JPH08196615A - First-aid adhesive plaster film - Google Patents

Abstract

PURPOSE: To provide a first-aid adhesive plaster film which does not substantially contain a plasticizer, has flexibility and expandability, and is difficult to be blocking, by providing a base constitution that a surface layer containing polyolefine resin is laminated on an inner layer containing a polypropylene resin. CONSTITUTION: This emergency adhesive plaster film has such a constitution that a surface layer containing polyolefine resin is laminated on an inner layer containing a polypropylene resin. Here, weight average molecular weight of the polypropylene resin is in the range of 80,000∼500,000 and an eluted amount of the polypropylene resin in each temperature range by means of a cross fractional method is 45∼80 weight % of total weight of the polypropylene resin at 10 deg.C or less and 5∼35 weight % at 95 deg.C over to 125 deg.C or less. Furthermore, the polyolefine resin is a copolymer of ethylene with an α-olefin of carbon number of 3 or more, and its density is in the range of 0.895∼0.925g/cm<3> , and DSC heating value is in the range of 55∼140J/g.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a film for first aid bandages. More specifically, it is a film for a first-aid bandage that is flexible and stretchable without substantially containing a plasticizer and is difficult to block even when stored for a long time,
The present invention relates to a film for a first-aid bandage that does not press the affected area and has a good texture.

[0002]

2. Description of the Related Art It is important that a film for a first aid bandage has excellent flexibility and stretchability, does not press the affected area, and has a good texture. As a resin suitable for film use that satisfies such characteristics, plasticized polyvinyl chloride (hereinafter abbreviated as plasticized PVC) can be mentioned. This plasticized PVC is generally film-formed by a calendar or the like and put to practical use. However, when a film is made from the plasticized PVC, the film generally contains a large amount of the plasticizer, so that the plasticizer migrates to the surface, resulting in poor adhesion between the film and the adhesive and migration of the plasticizer to the adhesive. This causes a problem such as a decrease in adhesive strength or a decrease in flexibility at low temperature. On the other hand, in recent years, environmental issues have become important,
Plasticized P that contains halogen and generates hydrogen chloride during combustion
There is a desire to stop the use of VC, and research into alternative materials for it is active.

Therefore, a flexible and stretchable polyolefin resin has been actively developed as a material replacing plasticized PVC. For example, JP-A-62-829
No. 67 discloses a blend of a hydrocarbon-based elastomer such as ethylene-propylene rubber or ethylene-propylene-diene terpolymer for imparting flexibility, and a polyolefin such as ethylene-vinyl acetate copolymer. A film for a first aid bandage is disclosed. However, in such a film, for example, flexibility and deformation recovery are not sufficient as compared with plasticized PVC. Further, in such an elastomer-containing film, when stored for a long time, there is a problem that a roll-shaped film original film is blocked.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and its object is to have flexibility and elasticity without containing a plasticizer,
It is an object of the present invention to provide a film for an emergency adhesive bandage which does not easily block even when it is stored for a long time, and which does not press the affected part and has a good texture.

[0005]

The film for first aid bandage of the present invention according to claim 1 has a constitution in which a surface layer containing a polyolefin resin is laminated on an inner layer containing a polypropylene resin. The weight average molecular weight of the resin is in the range of 80,000 to 500,000, and the elution amount of the polypropylene resin in each temperature range in the cross fractionation method is 10 with respect to the total weight of the polypropylene resin.
45-80% by weight below 10 ° C and 5 above 10 ° C below 70 ° C
45% by weight, 0 to 20% by weight at 70 ° C or higher and 95 ° C or lower, 9
It is 5 to 35% by weight at more than 5 ° C and 125 ° C or less, the polyolefin resin is a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, and the density of the polyolefin resin is 0.895 to 0. 0.925 g / cm ³ , and the DSC calorific value of the polyolefin resin is 55 to 1
It is characterized by being in the range of 40 J / g.

