Patent Application
20080095959
In describing the preferred embodiments of the present invention, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and is to be understood that each specific term includes all technical equivalence which operate in a similar manner to accomplish a similar purpose.
According to one aspect, the present invention is directed to a material for use in beverage infusion packages. The material in accordance with one embodiment includes at least one cellulosic fiber woven together with at least one heat-bondable synthetic fiber. In the material, preferably, a plurality of cellulosic fibers are woven together with at least one heat-bondable synthetic fiber. The fibers are typically elongated and may be arranged in the woven portion as either weft or warp fibers, or both. In the particular embodiment shown in
In general, the fibers for use in the present invention may be any thickness so long as they are weavable and strong enough to withstand the infusion process (e.g., being immersed in a heated liquid for at least the requisite amount of time for infusing the liquid with the infusion substance without disintegrating). A suitable cellulosic fiber is about 32 denier. A suitable heat-bondable synthetic fiber is about 26 denier. The cellulosic fibers may be any fiber made from any plant, cellulose or derivative of cellulose. A preferred cellulosic fiber is bamboo. Bamboo transfers moisture well and has been found to suitable for use with biodegradable synthetic fibers, such as polylactic acid. Other suitable fibers include but are not limited to cotton, linen, flax, ramie, silk, abaca and viscose.
The heat-bondable synthetic fibers may be any synthetic fiber capable of being bonded to another heat-bondable synthetic fiber and/or the cellulosic fibers through application of heat, such as through heat-pressing. Without limitation, suitable heat-bondable synthetic fibers include heat-bondable polymers, thermoplastics and resins, such as heat-bondable polyolefins, polyesters, polyamides, polyhydroxyalkanoates and polysaccharides. Some specific heat-bondable synthetic fibers include: polypropylene, polyethylene, ethylene acrylic acid and ethylene vinyl acetate. Preferably heat-bondable synthetic fibers having a bonding temperature above one hundred degrees Centigrade is desirable.
Preferably, the heat-bondable synthetic fibers are biodegradable, but not required. Such fibers are those fibers that are heat-bondable, but are capable of being broken down by living things (especially, microorganisms), such as bacteria and fungi, under natural conditions. Suitable heat-bondable biodegradable synthetic fibers for use in the infusion package of the present invention include fibers made from biodegradable thermoplastics or thermopolymers, such as biodegradable aliphatic polyester polymers. Such biodegradable aliphatic polyester polymers include: polyhydroxy butyrate (PHP), polyhydroxy butyrate-co-valerate (PHBV), polycaprolactane, polybutylene succinate, polybutylene succinate-co-adipate, polyglycolic acid (PGA), polylactide or polylactic acid, polybutylene oxalate, polyethylene adipate, polyparadioxanone, polymorpholineviones, and polydioxipane-2-one.
A particularly preferred heat-bondable biodegradable synthetic fiber is polylactic acid or polylactide. Polylactic acid and polylactides are commonly referred to as PLAs. PLAs are commercially available from Yamanaka Industry Co. Ltd. under several trade names including Tearoad Soilon®. PLAs are also described in U.S. Pat. No. 5,338,822 (Gruber et al.); U.S. Pat. No. 6,111,060 (Gruber et al.); U.S. Pat. No. 5,556,895 to (Lipinsky et al.); U.S. Pat. No. 5,801,223 (Lipinsky et al.); U.S. Pat. No. 6,353,086 (Kolstad et al.); and U.S. Pat. No. 6,506,873 (Ryan et al.), each of which hereby incorporated by reference in its entirety.
Any known process for weaving fibers may be employed in the process for producing layers of the material. For example, as shown in
The weave pattern may be tailored to produce a specified porosity, from a tightly woven layer (with decreased porosity) to a loosely woven layer (with increased porosity). However, the weave pattern must not be so solid as to prevent the infusion of an infusion substance held in an infusion package comprising the layer and not so loose as to release more than a minor amount of the infusion substance out of the infusion package.
The weave pattern may also be tailored and/or specific fibers (i.e., colorless or near-colorless fibers) may be chosen so that the layer is transparent, in that the woven fibers allow light to pass through them so that the infusion substance may be partially or fully visible through the woven fibers.
