JPH07255831A - Manufacture of film for first-aid sticking plaster - Google Patents

Abstract

PURPOSE:To provide a film which does not substantially contain a plasticizer and by which stress relaxation at elongation time becomes fast and which does not press the affected part by molding polypropylene type resin, which has specific weight average molecular weight and whose resin eluting quantity at a specific temperature falls within a constant range, as a film. CONSTITUTION:In polypropylene type resin whose weight average molecular weight falls within a range of 80000 to 500000, the polypropylene type resin having the composition in which resin eluting quantities within respective temperature ranges of 0 to 10 deg.C, 10 to 70 deg.C, 70 to 95 deg.C and 95 to 125 deg.C by a cross classification method respectively fall within ranges of 45 to 80wt.%, 50 to 35wt.%, 1 to 30wt.% and 5 to 35wt.% of a total polypropylene type resin quantity, is molded under conditions where a draft ratio is 5 to 30 and a frost line height is 1 to 7 times a metal mold diameter by using an inflation die 6, and a necesary film 2 is obtained. The film 2 is laminated on a process paper 1 through a heating laminate roller 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a film for an emergency adhesive bandage, which is formed by using a specific polypropylene resin, and more specifically, a first-aid adhesive bandage that is soft and does not press the affected area and has a good texture is obtained. The present invention relates to a method for manufacturing a film for a first aid bandage.

[0002]

2. Description of the Related Art In general, a bandage, especially a first-aid bandage, is prepared by applying a pressure-sensitive adhesive to the surface of a soft film, sticking gauze or the like on top of it, punching it to a specified size, and then individually wrapping it on both sides. Are piled up and further cut into a predetermined size.

As a soft film used for such a first aid bandage, in general, due to its price and ease of use,
A material containing a plasticized polyvinyl chloride (hereinafter referred to as plasticized PVC) as a main component, which is obtained by a calendar method or a sol cast method, has been widely used. However, since the plasticized PVC contains a large amount of plasticizer, the plasticizer migrates from the film to the pressure-sensitive adhesive, the pressure-sensitive adhesive strength of the pressure-sensitive adhesive decreases with time, and the adhesive strength between the film and the pressure-sensitive adhesive is reduced. However, there was a drawback that the adhesive tape was easily peeled off. In addition, plasticized PVC is often used for medical purposes,
In recent years, from the viewpoint of environmental issues, PVC containing chlorine
The pros and cons of using is discussed in all areas.

For this reason, recently, a flexible and stretchable polyolefin resin has been actively developed as a material to replace plasticized PVC. Examples of such polyolefin resins include films using polyethylene, ethylene-vinyl acetate copolymer, polybutadiene, ethylene-propylene copolymer and the like. As a film for first-aid bandages, Japanese Patent Publication Sho 57-
In Japanese Patent No. 11342, a polyolefin composition made of at least one of ethylene-α-olefin copolymer, LDPE (low density polyethylene) and PP (polypropylene) is stretched 1.5 to 3.5 times, Kaisho 6
2-82967 discloses a film comprising a hydrocarbon-based elastomer such as ethylene-propylene rubber or an ethylene-propylene-diene terpolymer and a polyolefin blend such as an ethylene-vinyl acetate copolymer. .

[0005]

However, the film as described above does not have sufficient stretchability and stress relaxation property at the time of application, which is required for the first aid bandage. Therefore, the applied film, that is, the first-aid bandage is often loosened or torn immediately and is not suitable for actual use.

The present invention overcomes the above-mentioned conventional drawbacks. By using a specific polypropylene resin, the present invention does not substantially contain a plasticizer, has flexibility and stretchability, and is excellent in stretchability. Stress relaxation is fast, does not press the affected area,
An object of the present invention is to provide a method for producing a film for first aid bandages, which has a good texture and is an alternative to conventional plasticized PVC films.

[0007]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention have selected, as a resin component, a polypropylene resin having a specific weight average molecular weight and having a resin elution amount in a certain range at a specific temperature. By molding into a film,
It has been found that the above object can be achieved, and the present invention has been completed based on the findings.

