WO2020028633A1

WO2020028633A1 - Calendered polyvinyl chlorsde/cellulose ester blend film

Info

Publication number: WO2020028633A1
Application number: PCT/US2019/044617
Authority: WO
Inventors: Zachary Hoffman; Cornelia BOTHE
Original assignee: Klockner Pentaplast Of America, Inc.
Priority date: 2018-08-01
Filing date: 2019-08-01
Publication date: 2020-02-06
Also published as: WO2020028633A8

Abstract

The present invention generally relates to calendered films formed from a mixture of cellulose ester polymer, polyvinyl chloride polymer and one or more plasticizers. The inventive calendered films may further include any of a number of additives known in the art. The inventive films are suitable for use in a number of applications, including luxury vinyl tile and packaging.

Description

CALENDERED POLYVINYL CHLORIDE /CELLULOSE ESTER BLEND FILM

CROSS-REFERENCE TO RELATED APPLICTIONS

This application claims priority to United States Provisional Application 62/713,238, filed August 1, 2018, which is hereby incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates to more environmentally friendly calendered films.

Specifically, the present invention relates to calendered films incorporating cellulose ester.

BACKGROUND OF THE INVENTION

Polyvinyl chloride ("PVC") is extremely well known in the art and is used in an incredibly wide variety of applications, including vinyl flooring, vinyl siding, print graphics, pharmaceutical packaging, cards, labels and multi-layer constructions. Ture to its name, PVC is formed from vinyl chloride molecules, hence it contains high levels of chlorine. In addition, PVC also incorporates plasticizers that soften the resin and make is more flexible. Common plasticizers include phthalates and bisphenol A. Unfortunately, there are several potential environmental concerns regarding use of PVC, including the possible release of dioxins, phthalates and/or BP A, each of which may have a detrimental impact on the environment.

Building materials, particularly flooring and siding, represent two of the largest markets for PVC. Leadership in Energy and Environmental Design (LEED) is a world-wide rating system developed by industry experts to evaluate the environmental performance of building materials and the like and to encourage market transformation to more sustainable design, thus accelerating "green building practices". For example, under the LEED scoring system flooring containing a given amount of post-industrial recycle material and/or renewable materials are given preferences as "greener" products. Many federal, state and local governments have adopted LEED incentives, such as tax credits and tax exemptions for builders and home owners. Manufacturers are attempting to produce ever more environmentally friendly building materials that will aid in LEED certification. There thus remains a need in the art for PVC compositions or PVC substitutes that minimize or eliminate environmental concerns with conventional PVC.

The vinyl flooring industry is an especially large market for PVC, with PVC being the major component in all types of vinyl flooring, including vinyl tiles and luxury vinyl tile ("LVT"). LVT is a trade-term for a specific family of vinyl flooring that closely mimics the appearance of natural materials, such as wood or stone. Such appearance is accomplished by a layer having a very realistic photo-created image, combined with textures that resemble the image. LVT typically gamers a greater price than ordinary vinyl flooring, and consumers place a premium on LVT producers that are forward-thinking, particularly in regards to the improved environmental impact reflected by LEEDS certification. Accordingly, there remains a need in the art for LVT and other vinyl flooring with improved environmental performance.

More environmentally friendly polymers, such as bio-resins, particularly natural cellulose and modified-cellulosics, are generally known. Modified cellulose and regenerated cellulose are further known to exhibit a suitably low viscosity within specific cellulose-solvents, such as acetone for cellulose acetate or NMMO for cellulose, to allow the cellulose-solution to be extruded through either a flat die or the fine holes within a spinerette. Cellulose acetate is a well known in solution-spun fiber and tow extrusion, for example. Extruded blends containing natural cellulose are also known, as evidenced in United States Patent No. 6,784,230 to

Patterson, generally directed to extruded foams formed from chlorinated vinyl resin matrices incorporating wood fibers as a reinforcing filler. Such extrusion techniques typically involve extrusion through a manifold or die. In addition, cellulose ethers are known in coatings, particularly vinyl lacquers modified with cellulose acetate butyrate and acrylic resin are known.

