TW200424241A - Film suitable for food packaging - Google Patents

Abstract

Controlled permeability films are described that comprise at least one film-forming polymer and an inert, nonporous filler material having an average particle size such that the ratio of the average particle size of the filler to the film thickness is 0.67 to 0.99. Packages comprising such a controlled permeability film, and methods for making the film and using it to improve the storage life of a perishable article are also described.

Description

发明, Description of the invention: [Item ^ Ming belongs to ^ Technique ^ Field ^]

This patent application claims priority from US provisional patent applications USSN 60 / 360,447 (please requested on February 28, 2002) and USSN 60 / 368,306 (filed on March 28, 2002). 1 明 领 娀 The present invention relates to a plastic film with controlled permeability characteristics. The film of the present invention is particularly suitable for packaging. The present invention also relates to a method for manufacturing the thin film, a packaging body including the thin film, and a method for improving the shelf life of, for example, fresh agricultural products σσ and perishable articles. C Prior technology; j Circulation and sales of today's products, using a large number of different packaging materials. A major type of packaging material is plastic film. In order to meet the special performance requirements of various packaging applications and materials being packaged, there are many different types of plastic films in composition and structure. The preservation of freshness, flavor, texture and edible quality during consumption during packaging presents freshly cut agricultural products, such as fruits and vegetables, presenting particular challenges. It has been found that when the respiration and ripening effects of such agricultural products can be appropriately reduced and the growth of pathogenic bacteria can be suppressed, the shelf life of packaged agricultural products can be extended and the quality deterioration and undesired phenomena such as putrid odor can be reduced. In the art, special requirements and recommended conditions for long-term storage, especially in the form of all fresh fruits and vegetables, are known. One of the factors that significantly affect the shelf life of packaged agricultural products is the presence of gases, including oxygen and carbon dioxide. Depending on storage conditions, such as temperature and relative humidity, f agricultural products have their specific optimized oxygen content, carbon dioxide concentration, and relative concentration of carbon dioxide with respect to oxygen. Under these concentration conditions5, it can properly prevent breathing Function and can maintain the quality to the maximum extent possible. In order to provide improved storage conditions for specific agricultural products, including favorable concentrations of oxygen and carbon dioxide ', it has been proposed to have a controlled gas permeability of the limbs and an improved plastic film for atmospheric packaging. For example, US Patent No. 4,879,078 discloses a controlled packaging atmospheric film that includes a polymer and 36 to 60 weight percent inert filler. This film is uniaxially stretched to provide a permeability range of 5,000 to 10,000 cubic centimeters per square inch · atmospheric pressure-days of carbon dioxide and oxygen. However, relatively high levels of fillers and the need for a stretching step are disadvantageous. International Patent Application WO 94/04655 discloses a multilayer film having an oxygen permeability ranging from about 150 to 450 cubic centimeters / 100 square inches-atmospheric pressure_days or more up to about 1,000 cubic centimeters / 丨 00 square inches-atmospheric pressure-day, the membrane includes a first outer layer of elastomer and a second layer of single-site catalyst polyethylene. Disadvantages of such films include their limited range of penetration and the requirements for multilayer structures. For ecological and / or economic reasons, it is desirable that controlled permeability characteristics be obtained as a single film. International patent applications WO 92/02580, WO 95/07949, and wo 99/33658 respectively disclose films with controlled permeability, which include films formed from polymers and filler particles, the filler particles being inherently The film thickness is large. Desire 6 200424241 To further improve the characteristics of such films, such as the appearance, including visual appearance, printability and safety. Film that can be easily printed with excellent transparency and is especially suitable for retail packaging. There is still a need for plastic films suitable for packaging applications, especially for such applications where perishable items are involved. This film can provide appropriate controlled penetration characteristics that are suitable for extending without sacrificing security. Shelf life of packaged items. Such controlled transmissive films also have excellent optical and tactile properties, as well as good mechanical properties to provide proper protection for packaged items. 10 [Development Content L] Man Jg is summarized in a specific embodiment. The present invention is a film with controlled permeability, including A · —polymeric film, which has an inherent thickness, and B · — The milled, non-porous inert filler is incorporated into the film and has an average particle size such that the ratio of the average particle size of the filler to the thickness of the film is 067 to 0099. In another specific embodiment, the present invention is a film with controlled permeability, comprising: 2〇A · a polymerizable film, which has an inherent thickness, and B • a non-porous, inert particle filling The filler is blended into the "Hai film" and has an average particle size, so that the ratio of the average particle size of the filler to the film thickness is 0.67 to 0.99, 200424241. The particle filler in the film It is subjected to a compressive force treatment, causing at least a part of the particulate filler to be crushed. In another specific embodiment, the present invention is a compressed, controlled permeability film, including: 5 Α · a polymerizable A film having an inherent thickness and B · a non-porous, inert particulate filler, which is incorporated into the film and has an average particle size such that the average particle size of the filler relative to The ratio of the film thickness is 067 to 099, and at least a part of the particulate filler is crushed.

