Patent Description:
The research and technological developments on synthetic paper have been focused on the production of a film or sheet capable of being printed and written by a number of inks, including the aqueous inks, from virgin plastic resins. The surface proprieties of at least one of the sides of the film are adequate to be printed or written, by means of the variation of components types and concentration, kind of surface treatment, or even by means of application of different surface coatings. The mechanical and optical proprieties are also qualitatively and quantitatively described, where the film rigidity, opacity, and density are taken into account when producing synthetic paper or film for printing, with balanced proprieties.

For example, <CIT> generally describes a biaxially oriented film including a blend of high density polypropylene and isotactic polyethylene, and at least <NUM> percent by weight of an amorphous, glassy, low molecular weight resin (such as pine resins and saturated terpenes) to improve twist retention.

However, production of synthetic paper to meet these needs has left a void in synthetic papers that can be used for package wrapping, such as gift, floral, and food, and other packaging applications, since synthetic paper to date lacks the ability to fold and tear like paper. For example, synthetic papers to date are typically coated to achieve desired moisture resistance and odor resistance. In addition, synthetic paper developed to date has poor dead fold properties, i.e., the material lacks the ability to maintain the desired angle of a fold and not to "spring back. " Moreover, the synthetic papers developed to date are difficult, if not impossible, to tear without being first cut and will distort when stretched.

As such, there remains a need in the art for a synthetic paper used as a food wrap that reduces or eliminates grease stains and prevents the migration of chemicals and waxes into foods. In addition, there is a need in the art for synthetic papers with a tissue paper-like feel that can be used for a variety of applications, maintain folds, and be easily torn in multiple directions with minimal to no distortion.

<CIT> is mentioned which is concerned with a multilayered laminated resin film and laminated material using it. And, <CIT> is mentioned which is concerned with a film comprising a resin and a filler.

Disclosed are methods and compositions related to synthetic paper-like films with the look and feel of tissue paper.

The present invention provides a synthetic paper synthetic paper including one or more layers of a resin film formed from a composition comprising:.

In one embodiment the one or more layers of a resin film include a continuous olefin resin matrix having calcium carbonate (CaCO<NUM>) uniformly dispersed therein, In one embodiment, the particle size of CaCO<NUM> is at least <NUM>. In another embodiment, the synthetic paper has a tissue paper-like texture and appearance. For example, the synthetic paper can be torn without stretching or distorting the paper or cutting the paper to start the tear.

In one embodiment, the polyolefin resin also includes low density polyethylene linear low density polyethylene, or a mixture thereof. In another embodiment, the particulate filler is present in the composition in an amount of <NUM>% to <NUM>% by weight. In yet another embodiment, the particulate filler includes calcium carbonate.

The synthetic paper may include at least two resin layers. In one embodiment, the synthetic paper includes at least three resin layers. In another embodiment, the synthetic paper has a thickness of about <NUM> mils to about <NUM> mils. The composition includes a cyclic olefin copolymer.

In another embodiment, the synthetic paper has an Elmendorf tear strength of about <NUM> mN to about <NUM> mN in a machine direction. In yet another embodiment, the particulate filler is present in the composition in an amount of about <NUM> percent to about <NUM> percent by weight. In still another embodiment, the particulate filler includes calcium carbonate. Moreover, the synthetic paper may include at least two layers. In this aspect, the at least two layers may include a first layer and a second layer, wherein the polyolefin resin in the first layer is different from the polyolefin in the second layer. The cyclic olefin copolymer may be present in an amount of about <NUM> percent to about <NUM> percent by weight of the composition.

Further features and advantages of the invention can be ascertained from the following detailed description that is provided in connection with the drawing(s) described below:.

Before the present compounds, compositions, articles, devices, and/or methods are disclosed and described, it is to be understood that they are not limited to specific synthetic methods unless otherwise specified, or to particular components unless otherwise specified, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

As used in the specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a polymeric resin" includes mixtures of two or more such polymeric resins, and the like.

Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as "about" that particular value in addition to the value itself. For example, if the value "<NUM>" is disclosed the "less than or equal to <NUM>"as well as "greater than or equal to <NUM>" is also disclosed.

In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings:
"Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

The synthetic paper of the present invention includes one or more layers of a resin film. The one or more layers of a resin film used to form the synthetic paper are formed from a composition that includes a polymeric resin, a low aspect ratio filler, and a tear additive. Other additives, discussed in more detail below may also be included in any of the compositions outlined above. Each component of the compositions used to form the resin film that ultimately becomes the synthetic paper of the present invention is discussed in more detail below. These and other materials are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed that while specific reference of each various individual and collective combinations and permutation of these compounds may not be explicitly disclosed, each is specifically contemplated and described herein. For example, if a particular embodiment of the synthetic paper of the present invention is disclosed and discussed and a number of modifications that can be made are discussed, it is specifically contemplated that each and every combination and permutation of synthetic paper and the modifications that are possible unless specifically indicated to the contrary. Thus, if components A, B, and C are disclosed as well as components D, E, and F, and an example of a composition including A-D is discussed, then even if each is not individually recited, each is individually and collectively contemplated, e.g., compositions including A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are considered disclosed. Likewise, any subset or combination of these is also disclosed. Thus, for example, the sub-group of A-E, B-F, and C-E would be considered disclosed. This concept applies to all aspects of this application including, but not limited to, steps in methods of making and using the disclosed compositions. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific embodiment or combination of embodiments of the disclosed methods.