Rather than extruded films or coatings, flooring is generally formed from calendered film. Calendering is known to be a more economic and highly efficient means to produce films ranging in thickness from about 2 mils (0.05 mm) to bout 45 mils (1.14 mm) relative to conventional extrusion. In calendaring, a series of large, heated, steel rollers transform a thick rope-shaped melt-blend into a thin, sheet-like film. Initially, a dry mixture of polymer and various additives are combined with plasticizer and subjected to sufficient heat, shear and pressure within a kneader or extruder to form the melt-blend. The melt-blend is then fed into two counter rotating heated rolls, commonly referred to as the mill, that applies pressure to flatten out the melt-blend. The milled melt-strip is then fed into multiple heated calender rolls that are arranged so as to form a series of nips whose gaps decrease as the melt-strip moves in the machine direction and ultimately forms the film. A number of thermoplastic polymers are known to be suitable as calendered film matrices, including PVC, polypropylene, and polyester, as noted within United States Patent No. 6,551,699 to Flynn. Furthermore, attempts have been made to produce more environmentally friendly calendered films based upon ethylene propylene copolymer incorporating starch or soy bio-resin, as described in United States Patent No.

8,592,501 to Phan et al. Although well known in the art for use in other enduses, such as fibers, cellulosic polymers have heretofore not been known to be a suitable matrix for calendering.

SUMMARY OF ADVANTAGEOUS EMBODIMENTS OF THE INVENTION

It is thus an object of the invention to provide a more environmentally friendly calendered film, particularly a more environmentally friendly calendered PVC film.

The foregoing object was achieved by forming calendered films from polymer matrices either including or consisting of a mixture of cellulose ester polymer and polyvinyl chloride polymer or cellulose ester alone. The inventive calendered films generally include cellulose ester polymer selected from one or more of cellulose acetate butyrate or cellulose acetate propionate and polyvinyl chloride or derivative thereof, along with at least one plasticizer. The present calendered films may further include any of a number of additives known in the calendering art, including one or more of filler(s); UV stabilizer(s); heat stabilizer(s); processing aid(s); lubricant(s); impact modifier(s); and colorant(s) and/or pigment(s).

The inventive films advantageously form one or more layers of a vinyl flooring laminate, particularly a luxury vinyl tile laminate used in flooring. An advantageous feature of the invention is the development of a calendered film layer that can be recycled back into the vinyl flooring production lines, thereby further benefitting the environment. Quite unexpectedly, Applicants have determined that cellulose ester and polyvinyl chloride blends incorporating cellulose ester can readily be formed into calendered films.

DETAILED DESCRIPTION OF ADVANTAGEOUS EMBODIMENTS OF THE INVENTION

The present invention now will be described more fully hereinafter in the following detailed description of the invention, in which some but not all inventive embodiments are described. The present invention may be embodied in many different forms and should not be construed as limited to the embodiments set form herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Furthermore, the present invention can include any combination of the various features set forth below, and any combination of disclosed features herein is considered part of the present invention and no limitation is intended with respect to combinable features. As used in the specification, and in the appended claims, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Similarly, the phrases "weight percent," "wt %" and/or "percent", relative to a component refers to the weight percentage of that component within the resulting film or film layer in which such component resides. All ranges include all integers subsumed therein, to the hundredth place.

Suitable cellulose ester matrices include any calenderable cellulose ester polymer, particularly any cellulose ester having a glass transition point, Tg, of less than or equal to about 170 °C, such as about 80 to 165 °C, particularly about 85 to about 161 °C. Suitable cellulose ester melting points typically range from about 125 to 240 °C, such as from about 127 to 175 °C. Exemplary cellulose ester viscosity typically ranges from about 0.035 to 80 poise, such as 0.038 to 76.00 poise, based on ASTM D1343 in the solution described in Formula A, ASTM D817. In that regard, higher viscosity grades of a particular ester are expected to impart a greater degree of film toughness and tensile strength to the resulting films and to exhibit higher melting points, as is known in the art. Typical cellulose ester number-average molecular weight, MW_n, generally ranges from about 12,000 to 75,000 dalton, based upon size exclusion chromatography.

Exemplary suitable cellulose esters include one or more of cellulose acetate butyrate, cellulose acetate propionate and derivatives thereof. In addition, a mixture of a single cellulose ester, such as mixture of higher and lower viscosity cellulose ester, is included within the inventive compositions, as well as blends of such a mixture with additional cellulose esters. The inventive cellulose esters may further be modified to increase their moisture resistance, for example by reacting at least a portion of the cellulose ester hydroxyls with isocyanate or amino resin or the like. The cellulose ester may have any particle size known in the art of dry blending, such as a mean particle size ranging from to 10 to 1000 pm, such as 100 to 750 pm, particularly from 200 to 500 pm.