10 jh SL In another specific embodiment, the present invention is a method for manufacturing a material with controlled permeability. The method includes the following steps: filling a film-forming polymer with an inert, non-porous particle Blended, the particle filler has an average particle size; B · formed from a blend of (Λ >) having a film with an inherent film thickness, so that the ratio of the average particle size of the filler to the film thickness is 0.67 to 0.99; And C. subjecting the film of (B) to a compressive force such that at least a portion of the particulate filler is broken by the instrument. 20 In another embodiment, the present invention is a method for manufacturing a film having controlled penetration. A method comprising the following steps: A • Blending a film-forming polymer with an inert, non-porous, milled particulate filler having an average particle size; 200424241 B. A film having an inherent film thickness is formed from the blend of (A), so that the ratio of the average particle size of Hi to the film thickness is 0.67 to 0.99. In the case of Babetal, the present invention includes a film having controlled penetration I * Born The packaging body of the film, basin φ for women and girls ^ The film has an inherent thickness and contains an inert, ..., holes &, crushed particles are filled together! The particle filler has an average particle size, the secret filling The ratio of the average age scale to the intrinsic film thickness is between 0 67 and 0 99. 10 15 In another embodiment, the present invention is a method for extending the shelf life of a perishable article, such as Fresh produce by packaging at least a portion of the article in a controlled permeability film, wherein the film has an inherent thickness and contains an inert, non-porous, milled particulate filler The particle filler has an average particle size, and the ratio of the average particle size of the particle filler to the inherent film thickness is bounded between 0.67 and 0.99. DETAILED DESCRIPTION OF THE INVENTION The following special terms used in the foregoing , Has a specific meaning. The singular generally includes the majority and the majority generally includes the singular. The word "comprising" means "including." 20 The term "copolymer" means a polymer, two of which do not The monomers polymerize to form a copolymer. The term "heterogeneous copolymer" means a polymer in which at least two different monomers are polymerized to form this heterogeneous copolymer. This heterogeneous copolymer includes, for example, copolymers, terpolymers, and the like .

