JPH04112054U - battery packaging - Google Patents

Abstract

(57) [Summary] [Purpose] In heat-shrink packaging for batteries, we aim to reduce pollution in terms of waste disposal, have the appearance characteristics of battery packaging, and be easy to handle in vending machines. The present invention provides a battery package. [Structure] This is a battery packaging body that uses shrink wrapping polypropylene film based on ethylene-propylene copolymer and mixed with petroleum resin.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a battery that uses heat-shrinkable packaging for batteries or heat-shrinkable packaging for internal parts of batteries. Relating to a package.

0002

[Conventional technology]

Conventionally, regarding the external packaging of batteries or the heat shrink packaging of internal battery parts, Heat-shrinkable films such as polyvinyl chloride are used.

0003

[Problem that the idea aims to solve]

PVC film has a large change in film characteristics due to changes in ambient temperature. When the temperature exceeds around 40℃, the coefficient of friction of the film increases, As the temperature increases, the breaking strength of the film decreases. For example, in a battery vending machine, etc., the contact area between stacked battery packs is If it is large, the frictional force at the contact will increase when the ambient temperature reaches around 40°C, causing blockage. The battery packaging may not be automatically ejected from the vending machine due to the king phenomenon. In addition, when the ambient temperature of the same vending machine drops to around 0°C, the battery packaging is allowed to fall freely. There was a drawback that the rate of destruction of the package increased when the package was exposed.

0004 Moreover, PVC film generates chlorine gas when incinerated in terms of waste disposal. There is also the problem of environmental pollution caused by batteries, making the problem of battery disposal even more difficult. When heat shrink packaging such batteries, the present invention does not require incineration in terms of waste disposal. It uses a polypropylene film that does not generate chlorine gas, and has good heat shrinkability at low temperatures. Excellent, does not cause wrinkles or pock-like shrinkage unevenness due to heat shrinkage at low temperatures, and is better than conventional poultices. It has the same appearance characteristics as battery packaging made of polyvinyl chloride heat-shrinkable film. However, the film properties due to changes in ambient temperature, that is, the increase in the coefficient of friction around 40℃, , the decrease in breaking strength near 0°C is extremely small, making it easy to handle in vending machines, etc. The purpose is to provide pond packaging.

[0005]

[Means to solve the problem]

The present invention, as the first idea to solve the above problems, uses 0.2 to 10 mol% of ether. A crystalline ethylene-propylene copolymer containing tyrene as a monomer unit is used as a base. Mix this with petroleum resin at a ratio of 2 to 50 wt%, and after forming the film, heat it at a temperature of 110℃ or less. It is characterized by using a stretched polypropylene film for shrink wrapping.

[0006] The second idea is to create crystals containing 0.2 to 10 mol% ethylene in monomer units. Based on a polyethylene-propylene copolymer with 2 to 3 butene-based polymers added to it. Mix 50wt% of petroleum resin and 2 to 50wt% of petroleum resin, and after forming the film, spread it at a temperature of 110℃ or less. It is characterized by using a stretched polypropylene film for shrink wrapping.

[0007]

[Effect]

In the present invention, the film used for the battery packaging is made of the above-mentioned specific crystalline ethylene film. Based on lene-propylene copolymer, the first idea included specific petroleum resins. In the second design, in addition to the petroleum resin, a specific and specific amount of butene-based The polymer formulations are mixed, the resulting composition is formed into a film-like material, and this is uniaxially coated. Alternatively, it is a polypropylene film for shrink wrapping that has been stretched biaxially or more. The friction coefficient of the body at high temperatures (around 40℃) decreases, and the fracture strength at low temperatures (around 0℃) decreases. increases. In addition, the heat shrinkability of polypropylene film at low temperatures (around 150 °C) has been improved, making it possible to perform heat shrink packaging at low temperatures.

[0008]

【Example】

Examples will be described based on the drawings. This example relates to an external package for a battery. Then, as shown in Figures 1 and 2, four cylindrical AA batteries were arranged horizontally in parallel. A heat-shrinkable cylindrical film is applied to the material, and then passed through a heat-shrinking device (not shown). It is used for heat shrink packaging.

[0009] Package 1 consists of four dry batteries 2 wrapped in heat-shrinkable film 3. Battery 2 is an AA dry battery, but is not limited to this, and can be anything such as AA or AA. It's okay. Heat-shrinkable film 3 is a polypropylene-based film for shrink wrapping, and is crystalline. It is formulated based on ethylene/propylene copolymer, especially this crystalline ethylene copolymer. The lene-propylene copolymer contains 0.2 to 10 mol% ethylene, preferably 2 to 7 mol%. is a simple crystalline ethylene-propylene copolymer. Not a combination. In other words, if ethylene is not polymerized in monomer units, This is because low-temperature shrinkage becomes insufficient. At this time, the ethylene content is less than 0.2 mol% However, the shrinkage rate is insufficient even if the ethylene content is increased to 10 mol% or more. There is no improvement, and on the contrary, the film becomes weaker.

