilogram-force: about 49 to about 589 N), preferably from about 10 kgf to about 40kgf, most preferably 15 kgf to 30 kgf. Holding force is not the only parameter dictating the ef^cacy of pallet wrapping. Low necking effect permits reduction of the number of wraps needed during pallet product unitisation, thus a lower amount of ^lm needed per pallet, and better airflow in and out the wrapped pallet. Low necking also allows more effective coverage of the woodenpart of the pallet, thus helping to avoid transportation and safety problems. It is anobjective of the invention to provide a ^lm which applies more homogeneous distribution of forces around the pallet, which thus increases the stability of the pallet while at the same time reducing the need for wrapping material. It is a bene^t of the invention that the reinforced rim around each hole forms an strengthening point, providing improved tensile and tear properties in all directions and which is useful for wrapping on a pallet where forces can act in all directions. The invention will now be illustrated by the following Examples, in which the following points apply. Examples The following de^nitions apply to values and concepts discussed in these examples. Weight of ^lm: this is calculated by weighing a one metre length of the fully extended ^lm and it is expressed in grams (g) or in grams per square metre (g / m2). 2025.04.04 SPEC AS FILED 1242-10007WOWeight of specimen: the weight of the ^lm for a length equal to the grip-to-gripdistance, and it is expressed in grams (g). Displacement: the length change when a pulling / tensile force is applied to the material, expressed in millimetres (mm). Stretchability: the ability of the polymer to be deformed upon the application of a pulling force until it breaks. It is measured as a percentage relative to the initial length, i.e.: ^^^^^^^^^^ (%) = ^ℎ^^^^ ^^ ^^^^^ℎ^^^^^^^ ^^^^^ℎ × 100Stiffness: the ability of a material to resist deformation when a pulling / tensile force isapplied to the material. It is de^ned by the machine direction (MD) mechanical properties, such as Force and Elongation at NDR, and Force and Elongation at Break and the transverse direction (TD) mechanical properties, such as Force and Elongation at Break and the area under the force-displacement graph, as further de^ned below. A packaging ^lm should have an adequate holding force and stiffness which is suitablefor the intended application.Yield point: is the boundary between the elastic region and the plastic region duringelongation. To determine the yield point, force-elongation curves are obtained for ^lmsaccording to the invention and for ^lms of the prior art, using an Instron (Model 3365) tensile testing machine, a load cell of 1kN at room temperature and a constant testingrate of 3000mm / min. The widths of the specimens are 160 mm and the gaps betweenthe clamps are 100 mm. The ambient temperature when carrying out the experimentsis 23°C and the humidity is 50%.From the force-elongation curve, the yield point is the point that indicates the end of the elastic region and the beginning of the plastic region, or the strain hardening region for prestretched ^lms.Elongation at break: the percentage increase in length that a rim or a single hole willachieve before breaking or tearing and indicates the ability of a rim or a single hole toundergo signi^cant deformation before failure or tearing - it is a dimensionless number.Elongation at break / mass: the percentage increase in length that a rim or a singlehole will achieve before breaking or tearing divided by the mass of the specimen. It2025.04.04 SPEC AS FILED 1242-10007WOindicates the ability of a rim or a single hole to undergo signi^cant deformation beforefailure or tearing and it is expressed