The method for producing a film for first aid bandages according to the present invention has a weight average molecular weight of 80,000 to 500,000.
A polypropylene resin within the range is used. In this polypropylene resin, the resin elution amount by the cross fractionation method at 0 ° C. or higher and 10 ° C. or lower is 45 to 80% by weight of the total polypropylene resin amount, and the resin elution amount at more than 10 ° C. and 70 ° C. is the total polypropylene. 5 to 35% by weight of the amount of the system resin, the resin elution amount at a temperature higher than 70 ° C and lower than 95 ° C is 1 to 30% by weight of the total amount of the polypropylene resin,
The resin elution amount at more than 5 ° C. and 125 ° C. or less is characterized by having a composition in the range of 5 to 35% by weight of the total polypropylene resin amount.

In a preferred embodiment, the polypropylene resin is a propylene-ethylene copolymer or propylene-α-olefin copolymer resin. In the presence of a titanium compound catalyst and an aluminum compound catalyst, these resins are prepared by first polymerizing the first propylene-based resin in the first stage, and then in the second and subsequent stages, the produced titanium-containing propylene-based resin and the above In the presence of compound catalyst,
It is characterized by being obtained by copolymerizing propylene and ethylene, or propylene and α-olefin.

In a further preferred embodiment, the titanium-containing propylene resin produced in the first stage is a propylene homopolymer, a propylene-ethylene copolymer, or a propylene-α-olefin copolymer.

The first method for producing a film for a first-aid bandage according to the present invention uses the above polypropylene resin as a draft ratio of 5
-30, and the frost line height is 1 to 7 times the die diameter, and is formed by the inflation method.

A second method for producing a film for first-aid bandages according to the present invention comprises the above polypropylene-based resin and a draft ratio of 5
˜50, and the frost line height is 1 to 7 times the die diameter, molding is performed by the inflation method, and then annealing is performed at an annealing temperature of 70 to 150 ° C.

The present invention will be described in detail below.

In the present invention, the weight average molecular weight of the resin can be measured, for example, by a high temperature GPC (150 CV) manufactured by WATERS. The polypropylene resin used in the present invention has a weight average molecular weight of 80,000 to 500,000, preferably 80,000 to 450,000,
More preferably, it is 100,000 to 400,000. When the weight average molecular weight is less than 80,000, the stretchability or strength of the film is insufficient, and when it exceeds 500,000, sufficient flexibility cannot be obtained.

The amount of resin eluted by the cross fractionation method used in the present invention is measured as follows. First, dissolve the polypropylene resin in o-dichlorobenzene at 140 ° C or the temperature at which the polypropylene resin is completely dissolved,
Cooling at a constant rate, a thin polymer layer is formed on the surface of an inert carrier prepared in advance in the order of increasing crystallinity and increasing molecular weight. Next, the temperature of the generated polymer layer is continuously or stepwise increased, and the concentrations of the components eluted in sequence are detected,
The composition distribution (crystallinity distribution) is measured <temperature rising elution fractionation>. At the same time, the molecular weight and molecular weight distribution of the component are measured by high temperature GPC. For example, the temperature rising elution fractionation (TREF = Temperature Rising Elutio
n Fractionation part and high temperature GPC (SEC = Size Ex
Cross-fractionation chromatograph device <CFC-T15, which is equipped with
Model OA: manufactured by Mitsubishi Petrochemical Co., Ltd.> can be used.

The polypropylene resin used in the present invention is
The resin elution amount at 0 ° C. or higher and 10 ° C. or lower according to the cross fractionation method is 45 to 80% by weight, preferably 50 to 75% by weight, based on the total amount of polypropylene resin. If this elution amount is less than 45% by weight, the film lacks flexibility, and
If the amount exceeds 5% by weight, sufficient strength as a film cannot be obtained.

This resin is obtained by the above-mentioned cross fractionation method 10
The resin elution amount at a temperature higher than 70 ° C and lower than 70 ° C is 5 to 35% by weight, preferably 5 to 30% by weight, based on the total amount of polypropylene resin. If it is less than 5% by weight, the film lacks flexibility,
If it exceeds 35% by weight, the deformation recovery of the film is poor.

The resin elution amount by the cross fractionation method above 70 ° C. and below 95 ° C. is 1 to 3 of the total polypropylene resin amount.
It is 0% by weight, preferably 1 to 25% by weight. 1
If it is less than 30% by weight, the recovery of deformation of the film is poor, and if it exceeds 30% by weight, the strength of the film becomes a problem.

