TWI766003B - Multilayer films containing a slip agent - Google Patents

Abstract

The present disclosure provides a multilayer film containing at least three layers, including (A) a core layer containing a high density polyethylene (HDPE) having a density from 0.940 g/cc to 0.980 g/cc; and (B) skin layers on opposite sides of the core layer. Each skin layer includes (i) a propylene homopolymer; (ii) from 2,000 to 3,500 ppm of a slip agent; and (iii) from 4,000 to 10,000 ppm of an antiblock agent.

Description

Multilayer film with slip agent

The present invention relates to multilayer films containing slip agents.

Film layers formed from polyolefins are used in confectionery packaging, and in particular twist packaging for wrapping confectionery. Multilayer film twist packaging requires a balance of: (i) high torsion retention to maintain wrap form, (ii) low coefficient of friction (COF) (eg, at or below 0.38) to improve multi-layer film machining, and (iii) ) low yield tension (eg, below 16 MPa) to enable the multilayer film to permanently deform and maintain folding/torsion by the lower tension applied to the multilayer film. However, polyolefin film layers typically exhibit poor torsion retention, high COF and high One or more of the regional service tensions.

The art recognizes the need for a multilayer film having a skin layer containing a polyolefin that exhibits low COF, high torsional retention, and low yield tension.

The present invention provides a multilayer film comprising at least three layers, comprising: (A) a core layer comprising high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc; (B) between said core layer Skin layers on opposite sides, each skin layer comprising (i) propylene homopolymer; (ii) 2,000 to 3,500 ppm slip agent; and (iii) 4,000 to 10,000 ppm anti-caking agent.

The present invention provides multilayer films. In one embodiment, the multilayer film contains at least three layers comprising (A) a core layer comprising high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc; and (B) on opposite sides of the core layer upper surface. Each skin layer contains (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; and (iii) 4,000 to 10,000 ppm of anti-caking agent. A. Core layer

The multilayer film contains a core layer. The core layer contains high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc.

"High Density Polyethylene" (or "HDPE") is an ethylene homopolymer or ethylene/α-olefin copolymer with at least one C4-C10 α-olefin comonomer or C8 α-olefin comonomer and having a density of 0.940 g/cc, or 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc, or 0.958 g/cc to 0.960 g/cc, or 0.962 g/cc, or 0.965 g/cc, or 0.970 g/ cc, or 0.975 g/cc, or 0.980 g/cc. In one embodiment, the HDPE has a density greater than 0.940 g/cc, or 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc, or 0.958 g/cc to 0.960 g/cc, or 0.962 g/cc , or 0.965 g/cc, or 0.970 g/cc, or 0.975 g/cc, or 0.980 g/cc. HDPE can be a unimodal copolymer or a multimodal copolymer. A "unimodal ethylene copolymer" is an ethylene/ _C4 - _C10 alpha-olefin copolymer having one distinct peak in gel permeation chromatography (GPC) exhibiting molecular weight distribution. A non-limiting example of a suitable unimodal HDPE is AXELERON™ FO 6318 BK CPD, available from The Dow Chemical Company. A "multimodal ethylene copolymer" is an ethylene/ _C4 - _C10 alpha-olefin copolymer having at least two distinct peaks in GPC exhibiting molecular weight distribution. Multimodal includes copolymers with two peaks (bimodal) as well as copolymers with more than two peaks. Non-limiting examples of suitable multimodal HDPEs include DOW™ high density polyethylene (HDPE) resins (available from The Dow Chemical Company), ELITE™ reinforced polyethylene resins (available from The Dow Chemical Company), CONTINUUM™ dual Peak polyethylene resins (available from The Dow Chemical Company), LUPOLEN™ (available from LyondellBasell), and HDPE products from Borealis, Ineos and ExxonMobil.

In one embodiment, the HDPE comprises greater than 50 wt%, or 55 wt%, or 60 wt%, or 65 wt% to 70 wt%, or 75 wt%, or 80 wt%, or 85 wt%, based on the total weight of HDPE wt%, or 90 wt%, or 95 wt%, or 97 wt%, or 99 wt%, or 100 wt% of units derived from ethylene and inverse amounts or 0 wt%, or 1 wt%, or 3 wt%, or 5 wt%, or 10 wt%, or 15 wt%, or 20 wt%, or 25 wt%, or 30 wt% to 35 wt%, or 40 wt%, or 45 wt%, or less than 50 wt% source in comonomer units.

In one embodiment, the HDPE has a melt index (MI) of 0.1 g/10 min, or 0.5 g/10 min to 1.0 g/10 min, or 1.5 g/10 min, or 2.0 g/10 min. In another embodiment, the HDPE has a melt index (MI) of 0.1 g/10 min to less than 2.0 g/10 min.

In one embodiment, the HDPE has one, some or all of the following properties: (i) a density of 0.940 g/cc, or 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc, or 0.958 g/cc cc to 0.960 g/cc, or 0.962 g/cc, or 0.965 g/cc, or 0.970 g/cc, or 0.975 g/cc, or 0.980 g/cc; and/or (ii) a melt index (MI) of 0.1 g/10 min, or 0.5 g/10 min to 1.0 g/10 min, or 1.5 g/10 min, or 2.0 g/10 min; and/or (iii) greater than 50 wt% based on the total weight of HDPE, or 55 wt%, or 60 wt%, or 65 wt% to 70 wt%, or 75 wt%, or 80 wt%, or 85 wt%, or 90 wt%, or 95 wt%, or 97 wt%, or 99 wt%, or 100 wt% of units derived from ethylene, and the opposite amount, or 0 wt%, or 1 wt%, or 3 wt%, or 5 wt%, or 10 wt%, or 15 wt%, or 20 wt% %, or 25 wt%, or 30 wt% to 35 wt%, or 40 wt%, or 45 wt%, or less than 50 wt% of units derived from comonomers.

In one embodiment, the HDPE has at least 2 or all 3 of properties (i)-(iii).

In one embodiment, HDPE is an ethylene homopolymer. In another embodiment, HDPE is an ethylene homopolymer having a density of 0.962 g/cc and a melt index of 0.85 g/10 min. In another embodiment, the HDPE is ELITE™ 5960G available from The Dow Chemical Company.

In one embodiment, the core layer contains 80 wt%, or 85 wt%, or 90 wt%, or 95 wt% to 97 wt%, or 98 wt%, or 99 wt%, or 98 wt%, or 99 wt%, based on the total weight of the core layer. 100 wt% HDPE.

In one embodiment, the core layer includes optional additives. Non-limiting examples of suitable additives include antioxidants, antistatic agents, stabilizers, nucleating agents, colorants, ultraviolet (UV) absorbers or stabilizers, flame retardants, compatibilizers, plasticizers, fillers , processing aids, crosslinking agents such as peroxides, and combinations thereof.

In one embodiment, the core layer does not include antiblock and/or slip agents.

In one embodiment, the core layer contains from 80 wt%, or 85 wt%, or 90 wt%, or 95 wt% to 97 wt%, or 98 wt%, or 99 wt%, or 98 wt%, or 99 wt%, based on the total weight of the core layer. 100 wt% HDPE, and 0 wt%, or 0.01 wt%, or 0.05 wt%, or 0.1 wt%, or 0.2 wt% to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive.