in % per gram (% / g).Maximum Force: the maximum amount of force that a rim or a single hole canwithstand during tension or tearing, and it is expressed in Newton (N).Maximum Force / mass: the maximum amount of force that a rim or a single hole canwithstand during tension or tearing divided by the mass of the specimen. It is expressedin Newton per gram (N / g).Tensile Energy: The area under the curve of the force versus extension / elongationuntil total fracture of the rim. It represents the absorbed energy and it is expressed inJoules (J).Tear resistance Energy: The area under the curve of the force versusextension / elongation until total tearing of the single hole, representing the work ofrupture and it is expressed in Joules (J). Time to rupture: The total time from the start of the tearing test until total tearing of the specimen has occurred and it is expressed in seconds (s).Thickness of the rim, tr: is the maximum thickness of the rim, once it is formed afterquenching, measured orthogonally from its lower edge to its higher edge, saidmeasurement running perpendicular to the plane of the base ^lm and including thethickness of the base ^lm directly below it. Width of the rim, wr: is the maximum width of the rim, once formed after quenching,measured from its inner edge to its outer edge, said measurement running parallel tothe plane of the base ^lm. In case the outer edge of the rim is not optically distinct, dueto the gradual decreasing of tr of the rim, then the wr of the rim is the maximum widthmeasured from the inner edge to the point where the tr is two times thicker than t0,tr=2*t0. Moreover, wr , shows how close to the hole the rim is formed.Inner edge of the rim: is the edge of the rim adjacent to each respective hole.Outer edge of the rim: is the edge of the rim opposite the inner edge.w1 portion: is a width between the inner edge of the rim and the thickest point of therim, tr.w2 portion: is a width between the thickest point of the rim, tr, and its outer edge.2025.04.04 SPEC AS FILED 1242-10007WOtr / t0: this ratio is the thickness of the rim versus the average base ^lm thickness, andshows the height of the rim in comparison to the height of the base ^lm.tr / wr,: this is the ratio of the maximum thickness of the rim over the maximum width ofthe rim, and it shows the distribution of the mass of the rim relative to its inner edge,i.e. it shows the proximity to the hole of the rim’s bulk mass.w1 / w2: this ratio is the symmetry of the shape of the rim, e.g. if w1 / w2 is close to 1, thenboth sides of the rim are substantially equal and symmetrical about tr.trMD / trTD: this ratio is the average tr measured in the MD divided by the average trmeasured in the TD, and shows the uniformity of the thickness of the rim along the MDand TDs. Examples: Production of a ^lm according to the inventionThe ^lm of the present invention comprises a cast or blown base ^lm material which isperforated. Macro perforations are performed using a thermal device which provides from a distance the necessary thermal energy to the solid base ^lm at speci^ed areas, forming a rim around each perforation / hole. During macro perforation, the base ^lm at targeted areas melts and its mass recedes from the thermal device, forming a continuous perimetric rim around each perforation / hole. The use of a thermal device held at a distance from the ^lm (i.e. in anembodiment where the thermal device does not contact the ^lm) minimises the degreeof mass lost from the ^lm material, thus the mass of the rim may be approximately equal to the mass moved from the heated area during perforation. The formation of a continuous perimetric boundary of accumulated material (i.e. areinforcing rim) around the edge of each hole may be varied using