The fibers may also be treated (e.g., color-treated) and woven together in a selected weave pattern so that the woven layer demonstrates a visible and/or textured effect, such as an emblem, letter(s), word(s), logo, symbol or design.
According to another aspect, the present invention is also directed to an infusion package comprised of the material of the present invention. As shown in
Although the infusion package has been described as constituting generally two or more separate layers of material, it is contemplated that the two layers can be formed from a single layer. In this regard, a single layer can be folded over itself and heat sealed as thus far described to form the resulting two layers of the infusion package to define the compartment. In this regard, the layer of material will include cellulosic fibers woven together in any combination with at least one heat-bondable synthetic fiber arranged in the bond area of the infusion package. The sealed compartment 5 is defined by the sealed portion 6 of the infusion package. Although shown as substantially square in
As thus far described, the layers 3,4 may be made by weaving various combinations of cellulosic fibers together in any combination with at least one heat-bondable synthetic fiber in the area to be bonded. For example, both layers may be combinations of cellulosic and one or more heat-bondable fibers. Further, one layer may be the combination of cellulosic and at least one heat-bondable fiber, and the other layer either cellulosic fibers or heat-bondable fibers. Accordingly, only one layer is required to contain a heat-bondable fiber in the bond region. In the embodiment as shown in
Although
The infusion package of the present invention may also include a device for facilitating placement and/or removal of the infusion package into a container with the liquid to be infused. One known such device is a tag or tab connected to a string, in which the string is attached to the infusion package. The string may be attached to the infusion package by being stitched into one or more layers of the infusion package. If the string is made of a material capable of being heat-bonded to the layers, it also may be attached to the infusion package by heat-bonding or fusing it to one or more layers of the infusion package. Alternatively, the string may be made from the sealed layers themselves, from the heat-pressed portions of the infusion package. In this form, the string is cut out of the heat-sealed portions, such that the string is connected to the infusion package, but contains a free end. Then, a tag or tab is attached to the free end of the cut out-string. In another form, both the string and tag are cut out of the heat-sealed portions. The cut-out strings and tags for use in the infusion package may be in any form so long as the layers remain sealed such that any compartments remain intact.
The infusion substances for use with the present invention may be any known substance for infusion. Typically, such infusion substances are for infusing liquids, such as water, to impart flavors or chemical substances, such as medicinal compounds, into the liquid. Suitable infusion substances for use with the infusion package of the present invention, include tea leaves, coffee grounds, medicinal herbs and drinking powders (e.g., cocoa powder).
In accordance with another aspect, the present invention is also directed to a method of producing an infusion package.
In the method, at least one layer including the material of the present invention is provided, along with at least one infusion substance. Then, the layer or layers of cellulosic fiber woven with at least one heat-bondable synthetic fiber may be combined with each other or with one or more additional layers to form the least one compartment of the infusion package. The one or more compartments are defined by one or more combined portions of the combined layers, and contain the one or more infusion substances.
In a preferred embodiment, the sealing of the layers is performed through heat-sealing. The heat-sealing of the layers together may be through any method of applying heat sufficient to bond the layers together so that they will not come apart during the infusion process (e.g., when immersed in heated water for the requisite time for infusing the water with the infusion substance). Sealing methods may include pressing, ultrasonic welding, and radio frequency welding. One particularly preferable heat-sealing method is heat-pressing.
The layers, separately or together, may be pre-cut into desired shapes for the infusion package prior to the sealing step. Alternatively, the sealed layers may be cut into the desired shape after the layers are sealed together.
Additionally, concurrently with or after the sealing step, the present method may include the step of attaching a string with a tab or tag to the infusion package. The attachment may be through stitching the string into one or more layers of the infusion package, or if the string is capable of being heat-bonded to any layer of the infusion package, the attachment may be through heat-bonding the string to the one or more layers of the infusion package.
Alternatively, after the layers are sealed, a string with or without a tab or tag may be cut out of the combined portions in a manner that leaves the string or string with tab or tag connected to the infusion package. If the cut-out string does not include a tag or tab, a tag or tab may be attached to the free end of the string after cutting out the string.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.
