JPH1135064A - Separate sheet for container stacking - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a separate sheet which is inexpensive and prevents dust or miscellaneous germs from attaching. SOLUTION: This separate sheet 10 which is inserted between containers 14 in stacking a plurality of them is made of polyethylene glycol and polyamide added ABS resin. In this case, it is preferable that the same, in addition, has soluble glass containing silver ion. Also it is preferable that the separate sheet is made as a multilayer body, and polyethylene glycol and polyamide are added to its surface layer. In this case also, it is preferable that the surface layer has still more soluble glass containing silver ion. By this, practically with no cost increase, the separate sheet can exhibit antistatic characteristics with little attachment of dust, etc., and can keep the container clean. Furthermore, as the sheet can be washed for reuse, the same has a longer life and thus is good in point of the conservation of resources.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separate sheet interposed between food and drink containers such as glass bottles when the food and drink containers are stacked.

[0002]

2. Description of the Related Art Water, juice, soft drinks and the like are filled in various food and drink containers such as glass bottles, plastic bottles and cans. Such containers for eating and drinking, before the filling of the contents liquid, that is, in the distribution process from a glass processing plant, a resin molding plant, a canning factory, etc. to a filling plant of the contents liquid, a plurality of eating and drinking containers on the pallet. Arranging and stacking containers is performed. In order to stack food and drink containers, it is not possible to load other food and drink containers directly on the food and drink container,
A plate-like separate sheet is interposed between each row of such stacked eating and drinking containers. As the separate sheet, a flat plate made of paper such as cardboard has been used for reasons such as low cost and light weight.

[0003]

In the state where food and drink containers are stacked using separate sheets, the separate sheet comes into contact with the mouth of each food and drink container. Therefore, if the separate sheet is dirty, there is no possibility that trash, various germs, and the like are mixed in the food and drink container from the separate sheet. Because of the necessity of maintaining cleanliness, separate sheets are discarded once used, and new ones are always used. However, even if it is a new one, there is no denying that garbage, various germs and the like may adhere to the container between the time it is manufactured and the time it is used or when it is interposed between eating and drinking containers. In particular, if the separate sheet is charged with static electricity, it attracts dust and easily adheres. In addition, being disposable is a barrier to further cost reduction and is undesirable from the viewpoint of resource protection. Therefore, it is conceivable to apply an antibacterial agent to such a paper separate sheet. However, the addition of the antibacterial agent application step greatly increases the production cost. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a low-cost separate sheet that prevents attachment of dust and germs.

[0004]

According to the present invention, there is provided a separate sheet interposed between a plurality of food and drink containers when they are stacked, comprising a acrylonitrile-butadiene-styrene resin to which polyethylene glycol and polyamide are added. It is characterized by the following. At this time, it is desirable to further have a melting glass containing silver ions. In addition, the separate sheet is made into a multilayer body,
It is preferable that polyethylene glycol and polyamide are added to the surface layer. Also in this case, it is desirable that the surface layer further has a soluble glass containing silver ions.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, a separate sheet according to the present invention is used when food and drink containers 14 such as glass bottles, plastic bottles and cans are stacked.
Used with intervening. Separate sheet 10
It is a flat plate-like body having a size substantially equal to that of the pallet 12 and 1100 × 1300 mm. The plate thickness is preferably larger as the rigidity increases, but from the viewpoint of weight reduction and cost, a plate thickness of 0.5 to 4 mm is preferable. The separate sheet of the present invention is made of acrylonitrile-
Butadiene-styrene resin (hereinafter referred to as ABS)
It is characterized by consisting of. This is because if it is made of metal, it is too heavy, and if it is made of another resin, various properties such as smoothness described later are not desirable.

