Film material with protective film layer and methods

Abstract

Film material and a method for its application, particularly suitable for protective and adhesive films used in wrap film applications, is provided. The film material 1000 comprises a flexible base film 100 with a first surface 120 and an opposite second surface 140, an adhesive layer 200 bonded to the second surface 140 of the base film 100, a release liner 300 releasably attached to the adhesive layer 200, and a protective film layer 400 releasably attached to the first surface 120 of the base film 100. The protective film layer 400 features an adherent layer comprising a thermoplastic polymer, an elastomeric polymer or a thermoplastic elastomer. This film material can be wound into a roll or converted into discrete sheets, providing high lifting resistance, superior optical clarity, and enhanced durability.

Description

[0001] PA102760W002

[0002] FILM MATERIAL WITH PROTECTIVE FILM LAYER AND METHODS

[0003] TECHNICAL FIELD

[0004] The present invention relates to film materials, particularly those with protective film layers that are resistant to surface impressions. More specifically, it pertains to multilayer films that can be manufactured and stored in roll form while maintaining resistance to surface impressions and providing enhanced application performance.

[0005] BACKGROUND

[0006] Protective Film Layers (PFL) are essential in the wrap film industry, particularly for gloss and high gloss wrap film series, to shield the film surface from manufacturing-related surface impressions and scratches during application. The current PFLs, exhibit significant lot-to-lot variations, resulting in defects such as specks, blooming, air bubbles and fine lines. These imperfections cause damage to the wrap film surface, leading to increased waste during manufacturing and customer complaints due to compromised visual appearance.

[0007] Furthermore, existing PFLs suffer from low bonding force, causing them to delaminate from the wrap film surface when stretched during application, particularly in recesses of car bodies. The high friction of these PFLs also impedes the slideability of application tools, reducing both the speed and quality of application.

[0008] Traditional manufacturing processes for wrap films involve coating a carrier web with a top film layer, followed by additional layers, and then stripping the films from the carrier web before lamination to an adhesive -coated liner. This stripping can occur offline or inline to minimize surface impressions caused by winding tensions when the film is in roll form. However, once stripped, the film surfaces are exposed to potential damage, making them susceptible to surface impressions during winding and storage and to scratches during application.

[0009] Despite various processing and material changes made to minimize undesirable surface impressions, post-processing is often required to smooth out such imperfections, which can be timeconsuming and costly. Therefore, there is a need for a surface-impression-resistant film construction that minimizes or eliminates surface impressions on films, such as high gloss, glossy, satin, or matte films and a PFL with less defects that improves overall application performance.

[0010] SUMMARY

[0011] In accordance with an embodiment of the film material described herein, a film material is provided, comprising a flexible base film comprising a first surface and an opposite second surface, an adhesive layer with a first surface bonded to the second surface of the base film and an opposite second surface, a release liner releasably atached to the second surface of the adhesive layer, and a protective fdm layer with an adherent layer releasably attached to the first surface of the flexible base film. This film material can be wound around a central longitudinal axis to form a cylindrical roll or converted into discrete sheets of film material.

[0012] The protective film layer may be optically clear, transparent, translucent, or colored.-The protective film layer may be conformable, have a tensile strength in the range of about 5.0 to 40 N / mm2and an elongation range larger than 100%. It may be releasably attached to the first surface of the flexible base film with a bonding force in the range of about 2 to 20 cN / 25.4 mm measured at a separation speed of 2,286 mm / min.

[0013] The flexible base film can include multiple material layers, at least one of a single layer polyvinylchloride (PVC) film, a double layer polyvinylchloride film, a triple layer polyvinylchloride film, a composite film, a polyester-based film, an acrylic -based film, a polyester film, a polypropylene film, a polyurethane film, and a polyolefin film. The first surface of the flexible base film may have a glossy, satin, or mate surface.

[0014] In use, a portion of the length of film material can be unwound from the roll and converted into discrete sheets of film material, wherein the protective film layer is removable from the discrete sheets of film material. This enables easy application to various substrates.