[0006] In the film for first aid bandage of the present invention according to claim 2, the polyolefin resin according to claim 1 has a ratio Mw / Mn of weight average molecular weight Mw to number average molecular weight Mn of 3
It is characterized in that it is the following, and that there is only one crystal melting peak temperature in the DSC analysis at 65 to 115 ° C.

The polypropylene resin used in the inner layer of the film for first aid bandage of the present invention is preferably propylene and / or a copolymer of propylene and α-olefin. This polypropylene resin is a copolymer having propylene and, if necessary, α-olefin as a component. As the α-olefin component, ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-hexene, 1-octene and the like are used.

The polypropylene resin is produced by, for example, 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 if necessary, an ethylene monomer and an α-olefin monomer. Thereby, a propylene homopolymer,
A propylene-ethylene copolymer, a propylene-α-olefin copolymer and the like can be obtained. Then, as a second step, a state containing a titanium compound catalyst and an aluminum compound catalyst, for example, a reaction liquid containing the homopolymer or copolymer, a propylene monomer, and optionally an ethylene monomer, an α-olefin A polypropylene resin is obtained by adding a monomer and copolymerizing. At this time, the components added in the second stage may be added in one stage or in two stages. That is, this polymerization method can be a multi-step polymerization of three or more steps. The polypropylene resin obtained by this multistep reaction is a propylene homopolymer, a propylene-ethylene copolymer, a propylene-α-olefin copolymer, or a propylene-polymer.
It can be an ethylene-α-olefin copolymer.

The polypropylene resin has a weight average molecular weight of 80,000 to 500,000, preferably 100,000 to 400,000. When the weight average molecular weight is less than 80,000, the resulting film has insufficient stretchability and strength. Weight average molecular weight is 50
If it exceeds 10,000, the obtained film cannot have sufficient flexibility.

The elution amount of the polypropylene resin in each temperature range in the cross fractionation method is 45 to 80% by weight, preferably 50 to 75% by weight at 10 ° C. or less based on the total weight of the polypropylene resin. 5 to 45% by weight, preferably 5 to 30% by weight at more than 10 ° C and 70 ° C or less, 7
0 to over 95 ° C and 0 to 20% by weight, preferably 0 to
10% by weight, 5 to 35% by weight above 95 ° C and 125 ° C or less,
It is preferably 5 to 30% by weight. When the elution amount at 10 ° C or lower is less than 45% by weight, the flexibility of the obtained film is insufficient, and when it exceeds 80% by weight, the strength of the obtained film is insufficient. If the amount eluted at more than 10 ° C and 70 ° C or less is less than 5% by weight, the flexibility of the obtained film is insufficient, and if it exceeds 45% by weight, the deformation recovery of the obtained film is insufficient. If the elution amount at more than 70 ° C and 95 ° C or less exceeds 20% by weight, the strength of the obtained film is insufficient. Elution volume is 5 above 95 ℃ and below 125 ℃
When it is less than wt%, the strength of the obtained film is insufficient, and when it exceeds 35 wt%, the flexibility of the obtained film is insufficient.

Further, the above-mentioned temperature is not higher than 10 ° C. and higher than 10 ° C. 70
Below ℃, above 70 ℃ to below 95 ℃, and above 95 ℃ to 125 ℃
The preferred ranges of the weight average molecular weight of the eluted resin in the following temperature ranges are 100,000 to 300,000 and 70,000 to 5, respectively.
They are 0,000, 50,000 to 500,000, and 50,000 to 500,000.

Here, the cross fractionation method is prepared in advance by cooling a solution in which a resin is completely dissolved in a solvent (o-dichlorobenzene in the present invention) at a constant rate (1 ° C./min). After forming a thin polymer layer on the surface of the inert simple substance, the temperature is raised continuously or stepwise, and the concentration of the resin component which is sequentially eluted is detected. Then, the composition distribution (crystallinity distribution) is measured from this concentration (temperature rising elution fractionation). At the same time, the molecular weight of each eluted component can be measured.

The polyolefin resin used in the surface layer of the film for first aid bandages of the present invention is a copolymer composed of a combination of ethylene and an α-olefin having 3 or more carbon atoms. Examples of the α-olefin having 3 or more carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene and 4
-Methyl-1-pentene, 1-hexene, 1-octene and the like are used.