9 200424241 The term "membrane" means a flat item and includes pieces, strips, tapes and ribbons. The / 3 ratio is the ratio of carbon dioxide permeability to oxygen permeability. The term "non-porous" is used to describe an article, such as 5 filler particles, which does not have natural holes, gaps, channels or similar pathways, and extends from the surface of the mouth to the other of the article-Table ^ , Or in the case of a spherical or other surface object, extending from one point on the surface of the article to another point on the surface of the article. The passage of a porous article is large enough to allow small molecules of gas or liquid to pass through the article, such as oxygen, nitrogen, water, benzene, and the like. Non-porous articles include porous articles with blocked or blocked passages, such as hydrated inorganics. The terms "milled," "milled," and "milled," and similar terms are used to describe a non-porous article, such as filler particles, which has holes, spaces, channels, or similar A passage extending from the surface B of one of the articles to the other surface of the article so that gas or liquid Zhao can pass through the article; holes, gaps, etc. in the article are the result of activation of the article, such as passing the article through a sufficient size The compressive force is such that one or more such pathways can be created in the article. The term "activated or activated" and similar terminology are intended to mean that by any means, a pathway is created in a non-porous article such as filler particles, but generally by applying a compressive force to the article. The word mouth thickness means a single-layer film or a multi-layer film, one layer, the thickness or measurement of the second juice. The inherent film thickness is the film without fillers, and the dryness is the weight of the film (units) It is calculated by multiplying the density of the film by 10 200424241 degrees (g / cm3, g / cm3). The density of the film is the weight percentage of the polymer used to make gadolinium and the density of the polymer. Product, plus the weight percent of filler and the product of filler density. 5 Unless otherwise stated, all parts and percentages are by weight. Unless otherwise specified, any given range includes the endpoint used to describe the range. In addition, for example, all values in the range, if there is an interval of at least two units between any smaller value and any larger value, it includes an increment of one unit from the lowest value to the higher value All values. For example 10 and θ, if the amount of the component or a method variable such as temperature, pressure, etc. is 10 to 125, preferably 30 to 75, and more preferably 40 to 60, which means, for example, The values of 20 to 100, 35 to 70, and 50 to 55 are clearly enumerated and included in this description. For values less than 1, a unit can be regarded as 0.0001, 0001, 0.001, or 01, as applicable. It depends on the content 15. These are only examples of what is specifically desired between all of the lowest and highest values listed and all possible combinations of values specifically enumerated in this specification. Surprisingly, it has been found to include At least one film forming a polymer and a film of an inert, non-porous filler material, which can be treated through an activation step to effectively improve and control the oxygen and / or carbon dioxide permeability of the film. The filler material Has an average particle size such that the ratio of the average particle size of the filler material to the inherent thickness of the film is 0.67 to 0.99. The oxygen and / or carbon dioxide permeability of the film can be effectively adjusted to match the specific packaging product's Controlled Gas environment requirements or advice, such as 11 200424241 to extend the shelf life of agricultural products. The controlled permeability film of the present invention can be easily printed and has excellent optical and mechanical properties. In this article, The film can be provided in a cost-effective manner. The present invention provides single-layer and multi-layer films, in which at least one layer of the single-layer film or the multilayer film includes at least one film-forming polymer, and (ii)-inert, A non-porous filler material. The filler material has an average particle size such that the ratio of the average size of the filler to the film thickness is 0.67 to 0.99. The gas permeability of the film is activated by a Steps to improve. The film or film layer that has been treated with the activation step means a film with controlled permeability or a layer with controlled permeability, which is also the subject of the present invention. In multilayer films, additional layers are selected to enable or enhance specific film characteristics, such as thermal adhesion, heat sealability, and / or structural properties, but do not substantially interfere with penetration, Controlled permeability characteristics of the layers. Where appropriate, the multilayer film of the present invention may include one or more adhesive layers. Preferably, the additional layer system 15 is selected so as not to substantially interfere or substantially negatively affect the controlled permeability characteristics of the controlled permeability layer. For biological and / or economic reasons, the films of the present invention generally have as few layers as possible that meet the desired and / or required performance attributes. The preferred film structure of the present invention is a single-layer, two-layer or three-layer film, and preferably a single-layer film. > Q.-In a specific embodiment, the multilayer film of the present invention comprises 2 to about 7 layers, at least one layer, preferably one layer, comprising at least one film-forming polymer and an inert, non-porous filler Material, the filler material has an average particle size such that the ratio of the average particle size of the filler material to the inherent thickness of the layer is 0.67 to 0.99. In another specific implementation example 12 200424241, the multilayer film of the present invention includes 2 to about 7 layers, at least one layer, preferably one layer, comprising at least one film-forming polymer and an inert, non-porous filler material, The filler material has an average particle size such that the ratio of the average particle size of the filler material to the inherent thickness of the multilayer film of 5 degrees is 0.67 to 0.99. These multilayer films are generally laminates constructed using conventional techniques such as thermal or adhesive lamination, or extrusion coating. In specific embodiments where the ratio of the average particle size of the filler material to the inherent thickness of the layer is 0.67 to 0.99, this layer is generally activated before bonding to other layers of the film. In a specific example where the ratio of the average particle size of the filler material to the inherent thickness of the multilayer film is 0.67 to 0.99, the activation is performed after the multilayer film is formed. The activation step is to improve the gas permeability of the film or layer, which contains at least one film-forming polymer, and (Π)-an inert, non-porous filler material, the average of the filler material The ratio of the particle size to the intrinsic thickness of the film or layer 15 is from 0.67 to 0.99. Typical activation steps include pressure treatment, heat treatment, or a combination of these treatments. Compared to a film or layer containing an inactive, inert, porous filler, the activation step generally increases the gas permeability of the film or layer, especially the oxygen transfer rate. In other words, a film containing, for example, about 0.01 to 15 weight percent of an activated, inert, non-porous 20 filler material is compared to a film that is similar in all parts except without activation, Shows increased gas permeability. Furthermore, the activation step can increase the carbon dioxide transmission rate, but at least does not affect the water vapor transmission rate at low filler concentrations (e.g., 0.001 to 0.025). Advantageously, the desired controlled permeability characteristics can be obtained without stretching the film. 13 200424241 In a preferred embodiment, the activation step includes subjecting a film comprising at least one layer to a compressive force treatment, the layer including at least one film-forming polymer and a filler, the filler having an average particle size, The ratio of the average particle size of the filler material to the intrinsic thickness of the film is 0.667 to 0.99, and the compressive force treatment is performed, for example, by bringing the film into contact with a pressure plate or a roller. For example, the pressure treatment may be performed by passing the film between pressure rollers, where it may be heated as required. The membrane can be fully or partially activated, for example, only a portion of the width of the membrane, or every other segment of the length of the membrane, or a designated area within the area of the membrane, is subjected to a compressive force treatment. 10 The compressive force or pressure range should exceed the compressive strength of the filler particles. The range of this force is generally 2.5 to 100 kg, preferably 5 to 75 kg. The compressive force should be sufficient to at least partially crush the filler particles, such as cracks, holes, or channels within the filler particles that extend from one surface of the particles to the other surface of the particles. The contacting step may be performed at normal temperature or high temperature. Preferably, the 15 temperature is between room temperature and the melting point of the polymer having the highest melting point used to prepare the film, and is preferably higher than the highest melting point used to prepare a film or layer with controlled permeability. The polymer has a low melting point or softening point of 0 to 5 C. Preferably, the controlled-permeability membrane of the present invention has been treated with an activation step, or it includes at least one layer that has been treated with this step, with a ratio ranging from 20 to 0.8 to 3.5, more preferably 0.8 to 25, more preferably 0.8 to 2.0, and most preferably 0.8 to K5. Methods and suitable equipment for determining oxygen and carbon dioxide transmission rates are known in the art, such as ASTM D3985. 14 200424241 The film of the present invention can have any thickness or measure suitable for the intended use of the film. For economic and / or biological reasons, it is desirable to minimize film thickness. The typical thickness of a single-layer film according to the present invention ranges from about micrometers (/ zm) (0.4 mils) to about 125 micrometers (5 mils), preferably about * 5 30 micrometers (L2 mils) To about 75 microns (3 mils). The general total thickness of the multilayer film according to the present invention ranges from about 25 microns (1 mil) to about 250 microns (10 mils). Films with controlled permeability according to the invention, whose outer and / or inner surfaces are available for printing. The printing of the film can be performed by, for example, a flexographic or rotary gravure device, preferably after activation. If appropriate, the ink used is suitable for food packaging. Advantageously, the film having controlled permeability according to the present invention is designed to have excellent optical transparency, flexibility and toughness. The film of the present invention can be prepared by any suitable manufacturing method, and its characteristics can be designed to match any particular end application. Suitable manufacturing methods 15 include, for example, blown film extrusion, flat die extrusion, coextrusion, extrusion coating, and lamination techniques. The film can be made in any suitable form for wholesale and retail, such as roll stock, and can be used on conventional equipment. Preferably, the film system according to the present invention is designed to be easily machined at a linear speed that is cost effective. 20 Film-forming polymers can be in any suitable form and generally include, but are not limited to, homopolymers, copolymers, heteropolymers, such as block, graft, random, alternating copolymers, or heteropolymers. "Polymer," includes all possible geometrical configurations of a material, including cis, syndiotactic and random symmetries. Suitable polymer forms include, for example, polyolefins such as Otomo and thread 15 200424241 Homopolymers, copolymers, heteropolymers and blends of α-mono-olefins having at least 3 carbon atoms, the α-mono-olefins preferably have 3 to 10 carbon atoms. They can be used in the present invention Examples of homopolymers are polyethylene, polypropylene and poly (1-butene). Representative examples of suitable copolymers are: 5 ethylene / propylene, ethylene / butene, ethylene / pentene, ethylene / hexene , Ethylene / heptene and ethylene / octene copolymers. Suitable types of polyethylene include, but are not limited to, high pressure low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE). Examples of other homopolymers, copolymers, and heteropolymers that can be used are polyesters, including polyethylene terephthalate · 10 formate and polybutylene terephthalate, nylon, polystyrene, and ethylene polymers Materials, such as polyethylene gas, polyvinyl acetate, ethylene Acid vinyl ester copolymer and ethylene-vinyl alcohol copolymer, ethylene methacrylic acid copolymer (ionomer), ethylene / styrene heteropolymer, polyepoxide polymer, and polycarbonate. Representative of blends Examples are blends of homopolymers, such as 15 polyethylene or polypropylene, and copolymers, such as ethylene / butene or ethene / octane and copolymers. The choice of film-forming polymer should be compatible with The requirements of the film are consistent, such as with processability and physical properties. Preferably, the polymer forming the film is suitable for food packaging applications and meets individual requirements set by the competent authority. 