[0015] In accordance with the exemplary embodiments provided herein, a method of applying a sheet of film material to a substrate includes positioning a sheet of film material adjacent to an outer surface of a substrate. The sheet of film material comprises a flexible base film with a first surface and an opposite second surface, an adhesive layer with a first surface bonded to the second surface of the base film and an opposite second surface, a release liner releasably atached to the second surface of the adhesive layer, and a protective film layer releasably atached to the first surface of the flexible base film. The method further includes removing the release liner from the second surface of the adhesive layer and applying the adhesive layer to the outer surface of the substrate. The step of removing the protective film layer from the first surface of the film material may occur either before or after applying the adhesive layer to the outer surface of the substrate, potentially using application tools such as a squeegee to ensure a smooth, defect-free application.

[0016] The novel construction and composition of the protective film layer provide a solution to the issues of surface impressions, defects, and application performance, ensuring enhanced durability, reliability, and visual appeal of the wrap films. The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0018] FIG. 1 is the cross-sectional view of the film material according to various exemplary embodiments.

[0019] FIGA. 2A-2D illustrate the effect of the protective film layer of the present invention in significantly reducing the occurrence of matte spots when heat is applied during the application process as compared to existing protective film layers.

[0020] FIGS. 3 A and 3B are schematic drawings of a test panel used in connection with a lifting test as set out in the examples.

[0021] FIGS. 4A, 4B, and 4C illustrate the lifting of the Current-PFL (FIG. 4C) compared to PFL-1 (FIG. 4A) and PFL-2 (FIG. 4B) on a test panel.

[0022] FIGS. 5A and 5B illustrates the lifting of Current-PFL (FIG. 5A) vis a vis PFL-3 (FIG. 5B).

[0023] FIGS. 6A and 6B illustrate lower DOI and RIQ values of 2080 high gloss film surface after removal of Polifilm PFL.

[0024] FIGS. 7A and 7B illustrate higher DOI and RIQ values of 2080 high gloss film surface after removal of Polifilm PFL.

[0025] DETAILED DESCRIPTION

[0026] In one aspect, the present application relates to conformable film material such as wrap films. The film materials related to the current invention can be used for a broad range of outer surfaces of substrates. Examples for substrates are vehicles and construction elements.

[0027] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0028] In the following disclosure, the following definitions are adopted.

[0029] As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0030] The words "preferred" and "preferably" refer to embodiments described herein that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

[0031] The term “vehicle” refers to vehicles for automotive, rail, aerospace or maritime applications.

[0032] The term “construction elements” include window glass, window frames, doors, panels, boards, tiles, cabinets, furniture’s, claddings or booth constructions.

[0033] "High gloss surface" refers to a highly reflective and smooth finish on a film surface, creating a mirror-like effect that enhances the visual appeal by making colors appear more vibrant and details more pronounced. The gloss level of high gloss surfaces is at least 80 measured at 60° angle and the distinctness of image at least 70.

[0034] "Glossy surface" refers to a shiny and smooth finish on a film surface that is partially reflective creating a partial mirror effect. The gloss level of glossy surface is at least 80 measured at 60° angle, the distinctness of image might be lower than 70.

[0035] "Satin surface" refers to a finish on a film surface that offers a subtle sheen and smooth appearance, providing a middle ground between glossy and matte finishes by reflecting some light while hiding minor imperfections better. The gloss level of satin surfaces measured at 60° angle may range from 10 to 80.

[0036] "Matte surface" refers to a non-reflective, flat finish on a film surface that diffuses light, resulting in a subdued and muted look that hides fingerprints, smudges, and surface imperfections while providing a sophisticated and understated appearance. The gloss level of matte surfaces is lower than 10 measured at 60° angle.

[0037] Gloss level can be determined according to ASTM D2457. Distinctness of image can be measured according to ASTM D5767-18.

[0038] Reference throughout this specification to "one embodiment," "certain embodiments," "one or more embodiments" or "an embodiment" means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as "in one or more embodiments," "in certain embodiments," "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0039] Referring now to the figures, and initially to FIG. 1, an exemplary embodiment of a film material 1000 is illustrated. The film material includes a flexible base film 100 with a first surface 120 and an opposite second surface 140, an adhesive layer 200 comprising a first surface 220 and an opposite second surface 240, a release liner 300 releasably attached to the second surface 240 of the adhesive layer 200, and a protective film layer 400 with an adherent layer releasably attached to the first surface 120 of the flexible base film 100. Film Material without Release Liner 500 comprises the flexible base film 100 with the Protective Film Layer 400 and the adhesive layer 200. Adhesive coated base film layer 600 comprises the Base Film 100, the adhesive layer 200 and the Release Liner 300.