The density of the polyolefin resin is 0.
895 to 0.925 g / cm³, Preferably 0.900
~ 0.915 g / cm³Is. Density is 0.895g /
cm ³Below, low molecular weight due to increased comonomer content
Tackiness appears on the surface of the film obtained by increasing the number of objects
It becomes easier to block. 0.925g / cm³Over
The resulting film does not cause blocking
However, the flexibility is insufficient and the surface tensile strength is high.
It is hard to use because it causes a tight feeling when used.

The calorific value of DSC of the above polyolefin resin is in the range of 55 to 140 J / g. Calorific value is 55J
If it is less than / g, the obtained film tends to block. When the calorific value exceeds 140 J / g, the flexibility of the obtained film is insufficient and a feeling of tension is generated when the film is used as a bandage.

That is, the density is 0.895 to 0.925 g /
By using a polyolefin-based resin having a cm ³ and a DSC calorific value of 55 to 140 J / g, the content of a low molecular weight substance is extremely low as compared with a conventional polyolefin-based resin having the same density, and the blocking resistance is excellent. It is effective for preventing a decrease in the adhesive strength due to the transfer of low molecular weight substances to the adhesive.

The polyolefin resin used in the film for emergency plasters according to claim 2 is a single catalyst such as a metallocene catalyst (Kaminsky catalyst) or a vanadium catalyst as a catalyst for polymerizing ethylene and α-olefin. The one having a chemical structure having an active site (single-site catalyst) is used. As a result, a polyolefin resin having only one crystal melting peak in DSC analysis can be obtained. This product has a much lower content of low molecular weight substances as compared with a polyolefin resin produced using a conventional catalyst.

Conventional linear low density polyethylene (LLD
Polymerization catalyst used in the production of PE (Ziegler
In the case of Natta catalysts and the like), the polymerized polymer was a mixture of a plurality of types of composition components because it has a plurality of active sites in one molecule. For use in adhesive plasters, if the content of α-olefin, which is a comonomer, is increased for softening, an increase in low molecular weight substances cannot be avoided with conventional catalysts, causing blocking or low molecular weight substances. There was a possibility of causing a decrease in adhesive strength due to transfer to an adhesive. The invention described in claim 2 improves on this point.

The film for first aid bandages of the present invention is obtained by laminating an inner layer containing the polypropylene resin and a surface layer containing the polyolefin resin. The inner layer and the surface layer are formed into a film having a predetermined thickness by a T-die method, an inflation method or the like. The film for first aid bandage of the present invention can be obtained by forming the above-mentioned inner layer and the above-mentioned surface layer as a laminated film by co-extrusion, or by extruding each single-layer film and laminating by heat lamination.

The inner layer and the surface layer each have 2
More than one layer may be laminated. That is, the film for first aid bandages of the present invention may be a laminate having three or more layers.

The layer thickness ratio between the inner layer and the surface layer in the film for first aid bandage of the present invention is preferably 1: 1 to 15: 1, and more preferably 5: 1 to 9: 1. When the layer thickness ratio is less than 1: 1, the flexibility of the obtained film is insufficient and the tensile strength is insufficient. If it exceeds 15: 1,
Since the surface layer becomes too thin, the film formation becomes difficult, the stress relaxation property is lost, and the preferable physical properties as a bandage are lost.

The thickness of the film for first aid bandage of the present invention is
15 to 300 μm is preferable, and 50 is more preferable.
˜80 μm. When the film thickness is less than 15 μm,
The strength during practical use is insufficient. If it exceeds 300 μm,
The flexibility in practical use is insufficient and the desired texture cannot be obtained.

The first-aid bandage film of the present invention may be colorless and transparent, colored and transparent, or colored and opaque. Further, the first-aid bandage film of the present invention can be given a high-class feeling by performing embossing such as silk.