20 Such preferred polymers include , Such as polyethylene polymers, polypropylene polymers, ethylene vinyl alcohol copolymers, and ethylene vinyl acetate copolymers. — In a composition that is applied to form a film with controlled permeability according to the present invention, the film is formed. The amount of the polymer is preferably 99.99% by weight or less (based on the amount of the film-forming polymer and filler in the film or layer). 16 200424241 Preferably, the amount of the film-forming polymer is 85 weight Fractional or higher, more preferably 90% by weight or higher, and most preferably 96% by weight or higher. In a particularly preferred embodiment, the amount of the film-forming polymer ranges from 98% by weight to 99 · 975 weight percent based on the combined weight of the film and the filler. The filler material used in the present invention is inert to the film-forming polymer (s), which means that the filler material will not chemically interfere Or negatively affect the film. Suitable fillers are organic, or preferably inorganic, particulate materials. Fillers can be natural or synthetic materials. Filler particles are non-porous. Preferably, the particles are essentially It is spherical and has an aspect ratio of about 1 to about 2. Preferably, the filler has a suitably low compressive strength so that it can be crushed fairly easily during activation, but during mixing or film manufacturing, it is substantially got damage. Suitable filler materials have an average particle size ranging from 30 to 70 microns. For single-layer films, the average particle size typically ranges from about 8 15 to about 1.13 microns. Non-porous filler materials suitable for use in the present invention include, for example, pumice, tuff, rhyolite, quartz andesite, reticulated volcanic slag, volcanic butterfly, perlite, coal, oxide stone, metal oxides such as oxides, such as Barium sulfate, such as carbonate carbonate and clay. A particularly good filler 20 is an inorganic substance, a spherical microcrystalline material, such as non-porous oxidized stone, such as glass beads. It is also foreseeable to use mixtures of different filler materials. Advantageously, the filler material is uniformly dispersed throughout the film-forming polymer used to make the films and / or layers of the present invention. 17 200424241 In one of the more common embodiments of the present invention, inert, non-porous filler particles are crushed prior to blending with the film-forming polymer used to make the film or layer. In this embodiment, the particles are first activated by any suitable method, such as crushing between plates or rollers, and then blended with the film-forming polymer 5 and then blended by any suitable method. Made into a film or layer. The method of making a film with controlled permeability is less desirable for crushing the particles after the film is manufactured because the crushing of particles on the outside of the film usually causes the particles to disintegrate. In other words, the particles are simply broken down into smaller, non-porous particles, such as fragments and the like, along the resulting pathway. When the particles within the membrane matrix are crushed 10, the particles retain their substantial integrity, although they form the desired pathway from one surface to the other. In the example of a sphere, of course, the particles have a single surface and the path passes from one point on the surface to another point on the surface. What is important to the present invention is the particle size of the filler material relative to the intrinsic thickness of the film or layer, or relative to the intrinsic thickness of the entire multilayer structure. The 15 film or layer, after activation, achieves controlled permeability. Prior to activation, the average particle size of the filler material is less than the inherent thickness of the film, layer or multilayer structure. Advantageously the 'activation step does not change the inherent thickness of the controlled permeability layer or the controlled permeability film. The intrinsic thickness before activation is substantially the same as the film thickness or measurement after activation. 20 The average particle size of the filler material is at least two thirds of the inherent thickness of the film or layer. Preferably, the ratio of average particle size to film thickness or metering is at least 0.70, and more preferably at least 0.80. The average particle size is smaller than the inherent thickness of the film or layer, that is, the ratio of the average particle size to the thickness or meter of the film 18 826 200424241 is 0.99 or less, and preferably, the average particle size is relative to the film thickness or meter The ratio is 0.90 or less. r is preferably a filler material having a narrow particle size distribution. It was found that the narrow particle size distribution is particularly suitable for achieving consistent activation results. Particularly preferably, the average particle size of the filler material and the size of 90% of all particles meet the general and better requirements for the inherent film thickness described above. The desired particle size of the filler material depends on the inherent thickness. Example-For a single layer film, the preferred filler size range is 14 to 68 microns. 10 The particle size of the filler material can be determined by methods known in the art, such as by a particle counter (Coulter counter) method or by a microscope. The amount of filler in the film of the present invention is selected so that the film is sufficient to provide the desired controlled permeability after it has been treated by the activation step. Better than 15, the amount of filler in the layer with controlled permeability, based on the total weight of filler and film-forming polymer present in the layer, is at least 0.01 weight percentage or better It is 0.05% by weight or more, more preferably at least 0.1% by weight or more. The filling amount in the controlled permeability layer should be 15% by weight or less, preferably 10% by weight or less, more preferably 8% by weight or less, most preferably 6% by weight or less Low, particularly preferably 4 weight percent or less. A particularly preferred range of the filler amount is from 0.025 weight percent to 8 weight percent. The surface of the filler can be modified, for example, with a surface modifier to make it more hydrophobic. Surface modification can improve the dispersibility of the filler and / or its adhesion to the polymer matrix of 19 200424241. Advantageously, the filler is uniformly dispersed in the polymer matrix. Suitable reagents are known in the art and include, for example, polymers and fatty acids. Preferred surface modifiers are those approved by FdA and include, for example, calcium stearate. * 5 The composition for a film according to the present invention including a film-forming polymer and a filler material may further include additives that impart or enhance specific characteristics of the film, including but not limited to colorants, antioxidants, stability Agents, anti-fog agents, plasticizers, thickeners, weaving, flow promoters, surfactants, materials added to improve the processability of the composition, and the like. These additives _ 10 additives generally have very little (if any) effect on the permeability of the membrane produced by the activation step, because the permeability is the result of the porosity in the filler. In the case where the permeability is the main function of the solution / diffusion transport mechanism, these additives generally have a greater effect on the permeability of the membrane. The composition can be prepared by conventional blending techniques using a twin roll mill, a Banbury mixer, and single- and dual-shaft extruders. The film of the invention is particularly suitable for packaging applications, such as the packaging of freshly cut agricultural products. Preferably, the film is suitable for the packaging of food and horticultural products, most preferably the packaging of fresh agricultural products, such as fruits, vegetables, and flowers. Fresh produce can be packaged in a controlled gas environment, and the stone ratio is maintained at an optimal level of 20 packaging items to improve its shelf life, storage quality, and / or reduce or avoid malodor. The package body according to the present invention comprises the controlled permeability film of the present invention, and one or more articles, preferably at least one packaged article that benefits from a controlled penetration or modified gaseous environment . Such articles 20 200424241 include, for example, foods such as vegetables and fresh fruits and flowers or microorganisms, and items that are preferably prone to breathing or oxidation, such as cut fruits and vegetables. As used herein, the term "wrapped," and its analogous terms / thinking of one or more items is provided by the film provided with a controlled penetration according to the present invention. Articles and the barrier layer of the external environment to be enclosed or encapsulated. Preferred packages include fresh and / or pre-cut agricultural products, such as fruits, vegetables or flowers. Benefiting from agricultural products packaged with the film of the present invention, Including but not limited to carrots, green broccoli, cauliflower, cabbage, mushrooms, brussels sprouts, beans, chicory's celery, radishes, 10 spinach, asparagus, endive vegetables, okra, Jerusalem artichoke, tomatoes, vegetable blends , Yali, Pear, Plum, Perilla, Grape, Apricot, Citrus, Fragrant, Rose Peach, Kiwi, Grapefruit, Peach or Mango. The film according to the invention allows to maintain an improved gas environment within the package, which The gas environment is consistent with the requirements for agricultural products to breathe, produce ethylene and mature. The optimal gas environment 15 for each agricultural product is different. The film or package with controlled permeability of the present invention can be designed Provides a relatively high oxygen transfer rate (〇TR). This high 〇TR film is particularly suitable for packaging agricultural products with high respiration, avoiding or significantly # reducing unwanted phenomena caused by low oxygen concentrations in the package, such as corruption Alternatively, the film or package with controlled permeability of the present invention 20 can be designed as required to allow relatively low oxygen transfer effects, such as agricultural products for relatively low oxygen transfer effects, such as romaine lettuce ( Romaine lettuce) ° If appropriate, the package may contain one or more components other than film and packaged items, such as cardboard, trays, or container-like or box-like components. Β? Q 21 The package may be any A suitable form, for example, is in the form of a bag, bag, pouch or container, such as a-container, wherein the film having controlled permeability according to the present invention is a panel located on at least-side of the container. The bags provided by the invention include, for example, unfilled or filled retail · consumer-disposable-zipper or other interlocking seals, open bags, food storage bags, household storage bags , Refrigerated bags, sandwich bags, and garbage. A specific embodiment of the present invention includes a food preservation bag, which includes a film with controlled permeability according to the present invention, and a variety of foods as needed. According to the present invention Packages provided include, for example, retail_consumer_disposable bags for packaging a wide range of different items, such as meat, agricultural products, and the like, before they are sold or stored at home. The inventive package can be manufactured by methods known in the art, such as heat-sealing the periphery of the film according to the invention, or by a forming, filling and sealing device. The package can include Resealing devices, such as a zipper or "compact pouch," type device, allow consumers to repeatedly reseal the package. The film and packaging system of the present invention is suitable for retail packaging and g products service industries, such as schools, restaurants, hospitals, and similar places, where appearance, long-term storage, and safety are important factors. The present invention also provides a packaging body which is a container having controlled permeability, wherein the internal permeability of the container is controlled by using a film according to the present invention, the film being used in one of the containers. Or a multi-walled window as a breathable panel. Alternatively, the container is made of a substantially air-impermeable material. The penetrability and area of the panel can be designed to provide oxygen and dioxin i 200424241 carbon flux, which is approximately equal to the estimated respiration rate of the amount of fresh produce packaged. The application of the present invention with a controlled transmissive film is not limited to.

