JPH10234838A - Film for affixing base - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film for affixing base which is excellent in flexibility, stretchability and chemical resistance, and does not generate environmental problems. SOLUTION: In the case of a three layer structure, this film 11 for affixing base is a multi-layer film of a three layer structure wherein, e.g. a first layer 12 which is an internal layer, a second layer 13 which is an intermediate layer, and a third layer 14 which is an external layer, are laminated. The resin of the second layer 13 comprises an ethylene. α-olefin copolymer, and this copolymer has the following characteristics of (a-d): (a) The density is 0.850-0.935g/ml. (b) MI is 0.3-15.0g/10min, (c) Mw/Mn=2.0-5.0, and (d) Tm<=125 deg.C. Also, the resin for the first layer 12 and the third layer 14 comprises a polyolefine based polymer. Also, in the case of a two layer structure, one of the layers has the previously mentioned characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a film for an adhesive substrate, and can be used as a film for a plaster-based haptic substrate, a film for a protective tape for protecting a wound, and the like.

[0002]

BACKGROUND ART Problems to be solved by the invention
The plaster-based film for the hap base material and the film for the protective tape for protecting the wound are required to have appropriate flexibility in order to maintain the adhesion to the skin. In addition, when applied to joints such as elbows, appropriate elasticity is also required so as not to impair mobility. Conventionally, as a resin film having such properties, a polyvinyl chloride film has been generally used, but the polyvinyl chloride film is inferior in chemical resistance and generates harmful gas when incinerated and disposed. There was also the problem of environmental pollution.

[0003] For this reason, instead of polyvinyl chloride, polyester-based elastomers that do not have a risk of generating chlorine gas,
Use of a film made of a polyamide-based elastomer, a polyurethane-based elastomer, a polyolefin-based elastomer, or a polystyrene-based elastomer has been proposed (see JP-A-8-206151). However, these elastomers generally have a drawback of poor chemical resistance.

Accordingly, an object of the present invention is to provide a film for an adhesive substrate which is excellent in flexibility, stretchability and chemical resistance and does not cause environmental problems.

[0005]

Means for Solving the Problems A first invention of the present invention is a film for an adhesive substrate having an intermediate layer, wherein the film for an adhesive substrate has an intermediate layer. It is composed of an α-olefin copolymer, and this copolymer has the following characteristics (ad).

Specific examples of the α-olefin include linear monoolefins such as propylene, 1-butene, 1-hexene, 1-octene, 1-nonene, and the like.
Branched-chain monoolefins such as -methylbutene-1, 3-methylpentene-1, and 4-methylpentene-1, and monoolefins substituted with an aromatic nucleus such as styrene.

(A) The density is 0.850 to 0.935 g / ml. When the density is less than 0.850 g / ml, the film strength is significantly reduced. On the other hand, when the density is higher than 0.935 g / ml, the film lacks flexibility and becomes poor in elasticity. This density can be measured according to JIS K-6760.

(B) MI (melt index) of 0.3 to 15.0 g / 10
Minutes. If the MI is less than 0.3 g / 10 minutes, the efficiency of extruding the resin from the extruder during film production will be poor. On the other hand, when it is more than 15.0 g / 10 minutes, the molding stability in inflation molding is lacking. This MI
Can be measured in accordance with ASTM D-1238 (190 ° C./2.16 kg).

(C) Mw / Mn = 2.0-5.0. If the molecular weight distribution represented by Mw / Mn is smaller than 2.0, the melt tension becomes small and the film formation becomes unstable. Further, when Mw / Mn is larger than 5.0, the time required for generating burns and sticking to the die during production is shortened, resulting in poor productivity. This Mw / Mn is preferably set to 2.0 to 3.0. This molecular weight distribution can be determined using a measuring instrument in which a differential viscometer is connected to a GPC (gel permeation chromatograph) measuring instrument. The molecular weight distribution is determined from the obtained absolute molecular weights (Mw and Mn).

(D) Tm ≦ 125 ° C. When the Tm (melting point) exceeds 125 ° C., the film becomes stiff and has poor elasticity. Preferably, 115 ° C
It is as follows. This Tm can be measured by a differential scanning calorimeter (DSC).

[0011] A film for an adhesive substrate according to a second invention of the present invention is characterized in that, in the first invention, the intermediate layer has the following property (e). (E) The molecular weight dependence width of the number of branches is 0 to 5/1000 carbon. The molecular weight dependence width of the number of branches can be determined using, for example, a GPC measuring device and an FTIR (Fourier transform infrared spectroscopy) measuring device for measuring the degree of branching. Specific measurement conditions for GPC include, for example, using two columns, a sample amount of 5 mg / ml, a temperature of 135 ° C., a flow rate of 1 ml / min, and a trichlorobenzene (TCB) solvent. The molecular weight distribution determined under these measurement conditions is divided into ten, and the average branch number of each fraction determined by FTIR, that is, the difference between the maximum value and the minimum value of the branch number for each molecular weight is defined as the width of the molecular weight dependency (however, , Divided area is 4
% Or less is cut.