Finally, the resin elution amount by the cross fractionation method above 95 ° C. and below 125 ° C. is 5 to 35% by weight, preferably 5 to 30% by weight of the total polypropylene resin amount.
Is. If it is less than 5% by weight, there is a problem in the strength of the film, and if it exceeds 35% by weight, the flexibility of the film is poor.

The polypropylene resin used in the present invention is 0 ° C. or higher and 10 ° C. or lower according to the above cross fractionation method.
125 ° C, 70 ° C or higher, 70 ° C or higher, 95 ° C or lower, and 95 ° C or higher, 125 ° C
The weight average molecular weight of each eluted resin at 10 ° C or lower is 10
30,000-300,000, 70,000-500,
5,000, 50,000 to 500,000, 50,000
It is preferably in the range of ˜500,000.

In the polypropylene resin used in the present invention, the elution amount in each temperature range and the weight average molecular weight within the above range are very important for controlling physical properties such as elastic modulus, strength and ductility of the film. Is important to.

The above polypropylene-based resin is produced, for example, by the following multistage polymerization method. First, as a first step, polymerization is carried out in the presence of a titanium compound catalyst and an aluminum compound catalyst using a propylene monomer and optionally an α-olefin monomer other than propylene to obtain a first polypropylene resin. The polypropylene resin may be a propylene homopolymer, a propylene-ethylene copolymer, a propylene-α-olefin copolymer, or the like. In the second step, a titanium-containing polypropylene-based resin and an olefin monomer (for example, ethylene, propylene, or α-olefin) are copolymerized in the presence of the above-mentioned compound in the presence of the titanium compound catalyst and the aluminum compound catalyst. Let me
A second polypropylene resin is obtained. The second polypropylene resin obtained by this two-step reaction may be a propylene-ethylene copolymer or a propylene-α-olefin copolymer. Similarly, a multi-step copolymerization reaction can be performed depending on the purpose. The feature of this production method is that the polymerization is not completed in one step, but multi-step polymerization of two or more steps is performed. This allows multiple types of polymers to be built up in succession, producing blend-type copolymers at the molecular level, which is quite different from conventional polymer blends.

Generally, in the case of polymer blends, one way to improve flexibility and stretchability is to increase the molecular weight of the rubber component to be blended. In the case of the polypropylene-based resin used in the present invention, the rubber component is a component (α-olefin-propylene, ethylene-propylene) produced in the reaction in the two or more steps described above,
Since this component has a high molecular weight, it has a high melt viscosity. This rubber component can be finely dispersed in the polypropylene resin obtained in the first step by using the above-mentioned multistage polymerization method. However, in a blending method using an ordinary extruder, when a rubber component having such a high molecular weight is used,
Since the melt viscosity is high, a resin having a finely dispersed morphology like the polypropylene resin used in the present invention cannot be prepared. Further, in a resin such as a polypropylene-based block copolymer obtained by a conventional reaction, the block component such as ethylene and α-olefin to be copolymerized is about the same as the main component polypropylene due to its manufacturing process. The limit is about 50% by weight, and the content is usually up to 30% by weight. For this reason, it has been very difficult to realize flexibility such as plasticized PVC in polypropylene resin. However, when the above-mentioned method is used, the copolymerization component is about 80 to
It becomes possible to contain up to 95% by weight, and plasticized P
A polypropylene resin having the same physical properties as VC can be obtained.

As such a manufacturing method, for example, there is a method described in Japanese Patent Application Laid-Open No. 4-224809. In this method, as a titanium compound, for example, titanium trichloride and magnesium chloride are co-ground, and this is orthotitanic acid n
A spherical solid titanium catalyst having an average particle diameter of 15 μm, which is obtained by treating with —butyl, 2-ethyl-1-hexanol, ethyl p-toluate, silicon tetrachloride, diisobutyl phthalate, or the like, is used. In this method, a silicon compound, especially diphenyldimethoxysilane, is added as an electron donor to the polymerization tank, and ethyl iodide is further added. Further, JP-A-3-97747 discloses that a titanium compound obtained by treating an adduct of magnesium chloride and alcohol with titanium tetrachloride and an electron donor is used. In addition to these methods, for example, JP-A-4-96912, JP-A-4-96907, JP-A-3-174410, and JP-A-2-170803.
No. 2, 170, 802 and No. 3, 20543.
No. 9, JP-A-61-42553 and the like describe such a manufacturing method. When manufacturing the polypropylene-based resin forming the film for first aid bandage of the present invention, any known method as described above may be used. Examples of actual resins obtained by such a production method include "PER" manufactured by Tokuyama Soda Co., Ltd. and "Cataloy" manufactured by Highmont Co., Ltd. Any of these can be used in the present invention.