The cellulose ester(s) may be incorporated into the inventive films in any effective amount, such as amounts ranging from about 0.1 to 80 wt %, particularly from about 25 to 75 wt %, and more specifically from about 40 to 60 wt %, based upon the total weight of the film.

Suitable polyvinyl chloride polymers as the vinyl matrix includes any calenderable polyvinyl chloride polymer or copolymer known in the art, including mixtures and derivatives thereof. PVC homopolymers are typically used, although PVC copolymers can also be incorporated in part or in total. Typical copolymers can include without limitation vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, vinyl chloride maleate and fumarate copolymers, vinyl chloride -olefin copolymers, vinyl chloride-acrylonitrile copolymers, and the like, and combinations thereof. In addition, the "polyvinyl chloride polymer" may be in the form of a single polymer or a blend further containing olefmic polymer, such as polypropylene, and the like. The PVC matrix may form either a continuous, solid matrices or a continuous foam layer.

Suitable PVC melt flows typically range from about K56 to K70, particularly K60 to K70, translating into inherent viscosities ranging from about 0.63 to 1.60 dl/g, such as 0.78 to 1.40 dl/g, as measured by ASTM-D-1243-60A. The PVC raw material may have any suitable mean particle size for dry blending, such as a particle size ranging from about 0.2 to 200 pm, preferably from 0.2 to 50 pm.

The polyvinyl chloride may be incorporated into the inventive films in any effective amount, such as amounts ranging from about 0.1 to 80 wt %, particularly from about 25 to 75 wt %, and more specifically from about 40 to 60 wt %, based upon the total weight of the film.

In alternative embodiments, alternative calenderable polymers may be

incorporated in lieu of or in addition to the PVC. Exemplary alternative calenderable polymers include polyolefins, particularly talc-filled polypropylene, as well as polyesters, particularly polyesters having delayed crystalline half-lives, as well as thermoplastic rubbers, acrylonitrile/butadiene/styrene terpolymers (ABS resins) and chlorinated

polyethylene.

As noted above, the foregoing polymer blend, e.g. the PVC/cellulose ester blend, may further include any of a number of ingredients or additives known in the art,

including plasticizers to impart fluidity, stabilizers to prevent thermal degradation; impact modifiers, modifiers for clarity, heat stability or opacity characteristics; colorants and/or pigments; lubricants and processing aids; anti-static agents; UV inhibitors; moisture barriers and flame retardants.

The inventive films incorporate at least one plasticizer. Although a single

plasticizer may be used to plasticize both the PVC and cellulose ether, the inventors have found it more advantageous to incorporate a mixture of plasticizers whose components are specifically selected to impart sufficient flexibility for calenderability to the cellulose ether and PVC matrices, respectively.

Consequently, the inventive films can theoretically include any plasticizer known in the art of cellulose esters as a first plasticizer. In expedient embodiments, Applicants have determined that one or more of di-octyl terephthalate; di-octyl adipiate ("DOA");

triethylene glycol bis 2-ethylhexanoate ("TEG-EH") or derivatives thereof can be used as a first plasticizer to plasticize the cellulose-ether component sufficiently for calenderaing.

In particularly advantageous embodiments, di-octyl adipiate or triethylene glycol bis 2- ethylhexanoate, especially DOA, is incorporated as the first plasticizer. In that regard, the inventors have found that DOA and TEG-EH plasticizers are more efficient than di-octyl terephthalate for cellulose ether calendering.

The first plasticizer (i.e. the cellulose ether plasticizer) may be present in any amount effective to plasticize the cellulose ether, such as from about 0.1 to 30 wt % particularly from about 5 to 25 wt %, more particularly from about 10 to 20 wt %, based on the weight of the cellulose ether.