In one embodiment, the core layer consists essentially of or consists of 80 wt %, or 85 wt %, or 90 wt %, or 95 wt % to 97 wt %, or 98 wt %, based on the total weight of the core layer wt%, or 99 wt%, or 100 wt% HDPE, and 0 wt%, or 0.01 wt%, or 0.05 wt%, or 0.1 wt%, or 0.2 wt% to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive.

HDPE can be the only polymeric component in the core layer, or HDPE can be present in a blend with one or more polymeric components combined with HDPE. Non-limiting examples of suitable polymeric components are polyolefins, such as ethylene-based polymers or propylene-based polymers. The optional polyolefin is different from HDPE. However, it should be understood that the core layer may comprise a blend of two or more different HDPEs. In one embodiment, the core layer does not include an optional polyolefin. In another embodiment, the core layer does not include a propylene-based polymer.

The core layer has two opposing surfaces. In one embodiment, the core layer is a continuous layer having two opposing surfaces.

In one embodiment, the thickness of the core layer is 6.0 µm, or 7.0 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 16.0 µm, or 17.0 µm, or 18.0 µm, or 19.0 µm, or 19.8 µm to 22.2 µm, or 23.0 µm, or 25 µm, or 30 µm, or 35 µm, or 40 µm, or 45 µm, or 50 µm , or 65 µm, or 70 µm, or 75 µm, or 80 µm, or 85 µm, or 90 µm.

The core layer may include two or more of the embodiments disclosed herein. B. surface layer

The multilayer film contains skin layers on opposite sides of the core layer. Each skin layer contains (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; (iii) 4,000 to 10,000 ppm of anti-caking agent; and (iv) additives as appropriate.

In one embodiment, each skin layer consists essentially of or consists of: (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; (iii) 4,000 to 10,000 ppm of anti-caking agent; and Optional (iv) Additives.

In one embodiment, each surface layer has a thickness of 0.75 µm, or 1.0 µm, or 1.5 µm, or 2.0 µm, or 3.0 µm, or 4.0 µm, or 5.0 µm, or 6.0 µm, or 6.5 µm to 7.0 µm, or 7.5 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 20.0 µm, or 25.0 µm, or 30 µm. The skin layers can have the same thickness or different thicknesses.

The skin layer may include two or more than two embodiments disclosed herein. i. Propylene homopolymer

Each surface layer contains a propylene homopolymer. The propylene homopolymer contains 100 wt% units derived from propylene.

Propylene homopolymers are voids of comonomers such as ethylene. In one embodiment, the propylene homopolymer consists of propylene and optional additives.

A non-limiting example of a suitable propylene homopolymer is CUYOLEN™ 1102L available from Petroquimica Cuyo S.A.I.C.

In one embodiment, the propylene homopolymer has a melt flow rate (MFR) of 2.0 g/10 min, or 3.0 g/10 min, or 4.0 g/10 min to 5.0 g/10 min, or 6.0 g/10 min min, or 7.0 g/10 min, or 8.0 g/10 min, or 9.0 g/10 min, or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min . In one embodiment, the propylene homopolymer has a melt flow rate (MFR) of greater than 2.0 g/10 min to 25 g/10 min, or greater than 2.0 g/10 min to 15.0 g/10 min, or 2.5 g/ 10 min to 6.0 g/10 min.

In one embodiment, the propylene homopolymer has a density of 0.900 g/cc, or 0.902 g/cc, 0.903 g/cc, or 0.904 g/cc to 0.906 g/cc, or 0.908 g/cc.

In one embodiment, the melting temperature Tm of the propylene homopolymer is 155°C, or 157°C, or 159°C to 161°C, or 163°C, or 165°C.

In one embodiment, the propylene homopolymer has one, some or all of the following properties: (i) MFR of 2.0 g/10 min, or 3.0 g/10 min, or 4.0 g/10 min to 5.0 g/10 min , or 6.0 g/10 min, or 7.0 g/10 min, or 8.0 g/10 min, or 9.0 g/10 min, or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min; and/or (ii) a density of 0.900 g/cc, or 0.902 g/cc, 0.903 g/cc, or 0.904 g/cc to 0.906 g/cc, or 0.908 g/cc; and/ or (iii) the melting temperature Tm is 155°C, or 157°C, or 159°C to 161°C, or 163°C, or 165°C.

In one embodiment, the propylene homopolymer has at least 2 or all of properties (i)-(iii).

In one embodiment, the propylene homopolymer has a melt flow rate (MFR) of 5.0 g/10 min, a density of 0.903 g/cc and/or a melting point of 161°C. In another embodiment, the propylene homopolymer is CUYOLEN™ 1102L, available from Petroquimica Cuyo S.A.I.C.

In one embodiment, each skin layer contains from 70 wt%, or 75 wt%, or 77 wt% to 80 wt%, or 83 wt%, or 85 wt%, or 90 wt%, based on the total weight of each skin layer, or 95 wt%, or 96 wt%, or 97 wt%, or 98 wt%, or 99 wt%, or 99.3 wt%, or 99.4 wt%, or less than 100 wt% propylene homopolymer.

The propylene homopolymer may include two or more than two of the embodiments disclosed herein. ii. Slip agent

Each surface layer contains a slip agent. A "slip agent" is a compound having a coefficient of friction (COF) of 0.02 to 0.15. In one embodiment, the slip agent has a COF of 0.02, or 0.04, or 0.06, or 0.07, or 0.08, or 0.09, or 0.10 to 0.15.

Non-limiting examples of suitable slip agents include fatty acid amides, polysiloxanes, plasticizers, organic amines, dibasic esters, stearates, sulfates, fatty acids, mineral oils, vegetable oils, fluorinated organic resins, Graphite, tungsten disulfide, molybdenum disulfide, and combinations thereof.

結構（I） 其中R為C₃ 至C₂₇ 烷基部分。在一個實施例中，R為C₁₁ 至C₂₅ ，或C₁₅ 至C₂₃ 烷基部分。在另一實施例中，R為C₂₁ 烷基部分。 R可為飽和、單不飽和或多不飽和。在一個實施例中，R為單不飽和。適合之脂肪酸醯胺之非限制性實例包含芥酸醯胺（erucamide）、油醯胺、棕櫚醯胺（palmitamide）、硬脂醯胺及山崳酸醯胺（behenamide）。此外，脂肪酸醯胺可為兩種或多於兩種脂肪酸醯胺之混合物。在一個實施例中，脂肪酸醯胺為芥酸醯胺。In one embodiment, the slip agent is a fatty acid amide. A "fatty acid amide" is a molecule with structure (I):

Structure (I) wherein _R is a C3 to _C27 alkyl moiety. In one embodiment, R is a _C11 to _C25 , or a _C15 to _C23 alkyl moiety. In another embodiment, R is a _C21 alkyl moiety. R can be saturated, monounsaturated or polyunsaturated. In one embodiment, R is monounsaturated. Non-limiting examples of suitable fatty acid amides include erucamide, oleamide, palmitamide, stearylamine, and behenamide. In addition, the fatty acid amide can be a mixture of two or more fatty acid amides. In one embodiment, the fatty acid amide is erucamide.