The packaging of agricultural products or organisms may also include other applications, including repackaging A 5 applications and non-packaged applications, such as:-Monitoring the rate of respiration, where the rate of respiration can be derived from the membrane's known permeability and accumulation of respiration gases Assays; enhances the absorption, removal, or indication of polymer additives, in which the effect of gas or liquid penetrating polymers limits the effectiveness of the additives; 10-packaging applications for fresh red meat;-establishing and constructing household bags; medicine Applications, including disposable health care towels and surgical gowns, and personal hygiene applications; packaging of one meat (except fresh red meat), poultry products, dairy products, or fish products; 15-packaging of drugs, pharmaceuticals, and microbial culture media ; The packaging of a living organ. [Peach method] φ The following examples are illustrative examples of the present invention, but should not be used in any way to explain the limitation of the scope of patent application for inventions. · The following methods are used to determine the following parameters: · · (g / cm3): ASTM D- 792; Dagger number (g / 10 minutes): ASTM 〇1238, 190〇c / 2 16 kg (Condition E); 23 200424241 Dart Impact A (gram): ASTM D-1709 (66 cm (26 inches) falling ball height); Elmendorf tear strength (Elmendorf tear strength) ( G): ASTM D-1922, Method A.

5 Tensile properties include 1% and 2% secant modulus: ASTM D-882. The tensile properties and modulus were tested on a sample of 2.54 cm x 20.3 cm (1 inch x 8 inches), and the length was measured using 10 cm (4 inch). The crosshead speed of the tensile property is 50.8 cm / min (20 inches per minute), and the crosshead speed of the modulus is 2.54 cm / minute (1 inch / 10 minutes). "MD" means mechanical direction and "CD" means cross direction. The film-forming polymers used in these examples are commercially available high-pressure LDPE (ethylene homopolymer) with a density of 0.923 g / cm3 (g / cm3) and a melting index (Id = ΐ · 9 g / 10 minutes. The filler used in these examples is non-porous oxidized stone beads, which can be purchased from potters

