| Encapsulated active particles and methods for making and using the same -> Monitor Keywords |
|
|
 
Encapsulated active particles and methods for making and using the sameRelated Patent Categories: Stock Material Or Miscellaneous Articles, Coated Or Structually Defined Flake, Particle, Cell, Strand, Strand Portion, Rod, Filament, Macroscopic Fiber Or Mass Thereof, Particulate Matter (e.g., Sphere, Flake, Etc.), CoatedEncapsulated active particles and methods for making and using the same description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20060008646, Encapsulated active particles and methods for making and using the same. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO A RELATED PATENT APPLICATION [0001] This application claims the benefit of U.S. Provisional Application No. 60/388,678, filed Jun. 12, 2002, the disclosure of which is hereby incorporated by reference in its entirety. TECHNICAL FIELD OF THE INVENTION [0002] The invention relates to preserving the properties of active particles. In particular, the invention relates to a method for encapsulating at least a portion of the active particles with a removable protective substance. BACKGROUND OF THE INVENTION [0003] It is well known that certain particles can be used to add performance properties to materials in different forms such as gases, liquids, and solids. These particles can have properties that are suitable for odor adsorption, moisture management, ultraviolet light protection, chemical protection, bio-hazard protection, fire retardance, antibacterial protection, antiviral protection, antifungal protection, antimicrobial protection, and other factors, and combinations thereof. [0004] These particles can provide such properties because they are "active". Active particles are active because they have the capacity to adsorb or trap substances, including substances that may themselves be a solid, liquid, and/or gas, for example, pollen, water, butane, and ambient air. Active particles have an adsorptive property because each particle has a multitude of pores (e.g., pores on the order of thousands, tens of thousand, or hundreds of thousands per particle). It is these pores that provide the active particle with its capacity to adsorb. For example, an active particle such as activated carbon can adsorb a substance (e.g., butane) by trapping the substance in the pores of the activated carbon. [0005] Exposing the active particles to a substance can prematurely deactivate the active particles by blocking or inhibiting the pores, thus reducing the adsorptive capacity of the active particles. That is, once the pores are blocked or inhibited with a substance, those blocked or inhibited pores may be prevented from further adsorption. However, the adsorptive capacity of active particles can be increased or restored by removing the substance that is blocking or inhibiting the pores. Hence, active particles can be rejuvenated (e.g., reactivated). [0006] A common problem often associated with active particles is that they can be prematurely deactivated. When active particles are premature deactivated, the particles cannot adsorb substances originally intended to be adsorbed, but instead, adsorbed some undesired substance. Some substances that are prematurely adsorbed may be deleterious substances. Deleterious substances are substances that cannot be easily removed from an active particle and therefore reduce the active particle's capacity for further adsorption. For example, a deleterious substance such as a molten polymer may permanently deactivate active particle. A molten polymer, for example, cannot be removed without damaging the active particle or the substance surrounding the active particle. [0007] Other substances that are prematurely adsorbed may be relatively easy to remove. That is, these types of substances can be removed using known methods of rejuvenation or reactivation that do not damage the active particles or the surrounding substance. For example, when a non-deleterious substance such as methane is adsorbed, it may be removed from the active particle by heating the particle. [0008] Advances in producing materials with active particles contained therein have been limited by adverse conditions encountered when making such materials. One such process includes, for example, an extrusion process that is used to produce strands of synthetic yarn. In an extrusion process, the process typically begins by converting a base material, such as a polymer, into a molten mixture. Then, using the molten mixture, a desired material (e.g., yarn) is extruded through an extrusion apparatus. However, when the active particle is mixed into a molten mixture, the molten mixture can deactivate the active particle by filling the particle's pores, thus inhibiting the active particle's ability to adsorb. [0009] Various extrusion approaches have been attempted to prevent active particle deactivation, but all have produced results that are ineffective or substantially weaken the base material. One approach, using activated carbon, has yielded a material having about 4% of the activated carbon by weight embedded therein as active. However, this approach required a heavy loading of activated carbon in order to produce a yarn that has at best only 4% activity out of all the carbon embedded within the yarn. A drawback of having to heavily load yarn with activated carbon or other active particle is that it results in a yarn that possesses the physical characteristics of the activated carbon (or particle) rather than the physical characteristics of the base material used to produce the yarn. Thus, a yarn or fabric created using this method has a hand and feel dominated by the carbon (or particle) additive and not the base material. Moreover, as the carbon (or particle) loading increases, the tensile strength of the base material decreases, resulting in a brittle, and non-stretching fabric. [0010] In view of the foregoing, it is an object of the invention to preserve active particles with a removable protective substance. [0011] It is