[0040] The base film 100 is preferably a conformable film material and includes one or more layers. As used herein, the term "conformable" generally refers to a film that can materially or completely take on the shape of a three-dimensional substrate containing convex features, concave features, and / or other shapes or contours. However, the determination of the conformability of a film is not limited to situations in which it is actually applied to such a substrate, but also that the film has this capability prior to being applied to a substrate. In embodiments, taking on such a shape is possible without undesired changes to the structural integrity and / or the aesthetic appearance of the film. In this sense, conformable films are distinguishable from non-conformable films that may be capable of being applied to planar surfaces and / or curved slightly around surfaces that have a sufficiently large radius of curvature, such as a large cylinder, but which are not possible to apply to a more complicated three-dimensional substrate.

[0041] Factors that can influence the conformability of a film include the identity of the material used to make the film, the molecular weight of such material, the conditions to which such film is subjected (e.g., temperature, radiation exposure, and humidity), and the presence of additives in the film material (e.g., plasticizer content, reinforcing fibers, pigments, stabilizers, and hardness enhancing particles).

[0042] The flexible base film 100 of the film material 1000 can be constructed from various materials and comprises at least one of a single layer polyvinylchloride film, a double layer polyvinylchloride film, a triple layer polyvinylchloride film, a composite film, a polyester-based film, an acrylic -based film, a polyester film, a polypropylene film, a polyurethane film, and a polyolefin film. It is approximately 50 pm thick with an elongation level of at least 50%, but can even be thinner than 15 pm or thicker than 150 pm. Other exemplary materials that can be used as base film 100 include: a double layer polyvinylchloride film that is approximately 75-95 pm thick with an elongation level of at least 50%; a triple layer polyvinylchloride film that is approximately 130 pm thick with an elongation level of at least 50%; a composite film that includes one or two PVC layers and one or two polyester-based layers, with a thickness between approximately 50 and 150 pm; a polyester-based film consisting of an iso-cyanate modified polyester crosslinked with a melamine resin that is approximately 30 to 95 pm thick with an elongation of greater than 50%; and an acrylic-based film consisting of modified acrylic resins having an elongation level of at least 50%; other polyester-based films; polypropylene films; polyurethane films; polyolefin films; and combinations of these and other films that are thinner or thicker than described above and / or that have laiger or smaller elongations than described above. With these exemplary materials for the base film 100, the elongation was determined according to DIN EN ISO 527-3:2019-12. Additionally, the first surface 120 of the flexible base film 100 can have different finishes such as high gloss, glossy, satin, or matte, which allow the flexible base film to be tailored for specific aesthetic and functional requirements.

[0043] In an embodiment, the base film 100 is provided with a relatively smooth surface to which the protective film layer 400 can be applied. In exemplary embodiments, the base film 100 has a surface roughness of Ra less than approximately 1 pm or a surface roughness of Rz less than approximately 6 pm, wherein the surface roughness was determined according to DIN EN ISO 4287:2010-07.

[0044] The adhesive layer 200 and release liner 300 may include, for example, an acrylic adhesive and a siliconized liner, respectively. In an exemplary embodiment, the adhesive layer 200 may include a number of materials or combinations of materials, including pressure-sensitive adhesives, films having a network of microstructure air channels in the adhesive that allow air to escape laterally beneath the film (e.g., films available under the trade designation "COMPLY", commercially available from the 3M Company of St. Paul, Minnesota, USA), and / or material commercially available from the 3M Company of St. Paul, Minnesota, USA under the trade designation "CONTROLTAC" that minimizes the initial contact area of adhesive and allows an applicator to reposition the film during application. A release liner 300 can be positioned adjacent to the adhesive layer 200, which is generally a protective film or paper layer that covers the adhesive layer until it is desired to expose the adhesive, such as for application of the film material 1000 to a surface.

[0045] The protective film layer 400 may be a multilayer construction and may include at least one layer comprising thermoplastic polymers, which may include polyethylene such as linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), high density polyethylene (HDPE) or elastomeric polymers such as ethylene vinyl acetate copolymers or thermoplastic elastomers such as synthetic rubbers like styrene ethylene butadiene styrene block copolymer (SEBS). It may further include an adherent layer comprising a polymer adhesive such as elastomer based adhesives like polyisoprene, styrene block copolymers, styrene butadiene copolymers, polybutadiene or polyisobutylene or acrylic based adhesives like C4-C11 polymer based.

