JP2015124166A - Styrene foam structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a styrene foam structure that imparts a high antibacterial function to the surface of a foamed polystyrene bead constituting styrene foam at low cost.SOLUTION: The styrene foam structure of this invention is a styrene foam structure comprising bead method-based styrene foam, wherein silver zeolite 20 scatters over the whole surface of a polystyrene bead 11.

Description

  The present invention relates to a foamed polystyrene structure, and more particularly to a foamed polystyrene structure comprising a polystyrene foamed bead method.

  Styrofoam is a material obtained by foaming and curing polystyrene with fine bubbles. Lightweight, excellent in heat insulation, extremely easy to mold and cut, inexpensive, elastic, and excellent in shock absorption. Used to insulate objects that need to be kept warm. And it is often used as a container taking advantage of its light weight, thermal insulation and shock absorption.

  Moreover, it is used not only as a container but also as a container for cultivation of vegetables or the like, or as a hydroponic cultivation panel (for example, Patent Document 1) by utilizing the property of floating in water.

JP 2009-171944 A JP 2012-165680 A

  At present, containers made of styrene foam are used in large quantities as containers for transporting seafood and containers for vegetables, but in recent years, it has been required to add various functions to containers for transport. In particular, there is a great demand for containers having antibacterial functions so that they can be stored for a long period of time, but even if an antibacterial agent is to be coated on the surface of a polystyrene foam container, the coating is uniformly and highly concentrated and the coating is maintained for a long period of time. It is difficult.

  Also, in hydroponics panels, once used, plant roots remain inside the panel body (fine gaps between the styrofoam beads), and the plant roots can also be removed by washing the surface of the panel body. Difficult to do. Further, if the plant roots remaining inside the panel main body are left unattended, when the planted plant is infected with a disease, pathogenic bacteria remain inside the remaining roots, which may cause secondary infection. Moreover, if the plant roots rot inside the panel body, there is a risk of becoming a hotbed of pathogenic bacteria, which is not preferable.

  From such a background, when the panel main body is repeatedly used, not only the panel main body from which the planted body has been removed is carefully washed but also a treatment such as careful sterilization by heating or the like is required. However, repeated washing and heating of the panel body made of expanded polystyrene makes the panel body severely damaged, and the foamed resin beads may be thirdarily foamed by heating, so that the number of reuses is limited.

  In particular, the occurrence of diseases caused by the use of polystyrene foam in the panel body is a problem in the cultivation of sprout such as radish, cultivated radish, tomatoes, cucumbers, melons, honeybees, leeks, garlic, lettuce and spinach. In these cultivations, there is a demand for techniques relating to the prevention of invasion of plant roots into the interior and antibacterialization of the interior of the panel body of the polystyrene foam panel body used.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a foamed polystyrene structure having a large antibacterial function on the surface of foamed polystyrene beads constituting the foamed polystyrene at a low cost. is there.

  The expanded polystyrene structure of the present invention is an expanded polystyrene structure made of bead-method expanded polystyrene, and has a configuration in which silver zeolite is scattered on the entire surface of polystyrene beads. In such a configuration, the silver zeolite exists on the surface where two adjacent polystyrene beads are fused, and the surface of each polystyrene bead is also in a minute gap between the plurality of polystyrene beads. Since silver zeolite is present in the surface, pathogenic bacteria can be killed by the antibacterial action of silver on the surface of the expanded polystyrene structure and in the minute gaps. Moreover, since plant roots also dislike silver, plant roots can be prevented from entering minute gaps between a plurality of polystyrene beads.

  The silver zeolite is preferably contained in an amount of 0.15% by mass or more and 0.5% by mass or less based on the expanded polystyrene. And it is preferable that the silver content rate in a silver zeolite is 5 to 20 mass%.

  The average particle diameter of the silver zeolite is preferably 1 μm or more and 100 μm or less.

  The silver zeolite is present on the fused surfaces of the two polystyrene beads fused together.

  In the polystyrene foam structure of the present invention, silver zeolite is present in the minute gaps between the surface and the polystyrene beads, and the antibacterial action can be exerted on the entire structure for a long period of time.

It is typical sectional drawing of the foamed styrene bead of the raw material which concerns on embodiment. It is a typical expanded sectional view of the polystyrene foam structure concerning an embodiment. It is a typical expanded sectional view of the polystyrene foam structure concerning a comparison form.

  Before explaining the embodiments of the present invention, the background to the present invention will be described below.