A synthetic paper of the present invention includes one or more layers of a resin film formed from a composition that comprises a high density polyethylene resin present in an amount of <NUM> percent to <NUM> percent by weight of the composition.

Also disclosed is a polyolefin that may include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE), medium density polyethylene (MDPE), very low density polyethylene (VLDPE), high molecular weight polyethylene (HMWPE), ultra high molecular weight polyethylene (UHMWPE), ultra low molecular weight polyethylene (ULMWPE or PE-WAX), cross-linked polyethylene (PEX or XLPE), high density cross-linked polyethylene (HDXLPE), and combinations thereof. The term polyethylene means ethylene homopolymers or copolymers made of ethylene and at least one other olefin monomer. In addition, polypropylene (PP) polymers, low density polypropylene (LDPP), high density polypropylene (HDPP), and combinations thereof are suitable for use as the polyolefin. Also disclosed as a polyolefin is ethylene vinyl acetate (EVA) copolymer. Another , polyolefin disclosed is a metallocene catalyzed polyolefin (i.e., plastomer) resin. Combinations of polyethylene polyolefins, polypropylene polyolefins, EVA copolymer, and plastomers are also disclosed for use as a polymeric resin. For example, mixtures or blends of low density polyethylene (LDPE), with or without other polymer materials, may be used. In addition, mixtures or blends of high density polyethylene (HDPE), with or without other polymer materials, may be used.

Polymeric resins may either be homopolymers or copolymers. In one embodiment, the polymeric resin is an olefin-copolymer. Non-limiting examples of olefin copolymers include polyethylene butylacrylate, polyethylene methacrylate, polyethylene vinyl acetate, and combinations thereof.

Also disclosed as a polymeric resin is a low density polyethylene (LDPE). The LDPE may have a density ranging from about <NUM>/cm<NUM> to about <NUM>/cm<NUM>. Also disclosed is a polymeric resin that is a linear low density polyethylene (LLDPE). The LLDPE may have a density ranging from about <NUM>/cm<NUM> to about <NUM>/cm<NUM>.

The synthetic paper of the present invention is one including one or more layers of a resin film formed from a composition comprising a high density polyethylene (HDPE) resin present in an amount of <NUM> percent to <NUM> percent by weight of the composition. The density of the HDPE may be from about <NUM>/cm3 to about <NUM>/cm3 and, in one embodiment, is greater than about <NUM>/cm3. The HDPE may have a molecular weight of at least about <NUM>,<NUM>. In one embodiment, the molecular weight of the HDPE is between about <NUM>,<NUM> and <NUM>,<NUM>,<NUM>. In another embodiment, the HDPE has a molecular weight of at least about <NUM>,<NUM>. In another embodiment, the HDPE has a molecular weight of at least about <NUM>,<NUM>. For example, the HDPE may have a molecular weight ranging from about <NUM>,<NUM>,<NUM> to about <NUM>,<NUM>,<NUM>. In yet another embodiment, the HDPE has a molecular weight of less than about <NUM>,<NUM>,<NUM>.

Also disclosed is a polymeric resin that is a very low density polyethylene (VLDPE). The density of the VLDPE is between about <NUM>/cm3 and about <NUM>/cm3. Also disclosed is polymeric resin that is a medium density polyethylene (MDPE). The density of the MDPE is between about <NUM>/cm3 and about <NUM>/cm3.

Also disclosed is a polymeric resin that is a recycled or biodegradable polyolefin resins. For example, such a polymeric resin may be a polyolefin resin constructed from bioplastics derived from renewable raw materials or plastics made from petrochemicals containing biodegradable additives that enhance biodegradation. Also disclosed is a polymeric resin that includes polyolefin resins made from aromatic polyesters (e.g., polyhydroxyalkanoates (PHAs) such as the poly-<NUM>-hydroxybutyrate (PHB), polyhydroxyvalerate (PHV), and polyhydroxyhexanoate (PHH), polylactic acid (PLA), polybutylene succinate (PBS), and polycaprolactone (PCL)); polyanhydrides; polyvinyl alcohol, start derivatives; or cellulose esters.

The high density polyethylene resin is present in an amount of <NUM> percent to <NUM> percent by weight of the composition. In another embodiment, the composition includes about <NUM> percent to about <NUM> percent of the polymeric resin, by weight of the composition.