[0046] The protective film layer 400 is releasably attached to the first surface 120 of the flexible base film 100 and is designed to have a dynamic coefficient of friction of less than about 0.2 at a sled speed of lOOmm / min ensuring excellent slideability when used with a squeegee buffer.

[0047] Additionally, adherent layer of the protective film 400 features a bonding force to the flexible base film 100 in the range of about 2 to 20 cN / 25.4 mm, preferably in the range of 2 to 15 cN / 25.4mm and more preferably in the range of 2 to 6 cN / 25.4mm, measured at a separation speed of 2,286 mm / min. In a certain embodiment, the protective film layer 400 is also designed to have a tensile strength in the range of about 5.0 to 40 N / mm2, preferably in the range of 10 to 30 N / mm2and more preferably in the range of 20 to 25 N / mm2and a thickness of less than 30 pm.

[0048] It can be conformable with an elongation that is the same or higher than the base film and may be optically clear, transparent, translucent, or colored.

[0049] In a particular embodiment, the protective film layer 400 can have an elongation range of more than 100 %.

[0050] Furthermore, as shown in FIGS. 2A-2D, the protective film layer 400 significantly reduces the occurrence of matte spots when heat is applied during the application process, compared to existing protective film layers. These features allow the flexible base film 100 and the protective film layer 400 to work together, providing superior protection, ease of application, and enhanced visual and functional performance.

[0051] The protective film layer 400 can be applied on the base film 100 by a lamination process that includes pressing both films between two rolls. The pressure between both rolls depends on the type of rolls and processing speed, wherein the parameters are preferably adjustable to prevent air entrapment between the film layers. The protective film layer 400 is generally considered to be protecting the outer or "face" side of the base film 100 during the manufacturing process. This protective film layer 400 can remain on the final product even during the final application process carried out by users of the film material 1000.

[0052] The bond between the base film 100 and the protective film layer 400 is achieved by weak intermolecular forces. The bonding forces can be determined according to ASTM D3330 methods. In one example, the bonding force between the base film 100 and protective film layer 400 can be in the range of approximately 2 to 20 cN / 25.4 mm measured at a separation speed of 2,286 mm / min, although higher or lower bonding forces are contemplated.

[0053] The protective film layer 400 is provided to protect the "face" surface of the base film 100 and thus will also protect the stripped film from "blocking", thereby allowing the film material 1000 to be stored for a substantially longer time without adversely impacting the product. Depending on customers’ needs, the protective film layer 400 may or may not remain on the final product during application to a surface. If the protective film layer 400 remains on the final product during application to a surface, it can prevent the formation of scratches and even improve the application characteristics. If the protective film layer 400 is not desired for the final application, it can be stripped during a converting process. The protective film layer 400 will generally be easy to remove from the base film 100 without requiring additional cleaning or processing of the top surface of the base film 100.

[0054] In an embodiment, the protective film layer 400 may be at least one of optically clear, transparent, translucent, and colored. In certain embodiments, the protective film layer 400 is optically clear, with a total transmittance of greater than 88% in order to be able to inspect the final product during processing, such as can be determined according to ASTM D1746 methods. Clear protective films will also not impact the visual appearance of the final color. However, it is also possible to use tinted films, translucent films, and / or colored films.

[0055] In a further embodiment, a sheet of film material 1000 is provided, comprising a flexible base film 100 with a first surface 120 and an opposite second surface 140. An adhesive layer 200 is bonded to the second surface 140 of the base film. A release liner 300 is releasably attached to the second surface 240 of the adhesive layer. A protective film layer 400 with an adherent layer is releasably attached to the first surface 120 of the flexible base film, having a dynamic coefficient of friction less than about 0.2 at a sled speed of 100 mm / min, which ensures excellent slideability and ease of application.

[0056] Yet another embodiment involves a method of applying a sheet of film material 1000 to a substrate. The method includes positioning the sheet adjacent to the outer surface of the substrate, removing the release liner from the adhesive layer, and applying the adhesive layer to the outer surface of the substrate. The protective film layer 400, with an adherent layer, remains attached to the first surface of the flexible base film during this process. The method further includes the step of removing the protective film layer from the first surface of the film material. This may occur either before or after applying the adhesive layer to the outer surface of the substrate, potentially using application tools such as a squeegee to ensure a smooth, defect-free application.

[0057] EXAMPLES

[0058] Objects and advantages of this disclosure are further illustrated by the following non-limiting examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this disclosure.