In the present invention, each of the above resin layers contains a stabilizer such as an antioxidant and an ultraviolet absorber, a filler such as precipitated barium sulfate, talc, calcium carbonate, mica and titanium oxide, and a coloring agent. Can be added.

Generally, in polypropylene resin, stress-
Taking a strain curve (hereinafter referred to as S-S curve), the initial rise is steep, yielding occurs when it is stretched by 20 to 30% by weight, and then the stress hardly increases up to about 100% stretching, so-called S- The phenomenon that the S curve bends occurs. In this case, the adhesive bandage has problems that it will be stretched when it is strongly pulled at the time of application, and that it will be difficult to re-apply it. Further, depending on the resin, the tensile strength at the initial stretching may be too large, and the film may become inflexible.

The present invention can provide a method for producing a film in which the tensile strength at the initial stretching is small and the SS curve is not twisted, that is, the film is rich in flexibility and has sufficient tensile strength.

The first method for producing a film for first aid bandages according to the present invention is a method in which the above resin is added by an inflation method.
It is to mold under a predetermined condition. This condition is that the draft ratio is 5 to 30 and the frost line height is 1 of the die diameter.
~ 7 times.

By inflation-molding the polypropylene resin used in the present invention, the flexibility, stretchability, and stress relaxation during stretching are maintained, and even when the adhesive plaster is applied or re-applied, it can be stretched to its full extent. Films with sufficient tensile strength can be obtained.

In this inflation molding, below the frost line, the film is stretched in both MD (longitudinal) and TD (width) directions. That is, the film is stretched at a high temperature, which causes some molecular orientation, so that the film as described above is obtained. Further, since this film is deformed at a high temperature, the residual strain is small and the thermal shrinkage is relatively good.

The draft ratio λL in the present invention is a value indicating the enlargement ratio in the MD direction given by the following equation.

ΛT λL = tD / tF Here, λT is a blow-up ratio, which is given by the ratio of the folded diameter of the final film to the die diameter, and is a value showing the enlargement ratio in the TD direction. Further, tD is the interval width of the mold, and tF is the final film thickness.

In the first manufacturing method of the present invention, this draft ratio is 5 to 30. If the draft ratio is less than 5,
It does not provide a film with sufficient tensile strength. On the other hand, when the draft ratio exceeds 30, the residual stress becomes large and a film in which heat shrinkage is excessively obtained is obtained.

The frost line in the present invention is a solidification line in which the extruded molten film becomes a solid.
In the first manufacturing method of the present invention, the height of the frost line is 1 to 7 times the die diameter. If the frost line height is less than 1 times the die diameter, it is difficult to form a stable film. On the other hand, if the frost line height exceeds 7 times the die diameter, a film having sufficient tensile strength can be obtained. Absent.

For the inflation molding in the first manufacturing method of the present invention, either an air cooling method or a water cooling method may be used.

A second method for producing a film for first aid bandage of the present invention is to mold the above resin by an inflation method under predetermined conditions and then anneal it at a predetermined temperature. The conditions for the inflation method are a draft ratio of 5 to 50.
And the frost line height is 1 to 7 times the die diameter,
The annealing temperature is 70 to 150 ° C.

By inflation-molding the polypropylene resin of the present invention, flexibility, stretchability,
Also, it is possible to provide a film that maintains stress relaxation during stretching and has sufficient tensile strength that does not fully stretch even when pulled strongly when the adhesive plaster is attached or reattached. Furthermore, by annealing the film, it is possible to suppress the heat shrinkage of the obtained film.