The composition used to form the one or more layers of a resin film in a synthetic paper of the present invention is one comprising a particulate filler having a mean particle size of <NUM> to <NUM>. Hence, a composition of the invention includes a low aspect ratio filler material. Suitable low aspect ratio fillers include, but are not limited to, alkali metal and alkaline earth metal carbonates, sulphates and phosphates, and mixtures thereof. In one embodiment, the low aspect ratio filler material includes calcium carbonate, sodium carbonate, barium sulphate, calcium sulphate, sodium sulphate, sodium phosphate, potassium phosphate, calcium phosphate, and mixtures thereof. Other low aspect ratio fillers are also contemplated, e.g., talc, silica, mica, and the like. In one embodiment, the low aspect ratio filler includes calcium carbonate (CaCO<NUM>).

It is understood and herein contemplated that the particle size of the low aspect ratio filler has an effect on the properties of the resulting film. It is also understood and contemplated that a low aspect ratio filler may have particles therein that are diverse in size. As such, the mean particle size (or average particle size) is used to define the low aspect ratio filler described herein. The particulate filler employed is one having a mean particle size of <NUM> to <NUM>. The size of the particles in the low aspect ratio filler may be determined according to ASTM E2651-<NUM>, Standard Guide for Powder Particle Size Analysis. In yet another embodiment, the low aspect ratio filler has a mean particle size from about <NUM> microns to about <NUM> microns. In particular, the low aspect ratio filler may have a mean particle size of about <NUM> microns, about <NUM> microns, about <NUM> microns, or other specific sizes within the range of about <NUM> microns to about <NUM> microns.

In yet another embodiment, the mean particle size of the low aspect ratio filler is at least about <NUM> microns, but not more than <NUM> microns. For example, the mean particle size of the low aspect ratio filler may range from about <NUM> to about <NUM> microns, or other ranges therebetween. The low aspect ratio filler may be included in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, the composition includes about <NUM> percent about <NUM> percent of the low aspect ratio filler by weight of the composition. In another embodiment, the composition includes about <NUM> percent to about <NUM> percent of the low aspect ratio filler by weight of the composition. In yet another embodiment, the low aspect ratio filler is included in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. However, other ranges of the low aspect ratio filler are contemplated for use in the present invention depending on the amounts of the other components included in the composition, provided that the composition comprises the high density polyethylene resin present in an amount of <NUM> percent to <NUM> percent by weight of the composition and also the cyclic olefin copolymer. For example, the low aspect ratio filler may be included in an amount about <NUM> percent to about <NUM> percent, and about <NUM> percent to about <NUM> percent by weight of the composition.

Also disclosed is a composition that may include a polymeric resin including polyethylene, such as LDPE or LLDPE, and a low aspect ratio filler, such as CaCO<NUM>. In this instance polymeric resin may be present in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition and the low aspect ratio filler may uniformly dispersed in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one instance, the resin film is formed from a composition that includes about <NUM> percent to about <NUM> percent LDPE or LLDPE and about <NUM> percent to about <NUM> percent CaCO<NUM>. In this instance, the CaCO<NUM> may have a mean particle size from about <NUM> microns to about <NUM> microns.

The composition used to form the one or more layers of a resin film in a synthetic paper of the present invention is one comprising a cyclic olefin as a tear additive.

Further tear additives disclosed include block copolymers, alternating polymers, stereoblock copolymers, and combinations thereof. For example, the tear additive may be a branched (e.g., star, brush, or comb) or linear copolymer. In one instance, the copolymer can be a copolymer of poly(lactide), a poly(glycolide), a poly(lactide-co-glycolide), a poly(caprolactone), a poly(orthoester), a poly(phosphazene), a poly(hydroxybutyrate) a copolymer containing a poly(hydroxybutarate), a poly(lactide-co-caprolactone), a polycarbonate, a polyesteramide, a polyanhydride, a poly(dioxanone), a poly(alkylene alkylate), a copolymer of polyethylene glycol and a polyorthoester, a biodegradable polyurethane, a poly(amino acid), a polyamide, a polyesteramide, a polyetherester, a polyacetal, a polycyanoacrylate, a poly(oxyethylene)/poly(oxypropylene) copolymer, polyacetals, polyketals, polyphosphoesters, polyhydroxyvalerates or a copolymer containing a polyhydroxyvalerate, polyalkylene oxalates, polyalkylene succinates, poly(maleic acid), or combinations thereof. In one instance, the copolymer can be can be poly(lactide), <NUM>:<NUM> poly(lactide-co-glycolide) <NUM>:<NUM> poly(lactide-co-glycolide), <NUM>:<NUM> poly(lactide-co-glycolide), <NUM>:<NUM> poly(lactide-co-glycolide), <NUM>:<NUM> poly(lactide-co-glycolide), or combinations thereof, where the ratios are mole ratios.

Also disclosed is a resin film that is formed from a composition that includes a polymeric resin, a low aspect ratio filler, and a tear additive, where the tear additive includes a block copolymer, alternating polymer, stereoblock copolymer, or a combination thereof. In another instance, the low aspect ratio filler includes calcium carbonate (CaCO<NUM>) and is uniformly dispersed in the composition. In yet another instance, a resin film is formed from a composition that includes a polymeric resin and a tear additive, where the tear additive includes a block copolymer, alternating polymer, stereoblock copolymer, or a combination thereof.