The present invention is characterized in that a specific antistatic agent, that is, a hydrophilic polymer of polyethylene glycol and polyamide is added to the ABS resin. In the case of a conventional separate sheet made of plastic, it is sometimes charged by static electricity due to friction or the like, and dust is likely to adhere. However, in the present invention,
When the ABS plate has the antistatic agent composed of the above components, charging is effectively prevented, and adhesion of dust and the like is suppressed. A general antistatic agent utilizes a surfactant, but its effect is reduced by wiping the surface with a cloth or washing with water. Therefore, it cannot be washed in order to maintain the antistatic effect, which is not desirable for hygiene or reuse. However, when the antistatic agent composed of polyethylene glycol and polyamide in the present invention, the effect of washing and the like is less reduced, the antistatic effect is permanently maintained, and can be used for washing and the like, which is desirable for hygiene management. Further, it can be reused with high quality, and the life can be extended. The amount of polyamide added is A
10-20% by weight, based on BS, is preferred and about 15% by weight is optimal. If the amount is less than 10% by weight, the antistatic effect is small, and if it is more than 20% by weight, the characteristics of the ABS are impaired. The amount of polyethylene glycol added depends on the copolymerization ratio of ABS, but is preferably 0.1 to 3% by weight, and most preferably about 1% by weight. If the amount is less than 0.1% by weight, the effect is small. If the amount is more than 3% by weight, the surface becomes sticky. In addition, a dispersant such as calcium stearate is generally added to a resin composition such as ABS. However, such a dispersant can be made unnecessary by adding polyethylene glycol. Further, in addition to such an antistatic agent, an antistatic agent comprising a surfactant can be further added. Such surfactants are not particularly limited, and for example, nonionic, anionic, cationic, and amphoteric surfactants can be applied. As a means for adding the antistatic agent to the ABS plate, it can be applied to the surface of the ABS plate after molding, but it is preferable to knead the ABS pellet before molding. It is also preferable to use a master batch in which an antistatic agent has been kneaded at a high concentration. In the case of a separate sheet containing an antistatic agent in this way, dirt and the like hardly adhere to the separate sheet, and even if the mouth of the eating and drinking container comes into direct contact, dust and the like are mixed into the eating and drinking container. Can be prevented. In particular, in the present invention, the antistatic effect is hardly reduced and is exerted permanently. In addition, since it is made of ABS, it can be washed and can be disposable. In addition, it can be washed without deteriorating its antistatic effect, so that it can be kept clean. Becomes possible,
Cost reduction can be achieved. Also, since it can be recycled and used, it is desirable from the viewpoint of resource protection.

Further, it is desirable that an antibacterial agent is contained in addition to the antistatic agent. As the antibacterial agent, various ones can be applied, but those having excellent antifungal properties are preferable, and a soluble glass containing an antibacterial metal such as silver, copper, or zinc, particularly silver ion is preferable. The antimicrobial agent can be contained by applying the antimicrobial agent to the molded product, but it is preferable to add the antimicrobial agent to the material before molding as appropriate, which is very simple. Therefore, the application step after molding is not necessarily required. Except for the material cost of the antibacterial agent itself, there is almost no increase in cost due to the step of adding the antibacterial agent, and the cost is reduced as compared with the paper-made one. be able to.

When applying an antibacterial agent, for example, a method by spraying, a method by transfer, a method by immersion and the like can be applied. In the application method by spraying, a spray-type application method using centrifugal force is preferable, and the amount of application can be adjusted by controlling the number of revolutions. However, since the antibacterial agent is applied in the form of a mist, it must be spread uniformly in a film form. In the application method by transfer, for example, a method of attaching a liquid antibacterial agent to the roll surface and transferring the liquid antibacterial agent to the surface of the molded body by a gravure method can be mentioned, but the amount of the antibacterial agent applied depends on the unevenness formed on the roll surface. Due to restrictions, changing the application amount requires changing the roll itself, which is inconvenient. In the application method by immersion, it is performed by passing through a tank filled with a liquid antibacterial agent, and although the application is highly reliable, the immersion time is restricted by the requirements such as the take-up speed and the liquid level, and the application amount is It is difficult to adjust.