結構（II） 其中R¹ 及R² 各自獨立地為氫或烴基。「烴基」為藉由自烴（例如烷基，諸如乙基；或芳基，諸如苯基）移除氫原子所形成之單價基團。矽氧烷單體殘基可為具有相同或不同烷基、芳基、烷芳基或芳烷基部分之任何二烷基、二芳基、二烷芳基或二芳烷基矽氧烷。在一個實施例中，R¹ 及R² 中之每一者獨立地為C₁ 至C₂₀ 、或C₁ 至C₁₂ 、或C_{1 至} C₆ 烷基、芳基、烷芳基或芳烷基部分。 R¹ 及R² 可具有相同或不同數目個碳原子。在一個實施例中，對於各R¹ 及R² ，烴基為飽和且視情況直鏈之烷基。對於各R¹ 及R² ，烷基可為相同或可為不同。適用於R¹ 及R² 之烷基之非限制性實例包含甲基、乙基、1-丙基、2-丙基、1-丁基、異丁基、第三丁基或其兩者或超過兩者之組合。適合之聚矽氧之非限制性實例包含聚二甲基矽氧烷（PDMS）、聚(乙基-甲基矽氧烷）及其組合。In one embodiment, the slip agent is polysiloxane. "Polysiloxanes" are polymers that typically include repeating units of siloxane-based monomer residues. A "Siloxane" is a repeating unit of a monomer residue having structure (II):

Structure ( ^{II )} wherein R1 and R2 are each independently hydrogen or hydrocarbyl. A "hydrocarbyl group" is a monovalent group formed by removing a hydrogen atom from a hydrocarbon (eg, an alkyl group such as ethyl; or an aryl group such as phenyl). The siloxane monomer residue can be any dialkyl, diaryl, dialkylaryl or diaralkylsiloxane having the same or different alkyl, aryl, alkaryl or aralkyl moieties. In one embodiment, each of R ¹ and R ² is independently C ₁ to C ₂₀ , or C ₁ to C ₁₂ , or C _{1 to} C ₆ alkyl, aryl, alkaryl, or aralkane base part. R ¹ and R ² may have the same or different numbers of carbon atoms. ^{In one} embodiment, for each R1 and R2, the hydrocarbyl group is a saturated and optionally straight chain alkyl group. The alkyl groups may be the same or may be different for each of R ¹ and R ² . Non-limiting examples of suitable alkyl groups for R1 and R2 include methyl, ethyl, ¹ -propyl, ² -propyl, 1-butyl, isobutyl, tert-butyl, or both or more than a combination of the two. Non-limiting examples of suitable polysiloxanes include polydimethylsiloxane (PDMS), poly(ethyl-methylsiloxane), and combinations thereof.

In one embodiment, the slip agent is selected from the group consisting of fatty acid amides, polysiloxanes, and combinations thereof. In another embodiment, the slip agent is selected from the group consisting of erucamide, oleamide, palmitamide, stearylamine, behenamide, PDMS, and combinations thereof.

In one embodiment, the slip agent does not include polysiloxane. In another embodiment, the slip agent does not include polydimethylsiloxane (PDMS).

In one embodiment, the slip agent is a stearate. Non-limiting examples of suitable stearate salts include zinc stearate, lead stearate, calcium stearate, and combinations thereof.

In one embodiment, the slip agent is sulfate. A non-limiting example of a suitable sulfate is zinc sulfate.

In one embodiment, the slip agent is a fatty acid. Non-limiting examples of suitable fatty acids include palmitic acid, stearic acid, and combinations thereof.

In one embodiment, the slip agent is a fluorinated organic resin. "Fluorinated organic resins" are one or more fluorinated monomers selected from tetrafluoroethylene, vinylidene fluoride and chlorotrifluoroethylene.

In one embodiment, each skin layer contains 2,000 ppm, or 2,500 ppm, or 3,000 ppm, or 3,100 ppm, or 3,200 ppm to 3,300 ppm, or 3,400 ppm, or 3,500 ppm of slip agent.

In one embodiment, each skin layer contains 0.20 wt%, or 0.25 wt%, or 0.30 wt%, or 0.31 wt%, or 0.32 wt% to 0.33 wt%, or 0.34 wt%, or 0.34 wt%, based on the total weight of each skin layer. 0.35 wt% slip agent.

The slip agent can include two or more of the embodiments disclosed herein. iii. Anti-caking agent

Each surface layer contains an anti-caking agent. An "anti-caking agent" is a compound that causes caking between two adjacent layers of a film by creating a microscopic roughening of the surface of the film layer that reduces the contact area available between adjacent layers (ie sticking) to a minimum.

Non-limiting examples of suitable anti-caking agents include silica, talc, calcium carbonate, and combinations thereof. In one embodiment, the anti-caking agent is silicon dioxide (SiO _{2 ).} The silica can be organic silica or synthetic silica.

In one embodiment, each surface layer contains 4,000 ppm, or 4,500 ppm, or 5,000 ppm, or 5,500 ppm, or 6,000 ppm to 6,500 ppm, or 7,000 ppm, or 7,500 ppm, or 8,000 ppm, or 8,500 ppm, or 9,000 ppm , or 9,500 ppm, or 10,000 ppm of anti-caking agent.

In one embodiment, each skin layer contains 0.40 wt %, or 0.45 wt %, or 0.50 wt %, or 0.55 wt %, or 0.60 wt % to 0.65 wt %, or 0.70 wt %, based on the total weight of each corresponding skin layer , or 0.75 wt%, or 0.80 wt%, or 0.85 wt%, or 0.90 wt%, or 0.95 wt%, or 1.00 wt% of an anti-caking agent.

The anti-caking agent can include two or more of the embodiments disclosed herein. iv. Additives as appropriate

In one embodiment, each skin layer contains optional additives. The optional additive can be any of the additives disclosed herein. In one embodiment, each skin layer contains an additive selected from the group consisting of antioxidants, antistatic agents, stabilizers, nucleating agents, colorants, ultraviolet (UV) absorbers or stabilizers, flame retardants, compatibilizers agents, plasticizers, fillers, processing aids, cross-linking agents such as peroxides, and combinations thereof.

In one embodiment, each skin layer contains 0 wt %, or 0.01 wt %, or 0.05 wt %, or 0.1 wt %, or 0.2 wt % to 0.3 wt %, or 0.4 wt %, based on the total weight of each skin layer, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive.

The propylene homopolymer can be the only polymeric component in each skin layer, or the propylene homopolymer can be present with one or more polymeric components in combination with the propylene homopolymer. Non-limiting examples of suitable polymeric components are polyolefins, such as ethylene-based polymers or propylene-based polymers. The optional polyolefin is different from the propylene homopolymer. It should be understood, however, that each skin layer may comprise a blend of two or more different propylene homopolymers. In one embodiment, each skin layer does not include an optional polyolefin. In another embodiment, each skin layer does not include an ethylene-based polymer. In one embodiment, each skin layer comprises 15 wt %, or 16 wt % to 18 wt %, or 20 wt %, or 22 wt %, or 25 wt %, or 30 wt % ethylene, based on the total weight of each skin layer polymer.