The tear additive comprises a cyclic olefin copolymer ("COC"). As understood by those of ordinary skill in the art, COCs may be produced by copolymerization of ethylene with a cyclic olefin monomer. In this regard, the cyclic olefin monomers may be derivatives of cyclopentadiene or dicyclopentadiene. In one embodiment, the cyclic olefin monomers include norbornene, dihydrodicyclopentadiene, phenyl norbornene, tetracyclododecene, or combinations thereof. The COC to be used as the tear additive may also be produced by ring-opening metathesis polymerization of various cyclic monomers followed by hydrogenation (cyclic olefin polymers). In one aspect, the COC may be a chain copolymerization of cyclic monomers such as <NUM>,<NUM>,<NUM>-trinorborn-<NUM>-ene (norbornene) or <NUM>,<NUM>,<NUM>,<NUM>,4a,<NUM>,<NUM>,8a-octahydro-<NUM>,<NUM>:<NUM>,<NUM>-dimethanonaphthalene (tetracyclododecene) with ethane. In one embodiment, the tear additive may be a COC of ethylene and norbonene. In another embodiment, the COC is a <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, or <NUM>:<NUM> molar ratio of ethylene and norbonene.

As such, in one embodiment, the resin film is formed from a composition that includes a polymeric resin, a low aspect ratio filler, and a tear additive, where the tear additive includes a COC. In another embodiment, the low aspect ratio filler includes calcium carbonate (CaCO<NUM>) and is uniformly dispersed in the composition. In yet another embodiment, the resin film is formed from a composition that includes a polymeric resin and a tear additive, where the tear additive includes a COC.

The tear additive may be present in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, the tear additive may be present in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In another embodiment, the tear additive may be present in the composition in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In yet another embodiment, the composition includes about <NUM> percent to about <NUM> percent of the tear additive, by weight of the composition.

The compositions of the invention may also include "special effect agents. " Special effect agents refers to any agent that can create a visual effect including, but not limited to, colored pigments, pearlescent pigments, light interference pigments, matte additives, or other special effect pigments. Special effect agents may be included in the composition in amounts ranging from about <NUM> percent to about <NUM> percent by weight of the composition depending on the particular desired result of the additive. For example, the special effect agent may be included in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, the compositions of the invention include a matte additive in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In another embodiment, a colored pigment is included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In yet another embodiment, the compositions of the invention include a pearlescent pigment in an amount of about <NUM> percent to about <NUM> percent by weight of the composition.

The compositions of the invention may also include functional additives such as antistatic agents, anti-fog agents, flame retardants, desiccants, antioxidants, oxygen scavengers, ultraviolet inhibitors, moisture blockers, and combinations thereof. Suitable non-limiting examples of antistatic additives include fatty acid esters of polyethylene glycol, such as glycerol monostearate, whether present in a mixture or not with ethoxylated amines and alkyl amines or fatty acid amides, such as stearamide, with the possibility of being mixed with sliding additives, such as erucamide amides and oleamide.

As would be understood by those of ordinary skill in the art, antistatic agents are generally available in migratory and non-migratory chemistries. Both are independently contemplated for use in the compositions of the present invention. For example, in one embodiment, the antistatic agent is present in a migratory masterbatch such that the antistatic properties take affect when the final polymer is formed. More specifically, the low molecular weight antistatic agent begins to migrate to the polymer's surface to form a microscopically thin coating at which point the coating actively captures water vapor from the air. The captured water, in turn, becomes the conductor to dissipate static electricity. Should the antistatic agent present on the surface be wiped away through use, more of the antistatic agent migrates out of the polymer to replace it. Such anti-static agents may include amines or be amine-free depending on the end use of the synthetic paper. For example, antistatic agents including amines are not recommended for use for electronics packaging or packaging that includes or has contact with polycarbonates. When present, the amine may comprise about <NUM> percent to about <NUM> percent by weight of the antistatic agent. In another embodiment, the antistatic agent is present in a non-migratory masterbatch. Such a masterbatch is independent of atmospheric humidity and provides antistatic properties to the composition (and ultimately the synthetic paper) by forming static electricity percolating networks. In other words, without being bound by any particular theory, the agent itself is conductive and, if present in a sufficient amount, electricity can tunnel through the polymer providing that the gaps between the agent and the nonconductive polymer are of a size that allows such a tunneling effect.

Suitable non-limiting examples of antioxidants for use with the present invention include phenol-, aromatic amine-, sulfate-, mercaptan-, phosphite-, benzophenone- and its derivatives-, benzotriazol-, sterically obstructed amine-, salicylic acid-, chromo- and manganese salt-, phosphorus compound-based compounds, and combinations thereof.