a number ofparameters, e.g. the shape, the size and the type of the thermal device, the working temperature, the working distance and the working time of the thermal device / source. It may also depend on the size and the shape of the formed perforation, the thickness of the base ^lm, the distance between the holes, the production process and the chemical structure of the base ^lm, and the pulling force during the perforation process. To achieve a continuous perimetric rim, the working distance of the thermal device must be such as to avoid any contact of the heating device with the solid base ^lm.Targeted temperatures must be much higher than the designated melting point of the2025.04.04 SPEC AS FILED 1242-10007WOsolid base ^lm material, for example the melting point for polyethylene is typically in therange 110 to 130°C. In this Example, perforation is performed using the non-contactthermal radiation method, as described in EP0820856. After the perforation process, the heated ^lm is quenched, and the quenching mayoccur by conduction. The heated areas around each hole are cooled down quickly, inless than 5 seconds, such that the temperature of each rim is below 30°C.The speci^cation simply sets forth a typical embodiment that will allow those skilled in the art to adapt the invention, however, it is apparent that the invention may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the appended claims. Examples 1,2 and 3 Example 1 Film: After the above-mentioned perforation and quenching processes, a^lm according to the invention was produced with a base ^lm thickness of 15 μm anda hole of 12 mm diameter, forming Example 1.Example 2 Film: After the above-mentioned perforation and quenching processes, a^lm according to the invention was produced with a base ^lm thickness of 9.5 μm, anda hole of 9 mm diameter, forming Example 2.Example 3 Film: After the above-mentioned perforation and quenching processes, a^lm according to the invention was produced with a base ^lm thickness of 20 μm, anda hole of 15 mm diameter, forming Example 3.Conventional Examples 1, 2 and 3Conventional Example 1 Film: A comparative example using a base ^lm of 15 μmthickness was prepared. During the whole perforation process, and due to thermalradiation, the base ^lm melts continuously, thus a hole of 12 mm diameter and a rimaround its edge are formed. After perforation the heated perforated areas were allowedto cool to room temperature simply by being left alone, and the outer edge of the rim is not substantially perpendicular to the plane of the base ^lm.Conventional Example 2 Film: A comparative example using a base ^lm of 9.5 μmthickness was prepared. During the whole perforation process, and due to thermalradiation, the base ^lm melts continuously, and a hole of 9 mm diameter and a rimaround its edge are formed. After perforation the heated perforated areas were allowed2025.04.04 SPEC AS FILED 1242-10007WOto cool to room temperature simply by being left alone, and the outer edge of the rim is not substantially perpendicular to the plane of the base ^lm.Conventional Example 3 Film: A comparative example using a base ^lm of 20 μmthickness was prepared. During the whole perforation process, and due to thermalradiation, the base ^lm melts continuously, and a hole of 15 mm diameter and a rimaround its edge are formed. After perforation the heated perforated areas were allowedto cool to room temperature simply by being left alone, and the outer edge of the rim is not substantially perpendicular to the plane of the base ^lm. Measuring the characteristics of the rim around the holeThe characteristics of the rims formed according to the invention and of the prior artwere measured using Scanning Electron Microscopy (SEM). For each of