[0059] Table 1 Materials Example 1- Tensile strength and elongation

[0060] Tensile strength is measured with a tensile testing machine. A prepared film sample, typically rectangular or dumbbell-shaped, is clamped at both ends. The machine pulls the sample at a constant rate until it breaks. Standard method such as ASTM D882 is used to calculate tensile strength.

[0061] Elongation measures how much a material can stretch before breaking, expressed as a percentage of its original length. It is also calculated using a standard method such as ASTM D882.

[0062] Table 2- Tensile strength and elongation

[0063] The new protective film layers PFL-1, PFL-2 and PFL-3 exhibit high elongation at lower tensile strength compared the Current-PFL and provide thereby improved flexibility for demanding applications in recesses.

[0064] Example 2: V-Panel Test

[0065] Lifting resistance of film material from recesses can be determined by the V-Panel Test.

[0066] A. Preparation of test panels

[0067] FIGS. 3A and 3B represent a schematic drawing of a test panel 1200, however not representing real measurements. The dimensions are given below. The test panel 1200 is formed from an aluminum sheet 1210 having a thickness of 1 mm that was bent to have a pattern of four successively deeper V-shaped grooves 1215 to 1218, each having different angles forming the V- shape and having different depths and length extensions.

[0068] After bending, the test panel has a dimension of 28 cm x 8.5 cm.

[0069] From the left to the right, the test panels have four grooves 1215 to 1218. Groove 1215 has a depth hl of 0.5 cm and a length extension 11 of 1.0 cm. The groove angles relative to the sheet metal plane are (left / right) al = 128° and al = 148°. Groove 1216 has a depth h2 of 1.0 cm and a length extension 12 of 2.0 cm. The groove angles relative to the sheet metal plane are (left / right) a3 = 118 ° and a4 = 147°. Groove 1217 has a depth h3 of 1.5 cm and a length extension 13 of 3.0 cm. The groove angles relative to the sheet metal plane are (left / right) a5 = 108° and a6 = 149°.

[0070] Groove 1218 has a depth h4 of 2.0 cm deep and a length extension 14 of 4.0 cm. The groove angles relative to the sheet metal plane are (left / right) al = 105° and a8 = 150°. All grooves extend entirely over the width of the metal sheet, i.e. have a width extension of 8.5 cm. The length extensions dl, d2, d3 and d5 are 3.5 cm. The length extension d4 is 4.0 cm. Untreated aluminum test panels were used and referred to in the examples as "Alu substrate". Some of the Al test panels were painted with a standard automotive paint used in the automotive industry and finally painted with a two-component Cerami Clear (CC) paint available from PPG, Pittsburgh, Pennsylvania, USA. After painting, the test panels were left at RT during 24 hours. The painted test panels are referred to in the examples as "CC substrate".

[0071] B. Application of film material on test panels

[0072] A strip of film material (8 cm x 30 cm) was applied on the test panel, using a squeegee, so the film was bridging the V-shaped grooves. The strip was heated at 50°C with a hot air gun and pressed in the grooves by means of a roll. The film material strip was then heated with the hot air gun until the substrate temperature reached 80°C (measured with an infrared thermometer). After heating, the film material strip was pressed into the grooves again using a small roll. The coated test panels were left at room temperature during 24 hours before heat treatment.

[0073] C. Lifting and removability of film material

[0074] The coated test panels were first visually evaluated. Then the test panels were heated in an oven at 70°C during 7 days after which the panels were cooled to room temperature and visually evaluated again.

[0075] After heat aging, the test panels were cooled to room temperature and the film material was manually removed at an angle of 45°.

[0076] Example 3: Bonding Force

[0077] The bonding force refers to the ability of a film or adhesive layer to stick or adhere tightly to a surface, providing resistance to separation or lifting. The bonding force can be determined according to ASTM D3330 methods.

[0078] Table 3- Bonding Force

[0079] Further, FIG. 4A, 4B, and 4C represent three PFLs on v-panel 1200, showing the lifting of the Current-PFL (FIG. 4C) compared to PFL-1 (FIG. 4A) and PFL-2 (FIG. 4B) on a test panel.