Functional additives may be included in the composition in amounts ranging from about <NUM> percent to about <NUM> percent by weight of the composition depending on the particular desired result of the additive. For example, these types of additives may be included in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, the compositions of the invention include at least one desiccant in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In another embodiment, an antioxidant is included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In yet another embodiment, the compositions of the invention include an oxygen scavenger in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In still another embodiment, an ultraviolet inhibitor is included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In yet another embodiment, the compositions of the invention include at least one moisture blocker in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. Anti-fog agents, and flame retardants may each be included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. Migratory antistatic agents may be included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, the composition includes about <NUM> percent to about <NUM> percent by weight of a migratory antistatic agent. In another embodiment, the composition includes about <NUM> percent to about <NUM> percent by weight of a migratory antistatic agent. In yet another embodiment, the composition includes about <NUM> percent to about <NUM> percent by weight of a migratory antistatic agent. Non-migratory antistatic agents may be included in the compositions of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition.

Compatibilizer agents may also be included in the compositions of the invention. Suitable compatibilizer agents include, but are not limited to diblock SB styrene-butadiene copolymers, triblocks SBS or star and linear multiblocks or "graphitized" (grafted), multiblocks SB hydrogenated copolymers such as styrene-ethylene-butylene-styrene (SEBS), graphitized copolymers of polypropylene and polyethylene with styrene (S) or maleic anhydrous (MAH), such as PP-g-S, PP-g-MAH, PE-g-S, PE-g-MAH, and combinations thereof. When included compatibilizer agents may be included in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. In one embodiment, a compatibilizer agent is included in the composition of the invention in an amount of about <NUM> percent to about <NUM> percent by weight of the composition.

Antiblockage additives may be employed to prevent the film from sticking together. In this aspect, suitable antiblockage additives useful in the such compositions include, but are not limited to, porous and non-porous synthetic sylic with or without surface treatment, silicates, thin spheres of poly (methyl methacrylate) and silicone with the possibility of being mixed with sliding additives, such as erucamide amides and oleamide, or present in a mixture with fatty acid amides, such as stearamide. In one embodiment, the composition of the invention includes at least one antiblockage additive in an amount of about <NUM> percent to about <NUM> percent by weight of the composition. When present, the sliding additive is present in an amount of about <NUM> percent to about <NUM> percent by weight of the composition.

While in its simplest form, the synthetic paper of the present invention is formed from a single layer of resin film, where the resin film is formed from a composition of the invention. However, it is fully contemplated that the synthetic paper includes multiple layers of resin film, provided that the synthetic paper still is as defined in the claims. For example, the synthetic paper may include at least two layers. In one embodiment, the synthetic paper includes at least three layers. In another embodiment, the synthetic paper includes more than four layers. Indeed, the synthetic paper may include <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> or more layers.

Because the synthetic paper may include multiple layers of the resin film, it is understood that that the polymeric composition forming each layer may contribute to the visual and textural effects given to synthetic paper as well as the other physical attributes of the film given the intended use of the film. Accordingly, the composition used to form each layer of the synthetic paper is independent and can be different or the same as any one or more additional layers. In one aspect, each layer of the synthetic paper can include the same or different polyolefin resins. In one embodiment, the synthetic paper includes a plurality of layers where the compositions used to form each layer all include the same polymeric resin. In another embodiment, the synthetic paper includes a plurality of layers where the compositions used to form each layer all include different polymeric resins. In yet another embodiment, the synthetic paper includes a plurality of layers where at least one layer is formed from a composition that uses a different polymeric resin than the polymeric resin included in the composition used to form the other layer(s). For example, a synthetic paper is disclosed that includes at least two layers where a first layer is formed from a composition that includes low density polyethylene (LDPE) and a second layer is formed from a composition that includes linear low density polyethylene (LLDPE), high density polyethylene (HDPE), or any of other polymeric resins described above.

It is understood and herein contemplated that the individual layers of the synthetic paper may include the same or different composition and that the ratio of individual layers may be modified to achieve different visual effects. For example, when the synthetic paper includes two layers, each layer may comprise about <NUM> percent by weight of the synthetic paper. Alternatively, when the synthetic paper includes two layers, each layer may comprise <NUM>, <NUM>,<NUM> ,<NUM>, <NUM>,<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> percent by weight of the synthetic paper while the remaining layer includes the remaining percentage of the synthetic paper. Similarly, when the synthetic paper includes three layers, each layer may comprise the same portion (i.e., a <NUM>/<NUM> portion) of the weight of the synthetic paper or be differently proportioned such that at most two of the layers comprise the same amount while the remaining layer includes a different weight percentage of the overall weight of the synthetic paper or all three layers comprise different weight percentages of the overall weight of the synthetic paper. For example, it is contemplated that the first (i.e., the outer) layer and the third layer (i.e., innermost layer) may each comprise <NUM> percent by weight of the synthetic paper (a total of <NUM> percent) while the second (middle or core layer) includes the remaining <NUM> percent of the overall weight of the synthetic paper. In this aspect, any combination of layer weight ratios can exist in the synthetic paper, including, but not limited to, an outer:middle:inner percentage of <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>;<NUM>: <NUM>:<NUM>; <NUM>:<NUM>: <NUM>; <NUM>:<NUM>:<NUM>; <NUM>:<NUM>:<NUM>; or <NUM>:<NUM>:<NUM> or any other combination.