theaforementioned ^lms, ^ve holes were selected to measure the average characteristicsof their rims along the MD and TD.The selected holes must be well perforated / opened and be representative of themajority of the holes of the ^lm. In case of reinforced perforated ^lm, the holes shouldnot be in contact with the reinforcing element(s). However, if the holes are in contactwith the reinforcing element(s), then the reinforcing element(s) must be removed beforethe measurement, otherwise its dimensions should be subtracted from themeasurements. In these Examples, the ^lms were not reinforced.Each hole was cut into four pieces. The ^rst cutting line is parallel to MD and the secondcutting line is parallel to TD. Both cutting lines must pass through the center of the hole.From each cross section, the thickness, tr, the width wr and the distances w1 and w2, were measured for each rim. In Table 1, the average value of each characteristic along MD and TD are presented, as well as the overall average value of each characteristic. 2025.04.04 SPEC AS FILED 1242-10007WO,mlss ) ^ e m e n 55.0 55.0 s kμ(1 9 2 1 9 2 aci t 0Bhtreteelo ) m H m 2 a 1 9 51 21 9 51 ifm(D o lle ) arg m 1 3 5 6 3 earv eμ(1 7 1 2 5 8 6 3 1 2 2 2 O v 2 1 1 1 A w lle ) arg m ear2 6 5 0 v eμ(0 8 v 1 1 2 41 9 5 2 51 82 O A w 2 w 0 3 5 D 6 4 50 03 5 0 e ) T 9 2 1 1 2 3 g 1 1 arm eμ(D 6 0 0 2 2 0 v 0 7 8 6 A M 1 3 02 21 21 11 1 w D 4 2 2 0 5 5 e T 8 2 11 03 41 44 g ) arm eμ(D 0 3 1 0 6 0 v M 21 3 8 9 5 6 A 1 2 1 4 lle,) arg ears’htm 0 7 5 v emidiμ(3 6 0 8 1 8 r 12 5 03 51 41 6 O v R w 1 A w , eht0 7 0 8 0 D 6 0 9 5 gd) T 8 4 1 6 3 7 airm 1 2 1 1 1 ew μ(vs’r Amiw D 6 5 3 0 5 0 R M 42 6 8 6 3 5 3 1 4 2 1 61 l,le s args’se ) arn m 0 0 1 5 0 0 emiμ7 5 0 0 2 v e k( r1 2 1 4 1 O v R AcihttO W s 7ci0ts t r00ire,D 2 s T 7 5 3 0 4 9 0 7 4 3 11-e1 1 1 1 2tg 4 as’se ) 2carre a vmin m1D R kμ(7 0 Eh AciD 4 0 4 5LM 6 5 1 1 4 2IFC ht1 2 1 1 SiAml lCR:alE P1 1 2 3n1an2an3 Seoeo o 4Elelelit litelitel0.L p p p n p n p p 4B m m m e e ne0.5A a a a v m T x n a v m n a v m 2 n a 0 E x E x E o x E o x E o x E 2 C C Ces / ’s,s gsss armieeg’e D eRnkacrminTeRkt / r7 D D 0 9 0 8 0 vDivciM A MhtA Tht t r9.02.10.11.11.11.1 e / gs e ars g eaenrvk e c v AlilhAt lalres’ar2 vme,2 3 5 1 8 3 0 Oiv R O ww / t r5.18.13.10.00.01.0 e / gs e ars g e enarvk ev AclilhAart lles’ar1 vmOiev,1 R O ww / 7 0 8 6 7 2 tr6.18.13.13.02.04.0 eg arel,2 vlAa wlrlee arvg , Oar2 ev / 1 ewv / 1 2 9 3 0 5 9 3 2 3 O w A w.0.1.02.01.02.0 ’s,mihR ltladiegrewarvs’eO v / miAsRlls e a en g r ekavcrie r 0 9 7 7 3 7 Ohtv Aw / t r8.08.06.00.00.00.0 )d’seumimnitRle^n ge oc(ars O a W7seB v / , 00ictsAss s 0 1irlla ese -2 r nk n 4 k 2etc eavcicirOhthtt / 01D tr11 5 0 E 1 7 4 6 aLIhFSCmlACial lER n an an P:1 2 3o1 e it1oit2oit3 S4 0Elelelnelnelnel .4L p p p ep ep ep0m m v v v.5B A a a ma n m T x oa nma nma 202 E x E x E Cx o E Cxo E Cx ETest 1: Tensile behavior of each rim The tensile behavior of rims formed according to the invention, Examples 1, 2, 3 and ofrims according to prior art, Conventional Example 1, 2, 3, were measured along theMD, using an Instron (Model 3365) tensile testing machine, having a load cell of 50N at 5room temperature and the constant testing rate was 1000mm / min. Each grip consistsof a stainless steel hook (2.5 mm x 16 mm). The surface of each hook must be smooth,to prevent breaks and tears at the portions of the rim that are in contact with the hooks. Using a sharp cutting tool (e.g. a blade or a cutter) the non-perforated area (base ^lm material) around the rim was removed. The average mass of the rims was measured10 before the tensile test, and it is expressed in grams (g). The temperature when carryingout the experiments was 23°C – 25 °C and the humidity was 50%.For each ^lm, ^ve rims were tested and