0010 The petroleum resins used in the formulation are aliphatic petroleum resins, hydrogenated petroleum resins, Examples include alicyclic saturated hydrocarbons such as aromatic petroleum resins, and there are no particular limitations. above stone The oil resin is used in an amount of 2 to 50 wt%, but if it is less than 2 wt%, the desired low temperature yield of the present invention is not achieved. The shrinkability is insufficient and the shrinkage finish is poor.On the other hand, if it exceeds 50wt%, the film after stretching is It has a very strong tendency to shrink even at room temperature. Preferably it is 5 to 40 wt%.

[0011] In the second idea, a butene-based copolymer is further used in addition to the petroleum resin. It takes Examples of butene-based copolymers include polybutene, crystalline butene-propylene copolymers, etc. There are no particular restrictions. In this case, the polybutene preferably has a low molecular weight of 300 to 2500. Examples include those with a molecular weight, but it is of course not limited to this. It can also be used outdoors as needed. In addition, the butene-propylene copolymer is Examples include those with a butene content of 0.2 to 30 mol%, preferably 2 to 25 mol%. Ru.

0012 The reason why butene is set at 0.2 to 30 mol% is that if the butene content is less than 0.2 mol%, it will be low. Insufficient heat shrinkability results in poor shrinkage finish, while if the butene content exceeds 30 mol%, It is also possible that it is difficult to blend uniformly when the petroleum resin is melted. Low-temperature stretching of the film is difficult as it tends to cause problems such as shrink-eye and film thickness fluctuations. As a result, low-temperature shrinkage becomes worse. Of course, such numerical values are not limited and may exceed the above range. Other materials can also be used as needed.

[0013] The above butene-based polymer is used in an amount of 2 to 50 wt%, but if it is less than 2 wt%, Insufficient low-temperature shrinkability results in poor shrinkage finish. On the other hand, even if it exceeds 50wt%, it has low-temperature shrinkability. It does not contribute to the improvement of It is. As mentioned above, based on the above-mentioned specific crystalline ethylene-propylene copolymer, In the first design, a specific amount of petroleum resin was mixed with it, and in the second design, petroleum resin was mixed with it. In addition to fat, a specific and specific amount of butene-based polymer is mixed and the resulting composition is A heat-shrinkable film is formed by forming a film on an original fabric and stretching it uniaxially or biaxially. Create room 3.

[0014] The thickness of the film 3 is 20 to 70 μm; if it is less than 20 μm, the strength of the package will be weak; If the thickness exceeds μm, equipment adaptability will deteriorate. At this time, as an example of longitudinal uniaxial stretching, a roll rotating at a low speed at the front is generally used. The film is passed between the rearmost roll that rotates at high speed, and the rotational speed ratio of both rolls is Stretch by. The stretching temperature at this time is 80℃~110℃, the stretching ratio is 2~10 times, Preferably it is about 3 to 6 times.

[0015] On the other hand, as an example of horizontal uniaxial stretching, a tenter method is preferably used. At this time, it was extended The stretching temperature is 60 to 110°C, and the stretching ratio is 3 to 10 times, preferably 5 to 8 times. Also, below Sequential biaxial stretching in the longitudinal and lateral directions, simultaneous biaxial stretching, etc. are also possible under the conditions shown above. The above is a flat film, but in addition to this, a tube-shaped raw film can also be used as an inflator. It is also possible to carry out longitudinal uniaxial stretching, horizontal uniaxial stretching, simultaneous biaxial stretching, etc. using the double method. this place The combined fabric is heated to 60 to 110 °C, and pressurized air is sent into the tube-shaped film to create a vertical film. Alternatively, it may be uniaxially stretched in the horizontal direction or simultaneously stretched in the vertical and horizontal directions, for example, in the vertical direction. Examples include 1 to 5 times, and 1 to 5 times in the horizontal direction. In addition, in the first idea, 80 to 100 It can be stretched at 65-90°C in the second invention.

[0016] The heat shrinkage rate of the polypropylene heat-shrinkable film3 created in this way is , dipping in glycerin bath 100 °C, 30 seconds, 10-20% in longitudinal direction, 40-50% in transverse direction, The coefficient of friction was 0.3 to 0.7 (measurement method ASTM D-1894). The heat-shrinkable film 3 was made into a narrow band-like film with an appropriate width dimension, and four Apply ultrasonic sealing 4 to the two longitudinal edges of the dry battery 2 according to its dimensions. At the same time, the cylindrical film 3a is created by cutting the film to an appropriate length. Seal at this time The strength is 1.0-2.0 kg/cm.