Industries (a division of PQ Industries, U.S.A.). Single-layer film was blown on an Egan extruder, using a 3-inch mold and a 70-mil mold gap. The maximum mesh size on the screen pack is 120 (approximately 200 microns) to prevent oxidized stone beads from accumulating before leaving the mold. The melting point is about 220 ° C. The temperature distribution of extruder 20 is 150/160/171/177/182/193/204 ° C. The inflation ratio is 2.5. For activation, the film is passed through a set of calender rolls stacked parallel to each other and running at the same speed. The temperature system was set to 23 t and the pressure system was set to 0.41 N / mm to control the degree of penetration achieved in the film. Film thickness measurement 24 200424241 unchanged during the activation step. The oxygen transfer rate of the unactivated membrane samples 1 to 3 was 900 nmol m_1 S · 1 Gpa · 1. The composition of the film samples is shown in Table 1. Sample 4 is not a sample according to the invention. 5 AI sample filler average particle size (// m) filler filling amount (Wt. ° / o) film thickness measurement (#m) ratio of particle size to film thickness measurement 1 glass particles (SPHERIGLASS) 3000, type A 35 0.025 41 0.9 2 Separated glass beads 602590 38 0.05 38 1.0 3 Separated glass beads 602590 38 0.1 38 1.0 4 SPHERIGLASS 2900, A type 42 0 69 0.6