the average characteristics and tensile behaviorare shown in Table 2. Table 2: Tensile testing data of a rimProperty ExampleConventional Example Conventional Example Conventional 1 Example 1 2 Example 2 3 Example 3Base ^lm thickness (μm) 15 15 9.5 9.5 20 20Diameter of hole (mm) 12 12 9 9 15 15Average Mass of specimens (g) 0.0014 0.0030 0.0003 0.0011 0.0016 0.0058Average Tensile Energy (J) 0.04 0.07 0.009 0.013 0.06 0.20Average Elongation at break (%) 596 456 410 343 552 848Average maximum Force (N) 0.91 1.51 0.21 0.72 0.92 2.67Average Tensile Energy / 30.0 24.2 30.0 11.8 37.5 34.5Average Mass (J / g) Average Elongation at break / 418.137 149.928 1.366.667 311.818 345.000 146.207Average Mass (% / g) Average maximum Force / 636 497 700 655 575 460Average Mass (N / g) 15 2025.04.04 SPEC AS FILED 1242-10007WOTest 2: Tear resistance of a single hole The tear resistance of a single hole formed according to the invention (Examples 1, 2,3) and of prior art (Conventional examples 1, 2, 3) were measured using an Instron(Model 3365) tensile testing machine. A load cell of 50N and a constant testing rate of 5 1000mm / min were chosen. The length of the specimen was the grip-to-grip distance, which was ~ 30 mm and the width of the specimen was ~ 25mm. Two cracks of ~1 mm were created along the TD sides of the specimen, approximately at the middle of the length of the specimen, at ~ 30mm. Due to the con^guration of the experiment the two cracks are directed at the same time towards the reinforced hole. The average mass of10 the specimens which was considered for the calculations was measured after the testsand it is expressed in grams (g). The ambient temperature when carrying out the experiments was 23°C and the humidity was 50%. For each ^lm, ^ve specimens were tested, and the averagecharacteristics and the tear behavior are shown in Table 3.15 Table 3: Single hole tear resistance dataProperty ExampleConventional Example Conventional Example Conventional 1 Example 1 2 Example 2 3 Example 3Base ^lm thickness (μm) 15 15 9.5 9.5 20 20Diameter of hole (mm) 12 12 9 9 15 15Average Mass (g) 0.0068 0.0068 0.0055 0.0055 0.0120 0.0120Average Tear Resistance Energy0.05 0.03 0.03 0.02 0.07 0.04(J)Average Elongation at break (%) 134 120 112 86 145 125Average maximum Force (N) 2.6 1.9 1.9 1.5 3.7 2.3Average Time to rupture (sec) 1.66 1.60 1.60 1.47 1.96 1.81Average Tear Resistance Energy / 7.4 4.4 5.5 3.6 5.8 3.3Average Mass (J / g) Average Elongation at break / 19.706 17.647 20.364 15.636 12.083 10.417Average Mass (% / g) Average maximum Force / 382 279 345 273 308 192Average Mass (N / g) Time to rupture / Average Mass244 235 291 267 163 151(sec / g) Table 1 shows that for the same base ^lm thickness, the rims formed according to theinvention are taller and narrower than the rims of prior art. This occurs due to the2025.04.04 SPEC AS FILED 1242-10007WOquenching step, because the heated areas around each hole are cooled down quickly,thus the heated areas are solidi^ed quickly and abruptly, forming thus a taller andnarrower rim closer to the hole.Moreover, Table 2 and Table 3 show that the tensile behavior (Average Tensile Energy / Average Mass, Average Elongation at break / Average Mass, and Average maximumForce / Average Mass) and the tear behavior (Average Tear Resistance Energy / AverageMass, Average Elongation at break / Average Mass, Average maximum Force / AverageMass) and Time to rupture / Average Mass) of taller and narrower rims (Examples 1, 2,3) are improved compared to the shorter and broader rims of prior art (ConventionalExamples 1, 2, 3). As a consequence, the presence of rims formed according to theinvention closer to the hole signi^cantly improves the behavior of the perforated ^lm.2025.04.04 SPEC AS FILED 1242-10007WO