The inventive films can similarly theoretically include any plasticizer or mixture thereof known in the art of polyvinyl chloride calendering as the second plasticizer. The inventive films typically include one or more of mono-, di or tri-esters of mono-, di-, or tri- carboxylic acids or phosphoric acid plasticizer, such as phthalates, i.e. dioctyl phthaltate (particularly dioctyl terephthalate), adipates, i.e. dioctyl adipate, trimellittes, i.e. trioctyl trimellitate, and the like and combinations thereof. In the alternative, the inventive films may include low extractable plasticizers as either all or part of the second plasticizer. Exemplary low extractable plasticizers include higher molecular weight plasticizers, such as polymeric plasticizers or butyl benzyl phthatlate coester, as described in published United States Patent Application No. 2099/0288359, which is hereby incorporated herein. In particularly advantageous embodiments, the second plasticizer includes or consists of dioctyl terephthalate.

The second plasticizer may be present in any amount effective to plasticize the polyvinyl chloride, such as from about 0.1 to 30 wt %, particularly from about 5 to 25 wt %, more particularly from about 10 to 20 wt %, based on the weight of the polyvinyl chloride.

Nonlimiting exemplary fillers that may be incorporated within the inventive calendered films include particulates formed from one or more of calcium carbonate, talc, kaolin, mica and glass, each of which may optionally further comprise a coating or surface treatment, as known in the art. In alternative embodiments, the inventive films may include cellulose fiber and/or cellular filler as described United States Patent No. 4,510,201, which is hereby incorporated by reference. As a further alternative, other fibrous material, such as polyester fiber or the like, may be included as filler, as described in United States Published Patent Application No. 2009/0288359, hereby incorporated by reference herein. Suitable filler diameters include any mean particle diameter known in the art of calendaring, such as 0.5 to 4 pm filler, particularly 1 to 2 pm filler. The filler can be present in any effective amount known in the art, such as from about 0 to 20 wt %, specifically from about 5 to 15 wt %.

UV stabilizer is typically included within the inventive films. Any UV stabilizer and/or opacifier known in the art of calendaring may be incorporated into the inventive films, including one or more of titanium dioxide, benzophenone UV absorbers and hindered amine light stabilizers. Advantageously, titanium dioxide is incorporated as the UV stabilizer and/or opacifier. The UV stabilizer can be present in any effective amount known in the art, such as from about 0 to 15 wt %, specifically from about 5 to 10 wt %.

Flexural modulus modifiers may also be incorporated into the inventive films.

Any known flexural modulus modifier known in the art of calendered films may be incorporated, including one or more of talc, polymethyl methacrylate or other polymeric flexural modifiers, and ultrafine modifiers (average particle size less than 0.1 microns). The flexural modulus modifier may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 20 wt %, and more specifically from about 5 to 15 wt %.

During processing in the melt state at elevated temperatures, PVC tends to degrade. Consequently, the inventive films expediently incorporate one or more heat stabilizers known in the calendaring art. Exemplary heat stabilizers include one or more mixed metal stabilizers, such as calcium-zinc compounds, barium-zinc compounds, cadmium-barium-zinc compounds, lead compounds, tin compounds and derivatives thereof, which can function as primary heat stabilizers. In particularly beneficial embodiments, the stabilizer is a calcium zinc stabilizer, such as CT341P from Baerlocher GmbH. In addition to the primary heat stabilize^ s) the inventive films can include a secondary heat stabilizer, such as expoxidized soybean oil or the like, which can also function as a secondary PVC plasticizer. The heat stabilizer may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 6 wt %, and more specifically from about 2 to 4 wt %.

Processing aids modify the PVC rheology, imparting improved fusion properties and more homogeneous melts, inter alia. Exemplary processing aids include any processing aid known in the art of calendaring, such processing aids comprising one or more of acrylic (also referred to in the art as "all-acrylic"), acrylic-styrene and poly(a- methyl) styrene. In expedient embodiments, the processing aid is PARALOID^® K175 or K120 acrylic processing aid from Dow Chemical Co.

The processing aid may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 6 wt %, and more specifically from about 2 to 4 wt %.

The inventive films may also include one or more of either an internal or external lubricant. Internal lubricants reduce friction occuring between the molecular chains of PVC, thus lowering the melt viscosity. External lubricants mainly reduce adhesion between the PVC and metal processing surfaces. Exemplary external lubricants include any external lubricant known in the art of calendaring, such as one or more of montan wax and/or esters thereof, amide wax, polyethylene wax, polypropylene wax, modified hydrocarbon wax and soya bean oil wax (a renewable wax). In expedient embodiments, the lubricant is montan wax, an external lubricant. Suitable PVC lubricants are available from a wide range of commercial suppliers, including Clariant Corporation.