In the case of a melting glass containing silver ions, the melting glass preferably has a particle size of 0.4 to 49 μm. If it is larger than this, the frictional resistance of the surface of the separate sheet increases, and the slip of the container placed on the separate sheet may be deteriorated. The content of the antibacterial agent is not particularly limited as long as it can exhibit antibacterial properties, but is preferably 0.1 to 10% by weight,
It is preferable that the amount of silver ions eluted is 0.4 to 50 μg / 100 cm ² / day. When less than 0.4 [mu] g / cm ² / day, the antibacterial effect is not sufficient, when it is more than 100 [mu] g / cm ² / day, because the increase in antibacterial effect is poor despite the increased cost. In the case of a separate sheet containing an antibacterial agent, bacteria and the like do not propagate on the separate sheet, and even if the mouth of the food and drink container comes into direct contact, contamination of the bacteria and the like into the food and drink container is prevented. Can be prevented. In particular, since the separate sheet of the present invention contains a hydrophilic polymer as an antistatic agent, the antibacterial effect of an antibacterial agent comprising a soluble glass containing silver ions can be further enhanced. That is, since the antistatic agent absorbs moisture, the dissolution rate of the antibacterial agent is increased, and the antibacterial effect is improved. Therefore,
With the separate sheet of the present invention, the antistatic effect and the antibacterial effect are synergistically exhibited. Further, since the antistatic agent composed of a surfactant forms a film on the surface, there is a possibility that the antibacterial effect is impaired when used in combination with an antibacterial agent. It is also suitable for use with antibacterial agents. Note that other additives such as a pigment, a heat stabilizer, a weather stabilizer, a flame retardant, a reinforcing agent, and the like can be added to the ABS within a range that does not impair safety or the like. The means for forming such a separate sheet is not particularly limited, and various known means can be applied.
Extrusion molding has a possibility that the antistatic effect may be impaired due to the orientation phenomenon as compared with injection molding.

The separate sheet may be formed of a single-layer plate made of ABS, but is more preferably a multilayer having a surface layer and a core layer. in this case,
From a two-layer structure of a surface layer and a core layer, a three-layer structure in which a core layer is interposed between two surface layers, and four or more layers in which many layers other than the core layer are interposed between the surface layers There is a multilayer structure,
A three-layer structure is optimal. In this multilayered structure, both the core layer and the surface layer are made of ABS, but at least the surface layer contains an antistatic agent or an antibacterial agent (hereinafter abbreviated as "antistatic agent etc."). Is enough. When molded using an ABS material to which an antistatic agent or the like has been added, the antistatic agent or the like is uniformly dispersed in the molded product, and is dispersed not only on the surface portion but also on an inner portion that is not exposed to the surface. You. In such a device, it is the antistatic agent or the like present on the surface or the antistatic agent or the like bleeding on the surface that actually exhibits the charging effect (or the antibacterial effect), and the thickness of the molded body is reduced. When the thickness is thick, the antistatic agent or the like located far from the surface does not sufficiently exert its antistatic action (or further antibacterial action), and the added antistatic agent or the like cannot be fully utilized. However, if the multilayer body has a surface layer exposed to the outside and a core layer located inside the multilayer body, and the surface layer contains an antistatic agent or the like, the antistatic agent or the like is a separate sheet. Since most of the additives used can be effectively used without deteriorating the physical properties of the entire separator sheet, the use of antistatic agents The amount can also be reduced. Further, when a multilayer body having a core layer and a surface layer is used, a new ABS is used for the surface layer in order to maintain a high degree of cleanliness, and a recycled ABS is used for the core layer that is not exposed on the surface. be able to. In other words, by reusing old and discarded separate sheets as the material for the core layer, and by using new materials only for the surface layer with a small amount of use, both high cleanliness and recyclability are improved. In addition to being beneficial from the environmental and resource issues, it is also possible to reduce costs.

The total thickness of the surface layer is preferably from 3 to 30%, more preferably from 10 to 20%, based on the total thickness. That is, in the case of a three-layer structure, in order to make the surface layer 20%, the ratio of each layer is set as follows: surface layer: core layer: surface layer = 1:
8: 1 may be used. For example, to make the thickness of the surface layer 10% when the total thickness is 2 mm, the surface layer / core layer /
Each thickness of the surface layer is 0.1 mm / 1.8 mm / 0.1 mm. In the case of this multilayer body, an antistatic agent or the like is added to the surface layer. Therefore, when the thickness of the surface layer is small, the amount of the antistatic agent or the like is small, but the thickness of the surface layer is 10%.
In this case, practically, a sufficient amount of an antistatic agent or the like is added. On the other hand, if the thickness is more than 30%, the amount of an antistatic agent or the like which does not contribute to the antistatic effect (or further the antibacterial effect) increases, and the stability decreases when manufactured by extrusion. As the core layer, it is possible to use a material different from the surface layer, for example, polypropylene or a different type of ABS material, but the core layer and the surface layer may use the same type of ABS material. desirable. If the type of the material is different, delamination is likely to occur between the core layer and the surface layer,
This is because the strength is reduced and the recyclability when reused is reduced.