In one embodiment, each skin layer contains: (i) 70 wt%, or 75 wt%, or 77 wt% to 80 wt%, or 83 wt%, or 85 wt%, or 90 wt%, or 95 wt% , or 96 wt%, or 97 wt%, 98 wt%, or 99 wt%, or 99.3 wt%, 99.4 wt% of a propylene homopolymer having one, some or all of the following properties: (a ) MFR of 2.0 g/10 min, or 3.0 g/10 min, or 4.0 g/10 min to 5.0 g/10 min, or 6.0 g/10 min, or 7.0 g/10 min, or 8.0 g/10 min, or 9.0 g/10 min, or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min; and/or (b) a density of 0.900 g/cc, or 0.902 g/cc, 0.903 g/cc, or 0.904 g/cc to 0.906 g/cc, or 0.908 g/cc; and/or (c) a melting temperature Tm of 155°C, or 157°C, or 159°C to 161°C, or 163°C, or 165°C; (ii) 2,000 ppm, or 2,500 ppm, or 3,000 ppm, or 3,100 ppm, or 3,200 ppm to 3,300 ppm, or 3,400 ppm, or 3,500 ppm of slip agents, such as fatty acid amides (e.g. erucamide); (iii) 4,000 ppm, or 4,500 ppm, or 5,000 ppm, or 5,500 ppm, or 6,000 ppm to 6,500 ppm, or 7,000 ppm, or 7,500 ppm, or 8,000 ppm, or 8,500 ppm, or 9,000 ppm , or 9,500 ppm, or 10,000 ppm of an anti-caking agent, such as silica; (iv) 0 wt%, or 0.01 wt%, or 0.05 wt%, or 0.1 wt%, or 0.2 wt% to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive; and (v) 0 wt%, or 15 wt%, or 16 wt% to 18 wt%, or 20 wt%, or 22 wt%, or 25 wt%, or 30 wt% of vinyl polymers; and the thickness of each surface layer is 0.75 µm, or 1.0 µm, or 1.5 µm, or 2.0 µm, or 3.0 µm, or 4.0 µm, or 5.0 µm, or 6.0 µm, or 6.5 µm to 7. 0 µm, or 7.5 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 20.0 µm, or 25.0 µm, or 30 µm .

In one embodiment, each skin layer contains: (i) 70 wt%, or 75 wt%, or 77 wt% to 80 wt%, or 83 wt%, or 85 wt%, or 90 wt%, or 95 wt% , or 96 wt%, or 97 wt%, 98 wt%, or 99 wt%, or 99.3 wt%, 99.4 wt% of a propylene homopolymer having one, some or all of the following properties: (a ) MFR of 2.0 g/10 min, or 3.0 g/10 min, or 4.0 g/10 min to 5.0 g/10 min, or 6.0 g/10 min, or 7.0 g/10 min, or 8.0 g/10 min, or 9.0 g/10 min, or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min; and/or (b) a density of 0.900 g/cc, or 0.902 g/cc, 0.903 g/cc, or 0.904 g/cc to 0.906 g/cc, or 0.908 g/cc; and/or (c) a melting temperature Tm of 155°C, or 157°C, or 159°C to 161°C, or 163°C, or 165°C; (ii) 0.20 wt%, or 0.25 wt%, or 0.30 wt%, or 0.31 wt%, or 0.32 wt% to 0.33 wt%, or 0.34 wt%, or 0.35 wt% slip aid (iii) 0.40 wt%, or 0.45 wt%, or 0.50 wt%, or 0.55 wt%, or 0.60 to 0.65 wt%, or 0.70 wt%, or 0.75 wt%, or 0.80 wt%, or 0.85 wt%, or 0.90 wt%, or 0.95 wt%, or 1.00 wt% an anti-caking agent, such as silica; (iv) 0 wt%, or 0.01 wt% , or 0.05 wt%, or 0.1 wt%, or 0.2 to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive; and (v) 0 wt %, or 15 wt %, or 16 wt % to 18 wt %, or 20 wt %, or 22 wt %, or 25 wt %, or 30 wt %, based on the total weight of each skin layer, ethylene-based polymer; and The thickness of each surface layer is 0.75 µm, or 1.0 µm, or 1.5 µm, or 2.0 µm, or 3.0 µm, or 4.0 µm, or 5.0 µm, or 6.0 µm, or 6.5 µm to 7.0 µm, or 7.5 µm, or 8.0 µm ,or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 20.0 µm, or 25.0 µm, or 30 µm.

It is understood that the sum of the components in each skin layer disclosed herein (including the foregoing layers) results in 100 weight percent (wt%) based on the total weight of the corresponding skin layer.

The skin layers may have the same or different compositions. In one embodiment, each skin layer has the same composition.

Each skin layer has two opposing surfaces. In one embodiment, each skin layer is a continuous layer having two opposing surfaces.

The skin layer may include two or more than two embodiments disclosed herein. C. Multilayer film

The multilayer film contains at least three layers, comprising (A) a core layer comprising high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc, and optional additives; and (B) relative to the core layer surface layer on the side. Each skin layer contains (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; (iii) 4,000 to 10,000 ppm of anti-caking agent; and (iv) additives as appropriate. The core and skin layers can be any of the core and skin layers disclosed herein.

Multilayer films contain three or more layers. For example, a multilayer film may have three, four, five, six, seven, eight, nine, ten, eleven, or more than eleven layers. In one embodiment, the multilayer film contains only three layers.

In one embodiment, the multilayer film consists essentially of or consists of at least three layers comprising (A) HDPE with a core layer having a density of 0.940 g/cc to 0.980 g/cc, and optional additives; and (B) Skin layers on opposite sides of the core layer. Each skin layer contains (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; (iii) 4,000 to 10,000 ppm of anti-caking agent; and (iv) additives as appropriate.

The skin layer may be in direct or indirect contact with the core layer. In one embodiment, the skin layer directly contacts the core layer. As used herein, the term "direct contact" is where the core layer is immediately adjacent to each skin layer and there are no intervening layers or intervening structures between the core layer and each skin layer. In another embodiment, the skin layer indirectly contacts the core layer. As used herein, the term "indirect contact" is a layer configuration in which an intervening layer or intervening structure exists between the core layer and each skin layer.

In one embodiment, the thickness of the multilayer film is 15 µm, or 20 µm, or 25 µm, or 30 µm, or 33 µm to 37 µm, or 40 µm, or 45 µm, or 50 µm, or 55 µm, or 60 µm, or 65 µm, or 70 µm, or 75 µm, or 80 µm, or 85 µm, or 90 µm, or 95 µm, or 100 µm.

In one embodiment, the core layer is 40 vol%, or 45 vol%, or 50 vol%, or 55 to 60 vol%, or 65 vol%, or 70 vol%, or 65 vol%, or 70 vol%, of the total volume of the multilayer film, or 75 vol% , or 80 vol%, or 85 vol%, or 90 vol%.