It is understood and herein contemplated that the relative compositions used for building multiple layers of synthetic paper mainly vary with the application and type of layer, i.e., outer, inner, or core. For example, the middle or core layer may be composed of about <NUM> percent to about <NUM> percent polyolefin resin, <NUM> percent to about <NUM> percent low aspect ratio filler, and about <NUM> percent to about <NUM> percent tear additive. In addition, one layer may include a tear additive and another layer may not.

As discussed previously, a special effect agent is an agent that can create a visual effect. As such, special effect agents may be used in a synthetic paper including a single layer of resin film. In addition, if the resin film includes multiple layers, special effect agents can be incorporated into any layer of the multilayered polymeric film. For example, in one embodiment, the synthetic paper of the present invention includes at least two layers of resin film where both layers include a composition of the invention that has a special effect agent dispersed therein. In another embodiment, the synthetic paper of the present invention may include more than two layers, e.g., three layers, where each of the second and third layers is formed from a composition including a special effect agent. In yet another embodiment, the synthetic paper of the present invention includes three layers, where each of the layers is formed from a composition including a special effect agent. In this aspect, the special effect agent included in each layer may be the same or different.

The synthetic paper can be any thickness needed given the desired application. Thickness can be determined by the number of layers and/or the thickness of the one or more individual layers. In one aspect, the thickness of the synthetic paper can be generally in the range of about <NUM> mils to about <NUM> mils. In one embodiment, the synthetic paper may have a thickness of about <NUM> mils to about <NUM> mils. In another embodiment, the synthetic paper may have a thickness of about <NUM> mils to about <NUM> mils. If the synthetic paper includes multiple layers, the thickness of each layer may be the same or different. For example, if the synthetic paper has an overall thickness of about <NUM> mil but includes multiple layers, the thickness of each layer may be about <NUM> mils. Alternatively, if the synthetic paper has an overall thickness of about <NUM> mils but includes multiple layers, the thickness of the first layer may be about <NUM> mils and the thickness of the second layer may be about <NUM> mils.

If the synthetic paper includes more than one layer, each layer may account for <NUM>, <NUM>,<NUM> ,<NUM>, <NUM>,<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> percent of the total thickness of the synthetic paper while the remaining layers includes the remaining percentage of the synthetic paper.

In one embodiment, the synthetic paper includes at least two layers where the first layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper and the second layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper. In another embodiment, the first layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper and the second layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper. In still another embodiment, the first layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper and the second layer accounts for about <NUM> percent to about <NUM> percent of the total thickness of the synthetic paper.

The synthetic paper may be produced with blown or cast extrusion processes. The order and method of mixing the components in the compositions used to prepare the films of the present invention is not critical. In one embodiment, the components can be combined simultaneously.

The synthetic papers of the present invention may also be treated with a glossy surface treatment or hazy surface treatment, depending on the intended end use. For example, both water borne coatings and non-water borne coatings can be used to coat the synthetic papers of the present invention. The formulation of water borne coating may include acrylic resin, isopropanol, polyvinyl alcohol, clays, an anti-static agent, <NUM> percent aqueous ammonia, pure water, and vinyl acetate.

In addition, the synthetic papers of the present invention have a surface that will accept most common printing methods and ink systems. As such, it is contemplated that flexography, gravure, letterpress, screen or offset presses will be used to print line work or multi-color process on the synthetic papers of the present invention.

Without being bound to any particular theory, it is believed that the use of a low aspect ratio filler in the compositions of the invention improve the dead fold properties of the resulting synthetic paper. A synthetic paper of the present invention is one that has a synthetic paper has a dead fold angle of <NUM>° to <NUM>°. "Dead fold" refers to the synthetic paper's ability to retain a fold or crease. Typically, materials with superior dead fold properties include metal foils, paper, polystyrene and PVC. A conventional test for dead fold property may be conducted by making a <NUM>° fold in the material at ambient temperature and then measuring the angle to which the fold opens after a period of time. Lower or smaller angles are desirable since this indicates greater dead fold retention. For the purposes of this disclosure, a dead fold angle is intended to refer to the angle of the fold after a period of about five minutes.

As shown in <FIG>, virgin HDPE film with a thickness of <NUM> mils has a dead fold angle of about <NUM>° after five minutes. In comparison, a piece of copy paper with a thickness of about <NUM> mils has a dead fold angle of about <NUM>° after five minutes. The synthetic papers of the present invention exhibit improved dead fold properties over virgin polyethylene film and comparable dead fold properties to copy paper. More specifically, the synthetic paper of the present invention may have a dead fold angle after five minutes of about <NUM>° or less. In one embodiment, the dead fold angle of the synthetic paper of the present invention after a period of five minutes is about <NUM>° to about <NUM>°. In another embodiment, the synthetic paper of the present invention has a dead fold angle after five minutes of about <NUM>° to about <NUM>°.