The method for producing the multilayer body is not particularly limited, and includes a coating method, a laminating method, a co-extrusion method, and the like. It is. In a method of laminating an ABS film containing an antistatic agent or the like as the surface layer on the core layer, for example, a means such as heat lamination or dry lamination may be applied. Thermal lamination uses heat fusion and can utilize the heat of fusion during sheet molding and can reduce running costs, but only when the core layer and surface layer have compatibility. Not applicable. Dry lamination uses an adhesive and can be applied to the case where incompatible layers are laminated. Various adhesives can be appropriately selected and used, and a two-pack type adhesive capable of adjusting the curing speed and the like is preferable.

The stacking of the eating and drinking containers is performed by repeatedly placing the eating and drinking containers and the separate sheets for each stage alternately. These operations are automated by a machine, and a plurality of food and beverage containers in each stage are collectively slid on a separate sheet and moved to be arranged at a predetermined position. Therefore, since the food and beverage containers slide on the separate sheet, and are aligned and arranged, the flatness of the separate sheet and the smoothness of the upper surface (loading surface) thereof are important. That is, if the separate sheet is distorted or is easily bent by loading the eating and drinking container, the arrangement of the eating and drinking container is disturbed, and the sliding of the eating and drinking container is not smooth. In addition, if the coefficient of friction is large and the smoothness is insufficient and the slippage is poor, the eating and drinking container does not slide on the separate sheet, the eating and drinking container is not smoothly arranged at a predetermined position, and the eating and drinking container may fall. There is.
In addition, even if the coefficient of friction is small and the smoothness is high and slipping occurs too much, it becomes difficult to align and arrange the eating and drinking containers, and the stability after that is reduced, and the misalignment is likely to occur. ABS is extremely excellent as such a lightweight, flat and suitable surface. If it is other resin such as polypropylene (PP) or polystyrene, it is easy to bend, cannot maintain flatness like ABS, and cannot exhibit smoothness, and slides a food and drink container smoothly. Although it cannot be performed, ABS is less likely to bend and the food and beverage container can be smoothly slid and arranged. Flexural modulus is 1 to maintain flatness
0000 kg / cm ² or more, preferably 20,000 kg / cm ²
More preferably, it is at least g / cm ² . In addition, since food and drink containers may be loaded for a long time, it is desirable to have high creep performance. In these respects, A
The BS plate shows extremely excellent properties.

In order to smoothly slide the food and drink containers loaded on the upper surface as a separate sheet for the food and drink containers, the roughness of the upper surface is 10 points average roughness Rz (JIS B0601-JIS).
Based on 1982, cutoff value: 0.8mm, measurement length: 25m
m) is preferably from 50 to 200 μm, and
More preferably, it is 140 μm. If it is coarser than this range, it will be difficult to smoothly slide the food and drink container, and even if it is smoother than this range, the loading state will be unstable. In addition, although it is affected by the material, weight, shape of the bottom surface, etc. of the food and drink container, in order to exhibit suitable smoothness as a separate sheet, the coefficient of friction between the upper surface of the separate sheet and the food and drink container loaded there is required. Is desirably 0.15 to 0.5. In order to satisfy these requirements such as smoothness, it is desirable to form irregularities such as embossments on the upper surface of the separate sheet. The formation of the grain is facilitated by forming a desired grain pattern on a mold at the time of molding the separate sheet. In addition, in order to protect the food and drink container, it is preferable that the surface of the separate sheet has elasticity.However, in order to smoothly slide the food and drink container, a material having an appropriate hardness on the surface is preferable. If the elasticity is too high, it is unsuitable, and from this point, ABS is also suitable.