The series of controlled permeability characteristics of the activated film is shown in Table 2. 25 200424241 Table 2

Sample oxygen transfer rate Carbon dioxide transfer rate Θ ratio [nmol / m * s * Gpa (cc * mil [nmol / m * s * Gpa (cc * mil / 100 in2 / day / atm)] / 100 in2 / day / atm)] 1 48860 (17450) 50120 (17900) 1.0 2 6440 (2300) 8960 (3200) 1.4 3 15400 (5500) 18060 (6450) 1.2 4 3360 (1200) N / MN / MN / M means "not measured ".

The series of mechanical properties of membrane samples 1-3 after activation are shown in Table 3.

26 200424241

Table 3 Sample number 1 2 3 Falling ball impact A 64 93 84 Elmendorf A, CD (g) 198 226 201 Elmendorf A, MD (g) 170 126 137 1% secant modulus, CD ( ksi / MPa) 41.5 / 286 33.3 / 230 34.7 / 239 2% secant modulus, CD (ksi / MPa) 35.7 / 246 28.6 / 197 29.6 / 204 1% secant modulus, MD (ksi / MPa) 29.9 / 207 28.3 / 195 32.4 / 223 1% secant modulus, MD (ksi / MPa) 27.3 / 188 25.8 / 178 28.3 / 195 CD tensile yield (psi / MPa) 1567 / 10.8 1735 / 12.0 1757 / 12.1 yield strain 13 14 15 Final strength (psi / MPa) 2136 / 14.7 2572 / 17.7 2284 / 15.8 Strain at break point 420 522 446 Grabability (ft * lb / cu.In / kJ / cm3) 1225 / 14.9 1576 / 19.1 1348 / 16.3 MD Tensile Yield (psi / MPa) 1766 / 12.2 1877 / 12.9 1947 / 13.4 Yield Strain 14 15 16 Final Strength (psi / MPa) 3331 / 23.0 3063 / 21.2 2741 / 18.9% Strain at Breaking Point 176 222 168 Weldability (ft * lb / cu.In / kJ / cm3) 807 / 9.8 975 / 11.8 736 / 8.9 27 200424241 Table 4 reports comparative oxygen transfer data for most different membranes that fall within the scope of the invention and that do not fall within the scope of the invention. This data demonstrates the importance of non-porous glass bead size / film thickness ratio, activation, and the presence of glass beads. Table 4 Proportion of sample bead membrane activated / unactivated OTR " 5 * 0.61 activated 500 6.1 * 0.9 activated > 7500 6.2 * 0.9 unactivated 350 7 * 1.0 activated * 2300 8 * 1.1 viable 4000 9- no beads — 800 10 *-no beads — 1080