The external and/or internal lubricants aid may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 5 wt %, and more specifically from about 2 to 4 wt %.

Impact modifiers may also be employed within the inventive films. Exemplary impact modifiers include any impact modifier known in the art of calendaring, such as one or more of all-acrylic, methacrylate butadiene styrene, methacrylate acrylonitrile butadiene styrene, and modified acrylic. Acrylic impact modifiers, such as FM-80 from Kaneka Corp., are particularly useful in the present invention. The impact modifier aid may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 15 wt %, and more specifically from about 5 to 10 wt %.

Exemplary colorant/pigment include any colorant/pigment known in the art of calendaring, such as one or more of titanium dioxide, zinc oxide and carbon black.

Suitable colorant/pigment median diameters include any known in the art, such as median diameters ranging from 1 to 2 pm.

The colorant/pigment may be included in any effective amount known in the art of calendaring, such as an amount ranging from about 0 to 25 wt %, and more specifically from about 1 to 20 wt %.

Secondary additives that may be incorporated within the inventive films include one or more of flame retardants, antimicrobials, mildewcides, antioxidants, and the like.

Any secondary additive can be added in any effective amounts known in the art, such as from 0 to 30 wt % more specifically 10 to 20 wt %.

The inventive films may have any overall or layer thickness known in the calendered film art, particularly the luxury vinyl tile art. Generally, the inventive films have a thickness ranging between about 60 to 1000 pm, such as between about 70 to 600 pm.

The inventive films exhibit adequate physical properties for use as a calendered film, particularly as a luxury vinyl tile. For example, the inventive films typically exhibit tensile strengths ranging from 20 to 35 N/mm², such as from 25 to 30 N/mm² (as determined via ASTM D882) and modulus of elasticity ranging from 500 to 2000 MPa, such as a modulus of 750 to 1500 MPa (as determined via ASTM D882). The optical properties of the inventive films are likewise suitable for use within at least the luxury vinyl tile market. The opacity of the inventive films generally ranges from 50 % to 99 % , such as from 60 to 80 % opacity. The inventive films can be formed by any calendaring process known in the art. In an exemplary calendering process, the polymer(s), e.g. PVC and cellulose ether, are weighed and blended as dry powders in a mixer, along with the first and second plasticizers, optional UV stabilizer; optional heat stabilizer; optional processing aid; optional lubricant; optional impact modifier; and optional colorant and/or pigment to form a dry blend. After mixing, the foregoing ingredients are plasticized in a kneader or extruder to form a melt blend. In alternative embodiments, a plastisol may be used in lieu of a dry blend.

In melt blending, the dry powders are fused to form a homogeneous, molten material by applying heat, shear and pressure. The inventors have found that sufficient shear and/or a longer kneading period are highly beneficial in breaking down cellulose ether particles or clumps prior to calendaring. The melt blended composition typically exits the kneader or extruder as a single thick, rope-like molten strand or melt blend. This melt blended molten material is directly fed in a continuous process to the top of a mill bin, such as a two-roll mill bin, where it is rolled into an initial sheet-film. The sheet-film is then formed into a calendered film via a calendaring stack. Typically, four calendering rolls are used to form three nips or gaps within a calendaring stack. The calender rolls may be any configuration; however, they are usually configured in an“L” shape or an inverted“L” shape. The rolls vary in size to accommodate different film widths. The rolls have separate temperature and speed controls. The melt blend proceeds through the nip between the first two rolls, referred to as the feed nip. The rolls rotate in opposite directions to help spread the material across the width of the rolls. The material winds between the first and second, second and third, third and fourth rolls, etc. The gap between rolls decreases in thickness between each of the rolls so that the material is thinned between the sets of rolls as it proceeds. After passing through the calender section, the material moves through another series of rolls where it is optionally stretched and/or embossed with one or more patterns or to impart gloss, then gradually cooled via chill rolls within a cooling section to form the calendered film or sheet. The cooled calendered film is then wound onto master rolls.

The inventive calendered films are suitable for use in a wide variety of applications, including vinyl tile for floor (particularly luxury vinyl tile), wall coverings and packaging (such as pharmaceutical packaging). In expedient embodiments, the inventive films form one or more layers a vinyl tile laminate, particularly a luxury vinyl tile laminate.