In one embodiment, the combined volume of the skin layers is 10 vol%, or 15 vol%, or 20 vol%, or 25 vol%, or 30 vol%, or 35 vol%, or 40 vol% of the total volume of the multilayer film to 45 vol%, or 50 vol%, or 55 vol%, or 60 vol%. In one embodiment, the volume of each individual skin layer is 5 vol%, or 7.5 vol%, or 10 vol%, or 12.5 vol%, or 15 vol%, or 20 vol% to 22.5 vol% of the total volume of the multilayer film , or 25 vol%, or 27.5 vol%, or 30 vol%.

In one embodiment, the thickness of the core layer is 6.0 µm, or 7.0 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 16.0 µm, or 17.0 µm, or 18.0 µm, or 19.0 µm, or 19.8 µm to 22.2 µm, or 23.0 µm, or 25 µm, or 30 µm, or 35 µm, or 40 µm, or 45 µm, or 50 µm , or 65 µm, or 70 µm, or 75 µm, or 80 µm, or 85 µm, or 90 µm; and the thickness of each surface layer is 0.75 µm, or 1.0 µm, or 1.5 µm, or 2.0 µm, or 3.0 µm, or 4.0 µm, or 5.0 µm, or 6.0 µm, or 6.5 µm to 7.0 µm, or 7.5 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm , or 15.0 µm, or 20.0 µm, or 25.0 µm, or 30 µm.

等式（I） 在等式（I）中，各對應的層之重量%（「wt%」）係以膜之總重量計。In one embodiment, the slip factor of the multilayer film is 25,000, or 26,000, or 30,000, or 35,000, or 39,000 to 40,000, or 45,000, or 49,000, or 50,000, or 52,000, or 55,000, or 60,000. The "slip factor" of the multilayer film is calculated according to the following equation (I):

Equation (I) In Equation (I), the weight % ("wt%") of each corresponding layer is based on the total weight of the film.

In one embodiment, the multi-layer film has a coefficient of friction (COF) of 0.05, or 0.10, or 0.15, or 0.19, or 0.20, or 0.24 to 0.25, or 0.26, or 0.27, or 0.28, or 0.29, or 0.30, or 0.31, or 0.32, or 0.33, or 0.34, or 0.35, or 0.36, or 0.37, or 0.38.

In one embodiment, the twist retention of the multilayer film after 7 days of aging is 66%, or 70% to 75%, or 80%, or 85%, or 90%, or 95%, or 100%. The higher twist retention (≥66%) after 7 days of aging indicates that the multilayer film retains the folded/twisted form after aging. Therefore, the multilayer films of the present invention are suitable for twist packaging.

In one embodiment, the multilayer film has a yield tension of 5 MPa, or 8 MPa, or 10 MPa, or 13 MPa to 14 MPa, or 15 MPa, or 15.5 MPa, or less than 16 MPa. During folding and/or twisting of the multilayer film, tension is applied to the multilayer film and the film stretches, and when the tension is removed the film returns to its original dimensions until the applied tension is the "yield tension", at which point the multilayer film stretches but The deformation is permanent (indicating that the multilayer film retains its folded/twisted form). A low yield tension of 5 MPa to 15.5 MPa, or less than 16 MPa, is advantageous because it enables the multilayer film to be permanently deformed and held by the lower tension applied to the multilayer film by folding/twisting.

In one embodiment, the multilayer film has at least three layers comprising: (A) a core layer comprising 80 wt %, or 85 wt %, or 90 wt %, or 95 wt % to 97 wt%, or 98 wt%, or 99 wt%, or 100 wt% HDPE, and 0 wt%, or 0.01 wt%, or 0.05 wt%, or 0.1 wt%, or 0.2 wt% to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive, the HDPE having one, some or all of the following properties: (i) a density of 0.940 g/cc, or 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc, or 0.958 g/cc to 0.960 g/cc, or 0.962 g/cc, or 0.965 g/cc, or 0.970 g/cc, or 0.975 g/ cc, or 0.980 g/cc; and/or (i) a melt index (MI) of 0.1 g/10 min, or 0.5 g/10 min to 1.0 g/10 min, or 1.5 g/10 min, or 2.0 g/ 10 min; and/or (iii) greater than 50 wt%, or 55 wt%, or 60 wt%, or 65 wt% to 70 wt%, or 75 wt%, or 80 wt%, or 75 wt%, or 80 wt%, based on the total weight of HDPE, or 85 wt%, or 90 wt%, or 95 wt%, or 97 wt%, or 99 wt%, or 100 wt% of units derived from ethylene, and inverse amounts, or 0 wt%, or 1 wt%, or 3 wt%, or 5 wt%, or 10 wt%, or 15 wt%, or 20 wt%, or 25 wt%, or 30 wt% to 35 wt%, or 40 wt%, or 45 wt%, or less than 50 wt % of units derived from comonomers; (B) skin layers on opposite sides of the core layer, each skin layer comprising: (i) 70 wt %, or 75 wt %, or 77 wt % to 80 wt % , or 83 wt%, or 85 wt%, or 90 wt%, or 95 wt%, or 96 wt%, or 97 wt%, 98 wt%, or 99 wt%, or 99.3 wt%, 99.4 wt% propylene a propylene homopolymer having one, some or all of the following properties: (a) an MFR of 2.0 g/10 min, or 3.0 g/10 min, or 4.0 g/10 min to 5.0 g/10 min, or 6.0 g/10 min, or 7.0 g/10 min, or 8.0 g/10 min, or 9.0 g/10 min, or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min; and/or (b) a density of 0.900 g/cc, or 0.902 g/cc, 0.903 g/cc, or 0.904 g /cc to 0.906 g/cc, or 0.908 g/cc; and/or (c) a melting temperature Tm of 155°C, or 157°C, or 159°C to 161°C, or 163°C, or 165°C; (ii) 0.20 wt %, or 0.25 wt %, or 0.30 wt %, or 0.31 wt %, or 0.32 wt % to 0.33 wt %, or 0.34 wt %, or 0.35 wt % slip agents, such as fatty acid amides (eg, erucamides) ); (iii) 0.40 wt%, or 0.45 wt%, or 0.50 wt%, or 0.55 wt%, or 0.60 to 0.65 wt%, or 0.70 wt%, or 0.75 wt%, or 0.80 wt%, or 0.85 wt%, or 0.90 wt%, or 0.95 wt%, or 1.00 wt% of an anti-caking agent, such as silica; (iv) 0 wt%, or 0.01 wt%, or 0.05 wt%, or 0.1 wt%, or 0.2 to 0.3 wt%, or 0.4 wt%, or 0.5 wt%, or 1.0 wt%, or 2.0 wt%, or 3.0 wt% additive; and (v) 0 wt% based on the total weight of each skin layer, or 15 wt%, or 16 wt% to 18 wt%, or 20 wt%, or 22 wt%, or 25 wt%, or 30 wt% ethylene-based polymer; and the multilayer film has one, some or all of the following properties : (1) Total thickness of 15 µm, or 20 µm, or 25 µm, or 30 µm, or 33 µm to 37 µm, or 40 µm, or 45 µm, or 50 µm, or 55 µm, or 60 µm, or 65 µm, or 70 µm, or 75 µm, or 80 µm, or 85 µm, or 90 µm, or 95 µm, or 100 µm; and/or (2) the core layer is 40 vol% of the total volume of the multilayer film, or 45 vol%, or 50 vol%, or 55 vol% to 60 vol%, or 65 vol%, or 70 vol%, or 75 vol%, or 80 vol%, or 85 vol%, or 90 vol%; and or (3) the thickness of the core layer is 6.0 µm, or 7.0 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 16.0 µm, or 17.0 µm, or 18.0 µm, or 19.0 µm, or 19.8 µm to 22.2 µm, or 23.0 µm, or 25 µm, or 30 µm, or 35 µm, or 40 µm, or 45 µm, or 50 µm, or 65 µm, or 70 µm, or 75 µm, or 80 µm, or 85 µm, or 90 µm; and/or (4) the combined volume of the surface layer is 10 vol%, or 15 vol%, or 20 vol%, of the total volume of the multilayer film, or 25 vol%, or 30 vol%, or 35 vol%, or 40 vol% to 45 vol%, or 50 vol%, or 55 vol%, or 60 vol%; and/or. (5) The thickness of each surface layer is 0.75 µm, or 1.0 µm, or 1.5 µm, or 2.0 µm, or 3.0 µm, or 4.0 µm, or 5.0 µm, or 6.0 µm, or 6.5 µm to 7.0 µm, or 7.5 µm, or 8.0 µm, or 9.0 µm, or 10.0 µm, or 11.0 µm, or 12.0 µm, or 13.0 µm, or 14.0 µm, or 15.0 µm, or 20.0 µm, or 25.0 µm, or 30 µm; and/or (6) A slip factor of 25,000, or 26,000, or 30,000, or 35,000, or 39,000 to 40,000, or 45,000, or 49,000, or 50,000, or 52,000, or 55,000, or 60,000; and/or (7) a coefficient of friction (COF) of 0.05 , or 0.10, or 0.15, or 0.19, or 0.20, or 0.24 to 0.25, or 0.26, or 0.27, or 0.28, or 0.29, or 0.30, or 0.31, or 0.32, or 0.33, or 0.34, or 0.35, or 0.36 , or 0.37, or 0.38; and/or (8) Torsion remains 66%, or 70% to 75%, or 80%, or 85%, or 90%, or 95%, or 100% after aging for 7 days and/or (9) a yield tension of 5 MPa, or 8 MPa, or 10 MPa, or 13 MPa to 14 MPa, or 15 MPa, or 15.5 MPa.