In the second manufacturing method of the present invention, this draft ratio is 5 to 50. If the draft ratio is less than 5,
A film having sufficient tensile strength cannot be obtained. On the other hand, when the draft ratio exceeds 50, blow-up becomes difficult and stable inflation molding cannot be performed.

In the second manufacturing method of the present invention, the height of the frost line is 1 to 7 times the die diameter. If the frost line height is less than 1 times the die diameter, it is difficult to form a stable film. On the other hand, if the frost line height exceeds 7 times the die diameter, a film having sufficient tensile strength can be obtained. Absent.

The inflation molding in the second manufacturing method of the present invention may also be carried out by the air cooling method or the water cooling method.

The annealing in the present invention is a step of heat-treating the film after inflation molding to relax the residual stress in the MD direction, and is a step for suppressing heat shrinkage as much as possible. In the second manufacturing method of the present invention, the annealing temperature is 70 to 150 ° C. When the annealing temperature is less than 70 ° C., the residual stress of the film cannot be sufficiently relaxed, and a film in which excessive heat shrinkage is obtained can be obtained. On the other hand, when the annealing temperature exceeds 150 ° C., the film is significantly softened and stable annealing cannot be performed.

As the annealing method in the present invention,
Examples include a method of heating along the surface of the roll and a method of heating with hot air or infrared rays in a hollow portion such as between rolls, but any method may be used.

The thickness of the film obtained using the method for producing a film for first aid bandage of the present invention is 15 to 300 μm.
Is desirable. If it is less than 15 μm, the strength at the time of use becomes insufficient, and if it exceeds 300 μm, it is too hard as a first aid bandage and the texture is not preferable.

The film may be colorless and transparent, colored and transparent, or colored and non-transparent.

A first aid bandage is formed by using the film obtained by using the production method of the present invention as a substrate. As this forming method, for example, the following known arbitrary methods can be adopted.

An adhesive layer is provided on the surface of the film for first aid bandage. If necessary, the film surface is subjected to corona treatment or anchor coating, and then an adhesive is applied.

The above-mentioned pressure-sensitive adhesive layer may be provided on the entire surface of the film, and may be provided in the form of a thin line, a lattice, a spot, or a plane having a large number of small circles on which no pressure-sensitive adhesive is applied. It is also possible, and the state of this layer can be freely selected depending on the application. As the pressure-sensitive adhesive to be used, any of the pressure-sensitive adhesives usually used can be used and is not particularly limited, and examples thereof include various pressure-sensitive adhesives such as acrylic, rubber-based, silicone-based and vinyl ether-based pressure-sensitive adhesive.
These adhesives can be in any form such as solvent-based, emulsion-based, hot-melt-based and the like.

As a method of applying the adhesive to the film, the adhesive may be directly applied to the entire surface of the film, or the adhesive may be applied to the surface of the process paper (release paper) and superposed on the film. Alternatively, the adhesive layer may be transferred to the film side. If necessary, the film surface may be subjected to a corona treatment before the adhesive is applied. When performing corona treatment, set the film surface tension to 38 dyn.
/ Cm or more is preferable.

Gauze or the like is laminated on the surface having the pressure-sensitive adhesive layer of the thus-prepared first-aid bandage film, which is usually punched into a predetermined size and then packaged in an individual packaging material, and then further prescribed. Cut to size and get a first aid bandage. The obtained first-aid bandage can be a soft and stretchable bandage that does not press the affected area and has a good texture.

[0050]

The film for first-aid bandages obtained by the method for producing a film for first-aid bandages of the present invention contains substantially no plasticizer, has flexibility and stretchability, and is capable of relaxing stress when stretched. Since it is fast, it is possible to provide an emergency bandage that does not press the affected area and has a good texture.

The reason why the first-aid bandage film produced by the present invention has the above-mentioned excellent characteristics is presumed as follows.

It is considered that the polypropylene resin used in the present invention is alloyed by introducing a large amount of an amorphous polymer represented by ethylene-propylene copolymer into the polypropylene resin during the polymerization. To be
The use of titanium-based catalysts, which are very active and have a long life, appears to have enabled some manufacturers to make resins of this type. There are several kinds of copolymers having different molecular structures in the polymer obtained by such polymerization, and therefore it is considered that a characteristic morphology is developed in the alloy of the ordinary resin part such as polypropylene and these copolymer parts. . As a result, it is considered that the film for first aid bandage in the present invention exhibits physical properties very close to those of plasticized PVC.