A first-aid bandage using the film for a first-aid bandage of the present invention can be manufactured by the following procedure. The first-aid bandage film of the present invention can be printed if desired, and in that case, the printed surface is subjected to corona treatment under the condition that the surface wettability immediately before printing is 38 dyn / cm or more. Print by a direct printing method or a transfer printing method. Next, the surface of the printed film for the first-aid adhesive bandage coated with the adhesive has a surface wettability of 38 dyn /
Corona treatment is performed so that the thickness can be secured to cm or more, or an anchor coat is applied and then an adhesive is applied.

As the pressure-sensitive adhesive, pressure-sensitive adhesives such as acrylic type, rubber type and SIS type can be used. The film for bandages is perforated and gauze or the like is attached. Furthermore, after stacking a protective release paper on the gauze and punching individual wrapping paper into a predetermined size to form a product, a first-aid bandage as a product can be obtained.

[0026]

In the film for first aid bandage according to the first aspect, the polypropylene resin is excellent in flexibility because it forms a film having low tensile strength due to the molecular weight characteristics (molecular weight distribution) defined by the cross fractionation method. And, the polyolefin-based resin, in the range characterized by the density and DSC,
The resulting film is less sticky and has excellent blocking properties. Therefore, the first-aid bandage film of the present invention which has a flexible film as an inner layer and a film having less stickiness as a surface layer has both excellent flexibility and excellent blocking property. Further, such a film for a first aid bandage of the present invention has a small change in mechanical properties in a practical temperature range. Therefore, the first-aid bandage using the film for a first-aid bandage of the present invention has high reliability as a product.

On the other hand, the film for the first-aid bandage of the present invention containing substantially no plasticizer has a poor adhesion between the film and the adhesive when the plasticizer is used, or the adhesive strength due to the transfer of the plasticizer to the adhesive. It is possible to solve the problem such as a decrease in power consumption.
In addition, the halogen-free film for first-aid bandages of the present invention does not generate toxic gas such as hydrogen chloride at the time of burning, and is a well-suited one for environmental problems in recent years. Thus, the film for a first aid bandage of the present invention can solve the problems in plasticized PVC.

The film for emergency bandage according to claim 2 is
A polyolefin resin produced by using a catalyst having a chemical structure having a single active site in one molecule, having one crystal melting peak in DSC analysis, and having a crystal melting peak temperature in the range of 65 to 115 ° C. It is laminated as a surface layer. As a result, the content of the low molecular weight substance is extremely low, which does not cause blocking or cause a decrease in the adhesive force due to the transfer of the low molecular weight substance to the pressure-sensitive adhesive.

[0029]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. The evaluation items in the examples of the present invention are as follows.

(1) Tensile strength and flexibility during extension Width (MD: longitudinal direction) 19 mm, length (TD: lateral direction) 1
A sample of 00 mm was prepared and pulled by a tensile tester (Tensilon UCT-500 manufactured by Orientec Co., Ltd.) at a chuck interval of 50 mm and a pulling speed of 100 mm / min.
The tensile strength was measured when the elongation was 10%, and the flexibility was evaluated according to the following criteria. ◯: Good Tensile strength is 200 to 450 gf / 1
9 mm ×: Poor Tensile strength less than 200 gf / 19 mm or more than 450 gf / 19 mm

(2) Peeling force and blocking property One surface of the film and the other surface are overlapped, and 40
After pressure storage at 10 ° C. and 10 kg / cm ² for 1 month, the peeling force was measured when slitting in a width of 50 mm and peeling at a pulling speed of 300 mm / min, and the blocking property was evaluated according to the following criteria. ◯: Good peel force is less than 50 gf / 50 mm Δ: Fairly good Peel force is 50 to 100 gf / 50 m
m x: Poor The peeling force exceeds 100 gf / 50 mm.

(3) Comprehensive Evaluation Using the above evaluations (1) and (2), a comprehensive evaluation was made according to the following criteria. ◯: Good Both of the evaluation results of (1) and (2) are ◯: Poor In any of the evaluation results of (1) and (2) above, there is × or Δ.