In one embodiment, the multilayer film has at least 2, or at least 3, or at least 4, or at least 5, or at least 6, or at least 7, or at least 8 of properties (1) to (9). species, or all 9 species.

It is understood that the sum of the components in each of the layers disclosed herein (including the foregoing layers) results in 100 weight percent (wt %) based on the total weight of the corresponding layer.

In one embodiment, the multilayer film is a coextruded film produced via a casting process. Multilayer films produced by casting processes do not include multi-layer films produced by blowing processes. Without wishing to be bound by any particular theory, Applicants believe that the casting process results in a higher stiffness of the multilayer film, which results in improved (ie, higher) torsional retention.

In one embodiment, the multilayer film is not an oriented film. In another embodiment, the multilayer film is not bidirectionally oriented. In other words, the multilayer film is not stretched after extrusion.

In one embodiment, the multilayer film is coextruded and unlaminated.

Multilayer films may include two or more of the embodiments disclosed herein. D. Products

The present invention also provides articles comprising the multilayer films. The multilayer film can be any of the multilayer films disclosed herein.

In one embodiment, the article comprises a candy and a multilayer film in contact with the candy. In one embodiment, the multilayer film contains at least three layers, comprising (A) a core layer comprising high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc and optional additives; and in the core The skin layer on the opposite side of the layer. Each skin layer contains (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of slip agent; (iii) 4,000 to 10,000 ppm of anti-caking agent; and (iv) additives as appropriate.

The article of manufacture contains candy. Non-limiting examples of suitable confections include sugar confections, chocolate confections, and combinations thereof. Non-limiting examples of candy confections include lollipops, hard candies, fondant, licorice, caramel, chewing gum, nut candy, candied fruit, caramel, toffee, marzipan, toffee, halva, cotton Gummies, mints, and combinations thereof. Non-limiting examples of chocolate confections include fudge, chocolate bars, chocolate bars, chocolate-covered nuts, chocolate-covered fruit, chocolate mints, and truffles.

The multilayer film may be in direct or indirect contact with the confectionery. In one embodiment, the multilayer film is in direct contact with the candy.

The multilayer film can be twisted and/or folded around the candy. In one embodiment, the multilayer film is folded and then twisted at opposite ends of the candy.

An article of manufacture may include two or more of the embodiments disclosed herein.

By way of example and not limitation, some embodiments of the invention will now be described in detail in the following examples. example

The materials used in the examples are provided in Table 1A below. Table 1A

Multilayer film samples were fabricated on a Collins casting line with the conditions provided in Table IB. Table 1B. Cast Film Fabrication Conditions

The layer configurations and multilayer film structures are provided in Table 2 below. Each multilayer film structure is formed from a core layer (A), which is 60% by volume of the multilayer film, and two skin layers (B1 and B2). The volume of each skin layer (B1 and B2) was 20% by volume of the multilayer film. In other words, the combined skin layers (B1 and B2) accounted for 40% by volume of the multilayer film. In Table 2, the amounts of slip and anti-caking agents refer to the corresponding amounts of slip and anti-caking agents contained in the layers (not the slip masterbatch and/or anti-caking agents contained in the layers). amount of the masterbatch). In Table 2, the contents of each layer are listed in weight percent (wt%) and/or ppm (parts per million) based on the total weight of the corresponding layer. For example, the skin layer (B1) of Example 3 contained 78.5 wt% CUYOLEN™ 1102L based on the total weight of the skin layer (B1); 3,500 ppm slip agent (i.e. 0.35 wt% slip agent); 8,000 ppm anti-caking agent ( i.e. 0.8 wt% anti-caking agent); and 20.35 wt% masterbatch polyethylene carrier (“MB PE”) (i.e. (i) 17.15 wt% polyethylene carrier from the anti-slip agent masterbatch and (ii) ) combined content of 3.2 wt% polyethylene carrier from the anti-caking agent masterbatch).

⁺ 對於CS 2未量測摩擦係數（COF），因為其展現不良扭轉保持（亦即≤50%扭轉保持）表明多層膜不適用於扭轉包裝。 CS = 比較樣品 NM = 未量測 MB PE= 母料聚乙烯載劑之總量Multilayer film samples were tested for COF, torsional retention and yield tension. The results are provided in Table 2 below. Table 2

⁺ The coefficient of friction (COF) was not measured for CS 2 as it exhibited poor torsional retention (ie ≤50% torsional retention) indicating that the multilayer film is not suitable for torsional packaging. CS = Comparative sample NM = Not measured MB PE = Total amount of masterbatch polyethylene carrier

A comparative sample film comprising three layers: comprising (A) a core layer comprising HDPE having a density of 0.940-0.980 g/cc; and (B) a skin layer on the opposite side of the core layer, the skin layer comprising (i) propylene/ Ethylene copolymer and no propylene homopolymer; (ii) no slip agent; and (iii) no anti-caking agent (CS 3 - 5), exhibiting high COF (>0.38), indicating that multilayer films are not suitable for twist packaging , because the mechanical processing of the multilayer film is prevented when the COF of the multilayer film is greater than 0.38.