[0015] Separate sheets are stacked and stored until they are used. When used, the separate sheets are taken out one by one from above and provided for use. At this time, the separate sheets may come into close contact with each other, making it difficult to take out one sheet at a time. In particular, when the separation sheet is mechanically transported and the separation sheet is taken out by suction using a robot arm, the separation sheets are likely to adhere to each other, which is inconvenient. In order to prevent such separate sheets from adhering to each other, it is desirable to form irregularities by embossing also on the lower surface of the separate sheet. As such a grain, those having a surface roughness larger than that of the upper surface and 200 μm or less are preferable. Or
The coefficient of friction with the food and beverage container contacting the lower surface is 0.2 to 0.5.
Is desirable, and more preferably 0.3 to 0.4. The formation of the unevenness in this range contributes to the prevention of the above-mentioned adhesion and also contributes to the stability of the stacked state, and also to the prevention of the displacement of the load at the time of conveyance or the like.

[0016]

【Example】

Example 1 ABS resin was blended with 1% by weight of powdered polyethylene glycol and 15% by weight of powdered polyamide, melt-kneaded, and extruded to form a surface layer. 1.8mm thickness with core layer
Was formed into a flat composite sheet having a three-layer structure. With respect to a test piece obtained by cutting this separate sheet into 32 × 32 mm, the electric resistance value of the surface was measured. For the measurement, “HP4339” manufactured by Hewlett-Packard Co., Ltd.
A "was used. As a comparative example, the same separate sheet was molded except that the antistatic agent was not blended, and evaluated similarly. Table 1 shows the results.

[Table 1] From Table 1, it can be seen that the separate sheet of this example has a high antistatic effect and suppresses adhesion of dust and the like.

[Example 2] Further, for ABS resin,
1% by weight of polyethylene glycol and 15% of polyamide
5% by weight and a soluble glass containing silver ions
An antibacterial test and an antifungal test were performed on the separate sheet added and molded in the same manner as in Example 1 above. The antibacterial test was carried out in accordance with the Society of Inorganic Antibacterial Agents for Silver, etc., "Voluntary Standards for Silver and Other Inorganic Antibacterial Agents and Antibacterial Testing Method, Antibacterial Testing Method for Antibacterial Products I (1995 Edition) Film Adhesion Method" Escherichia coli was used as a test bacterium. Bacterial solution is dropped on the sample, and the solution is kept under the conditions of 35 ± 1 ° C. and 90% or more of relative humidity.
The number of viable bacteria after storage for a time was measured. As a result, E. coli was not detected. The antifungal test was carried out according to ASTM G21.
After culturing at -30 ° C and a relative humidity of 85% or more for 31 days, the state of mycelial growth was observed with the naked eye and a stereoscopic microscope.
As a result, no mold growth was observed.

[0018]

According to the separate sheet of the present invention, antistatic properties can be exhibited with almost no increase in cost, the adhesion of dust and the like can be reduced, and the container can be kept clean. In addition, since cleaning is possible and reuse is possible, a long life can be achieved, which is desirable from the viewpoint of resource conservation. In particular, when an antibacterial agent composed of a soluble glass containing silver ions is further added, the antibacterial effect is particularly large because the antistatic agent is contained. Therefore,
The present invention, which exhibits the synergistic effect of the antistatic effect and the antibacterial effect, is extremely excellent in a separate sheet in which the chargeability and the antibacterial property are particularly important. Also, the separate sheet is composed of a multilayer body, and an antistatic agent or a further antibacterial agent is added to the surface layer,
The use efficiency of the antistatic agent and the like is improved, and the amount of the antistatic agent and the like used can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a use state of a separate sheet.

[Explanation of symbols]

 10 Separate sheet 14 Food and beverage container

Claims (4)

[Claims] An acrylonitrile containing polyethylene glycol and a polyamide in a separate sheet interposed between a plurality of containers when they are stacked.
A separate sheet comprising a butadiene-styrene resin. 2. The separate sheet according to claim 1, further comprising a melting glass containing silver ions. 3. A separate sheet interposed between a plurality of food and beverage containers when they are stacked, comprising a multilayer body having a surface layer made of acrylonitrile-butadiene-styrene resin and a core layer. Is a separate sheet to which polyethylene glycol and polyamide are added. 4. The separate sheet according to claim 3, wherein the surface layer further includes a soluble glass containing silver ions.