Claims

CLAIMS 1. A stretch ^lm comprising, abase ^lm (1) comprising a stretchable polymer ^lm material arranged in aplurality of columns; a multiplicity of holes (2) in the base ^lm arranged in a plurality of columns; wherein the plurality of columns of base ^lm and the plurality of columns of holes extend along a longitudinal direction of the base ^lm; wherein each column of holes is separated from each adjacent column of holes in a transverse direction of the base ^lm by one or more columns of base ^lm; wherein the base ^lm has a plane oriented along the longitudinal and transversedirections of the ^lm, and wherein the base ^lm has a thickness t0;wherein each hole of the multiplicity of holes is reinforced with a respectivereinforcing rim (3), wherein each rim comprises a localised accumulation of stretchablepolymer ^lm material which forms a continuous perimetric circuit around each respective hole, wherein each rim has a cross-section de^ned by an inner edge (4) of the rim adjacent to each respective hole and an outer edge (5) of the rim opposite the inner edge, wherein the cross-section of the rim has a width wrmeasured between the inner edge and the outer edge of the rim, and wherein the cross-section has a thickness tr measured at the thickest point of the rim; wherein ^^ ^^^ > 2; and wherein^^^ ^^ is from 0.2 to 6.

2. A ^lm according to claim 1, wherein ^^^ ^^ is from 0.2 to 5, or from 0.2 to 4, or from0.2 to 3, or from 0.2 to 2.5, or from 0.3 to 2, or from 0.5 to 2, or from 0.5 to 1.5, or from0.5 to 1.3, or most preferably from 0.5 to 1.

1.

3. A ^lm according to claim 1 or claim 2, wherein the width wr is from, 0.02 to 1.0 mm,optionally from 0.02 to 0.8 mm, optionally from 0.02 to 0.6 mm, optionally from 0.03 to0.6 mm, optionally from 0.03 to 0.5 mm, optionally from 0.03 to 0.45 mm, optionallyfrom 0.03 to 0.4mm.

4. A ^lm according to any preceding claim, wherein the base ^lm has average thicknesst0, and wherein tr is thicker than t0 by 2 to 25 times, or from 2 to 20 times, or from 2 to2025.04.04 SPEC AS FILED 1242-10007WO18 times, or from 2 to 15 times, or from 2 to 14 times, or from 2 to 13 times, or from3.5 to 13 times, or most preferably from 4 to 13 times.

5. A ^lm according to any preceding claim wherein the width wr comprises two portions w1 and w2, wherein w1 is a width between the inner edge of the rim and the thickest point of the rim, wherein w2 is a width between the thickest point of the rim and theouter edge of the rim, wherein ^^ + ^^ = ^^ , and wherein^^^ ^^ is from 0.25 to 3.5,preferably from 0.35 to 3, preferably from 0.35 to 2.5, preferably from 0.35 to 2,preferably from 0.45 to 2, preferably from 0.45 to 1.6, preferably from 0.45 to 1.4,preferably from 0.45 to 1.3, most preferably from 0.45 to 1.2.

6. A ^lm according to claim 5, wherein ^^^ ^^ is from 0.45 to 3.5, and / or wherein^^^^^is from 0.45 to 3.5, preferably wherein^^^ ^^^^ is from 0.45 to 3, and / or wherein ^ ^^ isfrom 0.45 to 3, preferably ^^^ ^^ is from 0.45 to 2.5 and / or wherein^^^ ^^ is from 0.45 to2.5, preferably ^^^ ^^ is from 0.5 to 2.5, and / or wherein^^^ ^^ is from 0.5 to 2.5,preferably ^^^ ^^ is from 0.7 to 2.5, and / or wherein^^^ ^^ is from 0.7 to 2.5, preferably^^^ ^^ is from 0.85 to 2, and / or wherein^^^ ^^ is from 0.85 to 2, preferably^^^ ^^ is from0.9 to 2, and / or wherein^^^ ^^ is from 0.9 to 2.

7. A ^lm according to any preceding claim wherein the ratio of the average trmeasured in the MD to the average tr measured in the TD, trMD / trTD, is from 0.3 to 2.5,or from 0.5 to 2.5, or from 0.8 to 2.5, or from 0.9 to 2.5, and is most preferably from 0.9to 1.

6.