As with conventional vinyl tile, luxury vinyl tile typically includes at least 4 layers: an aluminum oxide layer, a clear film layer, a design layer, an optional fill layer and a backing layer. The aluminum oxide layer is the topmost layer and prevents light scratching and shoe scuffs. The clear film layer, also referred to as the wear layer, protects against harder damage, such as rips and tears. The design layer is a photo-realistic print of stone or wood on either a paper or film substrate. The optional fill layer provides stability and indention resistance. The backing layer, which is the bottom layer disposed adjacent the floor underlayment and typically forms 90% of the product thickness, imparts noise resistance, flooring structure and solidity. Luxury vinyl tile generally ranges in overall thickness from about 10 mm to 20 mm.

In advantageous embodiments, the inventive films is used to form the printed, fill and/or backing layer. The thickness for inventive films for use as a backing layer generally range in thickness from about 9 to 18 mm. The thickness for inventive films suitable for use as a design layer substrate generally range in thickness from about 0.06 mm to 0.80 mm. In especially beneficial embodiments, the inventive film surface to be printed may be surface treated and/or coated to promote ink adhesion using methods, such a corona treatment, and coatings, such as acrylic coatings, known in the film art. In further inventive aspects, inventive films containing minimal (e.g. 1 % or less) or no PVC may exhibit a sufficiently minimal haze to be suitable for use as a wear layer. Luxury vinyl tile typically includes a thicker wear layer than conventional vinyl flooring, with wear layers typically ranging from about 0.1 to 6.5 mm, such as from about 2 to 4 mm. The inventive calendered films may further be surface treated and/or coated on one or more sides to promote interlaminar adhesion, adhesion to printing inks, release properties or the like.

Applicants have determined that the inventive films containing cellulose esters are recyclable. Specifically, the inventive laminates may be recycled back into one or more of the production lines for the various LVT layers. When a LVT film construction is laminated, trims of the entire construction (several layers) are taken and then recycled back in to the film manufacturing process to produce a balance, or backing, layer for the same LVT construction. Advantageously, the LVT backing (or fill layer or other layer) may contain up to 10 wt %, such as from 4 to 6 wt %, of recycled inventive film. Such recycling provides an environmentally friendly option for disposal of off trimmings, such as edge trim and the like.

Luxury vinyl tile incorporating the inventive film can be cut into any size known in the LVT art, such as squares or rectangular pieces. Exemplary square articles include 12 or 16 inch squares. Exemplary rectangular pieces may feature an interlocking design, with common dimensions being 7" x 48" or the like.

Further potential advantages imparted by the inventive calendered films include improved adhesion and compatibility between independent PVC and cellulose ester layers in multilayer constructions for flooring, pharmaceuticals, etc, where PVC typically cannot laminate independently (i.e. without adhesives) to cellulose ethers. PVC/cellulose ether blends provides economic benefits over standard cellulose ether products alone, including recyclability within a manufacturing process that handles both PVC and CE materials, including the reuse of mixed waste streams. The blend of the two polymers may provide an improvement over either individual polymer, depending on the application. For example, the PVC component imparts superior abrasion resistance, wear resistance, flame retardation and barrier properties, while the cellulose ether component may impart environmental sustainability, heat resistance, and improved UV protection,

As used herein, the term "matrix" or "matrices" refers to a continuous phase or continuous film in which fillers, additives and/or reinforcements may be dispersed and/or dissolved.

Additional advantages, features and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices, shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. Example 1

75 g of cellulose acetate propionate (CAP -482-20 from Eastman Co., T_m of 199 °C) was added to a mixer. 20 g of di-octyl adipate plasticizer was added to the CAP, and stirred for3 minutes. The plasticized CAP was then fed to a two roll mill at a temperature of 330 to 360 °F. Using a tight nip between the two rolls on the mill, i.e. less than 300 pm, broke down the majority of cellulose ester particles, resulting in a clear, haze-free 508 gauge film.

Example 2

37.5 g of cellulose acetate propionate resin (CAP-482-20 from Eastman Co., T_m of 199 °C) and 42 g of PVC (K60 from Shintech Inc) resin were added to a mixer. 10 of di-octyl adipate plasticizer and 10 g of di-octyl terephalate were added to the resin mixture and stirred for 3 minutes.