5 * LDPE 503A (0.923 g / cc, 12 is 1.9)

^ ELITE * 5400G, (0.916 g / cc, 12 is 1.0), 1.5 mil metering ^ AFFINITY * PL 1850, (0.902 g / cc, 12 is 3.0), 0.8 mil meter main non-porous glass beads 10 * Trademark of The Dow Chemical Company [Simplified description of the drawing]: None [Representative symbol table for main components of round type] ·· No 28

Claims (1)

Scope of patent application: 1. A film with controlled penetration, comprising: A · -polymeric film 'which has an inherent thickness, and a non-porous inert filler, which is filled with The agent is blended into Guzhong and has an average particle size such that the ratio of the average particle size to the film thickness of the filler is from 0.67 to 0.99. 2. A film with controlled permeability comprising: A. A polymerizable film having an inherent thickness and B • a non-porous, inert particulate filler which is blended into The film also has an average particle size such that the ratio of the average particle size to the film thickness of the filler is 067 to 0099. The particle filler is subjected to a compressive force treatment, resulting in at least a portion of the particle filler. Obstructed. 3. A film with controlled permeability, comprising: A. a polymerizable film having an inherent thickness, and B. a non-porous, inert particulate filler which is blended into the The film also has an average particle size such that the ratio of the average particle size of the filler to the film thickness is 0.67 to 0.99. The film is subjected to a compressive force treatment, causing at least a portion of the particle filler to be broken. 4. A compressed, controlled permeability film comprising: A. a polymerizable film with an inherent thickness, and B. a non-porous, inert particulate filler, the filler is doped with Is incorporated into the film and has an average particle size such that the average 5._ particle size to film thickness ratio of the filler is from 0.67 to 0099, and at least a portion of the particle filler is crushed. A method for manufacturing a controlled penetrability method, the method comprising the following steps: A. Blending a film-forming polymer with an inert, non-porous particulate filler, the particulate filler having an average particle Dimensions; Β. Form a film with inherent film thickness from the blend of (A), so that the average particle size of the filler for the rotation is 0.67 to 10 C. 〇99; and (B) of The film is compressed and the filler is crushed. So that at least a part of the particles 6. A method of making a controlled penetrability, the method described in the following steps: [15] Blend a film-forming polymer with an inert, non-porous, dish-crushed particle filler In combination, the particle filler has an average particle size; B • A film having an inherent film thickness is formed from the blend of (A), so that the ratio of the average particle size of the filler to the film thickness is 0.67 to 0.99. 20 The film according to item 1 of the patent application range, wherein the content of the filler is from 0.01 to 15 weight percent of the filler. 9. The film of item 1 of the + month patent, which has an S ratio of 0.5 to 2.5. ⑺No. Of patent scope! Item of a film comprising a polyolefin polymer. . As in the patent scope please! The film of the item has an intrinsic thickness of micrometers. • The film as claimed in item 1 of the patent scope, which has a -single layer structure. 30 200424241 12. The film according to item 1 of the patent application has a multilayer structure in which the filler is incorporated into a single layer. 13. The film of claim 1 has a multilayer structure in which a filler is incorporated into at least two layers. 5 14. The film of claim 1, wherein the filler has an average particle size of 30 to 70 microns. 15. The film as claimed in claim 1, wherein the filler is a spherical microcrystalline inorganic substance. 16. The film according to item 1 of the patent application, wherein the filler is a silicon-containing material. 10 17. The film according to item 1 of the scope of patent application, which is in the form of a bag or a pouch. 18. A package comprising a controlled permeability film as described in item 1 of the scope of the patent application. 19. A method for improving the shelf life of a perishable item, comprising packaging the 15 item with a controlled permeability film as described in item 1 of the scope of the patent application. 20. The film according to item 1 of the patent application range, wherein the filler content is 0.01 to 5 weight percent of the film. 21. The film according to item 1 of the patent application range, wherein the filler content is 0.01 to 2 weight percent of the film. 31 200424241 柒 Designated representative map: (1) Designated representative map of this case is: (II) Brief description of the representative symbols of the components in this case: (none) 捌 If there is a chemical formula in this case, please disclose the chemical formula that best shows the characteristics of the invention :