Without being bound by any particular theory, it is believed that the use of a tear additive in the compositions of the invention results in synthetic paper that allows for the paper to be torn with minimal or no stretching of the synthetic paper without the need for a priming cut. In this regard, the tear strength can be adjusted by adjusting the let-down ratio of the tear additive in the composition (i.e., the weight percent of tear additive by weight of the total composition). In one embodiment, the Elmendorf Tear Strength (ASTM D1922) is <NUM> mN to <NUM> mN in a transverse direction. As used herein, transverse direction means a direction perpendicular to the direction of working. In another embodiment, when formed using HDPE, the synthetic paper of the present invention may have an Elmendorf Tear Strength ranging from about <NUM> mN to about <NUM> mN in the transverse direction.

The Elmendorf Tear Strength (ASTM D1922) ranges from about <NUM> mN to about <NUM> mN in the machine direction. As used herein, machine direction means a direction parallel to the direction of working. In another embodiment, the Elmendorf Tear Strength ranges from about <NUM> mN to about <NUM> mN in the machine direction. In yet another embodiment, the Elmendorf Tear Strength ranges from about <NUM> mN to about <NUM> mN in the machine direction. For example, when formed using LDPE, the synthetic paper of the present invention may have an Elmendorf Tear Strength ranging from about <NUM> mN to about <NUM> mN in the machine direction. In one embodiment, when formed using LDPE, the synthetic paper of the present invention may have an Elmendorf Tear Strength ranging from about <NUM> mN to about <NUM> mN in the machine direction. In another embodiment, when formed using HDPE, the synthetic paper of the present invention may have an Elmendorf Tear Strength ranging from about <NUM> mN to about <NUM> mN in the machine direction. In another embodiment, when formed using HDPE, the synthetic paper of the present invention may have an Elmendorf Tear Strength ranging from about <NUM> mN to about <NUM> mN in the machine direction.

The tear properties of the synthetic paper of the present invention may also be measured in comparison to virgin film. For example, when compared to virgin LLDPE film, the synthetic paper of the present invention may have a drop in Elmendorf Tear Strength of at least about <NUM> percent in the transverse direction and at least about <NUM> percent in the machine direction. In one embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LLDPE film. In another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LLDPE film. In yet another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LLDPE film. In another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent in the machine direction of the Elmendorf Tear Strength of virgin LLDPE film. In still another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LLDPE film. In yet another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LLDPE film.

When compared to virgin LDPE film, a synthetic paper, when formed from a resin film including LDPE and a tear additive, may have a drop in Elmendorf Tear Strength of at least about <NUM> percent in the transverse direction and at least about <NUM> percent in the machine direction. In one embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In yet another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In still another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In yet another embodiment, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film.

When compared to virgin LDPE film, a synthetic paper, when formed from a resin film including LDPE, a low aspect ratio filler, and a tear additive, may have a drop in Elmendorf Tear Strength of at least about <NUM> percent in the transverse direction. In one embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In yet another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In still another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film. In yet another embodiment, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film.

When compared to virgin HDPE film, the synthetic paper of the present invention, formed from a resin film including HDPE, a low aspect ratio filler, and a tear additive, may have a drop in Elmendorf Tear Strength of at least about <NUM> percent in the machine direction. In one embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin HDPE film. In another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin HDPE film. In yet another embodiment, in the transverse direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin HDPE film. In another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin HDPE film. In still another embodiment, in the machine direction, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin HDPE film. In yet another embodiment, the Elmendorf Tear Strength of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent of the Elmendorf Tear Strength of virgin LDPE film.

In addition, tearing the synthetic papers of the present invention occurs with less noise. In one embodiment, tearing the synthetic paper of the present invention is at least <NUM> percent quieter than tearing copy or bond paper. As a result, the synthetic papers of the present invention are useful for packaging in movie theaters, public rest rooms, and the like.

The synthetic paper of the present invention has superior water, oil, and grease resistance. Another significant advantage of the synthetic papers of the present invention is the improved oxygen and moisture barrier properties. The synthetic papers of the present invention provide about <NUM> to about <NUM> percent improvement in oxygen barrier and up to about <NUM> percent improvement in moisture barrier properties relative to uncoated packaging material. In other words, the synthetic papers of the present invention have a similar MVTR value to that of waxed paper.

The moisture vapor transmission of a synthetic paper of the present invention may be expressed in terms of absorption, e.g., weight gain or size gain over a period of time at a specific conditions, and transmission, e.g., moisture vapor transmission rate (MVTR) according to ASTM E96-<NUM>. MVTR refers to the mass of water vapor that diffused into a material of a given thickness per unit area per unit time at a specific temperature and humidity differential.

Weight changes of synthetic paper monitored over a period of seven weeks in <NUM> percent relative humidity and <NUM>°F help to demonstrate that the synthetic papers of the present invention have comparable water resistance to conventional wax paper. In one embodiment, the synthetic papers of the present invention have a weight gain of about <NUM> grams or less after seven weeks. In another embodiment, the synthetic papers of the present invention have a weight gain of about <NUM> grams or less after a seven-week storage period. In still another embodiment, the weight gain of the synthetic papers of the present invention is about <NUM> grams or less after seven weeks. In yet another embodiment, the weight gain is about <NUM> grams or less after a seven-week period. The synthetic papers of the present invention preferably have a weight gain of about <NUM> grams or less over a seven-week storage period.