  In Patent Document 2, in the antibacterial hydroponics panel, by filling a gap between a plurality of foamed resin beads with a resin in which an inorganic substance having antibacterial properties is mixed, the intrusion of plant roots into the panel body and the panel body are prevented. A technique for antibacterial treatment inside is disclosed. However, in the technology disclosed in Patent Document 2, the emulsion resin mixed with silver zeolite is impregnated under reduced pressure in the gap between the foamed resin beads constituting the panel and dried to produce the panel. However, since the production cost is increased and the silver zeolite is mixed with the emulsion resin, the amount of the silver zeolite put into the gap is limited, and a sufficient antibacterial function cannot be obtained.

  In view of the above points, the present inventors have made various studies to obtain a foamed polystyrene structure having a large antibacterial function at low cost, and have come up with the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity.

(Embodiment 1)
In the expanded polystyrene structure, a polystyrene raw material bead impregnated with a foaming agent is usually pre-foamed (primary foaming) to prepare a pre-foamed bead first, and the pre-foamed bead is placed in a mold using steam. Secondary foaming and welding to each other form a desired shape according to the mold.

  In the first embodiment, as shown in FIG. 1, pre-expanded beads 10 having a large number of finely powdered silver zeolite 20 attached to the surface are used, and this is put into a desired mold and secondarily expanded using steam and welded together. Let As shown in FIG. 2, the foamed polystyrene structure thus prepared is dotted with powdered silver zeolite 20 over the entire surface of the polystyrene beads 11 that have been secondarily expanded. That is, the silver zeolite 20 is scattered in the minute gaps between the polystyrene beads 11, is also scattered on the fused surface between the polystyrene beads 11, and the surface of the expanded polystyrene structure. It is also scattered on the exposed outer surface of the polystyrene beads 11. In the secondary foaming process, the upper surface of the silver zeolite 20 on the surface of the expanded polystyrene structure is exposed, and the remaining portion is embedded and fused in the expanded polystyrene structure to be firmly fixed.

  The silver zeolite 20 is a substance that is an inorganic antibacterial agent in which silver ions having antibacterial properties are supported on a zeolite having a three-dimensional skeleton structure.

  As a comparative form, a cross-sectional schematic view of a normal expanded polystyrene structure without silver zeolite 20 is shown in FIG. The foamed polystyrene structure of the comparative form has no antibacterial function because only polystyrene exists on the surface and the surface of the gap between the foamed polystyrene beads. Therefore, for example, in the case of a styrofoam structure such as a seafood trolley box or hydroponics panel, if bacteria adhere to the surface or gaps, it propagates and hinders preservation of seafood and plant cultivation for a long time. Will occur.

  On the other hand, in the expanded polystyrene structure of the present embodiment, since a large number of silver zeolite 20 exists on the surface and gaps, even if bacteria adhere to the surface and gaps of the expanded polystyrene structure, they are sterilized by silver ions and propagate the bacteria. Is reliably deterred.

  The toro box and hydroponics panel that are the polystyrene foam structure of the present embodiment not only have the effect of preventing the growth of fungi during storage of fishery products and agricultural products and hydroponics, but also when they are reused -It can be reused many times by simple sterilization. In particular, hydroponics panels can reduce the number of times of mechanical cleaning of the surface, no thermal treatment is required, reuse processing is simple and low cost, and the number of reuse can be dramatically increased. Become.

  The expanded polystyrene structure of the present embodiment is formed by attaching a large number of fine particles of silver zeolite 20 to the surface of the pre-expanded beads 10 and secondary-expanding the pre-expanded beads 10 to which the silver zeolite 20 has adhered in a mold. In order to attach the fine particles of the silver zeolite 20 to the surface of the pre-expanded beads 10, for example, the fine particles of the pre-expanded beads 10 and the silver zeolite 20 are put in a container and mixed with an organic solvent such as alcohol or water as necessary. The process of doing is performed. When an organic solvent such as alcohol or water is added, it is removed by drying. In order to firmly attach the fine particles of the silver zeolite 20 to the surface of the pre-expanded beads 10, the fine particles of the silver zeolite 20 are controlled by appropriately controlling the conditions such as the organic solvent, water and the temperature and time. 10 is preferably in a state of biting.