By inflation-molding the above polypropylene-based resin under specific conditions, the molecules are slightly oriented in a state where residual strain is small, so that stretchability and stress relaxation property are maintained, and at the time of applying or re-adhesive bandages. It is possible to obtain a film having sufficient tensile strength, which does not extend even when pulled strongly.

Further, it is considered that heat shrinkage of the film can be suppressed by annealing this film at 70 to 150 ° C.

[0055]

EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited thereto.

In the following examples, tensile strength, stress relaxation, and heat shrinkage were tested by the methods described below.

Tensile strength: Specimen width 19 by a tensile tester
mm, the initial sample length (holding interval) of 100 mm, was pulled in the stretching direction at a pulling speed of 200 mm / min, and the tensile strength at elongations of 5%, 10%, and 50% was measured.

Stress relaxation: Specimen width 1 by a tensile tester
A film sample having a length of 9 mm and an initial sample length of 100 mm was pulled at a tensile speed of 200 mm / min in the stretching direction to an elongation of 10%, and then held for 5 seconds, and 1
The tensile strength after the minute was measured, and the ratio of residual stress was calculated by the following formula.

[0059]

[Equation 1]

Heat shrinkage: 100 m for a single film sample
Marked line of mx100mm is put and it is 70 ℃ in a gear oven.
After heating for 5 hours, the heat shrinkage was measured.

[0061]

[Equation 2]

Example 1 Weight average molecular weight 250,00
0, the elution amount at each temperature by the cross fractionation method is 0 ° C or more 1
67.0% by weight below 0 ° C, 1 above 10 ° C and below 70 ° C
7.9% by weight, above 70 ° C and below 95 ° C 3.2% by weight, 9
A polypropylene resin (manufactured by Tokuyama Soda Co., Ltd.) that is more than 5 ° C and 125 ° C or less at 10.5% by weight is blown with an inflation die 6 shown in Fig. 1 at an extrusion temperature of about 200 ° C, a draft ratio of 19.8, and a frost line height. Was extruded to have a diameter of 1.8 times the die diameter to form the film 2, and the film 2 was laminated on the process paper 1 through the heating laminating roll 7.
The formed film surface 21 was subjected to corona discharge treatment to obtain a laminated body of the film 2 for first aid bandage and the process paper 1 described above.
The thickness of this film 2 was 68 μm. The obtained laminate was wound up. Film 2 thus obtained
Was peeled from the process paper 1, and the tensile strength, stress relaxation, and heat shrinkage during stretching in the transverse (stretching) direction were measured. The results are shown in Table 1.

Next, a polyethylene layer is laminated on one side of the kraft paper, and a silicone release agent is applied to the surface of the polyethylene layer. An agent solution (natural rubber, polyterpene resin, polybutene, and 35% toluene solution of anti-aging agent) is applied and dried using a coating and drying winder so that the thickness after drying is 40 μm, and an adhesive Layer 3 was formed. Then, the corona-treated surface 21 of the laminate of the above-mentioned film 2 for first aid bandage and process paper 1 and the adhesive layer surface of the process paper having this adhesive layer 3 were laminated together. The process paper was peeled from the pressure-sensitive adhesive layer 3 (FIG. 3) and wound into a roll by a winder.

This roll of adhesive tape for plasters was cut into a 19 mm width using a slitter so that the film 2 and the process paper 1 would not be peeled off.
m). The obtained 19 mm wide tape bandage for adhesive bandages was processed by the processing device for emergency bandages shown in FIG. 4, and the emergency bandages were obtained.

This processing device is provided with a device for supplying auxiliary materials for a first-aid bandage of a predetermined width (gauze, release paper for replacement, individual packaging, etc.), and the above-mentioned tape for first-aid bandage applied to this device. When the anti-A is fed, the film 2 and the pressure-sensitive adhesive layer 3 are subjected to minute perforation processing 51. Then, on the upper surface of the adhesive layer 3, a thickness of 1 mm and a width of 17 mm
× Gauze 52 having a length of 25 mm is attached, and while the process paper 1 is peeled off, the release paper 53 forms the gauze 52 and the adhesive layer 3
Granted from above. The obtained laminate is punched 54 in a predetermined size (width 19 mm × length 75 mm, both ends having an arc shape with a radius of 12 mm), wrapped with an individual wrapping material 55, and cut 56.
Then, the first-aid bandage 57 as shown in FIG. 5 was obtained.