also object of the invention to remove the removable protective substance to rejuvenate or reactivate the active particles, when desirable. [0012] It is another object of the invention to provide an active particle that is deactivated with a removable encapsulant for protection against premature deactivation. SUMMARY OF THE INVENTION [0013] The objects of the invention are accomplished by deactivating active particles with a removable substance (e.g., encapsulant) for protection against premature deactivation. The removable substance, as used on or with the active particles, deactivates the active particles by blocking or inhibiting the pores of the active particles. While the removable substance may have negated or reduced the adsorptive capacity of the active particles, this loss of adsorptive capacity is not permanent. Thus, when the removable substance is removed from the active particles, the adsorptive capacity increases or is restored. In other words, removal of the removable substance results in a reactivation or a rejuvenation of the active particles. [0014] One advantage of deactivating the active particles with the removable substance is that it can prevent the active particles from prematurely adsorbing a substance. If the active particles prematurely adsorb a substance (e.g., a deleterious substance) or are otherwise exposed to an adverse condition affecting adsorption, the particles can deactivate before having an opportunity to adsorb desirable substances. Premature deactivation can include deactivation on account of absorption occurring at an undesirably early time whether or not the absorbed substance was deleterious, non-deleterious or even the intended target. For example, assume that active particles are introduced for the purpose of adsorbing substance "A", but before the active particles can be used for that purpose, the active particles prematurely deactivate by adsorbing substance "B," which is not easily removeable. Had the active particles been deactivated with the removable substance, the active particles may not have prematurely adsorbed substance "B". [0015] When the removable substance is applied to the active particle, it encapsulates at least a portion of the active particle. Thus, an encapsulated particle is an active particle existing in a deactivated state, and has been at least partially filled with, covered by, or enclosed by the removable substance, but can be rejuvenated or reactivated upon removal of the protective substance. [0016] Another advantage of the invention is that the removable substance can be removed at a predetermined or otherwise desirable time after being applied to the active particles. For example, the removable substance may be removed if it is known that the substance or substances that can cause premature deactivation are not present. In another example, the removable substance can be applied to the active particles indefinitely, or for as long as the removable substance can be practically applied to the active particles. [0017] The removable substance may remain applied to the active particles until one or more predetermined conditions or substances are applied to remove the removable substance. For example, the removable substance may be removed if it is subjected to hot water and then dried. In another example, application of heat or light may remove the removable substance. The removable substance may not be displaced by another substance without outside influence unless that other substance first removes, or is specifically configured to remove, the removable substance. [0018] The removable substance enables the encapsulated particles to be subject to substances that can cause premature deactivation. For example, the encapsulated particles may be used in a process that introduces or incorporates the particles into an embedding substance. An embedding substance can be a substance that takes the form of a solid, liquid, gas, or a combination of different phases. If a deleterious substance is used in that process, the encapsulated particles are protected from being prematurely deactivated. [0019] After the encapsulated particles are incorporated into the embedding substance, at least a portion of the removable substance can be removed to reactivate the active particles. Once the removable substance is removed, the active particles can bestow performance enhancing characteristics (e.g., odor adsorption, moisture management, etc.) to the embedding substance or material. In addition to the performance enhancing characteristics that are imparted to the embedding substance, the active particles can be incorporated in a way that maintains the hand and feel, texture, durability, strength, strechability, viscosity, compressibilty, expandability, relative density, and other physical and chemical properties generally associated with the embedding substance before having the active particles incorporated therein. BRIEF DESCRIPTION OF THE DRAWINGS Continue reading about Encapsulated active particles and methods for making and using the same... Full patent description for Encapsulated active particles and methods for making and using the same Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Encapsulated active particles and methods for making and using the same patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Encapsulated active particles and methods for making and using the same or other areas of interest. ### Previous Patent Application: Fabrics of mixed-polyester-ratio bi-component fibers Next Patent Application: Magnetic powder, method for producing the same and magnetic recording medium comprising the same Industry Class: Stock material or miscellaneous articles ### FreshPatents.com Support Thank you for viewing the Encapsulated active particles and methods for making and using the same patent info. IP-related news and info Results in 0.17805 seconds Other interesting Feshpatents.com categories: Software: Finance , AI , Databases , Development , Document , Navigation , Error 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