Claims

THAT WHICH IS CLAIMED:

1. A calendered film comprising:

from about 0.1 to 80 wt % of a cellulose ester;

from about 0.1 to 80 wt % of polyvinyl chloride,

from about 0.1 to 30 wt % of a cellulose ether plasticizer as a first

plasticizer;

from about 0.1 to 30 wt % of a polyvinyl chloride plasticizer as a second plasticizer;

from about 0 to 40 wt % of a filler;

from about 0 to 20 wt % of a flexural modulus modifier;

from about 0 to 2 wt % of a UV stabilizer;

from about 0 to 6 wt % of a heat stabilizer;

from about 0 to 6 wt % of a processing aid;

from about 0 to 6 wt % of a lubricant;

from about 0 to 15 wt% of an impact modifier; and

from about 0 to 20 wt % of a colorant and/or pigment,

with each of the foregoing wt % based on the weight of the film.

2. The film as claimed in Claim 1, wherein the cellulose ester comprises one or more of cellulose acetate butyrate or cellulose acetate propionate,

3. The film as claimed in Claim 1, wherein the cellulose ester is present in an amount ranging from about 25 to 75 wt %.

4. The film as claimed in Claim 1, wherein the cellulose ester has an IV ranging from about 0.035 to 80 poise, based on ASTM D1343.

5. The film as claimed in Claim 1, wherein the first plasticizer is selected from either di-octyl adipate, triethylene glycol bis 2-ethylhexanoate or mixtures thereof.

6. The film as claimed in Claim 1, wherein the first plasticizer is present in an amount ranging from about 10 to 20 weight percent.

7. The film as claimed in Claim 1, wherein the PVC exhibits a melt flow from about K

K56 to K70.

8. The film as claimed in Claim 1, wherein the PVC is present in an amount ranging from about 25 to 75 wt %.

9. The film as claimed in Claim 1, wherein the second plasticizer is one or more of mono-, di or tri-esters of mono-, di-, or tri- carboxylic acids or phosphoric acids.

10. The film as claimed in Claim 1, wherein the second plasticizer is present in an amount ranging from about 10 to 20 wt %.

11. The film as claimed in Claim 1, wherein the filler is selected from one or more of calcium carbonate, talc, kaolin, mica and glass.

12. The film as claimed in Claim 1, wherein the flexural modulus modifier is selected from one or more of talc, polymethyl methacrylate, polymeric flexural modifier other than polymethyl methacrylate, and ultrafme calcium carbonate.

13. The film as claimed in Claim 1, wherein the UV stabilizer is selected from titanium dioxide, benzophenone UV absorbers and hindered amine light stabilizers.

14. The film as claimed in Claim 1, wherein the heat stabilizer is selected from one or more of calcium-zinc compounds, barium-zinc compounds, cadmium-barium-zinc compounds, lead compounds and tin compounds.

15. The film as claimed in Claim 1, wherein the processing aid is selected from one or more of acrylic, acrylic-styrene and poly(a-methyl) styrene processing aids.

16. The film as claimed in Claim 1, wherein the lubricant is selected from one or more of montan wax, amide wax, polyethylene wax, polypropylene wax, modified hydrocarbon wax and soya bean oil wax.

17. The film as claimed in Claim 1, wherein the impact modifier is selected from one or more of acrylic, methacrylate butadiene styrene, methacrylate acrylonitrile butadiene styrene, and modified acrylic impact modifiers.

18. The film as claimed in Claim 1, wherein the colorant and/or pigment is selected from titanium dioxide, zinc oxide and carbon black.

19. A laminate comprising a film as claimed in Claim 1, wherein said laminate is selected from luxury vinyl flooring, wall covering, and packaging.

20. A process of manufacturing a film as claimed in claim 1 comprising:

weighing and subsequently blending effective amounts of cellulose ester;

polyvinyl chloride; cellulose ether plasticizer; polyvinyl chloride plasticizer; optional filler; optional flexural modulus modifier, optional UV stabilizer; optional heat stabilizer; optional processing aid; optional lubricant; optional impact modifier; and optional colorant and/or pigment to form a dry blend;

plastifying the dry blend into a melt blend;

rolling the melt blend in a two-roll mill bin to form a sheet-film;

calendering the sheet-film into a calendered film via a calendaring stack;

optionally embossing the calendered film with one or more patterns or to impart gloss;

passing the optionally embossed calendedered film through chill rolls in a cooling section; and

taking up the cooled calendered film on a roll.