Example 2 Example 1 was repeated except that the polypropylene resin of Example 1 was used, the draft ratio was 26.2, and the frost line height was 6.0 times the die diameter.
A film for a first-aid bandage and a first-aid bandage were prepared by the same method. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 1.

(Comparative Example 1) Example 1 was repeated except that the polypropylene resin of Example 1 was used, the draft ratio was 4.6, and the frost line height was 1.8 times the die diameter. A film for a first-aid bandage and a first-aid bandage were prepared by the same method. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 1.

Comparative Example 2 Example 1 was repeated except that the polypropylene resin of Example 1 was used, the draft ratio was 42.0, and the frost line height was 1.8 times the die diameter.
A film for a first-aid bandage and a first-aid bandage were prepared by the same method. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 1.

Comparative Example 3 The polypropylene resin of Example 1 was used to perform inflation molding with a draft ratio of 19.8 and a frost line height of 0.8 times the die diameter. Then, the sample could not be obtained.

(Comparative Example 4) Example 1 was repeated except that the polypropylene resin of Example 1 was used, the draft ratio was 19.8, and the frost line height was 7.5 times the die diameter.
A film for a first-aid bandage and a first-aid bandage were prepared by the same method. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 1.

(Comparative Example 5) The molecular weight was 200,000, and the elution amount at each temperature by the cross fractionation method was 2.5% by weight at 0 ° C or more and 10 ° C or less and 16.2% by weight at more than 10 ° C and 70 ° C or less. 80.5% by weight below 70 ° C and below 95 ° C, 1 above 95 ° C
A polypropylene resin (manufactured by Highmont Co., Ltd.) that is 0.8% by weight at 25 ° C. or lower is used, except that the draft ratio is 19.8 and the frost line height is 1.8 times the die diameter.
A film for a first-aid bandage and a first-aid bandage were prepared in the same manner as in Example 1. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 1.

Examples 1 and 2 and Comparative Examples 1 to 5
Table 1 below shows the evaluation results of the first-aid bandage film and the first-aid bandage obtained in 1.

[0073]

[Table 1]

(Example 3) The polypropylene resin of Example 1 was extruded with an inflation die 6 shown in FIG. 2 at an extrusion temperature of about 200 ° C., a draft ratio of 19.8, and a frost line height of 1.8 as the die diameter. The film 2 was extruded so as to be doubled, and then the film 2 was annealed at an annealing temperature of 110 ° C. along the roll surface by the annealing device 8, and then laminated on the process paper 1 through the heating laminating roll 7. The subsequent steps for producing the first-aid bandage and the evaluation of the obtained first-aid bandage film were performed in the same manner as in Example 1. The results are shown in Table 2.

Example 4 The polypropylene resin of Example 1 was used, except that the draft ratio was 41.3, the frost line height was 1.8 times the die diameter, and the annealing temperature was 110 ° C. In the same manner as in Example 1, a film for a first-aid bandage and a first-aid bandage were prepared. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2.

(Comparative Example 6) Using the polypropylene resin of Example 1, except that the draft ratio was 4.6, the frost line height was 1.8 times the die diameter, and the annealing temperature was 110 ° C. In the same manner as in Example 1, a film for a first-aid bandage and a first-aid bandage were prepared. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2.

(Comparative Example 7) Using the polypropylene resin of Example 1, an attempt was made to carry out inflation molding with a draft ratio of 52.3 and a frost line height of 1.8 times the die diameter. Then, the sample could not be obtained.

(Comparative Example 8) Using the polypropylene resin of Example 1, except that the draft ratio was 19.8, the frost line height was 7.5 times the die diameter, and the annealing temperature was 110 ° C. In the same manner as in Example 1, a film for a first-aid bandage and a first-aid bandage were prepared. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2.