[0080] The figures demonstrate a direct relationship between bonding force and lifting resistance: PFL-2 (FIG. 4B) with the highest bonding force has the least lifting, while the Current-PFL (FIG. 4C) with the lowest bonding force shows the most lifting. Example 4: Optical Properties

[0081] Optical properties refer to how a material transmits and scatters light, affecting its clarity and transparency. Key metrics include transmission and haze, which determine the visual quality and clarity of the film. Transmission and haze can be measured according to ASTM D1003. methods.

[0082] Table 4: Optical properties of PFL

[0083] PFL-1, PFL-2 and PFL-3 show high transmission and low haze that do not impact the visual appearance of the color of the base film 100.

[0084] Example 5: Application of Film Material including PFL-1, PFL-2 and Current-PFL on vehicles

[0085] For the application on vehicles film material 1000 was prepared by laminating the protective film layers PFL-1, PFL-2 and Current-PFL each to the adhesive coated base film layer 600. For this test, adhesive coated base film layer of 3M Wrap Film 2080-G12 Gloss Black (commercially available from 3M Company of St. Paul, Minnesota, USA) was used.

[0086] Prior to the application, the release liner 300 was removed. Film Material without release liner 500 (protective film layer (PFL)), base film, adhesive layer) was then applied on a car hood and a van door using a squeegee with a buffer and a wrap glove.

[0087] Slideability of the squeegee with the buffer on both PFL-1 was higher compared to the Current-PFL. The higher slideability lowered the friction of each stroke and increased the speed of application with the squeegee. In addition, the wetting process of the squeegee buffer to lower the friction could be avoided and the squeegeeing could be done dry.

[0088] During application in the single recess of the van door, both PFL-1 and PFL-2 remained on the wrap film without lifting. Lifting occasionally occurred with the Current-PFL which made adjustment and repair work difficult, e.g. when trying to remove entrapped air bubbles in the recess.

[0089] With both PFL-1 and PFL-2, fewer surface defects, as e.g. craters, were seen on the wrap film surface compared to Current-PFL which is a significant improvement, and enhances customer’s satisfaction with Wrap Film Series 2080.

[0090] Example 6: Application of Film Material including PFL-3 and Current-PFL on vehicles

[0091] Film material 1000 was prepared by laminating the protective film layers PFL-3 and Current- PFL each to the adhesive coated base film layer 600. For this test, adhesive coated base film layer of 3M Wrap Film 2080-HG378 High Gloss Blue Raspberry (commercially available from 3M Company of St. Paul, Minnesota, USA) was used.

[0092] Prior to the application, the release liner 300 was removed. Film Material without Release Liner 500 (protective film layer, base film, adhesive layer) was then applied on a car hood and a van door using a squeegee with a buffer and a wrap glove.

[0093] Slideability of the squeegee of PFL-3 was higher compared to the Current-PFL. The higher slideability lowered the friction of each stroke and increased the speed of application with the squeegee. In addition, the wetting process of the squeegee sleeve to lower the friction could be avoided and the squeegeeing could be done dry.

[0094] During application in the single recess of the van door, the PFL-3, did not lift from the base film during application in the recesses whereas Current-PFL showed lifting from the base film as illustrated in FIG. 5A and FIG. 5B.

[0095] Peel force to remove PFL-3 from the base film surface was comparable to the Current-PFL, Matte, hazy areas on the PFL-3 induced by higher temperatures were not transferred to the base film surface compared to the Current-PFL In case of transfer as seen with the Current-PFL, matte areas on the base film surface became as expected glossy again with heat which suggests a change of surface roughness.

[0096] With the PFL-3 surface defects-were not seen on the base film surface.

[0097] Example 7: Dynamic coefficient of friction

[0098] Lower dynamic coefficient of friction of the PFL enhances the slideability of the squeegee with a buffer on the protective film layer and makes the application of the film easier and faster. Wetting of the squeegee with e.g. soapy water is not necessary anymore to provide good slideabillity.

[0099] The dynamic coefficient of friction can be determined by DIN EN ISO 8295:2004-10.

[0100] Table 5: Dynamic coefficient of friction of protective film layer The dynamic coefficient of friction was measured with PFL-3 and Current-PFL against the squeegee buffer 3M™ Blue Protection Buffer (commercially available from the 3M Company of St. Paul, Minnesota, USA) and against the wrap glove YelloGloves (commercially available from Yellotools GmbH, 51570 Windeck, Germany) at 100 mm / min. The lower dynamic friction coefficient of PFL-3 confirmed the higher slideability seen during application with the squeegee buffer on the vehicles of example 5.