8. A ^lm according to any preceding claim, wherein each rim is present on only one face of the base ^lm.

9. A ^lm according to any of claims 1 to 7, wherein each rim extends perpendicularly to the plane of the base ^lm through each respective hole and comprises a further localised accumulation of stretchable polymer ^lm material on the opposite face of the base ^lm, such that the rim is present on both faces of the base ^lm around each respective hole.

10. A ^lm according to claim 9, wherein each rim has substantially similar cross-section on both faces of the base ^lm. 2025.04.04 SPEC AS FILED 1242-10007WO11. A ^lm according to claim 9 or 10, wherein each rim is substantially symmetrical above and below the plane of the base ^lm.

12. A ^lm according to any preceding claim, wherein each rim has substantially non-uniform width around the continuous perimetric circuit and / or wherein each rim hassubstantially non-uniform thickness around the continuous perimetric circuit.

13. A ^lm according to any of claims 1–11, wherein each rim has substantially uniformwidth around the continuous perimetric circuit and / or wherein each rim hassubstantially uniform thickness around the continuous perimetric circuit.

14. A ^lm according to any preceding claim, wherein each rim is preserved during stretching of the ^lm up to at least the yield point of the ^lm.

15. A ^lm according to any preceding claim, further comprising one or more reinforcing elements disposed along the columns of base ^lm.

16. A method of producing a stretch ^lm according to any of claims 1 to 15, comprising providing an initial extruded stretch ^lm; perforating the initial stretch ^lm to form a base ^lm comprising a stretchable polymer ^lm material comprising columns of holes in the longitudinal direction, wherein each hole is separated from each adjacent hole in the transverse direction by at least one column of base ^lm, wherein perforating the initial stretch ^lm is performed by using a thermal device, wherein a rim is instantaneously formed by localised heatingfrom the device; andapplying to each formed rim a quenching means suf^cient to deliver localised quenching.

17. A method according to claim 16, wherein the quenching means deliver a cooling rate of at least 1°C · s-1, or at least 10°C · s-1, or at least 15°C · s-1, or at least 20 °C · s-1, or at least 25°C · s-1, or at least 50°C · s-1, or at least 70°C · s-1, or at least 100°C · s-1, or at least 120°C · s-1, or at least 150°C · s-1, or at least 200°C · s-1, or at least 300°C · s-1, or at least 350°C · s-1, or at least 400°C · s-1, or at least 450°C · s-1, or at least 500°C · s-1, or at least 550°C · s-1, or at least 600°C · s-1, or at least 650°C · s-1, or at least 700°C ·s-1, or at least 750°C · s-1, or up to 800°C · s-1.2025.04.04 SPEC AS FILED 1242-10007WO18. A method according to claim 16 or 17, wherein the quenching means achieve areduction in temperature in each rim of at least 70°C, or at least 90°C, or at least 100°C,or at least 200°C, or at least 250°C, or at least 300°C, or at least 350°C, or up to 400°C.

19. A method according to any of claims 16–18, wherein the temperature of each rim is reduced to below 50°C, or to below 40°C, or to below 35°C, or to below 30°C, or to below 25°C, or to below 20°C, or to below 10°C, or to below 4°C, or to below 0°C, or to below -10°C, or preferably to below -20°C, most preferably to below -30°C.

20. A method according to any of claims 16–19, wherein the quenching means are applied for a duration of from 0.5 to 30 seconds, 0.6 to 20 seconds, preferably from 0.8 to 10 seconds, most preferably from 1 to 5 seconds.

21. A method according to any of claims 16–19, wherein the quenching means are applied immediately after the formation of each rim.

22. A ^lm obtainable by the method of any one of claims 16–21.

23. Use of a stretch ^lm according to any of claims 1–15 or 22 for packaging.

24. The use according to claim 23, wherein the packaging is applied for unitising goods.

25. The use according to claim 23, wherein the packaging is applied to silage. 2025.04.04 SPEC AS FILED 1242-10007WO

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