Example 1 As a polyolefin resin for the surface layer, a copolymer of ethylene and 4-methyl-1-pentene having a density of 0.910 g / cm ³ and a DSC calorific value of 90 J / g (Mitsui Petrochemical Co., Ltd. Made by Ult-Zex 102
0L) as the polypropylene resin for the inner layer, the molecular weight is 240,000, and the elution amount in each temperature range by the cross fractionation method is 55.4% by weight with respect to the total weight at 10 ° C or less and more than 10 ° C. 31.0% by weight below ℃, more than 70 ℃ 9
A polypropylene resin (Cataloy, manufactured by Highmont Co., Ltd.), which is 0.7% by weight at 5 ° C. or less and 12.9% by weight at more than 95 ° C. and 125 ° C. or less, was used. A laminate film having a surface layer thickness of 10 μm and an inner layer thickness of 60 μm was formed by co-extruding the polyolefin resin and the polypropylene resin with a T-die to obtain a film for a first-aid bandage having a total thickness of 70 μm and having a two-layer structure.

(Example 2) As a polyolefin resin for the surface layer, a copolymer of ethylene and 1-octene having a density of 0.907 g / cm ³ and a DSC calorific value of 85 J / g (manufactured by Idemitsu Petrochemical Co., Ltd., Moretech VO398CN). ),
The polypropylene resin used in Example 1 was used as the polypropylene resin for the inner layer. The polyolefin resin and the polypropylene resin were each subjected to inflation coextrusion to have a surface layer thickness of 5 μm and an inner layer thickness of 6
Forming a laminated film having a total thickness of 0 μm and a thickness of 70 μm,
A three-layer structure first-aid bandage film having surface layers on both sides of the inner layer was obtained.

Example 3 As a polyolefin resin for the surface layer, a copolymer of ethylene and 1-butene having a density of 0.900 g / cm ³ and a DSC calorific value of 75 J / g (manufactured by Sumitomo Chemical Co., Ltd., Excellen VL- In the same manner as in Example 2 except that 200) was used, a three-layer structure first-aid bandage having a surface layer thickness of 5 μm, an inner layer thickness of 60 μm, and a total thickness of 70 μm and having surface layers on both sides of the inner layer. I got a film.

Example 4 As a polyolefin resin for the surface layer, the density was 0.910 g / cm ³ , and the DSC calorific value was 9
Copolymer of ethylene and 1-octene having 8 J / g, Mw / Mn of 2.3, and a crystal melting peak temperature of 106 ° C. (manufactured by Dow, trade name “Affinity PL1840”)
As a polypropylene resin for the inner layer
50,000, the elution amount in each temperature range by the cross fractionation method is 56.4% by weight at 10 ° C or less based on the total weight, and more than 10 ° C is 7%.
18.4% by weight below 0 ° C, 1 above 70 ° C and below 95 ° C
6.8 wt% and 8.41 above 95 ° C and below 125 ° C
Polypropylene resin (wt%, manufactured by Highmont,
The product name “Cataloy”) was used. The above polyolefin resin and the above polypropylene resin were each subjected to inflation coextrusion to have a surface layer thickness of 5 μm and an inner layer thickness of 6
Forming a laminated film having a total thickness of 0 μm and a thickness of 70 μm,
A three-layer structure first-aid bandage film having surface layers on both sides of the inner layer was obtained.

Example 5 As a polyolefin resin for the surface layer, a density of 0.905 g / cm ³ and a calorific value of DSC of 9
A copolymer of ethylene and 1-octene (0J / g, Mw / Mn of 2.2, and a crystal melting peak temperature of 92 ° C., manufactured by Sumitomo Chemical Co., Ltd., trade name “SPO NO352”)
Using the same polypropylene-based resin as that used in Example 4 as the inner layer polypropylene-based resin, a layer having a total thickness of 70 μm, each having a surface layer thickness of 5 μm and an inner layer thickness of 60 μm, was formed by inflation coextrusion in the same manner as in Example 4. The film was molded to obtain a three-layer structure first-aid bandage film having surface layers on both sides of the inner layer.