(Comparative Example 9) Using the polypropylene resin of Example 1, except that the draft ratio was 19.8, the frost line height was 1.8 times the die diameter, and the annealing temperature was 60 ° C. In the same manner as in Example 1, a film for a first-aid bandage and a first-aid bandage were prepared. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2.

(Comparative Example 10) Using the polypropylene resin of Example 1, the draft ratio was 19.8, the frost line height was 1.8 times the die diameter, and the annealing temperature was 155 ° C.
A film for a first-aid bandage and a first-aid bandage were prepared in the same manner as in Example 1, except that The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2.

Comparative Example 11 Using the polypropylene resin of Comparative Example 5, except that the draft ratio was 19.8, the frost line height was 1.8 times the die diameter, and the annealing temperature was 110 ° C. A film for a first-aid bandage and a first-aid bandage were prepared in the same manner as in Example 1. The tensile strength, stress relaxation, and heat shrinkability were evaluated as in Example 1. The results are shown in Table 2. Examples 3 and 4 and Comparative Examples 6 to
Table 2 below shows the evaluation results of the first-aid bandage film and the first-aid bandage obtained in No. 11.

[0082]

[Table 2]

[0083]

EFFECTS OF THE INVENTION According to the present invention, by using a specific polypropylene resin, a plasticizer is not substantially contained, it has flexibility and stretchability, and stress relaxation during stretching is fast and sufficient. It is possible to obtain a method for producing a film for first-aid bandages which has tensile strength, does not press the affected area, has a good texture, and is a substitute for the conventional plasticized PVC film.

[Brief description of drawings]

FIG. 1 shows a method for producing a film for a first-aid bandage according to the present invention,
It is a schematic diagram showing an example of manufacture by the inflation method.

FIG. 2 shows a method for producing a film for first aid bandages according to the present invention,
It is a schematic diagram showing an example of manufacture using an inflation method and an annealing device.

[Fig. 3] A film for emergency bandages laminated on process paper,
It is sectional drawing which shows the state which laminated | stacked the adhesive layer provided on the film.

FIG. 4 is a schematic view showing a manufacturing process of the first-aid bandage.

FIG. 5 is a plan view of an emergency adhesive bandage obtained by using the method for producing a film for emergency adhesive bandage of the present invention.

[Explanation of symbols]

 1 Process paper 11 Release treatment surface 2 Film 21 Corona treatment surface 3 Adhesive layer 52 Gauze 53 Release paper 57 First aid bandage

Claims (2)

[Claims] 1. A weight average molecular weight of 80,000 to 50.
It is a polypropylene-based resin in the range of 10,000, and the resin elution amount by the cross fractionation method at 0 ° C or higher and 10 ° C or lower is 45 to 80% by weight of the total polypropylene-based resin amount, and more than 10 ° C and 70 ° C or less. The amount of resin eluted at 5 to 35% by weight of the total polypropylene-based resin is above 70 ° C.
Resin elution amount below ℃ is 1 of total polypropylene resin amount
A polypropylene resin having a composition within a range of ˜30% by weight, and a resin elution amount at a temperature higher than 95 ° C. and 125 ° C. or lower is 5 to 35% by weight based on the total amount of the polypropylene resin, a draft ratio of 5 to 30, And a method for producing a film for a first-aid bandage, which comprises molding by an inflation method under the condition that the height of the frost line is 1 to 7 times the die diameter. 2. A weight average molecular weight of 80,000 to 50.
It is a polypropylene-based resin in the range of 10,000, and the resin elution amount by the cross fractionation method at 0 ° C or higher and 10 ° C or lower is 45 to 80% by weight of the total polypropylene-based resin amount, and more than 10 ° C and 70 ° C or less. The amount of resin eluted at 5 to 35% by weight of the total polypropylene-based resin is above 70 ° C.
Resin elution amount below ℃ is 1 of total polypropylene resin amount
A polypropylene resin having a composition within a range of ˜30 wt% and a resin elution amount in the range of more than 95 ° C. and 125 ° C. or less of 5 to 35 wt% of the total polypropylene resin amount, a draft ratio of 5 to 50, And frost line height 1
A method for producing a film for emergency plasters, which comprises molding by an inflation method under a condition of 7 to 7 times, and then annealing under a condition of an annealing temperature of 70 to 150 ° C.