Applicants have unexpectedly discovered a multilayer film comprising three layers: comprising (A) a core layer comprising HDPE having a density of 0.940-0.980 g/cc; and (B) skin layers on opposite sides of the core layer, each skin layer comprising ( i) propylene homopolymer; (ii) 2,000-3,500 ppm slip agent; and (iii) 4,000-10,000 ppm anti-caking agent (Example 1, Example 2, Example 3), advantageously exhibiting a unique balance of: high Torsion retention (66%-100%) to maintain the clad form, low COF (0.05-0.38) to improve the machining of the multilayer film, and low yield tension (≤15.5 MPa) to enable the multilayer film to be permanently deformed by The lower tension fold/twist retention applied to the multilayer film indicates that the multilayer film is suitable for twist packaging.

It is specifically intended that the present invention is not limited to the embodiments and illustrations contained herein, but includes modifications of those embodiments, including parts of the embodiments that appear within the scope of the claims below, and A combination of elements of different embodiments.

none

1 is a perspective view of a twist-coated confectionery according to an embodiment of the present invention.

Figure 2 is a perspective view of an uncoated candy. definition

Any reference to the Periodic Table of the Elements is the Periodic Table of the Elements as published by CRC Press, Inc., 1990-1991. Element groups referenced in this table are new symbols for numbered groups.

For the purposes of U.S. patent practice, the contents of any referenced patent, patent application, or publication are incorporated by reference in their entirety (or the equivalent U.S. version thereof is so incorporated by reference), especially herein. Definitions in the art (to the extent inconsistent with any definitions specifically provided in this disclosure) and disclosure aspects of common knowledge.

Numerical ranges disclosed herein include all values from and including lower and higher values. For ranges containing exact values (eg 1 or 2, or 3 to 5, or 6 or 7), any sub-range between any two exact values is inclusive (eg 1 to 2; 2 to 6; 5 to 7) ; 3 to 7; 5 to 6, etc.).

Unless stated to the contrary, implied from the context, or customary in the art, all parts and percentages are by weight and all test methods are current as of the filing date of this disclosure.

The term "composition" refers to a mixture of materials comprising the composition as well as reaction products and decomposition products formed from the materials of the composition.

As used herein, the term "blend" or "polymer blend" is a blend of two or more polymers. Such blends may or may not be miscible (not separated at the molecular level). The blend may or may not be phase separated. Such blends may or may not contain one or more domain configurations, as determined from transmission electron spectroscopy, light scattering, x-ray scattering, and other methods known in the art.

The terms "comprising", "comprising", "having" and derivatives thereof are not intended to exclude the presence of any additional components, steps or procedures, whether or not specifically disclosed. For the avoidance of any doubt, unless stated to the contrary, all compositions claimed through the use of the term "comprising" may contain any additional additives, adjuvants or compounds, whether polymeric or otherwise. In contrast, the term "consisting essentially of" excludes from the scope of any subsequent enumeration any other components, steps or procedures, except those not necessary for operability. The term "consisting of" excludes any component, step or procedure not specifically recited or listed. Unless stated otherwise, the term "or" refers to the recited members individually and in any combination. The use of the singular includes the use of the plural, and vice versa.

"Ethylene-based polymers" are polymers containing more than 50 weight percent polymerized vinyl monomers (based on the total amount of polymerizable monomers) and optionally at least one comonomer. Ethylene-based polymers include ethylene homopolymers and ethylene copolymers (having units derived from ethylene and one or more comonomers). The terms "ethylene polymer" and "polyethylene" are used interchangeably. A non-limiting example of an ethylene-based polymer (polyethylene) is high density polyethylene (HDPE).

An "olefin-based polymer" or "polyolefin" is a polymer that contains (based on the total amount of polymerizable monomers) more than 50% by weight of polymerized olefin monomers and optionally at least one comonomer. Non-limiting examples of olefin-based polymers include ethylene-based polymers and propylene-based polymers.

A "polymer" is a compound prepared by polymerizing monomers (whether of the same or different types) that provide in polymerized form the multiple and/or repeating "units" or "mer units" that make up the polymer . Thus, the generic term polymer encompasses the term homopolymer, which is generally used to refer to polymers prepared from only one type of monomer; and the term interpolymer, which is generally used to refer to polymers prepared from at least two types of monomers. A polymer prepared from a type of monomer. It also encompasses all forms of copolymers such as random, block and the like. The terms "ethylene/alpha-olefin polymer" and "propylene/alpha-olefin polymer" refer to copolymers as described above, prepared by the polymerization of ethylene or propylene, respectively, and one or more other polymerizable alpha-olefin monomers. It should be noted that although polymers are often referred to as being "made from" one or more specific monomers, "based on" a specific monomer or monomer type, "containing" a specific monomer content, or the like, in this case Hereinafter, the term "monomer" should be understood to refer to the polymerized residue of a specific monomer, and not to refer to unpolymerized species. In general, polymers herein refer to "units" based on the polymerized form of the corresponding monomers.

The term "propylene-based polymer" is a polymer containing (based on the total amount of polymerizable monomers) more than 50% by weight of polymerized propylene monomer and optionally at least one comonomer. Propylene-based polymers include propylene homopolymers (having units derived from propylene and no comonomers), and propylene copolymers (having units derived from propylene and one or more comonomers). The terms "propylene polymer" and "polypropylene" are used interchangeably. A propylene-based polymer, a non-limiting example of polypropylene, is a propylene/α-olefin copolymer with at least one _C2 or _C4 - _C10 α-olefin comonomer, or a C2 α _- olefin comonomer. testing method

Coefficient of friction (COF) is measured according to ASTM D1894. The matrix used for the COF determination was DOW HDPE DGDB-2480 NT, a high density polyethylene commercially available from The Dow Chemical Company, Midland, MI, USA.

Density is measured according to ASTM D792, Method B. Results are recorded in Pa·s.

The melt index (MI) (I2) of vinyl polymers is measured in g/10 min using ASTM D-1238-04 (190°C/2.16 kg).

The melt flow rate (MFR) of propylene-based polymers is measured in g/10 min using ASTM D-1238-04 (230°C/2.16 kg).

Torsion remains determined by the following procedure after aging for 7 days. Cut the membrane into 80 mm × 80 mm samples. Personnel then folded the film sample around a piece of Arcor ^™ Butter Toffee (hard candy). Personnel then twisted the opposite ends of the film tightly around the hard candy piece, similar to a single twist-coated hard candy as shown in Figure 1. Each film sample was cut in the same direction of extrusion and the twisting procedure was performed by the same individual to minimize sample-to-sample variation. Five or six coated candies were made. Each coated candy was stored at ambient conditions (23°C, 760 mmHg, 50% relative humidity) and visually observed daily over a 7 day period to determine if the multilayer film maintained its fold/twist or if the film unfolded. Uncoated hard candies are those in which the fold/twist is not maintained so that the film moves from its original twist-coated hard candy form, as shown in FIG. 2 . The number of samples that remained folded/twisted was recorded daily. Torsion retention after 7 days of aging is reported as the percentage of samples that retained their folds/torsion after 7 days.