(Comparative Example 1) As a polyolefin resin for the surface layer, ethylene-α-olefin copolymer having a density of 0.890 g / cm ³ and a DSC calorific value of 2 J / g (manufactured by Mitsui Petrochemical Co., Ltd., Tuffmer P-0280). In the same manner as in Example 1 except that (1) was used, a film for an emergency adhesive bandage having a two-layer structure having a surface layer thickness of 10 μm, an inner layer thickness of 60 μm, and a total thickness of 70 μm was obtained.

(Comparative Example 2) As a polyolefin resin for the surface layer, a copolymer of 4-methyl-1-pentene having a density of 0.935 g / cm ³ and a DSC calorific value of 160 J / g (manufactured by Mitsui Petrochemical Co., Ltd., Ultzex). 3520L) was used in the same manner as in Example 2 except that the surface layer thickness was 5 μm, the inner layer thickness was 60 μm, and the total thickness was 70 μm.
A three-layer structure first-aid bandage film having surface layers on both sides of the inner layer was obtained.

Comparative Example 3 As a polyolefin resin for the surface layer, a copolymer of ethylene and 1-octene having a density of 0.907 g / cm ³ and a DSC calorific value of 85 J / g (manufactured by Idemitsu Petrochemical Co., Ltd., Moatech VO398CN). ),
Also, as a polypropylene resin for the inner layer, a molecular weight of 27
And the elution amount in each temperature range by the cross fractionation method was 40.3% by weight at 10 ° C. or less based on the total weight, 10
19.2% by weight above 70 ° C and below 70 ° C, 10.0% by weight above 70 ° C and below 95 ° C, and 3 above 95 ° C and below 125 ° C
A 0.5 wt% polypropylene resin (Cataloy, manufactured by Highmont Co., Ltd.) was used. The polyolefin resin and the polypropylene resin are formed into a laminated film by inflation coextrusion, and the surface layer has a thickness of 5 μm each.
m, the inner layer thickness was 60 μm, the total thickness was 70 μm, and a three-layer structure first-aid bandage film having surface layers on both sides of the inner layer was obtained.

The films for first aid bandages of Examples 1 to 5 and Comparative Examples 1 to 3 were evaluated according to the evaluation items (1) and (2). Table 1 shows the results.

[0042]

[Table 1]

As can be seen from Table 1, the first-aid bandage film of the present invention is excellent in both flexibility and blocking property.

[0044]

EFFECTS OF THE INVENTION According to the film for first-aid bandages of the present invention as set forth in claim 1, the first-aid bandages are flexible and stretchable without substantially containing a plasticizer and are hard to block even when stored for a long time. Film is provided. further,
The film for first aid bandage of the present invention does not press the affected area,
It is a film for first aid bandages that has a good texture.

According to the first-aid bandage film of the present invention as defined in claim 2, in addition to the effect of the first-aid bandage film according to the first aspect, it may cause blocking or transfer of a low molecular weight substance to an adhesive. The effect of not lowering the adhesive strength is more remarkable.

Claims (2)

[Claims] 1. A structure in which a surface layer containing a polyolefin resin is laminated on an inner layer containing a polypropylene resin, and the weight average molecular weight of the polypropylene resin is in the range of 80,000 to 500,000. The elution amount of the polypropylene-based resin in each temperature range in the cross fractionation method is 45 to 80% by weight at 10 ° C. or less based on the total weight of the polypropylene-based resin, and 5 to 45 at 10 ° C. or more and 70 ° C. or less.
% By weight, 0 to 20% by weight below 70 ° C. and 95 ° C., 95 ° C.
It is 5 to 35% by weight at a temperature of not more than 125 ° C., the polyolefin resin is a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, and the density of the polyolefin resin is 0.895 to 0. 925 g / cm ³ , and
DSF calorific value of the polyolefin resin is 55 to 140
A film for a first aid bandage, which is in the range of J / g. 2. The polyolefin resin has a ratio Mw / Mn of a weight average molecular weight Mw and a number average molecular weight Mn of 3 or less, and has only one crystal melting peak temperature at 65 to 115 ° C. in DSC analysis. The film for a first aid bandage according to claim 1, wherein