  The average particle diameter of the silver zeolite 20 mixed at this time is preferably 1 μm or more and 100 μm or less. Even if it is less than 1 μm or more than 100 μm, the silver zeolite 20 is difficult to adhere to the surface of the pre-expanded bead 10, or even once attached, it will be peeled off, and a sufficient amount is deposited on the surface of the pre-expanded bead 10. This is because there is a great possibility that it will be difficult to adhere. The average particle size of the silver zeolite 20 may be obtained by measuring by a known method. For example, the average particle size = 6 / (specific gravity × specific surface area) using the specific surface area value per 1 g of powder by a powder specific surface area measuring device. It can obtain | require from the calculating formula x10000 [micrometer]. The average particle size is preferably 50 μm or less because it can be more reliably attached to the surface of the pre-expanded beads 10.

  The silver zeolite 20 is preferably added so as to be contained in an amount of 0.15% by mass or more and 0.5% by mass or less based on the expanded polystyrene. If it is less than 0.15% by mass, it may be difficult to exert desired antibacterial performance. If it exceeds 0.5 mass%, it tends to be difficult to keep it on the surface of the pre-expanded beads 10, which may increase the cost.

  The silver content in the silver zeolite is preferably 5% by mass or more and 20% by mass or less. If it is less than 5% by mass, the antibacterial function in the expanded polystyrene structure may be insufficient, and if it is more than 20% by mass, such a silver zeolite is expensive and may be expensive.

  The hydroponics panel which is the polystyrene foam structure of this embodiment not only suppresses that a pathogenic microbe propagates on the surface and the clearance gap between polystyrene beads by silver zeolite 20, but also suppresses adhesion of algae to the surface. In addition, it is possible to prevent the roots of the plant from entering the minute gaps inside the panel and to have no influence on the plant to be cultivated. And the process for reusing can be performed easily and the number of times of reusing can be greatly increased.

  The container of fishery products and agricultural products, which are the polystyrene foam structure of the present embodiment, can only be preserved for a long period of time by suppressing the propagation of pathogenic bacteria on the surface or in the gaps between polystyrene beads by the silver zeolite 20. In addition, since the antibacterial action is maintained for a long time, the container can be used repeatedly many times if it is cleaned and simply sterilized.

(Other embodiments)
The above-described embodiment is an exemplification of the present invention, and the present invention is not limited to these examples, and these examples may be combined or partially replaced with known techniques, common techniques, and known techniques. Also, modified inventions easily conceived by those skilled in the art are included in the present invention.

  The foamed polystyrene structure may have any shape. The size and the degree of foaming of the polystyrene beads are not limited, and various additives (for example, colorants) may be added.

  Styrofoam structures are not limited to seafood and agricultural containers, and hydroponics panels, but any application that uses silver zeolite functions such as antibacterial and adsorptive properties such as food trays and indoor insulation materials It may be anything.

  The method for attaching silver zeolite to the polystyrene bead surface is not particularly limited. It may be adhered by coating, or silver zeolite may be mixed with the pre-expanded beads 10 in the mold in the secondary foaming.

  Copper, besides silver, has a high antibacterial action, so copper zeolite may be used. Silver-copper zeolite may be used. Alternatively, silver zeolite and copper zeolite may be mixed and used, or other functional fine particles (for example, scent sustained-release fine particles) may be mixed and used.

  Moreover, you may utilize the adsorption function of a zeolite. For example, a deodorizing function may be added, or a function of adsorbing ethylene to maintain the freshness of fruits and the like may be added.

  As described above, the expanded polystyrene structure according to the present invention has an antibacterial function and is useful as a hydroponics panel, a container for marine products and agricultural products, and the like.

10 Pre-expanded beads 11 Polystyrene beads 20 Silver zeolite

Claims (5)

A foamed polystyrene structure comprising a polystyrene foamed bead method,
A polystyrene foam structure in which silver zeolite is scattered on the entire surface of polystyrene beads.   2. The expanded polystyrene structure according to claim 1, wherein the silver zeolite is contained in an amount of 0.15 mass% to 0.5 mass% with respect to the expanded polystyrene.   The expanded polystyrene structure according to claim 2, wherein the silver content in the silver zeolite is 5% by mass or more and 20% by mass or less.   The expanded polystyrene structure according to any one of claims 1 to 3, wherein the silver zeolite has an average particle size of 1 µm or more and 100 µm or less.   The expanded polystyrene structure as described in any one of Claim 1 to 4 with which the said silver zeolite exists in the fusion | melting surface of the two said polystyrene beads adhering adjacently.

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