Yield tension is measured according to ASTM D882. Yield tension is measured in the longitudinal direction of the film. Differential Scanning Calorimetry (DSC)

Differential Scanning Calorimetry (DSC) can be used to measure the melting, crystallization and glass transfer behavior of polymers over a wide range of temperatures. For example, a TA Instruments Q1000 DSC equipped with an RCS (refrigerated cooling system) and an autosampler was used to perform this analysis. During the test, the gas flow was flushed with nitrogen at 50 ml/min. Each sample was melt pressed into a film at 190°C; the molten sample was then air cooled to room temperature (25°C). 3-10 mg, 6 mm diameter samples were extracted from the cooled polymer, weighed, placed in lightweight aluminum pans (50 mg), and crimped closed. Analysis was then performed to determine its thermal properties.

The thermal behavior of the sample is determined by slowly raising and lowering the temperature of the sample to establish a heat flow relative to a temperature profile. First, the sample was rapidly heated to 180°C and held isothermal for 3 minutes in order to remove its thermal history. Next, the sample was cooled to -80°C at a cooling rate of 10°C/min and kept isothermal at -80°C for 3 minutes. The sample was then heated to 180°C at a heating rate of 10°C/min (this is the "second heat" ramp). The cooling and second heating curves were recorded. The values determined are the extrapolated melting onset Tm and the extrapolated crystallization onset Tc. For polyethylene samples, heat of fusion (Hf) (in Joules per gram), % crystallinity was calculated using the following equation: % crystallinity = ((Hf)/292 J/g) × 100; and for polyethylene The % crystallinity calculated for the propylene samples used the following equation: % crystallinity = ((Hf)/165 J/g) x 100.

Heat of fusion (Hf) and peak melting temperature are reported from the second heating curve. The peak crystallization temperature was determined from the cooling curve.

The melting point _Tm was determined from the DSC heating curve by first drawing a baseline between the start and end of the melt transfer. A tangent to the data on the low temperature side of the melting peak is then drawn. Where this line intersects the baseline is the extrapolated melting onset ( _Tm ). This is as in Bernhard Wunderlich, The Basis of Thermal Analysis, in Thermal Characterization of Polymeric Materials 92, 277-278 (Edith A. Turi ed., 2nd ed. 1997) Described. ¹³ C NMR experimental procedure for propylene polymers

¹³ C NMR was used for ethylene content and performed as follows:

Sample Preparation ( Propylene-Based Polymers ) - Samples were prepared by adding approximately 2.7 g of tetrachloroethane- _d2 /50/ of o-dichlorobenzene containing 0.025 M Cr(AcAc) ₃ in a Norell 1001-7 10 mm NMR tube 50 mixtures were added to 0.20-0.30 g samples to prepare. The sample was then dissolved and homogenized by heating the tube and its contents to 150°C using a heat block and a heat gun. Each sample was visually inspected to ensure uniformity.

Data Acquisition Parameters ( Propylene-Based Polymers) —Data were collected using a Bruker 400 MHz spectrometer equipped with a Bruker dual DUL high temperature CryoProbe. Data were decoupled using 320 transients per data file, 6 second pulse repetition receive delay, 90 degree dump angle, and reverse gating with a sample temperature of 120°C. All measurements were made on unrotated samples in locked mode. The samples were thermally equilibrated for 7 minutes before data acquisition. % mm stereoisomerism and wt % ethylene are then determined according to methods commonly used in the art. **Reference: For compositions (wt% E): S. Di Martino and M. Kelchtermans; J. Appl. Polym. Sci., Vol. 56, 1781-1787 (1995); Stereoisomerism, detailed assignment: V. Busico, R. Cipullo; Prog. Polym. Sci. Vol. 26, 443-533 (2001).

Claims (14)

A multilayer film comprising at least three layers, the layers comprising: (A) a core layer comprising high density polyethylene (HDPE) having a density of 0.940 g/cc to 0.980 g/cc; (B) in the core layer skin layers on opposite sides, each skin layer comprising: (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm of a slip agent; and (iii) 4,000 to 10,000 ppm of an anti-blocking agent; wherein the friction of the multilayer film The coefficient (COF) is 0.05 to 0.38. The multilayer film of claim 1, wherein the multilayer film has a thickness of 15 μm to 100 μm. The multilayer film as described in item 1 or item 2 of the claimed scope, wherein 40 vol % to 90 vol % of the multilayer film is the core layer, and the combined volume of the skin layers is 10 vol % to 90 vol % of the multilayer film 60 vol%, the multi-layer film maintained torsion of 66% to 100% and yield tension of 5 MPa to 15.5 MPa after 7 days. The multi-layer film according to claim 1 or claim 2, wherein the multi-layer film consists of three layers. The multi-layer film according to claim 1 or claim 2, wherein the multi-layer film is a cast film. The multi-layer film according to item 1 or item 2 of the claimed scope, wherein the HDPE has a melt index of 0.1 g/10min to 1 g/10min. The multilayer film of claim 1 or claim 2, wherein the propylene homopolymer has a melt flow rate of 2 g/10min to 15.0 g/10min. The multilayer film of claim 1 or claim 2, wherein the slip agent is selected from the group consisting of fatty acid amides, polysiloxanes, and combinations thereof. The multilayer film of claim 1 or claim 2, wherein the anti-caking agent is selected from the group consisting of silica, talc, calcium carbonate, and combinations thereof. The multilayer film as described in item 1 or item 2 of the claimed scope, wherein 40 vol % to 90 vol % of the multilayer film is the core layer, and the combined volume of the skin layers is 10 vol % to 90 vol % of the multilayer film 60 vol%, the multi-layer film has a twist retention of 66% to 100% and a yield tension of 5MPa to 15.5MPa after 7 days, and each skin layer includes: (i) a melt flow rate of 2g/10min to 15.0g/10min. Propylene homopolymers; (ii) slip agents selected from the group consisting of erucamide, oleamide, palmitamide, stearylamine, behenamide, polydimethyl amide Siloxanes and combinations thereof; and (iii) Silica. An article comprising: a candy; a multilayer film in contact with the candy, the multilayer film comprising at least three layers, the layers comprising: (A) a core layer comprising a density of 0.940 g/cc to 0.980 g/cc high density polyethylene (HDPE); (B) skin layers on opposite sides of the core layer, each skin layer comprising: (i) a propylene homopolymer; (ii) 2,000 to 3,500 ppm slip agent; and (iii) ) 4,000 to 10,000 ppm of an anti-blocking agent; wherein the multi-layer film has a coefficient of friction (COF) of 0.05 to 0.38. The article of claim 11, wherein the multilayer film is combined with the sugar direct contact. The article of claim 11, wherein the multilayer film is twisted around the candy. The article of any one of claims 11 to 13, wherein 40 vol % to 90 vol % of the multilayer film is the core layer, and the combined volume of the skin layers is that of the multilayer film 10 vol% to 60 vol%, the multi-layer film maintained torsion of 66% to 100% and yield tension of 5 MPa to 15.5 MPa after 7 days.

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