[0017] Next, as shown in Figure 2, a cylindrical film 3a is attached to the dry battery 2 by an appropriate method. Ru. At this time, the direction of application may be in the horizontal direction as shown in the package 1 in Figure 1, or As shown in FIG. 3, it may be in the vertical direction depending on the shape of the package 1. cylindrical film 3a Pass the adhered dry battery 2 through an appropriate heat shrinking device consisting of a heating tunnel, etc. Accordingly, the cylindrical film 3a made of polypropylene film for shrink wrapping is shown in Figure 1. As shown in the figure, it thermally shrinks beautifully to form a package 1 for a dry battery 2.

[0018] Also, the method of attaching the cylindrical film 3a to the dry cell battery 2 may be done manually, but An automatic deposition device may also be used. Also, the heat shrinking device may be a tunnel type that uses a heater, hot air, etc. , a heat shrinking device that does not have a tunnel and uses only hot air may be used, or any other suitable device may be used. However, the heat shrinkage conditions are 140-150°C for about 5 seconds.

[0019] The polypropylene film for shrink wrapping of the present invention formed as described above is The used packaging 1 and the conventionally used polyvinyl chloride heat-shrinkable film were Regarding the battery packaging in the comparative example used, Table 1 shows the blocking phenomenon.

[0020]

[Table 1]

[0021] In addition, as shown in Table 2, the results of the free fall test at low temperatures indicate that the packaging according to the present invention 1 has high reliability over a wide range of ambient temperatures.

[0022]

[Table 2]

[0023] This example was about packaging four dry batteries, but it was also used for packaging along with dry batteries. A mount may be inserted, and the number is not limited to four, but may be two as shown in Figure 3. It's fine, and you can wrap it in either vertical or horizontal directions as appropriate. Furthermore, this invention is suitable for use other than dry batteries. It is stored not only in the outer packaging of the dry battery, but also in the outer can of the dry cell, and it combines various internal parts into one. Insulating the exterior of zinc cans for storage and internal packaging to prevent leakage. also applies.

[0024] An example of the inner packaging is shown in FIG. The dry battery 5 is equipped with a zinc can 7 that houses the internal parts 6. , an outer can 9 encasing the zinc can 7, and insulating the zinc can 7 and the outer can 9. In order to prevent liquid leakage from the zinc can 7, the zinc can 7 has an insulating heat sink. Wrapped in shrinkable film8. Here, the heat shrinkable film 8 is covered with the shrink wrap. It becomes possible to use a wearable polypropylene film.

[0025]

[Effect of the idea]

The battery package according to the first invention is bonded to a polypropylene film for shrink wrapping. As a crystalline ethylene/propylene copolymer, a specific mol% of ethylene is used as a monomer. Since we used the unit content, it is simply a crystalline ethylene/propylene copolymer. It has superior heat shrinkability at low temperatures (around 150 degrees Celsius) compared to products that use body parts, and can be easily heat-shrinked. In addition to making packaging possible, the coefficient of friction of the package at high temperatures (around 40℃) is reduced and (near 0℃), making it easier to handle in vending machines, etc. It has the effect of becoming.

[0026] Also, since it uses polypropylene film, it cannot be incinerated in terms of waste disposal. It does not generate chlorine gas even when used, and has the same appearance characteristics as conventional PVC film packaging. A beautiful package is obtained. In the second invention, by adding a butene-based polymer to the first invention, Compared to other products, the heat shrinkability at low temperatures is improved, and beautiful packaging can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a dry battery package.

FIG. 2 is an explanatory diagram of a dry battery covered with a cylindrical film.

FIG. 3 is an explanatory diagram of another embodiment of the package.

FIG. 4 is an example of the inner packaging of a dry battery.

[Explanation of symbols]

1 Packaging 2 Dry battery 3 Heat shrinkable film

──────────────────────────────────────────────── ─── Continued from the front page (51) Int.Cl. ⁵ identification code Internal reference number FI Technical display location C08L 23:16 (72) Inventor Mariko Sugimoto 163 Morikawahara-cho, Moriyama City, Shiga Prefecture Gunze Co., Ltd. Moriyama Factory Inside

Claims (2)

[Scope of utility model registration request] [Claim 1] Based on a crystalline ethylene-propylene copolymer containing 0.2 to 10 mol% ethylene in monomer units, mixed with this at a proportion of 2 to 50 wt% of petroleum resin, and heated at 110°C after film formation. A battery packaging body characterized by using a polypropylene film for shrink wrapping that is stretched at the following temperature. [Claim 2] Based on a crystalline ethylene-propylene copolymer containing 0.2 to 10 mol% of ethylene in monomer units, 2 to 50 wt% of a butene-based polymer, and 2 to 50 wt% of a petroleum resin. 1. A battery packaging body characterized by using a polypropylene film for shrink wrapping, which is formed by mixing the polypropylene film in the following proportions and stretching the film at a temperature of 110°C or less after film formation.