[0101] Example 8: Matte, hazy spots after heat exposure

[0102] For the film application described in example 5, heat was used to enhance the conformability of the film. Applying heat with a hot air gun, matte, hazy spots on the Current-PFL appeared. When removing the Current-PFL, matte, hazy spots were also visible on the base film. These spots impacted the visual appearance of the base film surface and needed to be removed. With the PFL-3, less matte, hazy spots were visible. After removal of PFL-3 from the base film, the base film surface did not show matte, hazy spots that needed to be removed which would save working time for the installer.

[0103] Atomic force microscopy analysis (AFM analysis) showed that the matte hazy spots on the protective film layer were caused by a change of morphology and surface roughness induced by heat. With the Current-PFL the higher surface roughness after heat exposure transfers to the base film surface causing matte, hazy spots as well. The transfer is conceivable that elevations of the Current- PFL are leading to depressions on the base film surface. This effect was not given with PFL-3. Matte, hazy areas on PFL-3 were not transferred to surface of the base film as the change of morphology did not affect the surface of PFL-3 facing the base film surface.

[0104] Example 9: PFL

[0105] PFL is used on gloss and high Gloss Wrap Film Series 2080 to protect the film surface of the wrap film against manufacturing related surface impressions and against scratches caused by the squeegee (application tool) during the application process. The new PFL enhances the slideability of the squeegee on the surface of the protective film layer which makes the application of the Wrap Film 2080 easier and faster. Wetting of the squeegee with, for example, soapy water is not necessary anymore to provide sufficient slideability.

[0106] Due to a different chemistry, the new PFL has fewer defects and provides a better visual appearance of the wrap film surface after removal. The higher slideability of the squeegee on the new PFL is based on lower coefficient of friction at application speed compared to the currently used PFL from the supplier EPM. At least one layer consists of PE and LDPE while the layer facing the wrap film side contains an elastomeric polymer.

[0107] To address the melt fracture issue (surface deformation of the PFL during the extrusion process which leads to a rough surface appearance that later is transferred to the PVC film surface), Polifilm had modified the PFL chemistry of FC 48 / 39 by removing one component. That measure resulted in an improved surface appearance of 2080 High Gloss in terms of DOI and RIQ.

[0108] FIGS. 6A and 6B illustrate lower DOI and RIQ values of 2080 High Gloss film surface after removal of Polifilm PFL (EXP. M64 and EXP. M72) compared to Control PFL from EPM (Cntrl M64 and M72).

[0109] FIGS. 7A and 7B illustrate higher DOI and RIQ values of 2080 High Gloss film surface after removal of Polifilm PFL (PQ1 Lot 1 and PQ2+3 Lot 2) after resolution of the melt fracture issue and similar level compared to Control PFL from EPM (PQ1 -Cntrl and PQ2+3 Cntrl).

[0110] Table 6: Physical properties of the new PFL from Polifilm and PVC Film (2080 Gloss and High Gloss).

[0111] Reduction of matte, hazy spots after heat exposure: For the application of Wrap Film 2080, heat is used to enhance the conformability of the film.

[0112] Applying heat with a hot air gun, matte, hazy spots on the EPM PFL (Current-PFL) appeared. When removing the EPM PFL (Current-PFL), matte, hazy spots were also visible on the base film. These spots impact the visual appearance of the base film surface and need to be removed. With the PFL from Polifilm (PFL-3), less mate, hazy spots are visible after applying heat with a hot air gun compared to the EPM PFL (Current-PFL). After removal of the PFL from Polifilm (PFL-3) from the base film, the base film surface did not show mate, hazy spots. This features is illustrated in the photos of FIGS. 2A-2D. The present invention has now been described with reference to several embodiments thereof.

[0113] The entire disclosure of any patent or patent application identified herein is hereby incorporated by reference. The foregoing detailed description and examples have been given for clarity of understanding only. No unnecessary limitations are to be understood therefrom. It will be apparent to those skilled in the art that many changes can be made in the embodiments described without departing from the scope of the invention. Thus, the scope of the present invention should not be limited to the structures described herein, but only by the structures described by the language of the claims and the equivalents of those structures.