The synthetic papers of the present invention may be about <NUM> to about <NUM> percent opaque. In one embodiment, the opacity of the synthetic paper of the present invention is about <NUM> percent to about <NUM> percent. In still another embodiment, the synthetic papers of the present invention may be about <NUM> to about <NUM> percent opaque.

As mentioned above, recycled or biodegradable polyolefins may be used in the compositions that form the resin films. Thus, it is contemplated that the synthetic papers of the present invention may be formulated to be completely recyclable.

The papers manufactured according to the present invention can be applied to the field of printing, packaging, and decoration. For example, the synthetic papers of the present invention may be used in food, deli, and meat wrap, bakery packaging, chewing gum packaging, condiment / sweetener packets, personal care packets, snack bag pouches, gift wrap, floral wrap, craft application, concrete bags, and merchandise bags. In fact, the synthetic paper of the present invention reduces or eliminates grease stains as compared to conventional paper food wraps and prevents the migration of chemicals and waxes into foods.

The following non-limiting examples are merely illustrative of preferred embodiments of the present invention, and are not to be construed as limiting the invention, the scope of which is defined by the appended claims.

Compositions of the invention including a polyolefin resin and a low ratio aspect filler were formed as shown in Table <NUM> below:.

As shown in Table <NUM>, when compositions A - F were tested in the machine direction (MD) and transverse direction (TD), the lower particle size in the low aspect ratio filler produced the highest percent elongation and tensile strength.

In addition, there are not significant differences in the tested properties between compositions A and C or D and F in the machine or transverse directions.

Compositions of the invention including different types of polyolefin resin and varying amounts of tear additive were used to form resin films according to the present invention. In each case, the polyolefin resin was used in an amount of <NUM> percent to <NUM> percent by weight of the composition.

<FIG> shows the effects of the tear additive in varying amounts on LLDPE film. In particular, at two percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At five percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At ten percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction.

<FIG> shows the effects of the tear additive in varying amounts on LDPE film. In particular, at two percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At five percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At ten percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction.

<FIG> shows the effects of the tear additive in varying amounts on HDPE film. In particular, at five percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and no drop in the Elmendorf tear strength in the transverse direction. At ten percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and no drop in the Elmendorf tear strength in the transverse direction. There was no effect on the Elmendorf tear strength in either the machine direction or transverse direction at <NUM> percent loading.

Compositions of the invention including polyolefin resin, a color additive, varying amounts of tear additive, and low ratio aspect filler were used to form resin films according to the present invention. In each case, the polyolefin resin was LDPE, which was included in an amount of <NUM> percent by weight of the composition, the color additive was brown masterbatch, which was included in an amount of <NUM> percent by weight of the composition, and the low aspect ratio filler was calcium carbonate with an average particle size of <NUM>, which was included in an amount of <NUM> percent by weight of the composition.

<FIG> shows the effects of the tear additive. In particular, at two percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and no drop in the Elmendorf tear strength in the transverse direction. At five percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At ten percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction.

In comparing <FIG> with <FIG>, the testing shows that a composition that includes LDPE, a low aspect ratio filler, and the tear additive forms a resin film that has superior tear properties over that of a composition that includes only LDPE and the tear additive.

Compositions of the invention including polyolefin resin, varying amounts of tear additive, and low ratio aspect filler were used to form resin films according to the present invention. In each case, the polyolefin resin was HDPE, which was included in an amount of <NUM> percent by weight of the composition and the low aspect ratio filler was calcium carbonate with an average particle size of <NUM>, which was included in an amount of <NUM> percent by weight of the composition. The control included only HDPE, but no low aspect ratio filler.

<FIG> and <FIG> show that the results obtained in Example <NUM> with LDPE are not realized with HDPE. In particular, at two percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and no drop in the Elmendorf tear strength in the transverse direction. At five percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction. At ten percent loading of the tear additive, there was a <NUM> percent drop in Elmendorf tear strength in the machine direction and a <NUM> percent drop in the Elmendorf tear strength in the transverse direction.

Claim 1:
A synthetic paper including one or more layers of a resin film formed from a composition comprising:
a high density polyethylene resin present in an amount of <NUM> percent to <NUM> percent by weight of the composition;
a particulate filler having a mean particle size of <NUM> to <NUM>; and
a cyclic olefin copolymer produced by copolymerization of ethylene with at least one cyclic olefin monomer, wherein the at least one cyclic olefin monomer comprises at least one of: cyclopentadiene, a cyclopentadiene derivative, dicyclopentadiene, a dicyclopentadiene derivative, norbomene, dihydrodicyclopentadiene, phenyl norbornene, and tetracyclododecene, or a combination thereof,
wherein the synthetic paper has:
- a dead fold angle of <NUM>° to <NUM>° when measured by making a <NUM>°-fold in the material at ambient temperature and then measuring the angle to which the fold opens after a period of time; and
- an Elmendorf tear strength of <NUM> mN to <NUM> mN in a transverse direction when measured according to ASTM D1922.