Claims

CLAIMS:

1. A film material (1000) comprising: a flexible base film (100) comprising a first surface (120) and an opposite second surface (140); an adhesive layer (200) comprising: a first surface (220) bonded to the second surface (140) of the base film; and an opposite second surface (240); a release liner (300) releasably attached to the second surface of the adhesive layer; and a protective film layer (400) with an adherent layer comprising a thermoplastic polymer, an elastomeric polymer or thermoplastic elastomer; releasably attached to the first surface of the flexible base film.

2. The film material (1000) of claim 1, wherein the adherent layer comprises a polymer adhesive selected from elastomer-based adhesives like polyisoprene, styrene block copolymers, styrene butadiene copolymers, polybutadiene, polyisobutylene and acrylic based adhesive such as C4-C11 polymer based.

3. The film material (1000) of claim 1, wherein the protective film layer has a dynamic coefficient of friction less than about 0.2 at a sled speed of 100 mm / min, with a wrap glove or a squeegee buffer.

4. The film material (1000) of claim 1, wound around a central longitudinal axis to form a cylindrical roll.

5. The film material (1000) of claim 1, wherein the flexible base film comprises at least one of a single layer polyvinylchloride (PVC) film, a double layer polyvinylchloride film, a triple layer polyvinylchloride film, a composite film, a polyester-based film, an acrylic-based film, a polyester film, a polypropylene film, a polyurethane film, and a polyolefin film.

6. The film material (1000) of claim 1, wherein the first surface of the flexible base film comprises a glossy surface, satin or matte surface.

7. The film material (1000) of claim 1, wherein the adherent layer of the protective film (400) has a bonding force in the range of about 2 to 20 cN / 25.4 mm, preferably in the range of 2 to 15 cN / 25 ,4mm and more preferably in the range of 2 to 6 cN / 25 ,4mm, measured at a separation speed of 2,286 mm / min.

8. The film material (1000) of claim 1, wherein the protective film layer comprises a multilayer construction with at least one layer comprising a thermoplastic elastomer or elastomeric polymer.

9. The film material (1000) of claim 8, wherein the thermoplastic polymers comprise polyethylene selected from the group consisting of linear low-density polyethylene (LLDPE), low- density polyethylene (LDPE), and high-density polyethylene (HDPE), elastomeric polymers including ethylene vinyl acetate copolymers, or thermoplastic elastomers including synthetic rubbers like styrene ethylene butadiene styrene block copolymer (SEBS).

10. The film material (1000) of claim 1, wherein the protective film layer is conformable and comprises an elongation that is the same or higher than an elongation of the base film.

11. The film material (1000) of claim 10, wherein the protective film layer has an elongation larger than 100 %.

12. The film material (1000) of claim 1, wherein the protective film layer is at least one of optically clear, transparent, translucent, and colored.

13. The film material (1000) of claim 1, wherein the protective film layer comprises a total visual transmittance of greater than 88%.

14. The film material (1000) of claim 1, wherein the protective film layer has a tensile strength in the range of about 5.0 to 40 N / mm2, preferably in the range of 10 to 30 N / mm2and more preferably in the range of 20 to 25 N / mm2.

15. The film material (1000) of claim 1, wherein the protective film layer has a thickness of less than 30 pm.

16. A sheet of film material (1000) of claim 1 comprising: a flexible base film (100) comprising a first surface (120) and an opposite second surface (140); an adhesive layer (200) comprising: a first surface (220) bonded to the second surface of the base film (140) and an opposite second surface (240); a release liner (300) releasably attached to the second surface of the adhesive layer; anda protective film layer (400) with an adherent layer comprising a thermoplastic polymer, an elastomeric polymer or a thermoplastic elastomer, releasably attached to the first surface of the flexible base film.

17. A method of applying a sheet of film material (1000) to a substrate, comprising the steps of: positioning a sheet of film material adjacent to an outer surface of a substrate, wherein the sheet of film material comprises: a flexible base film (100) comprising a first surface (120) and an opposite second surface (140); an adhesive layer (200) comprising: a first surface (220) bonded to the second surface of the base film (140); and an opposite second surface (240); a release liner (300) releasably attached to the second surface of the adhesive layer; and a protective film layer (400) with an adherent layer comprising a thermoplastic polymer, an elastomeric polymer or a thermoplastic elastomer, releasably attached to the first surface of the flexible base film; removing the release liner from the second surface of the adhesive layer; and applying the adhesive layer to the outer surface of the substrate.

18. The method of claim 17, further comprising the step of removing the protective film layer from the first surface of the film material before applying the adhesive layer to the outer surface of the substrate.

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