The width of the molecular weight dependence of the number of branches of the ethylene / α-olefin copolymer is determined by the maximum number of branches and the minimum number of branches per 1,000 carbon atoms of the copolymer in all molecular weight fractions. The difference means 0-5. That is,
Regardless of the molecular weight fraction (whether a high molecular weight fraction or a low molecular weight fraction) is taken, it means that there is no great difference in the number of branches of the copolymer in the fraction. This molecular weight dependence width is 5
When the ratio of the low-branching component is increased beyond the range, the crystalline component is increased and the elasticity is deteriorated.

[0013] A film for an adhesive substrate according to a third invention of the present invention is characterized in that, in the first or second invention, the intermediate layer has the following property (f). (F) I ₁₀ / I ₂ ≧ 5.63 and Mw / Mn ≦ (I ₁₀ /
I ₂₎ -4.63. The above I ₁₀ is ASTM D-1238 (190 ° C./10 kg)
Based on measurement of melt index based on Said I
₂ is based on measurement of a melt index based on ASTM D-1238 (190 ° C./2.16 kg).

I ₁₀ / I ₂ indicates the degree of long branches, the higher the value, the more long branches in the resin. I ₁₀ / I ₂ is preferably 7 or more, more preferably 8 or more. I ₁₀ / I ₂ ≧ 5.63 and Mw /
By setting Mn ≦ (I ₁₀ / I ₂ ) −4.63, the molding stability can be improved.

[0015] The film for an adhesive substrate according to the fourth invention of the present invention, in any one of the first to third inventions, has an inner layer and an outer layer with the intermediate layer interposed therebetween. It is characterized by comprising a thermoplastic resin. The non-halogen thermoplastic resin includes polyethylene (LDPE, L-
LDPE, HDPE), polypropylene (homo, block, random), ethylene-α-olefin copolymer, ethylene-
Examples include vinyl acetate copolymer (EVA), ionomer resin, ethylene-methyl methacrylate copolymer (EMMA), ethylene-vinyl alcohol copolymer (EVOH), and silicone resin.

[0016] The film for an adhesive substrate according to the fifth invention of the present invention is the film according to any one of the first to fourth inventions, wherein the thickness of the intermediate layer is 10 to 95% with respect to all layers. Features. If the thickness of the intermediate layer is less than 10% with respect to all layers, the elasticity will not be exhibited. Conversely, if it is greater than 95% of the total layer, the thickness of the outer layer will not be sufficient, and the layer will lack chemical resistance during elongation. The film for an adhesive substrate of the present invention may include an intermediate layer having the above properties as the intermediate layer, and the number of layers is arbitrary as long as it is three or more.

The ethylene / α-olefin copolymer can be synthesized by various methods. For this synthesis, for example, a single-site catalyst (see JP-A-5-331324) can be used. The single-site catalyst includes, for example, a transition metal (titanium, zirconium, chromium, etc.) compound, a compound which reacts with the transition metal compound to form an ionic complex, a catalyst containing organoaluminum as a main component, and a periodic table. And transition metal compounds containing transition metals selected from IVB.

Further, a metal coordination complex containing a delocalized π bond substituted with a group that induces a constraint, a metal belonging to Group 3 to Group 10 or a lanthanide series of the periodic table, and an activating cocatalyst are provided. Can also be used.
6-306121). The complex includes an amidosilane compound, an amidoalkanediyl compound, and the like. Examples of the activating cocatalyst include aluminoxane having a high polymerization degree and a low polymerization degree, and methylaluminoxane is particularly preferable.

As the copolymerization method, there can be used ordinary slurry copolymerization method, gas-phase copolymerization method, bulk copolymerization method, solution copolymerization method, suspension copolymerization method and the like. The copolymerization temperature is generally -100 to 250C, preferably -50 to 200C, more preferably 0 to 130C.

The resin constituting the multilayer film according to the present invention may contain appropriate additives which are generally used. Examples of such additives include stabilizers such as antiblocking agents, lubricants, antioxidants, and ultraviolet absorbers, antistatic agents, flame retardants, inorganic and organic fillers, dyes, pigments, and the like. it can.

The sixth invention of the present invention is a film for an adhesive substrate having a two-layer structure, wherein one layer is made of an ethylene / α-olefin copolymer, and this copolymer has the following properties (a To d). (A) a density of 0.850 to 0.935 g / ml, and (b) an MI of 0.3 to 15.
0 g / 10 min, (c) Mw / Mn = 2.0-5.0, (d) Tm ≦ 1
25 ° C. The description of these characteristics is as described in the first invention.

The film for an adhesive substrate according to the seventh invention of the present invention is characterized in that, in the sixth invention, the one layer has the following property (e). (E) The molecular weight dependence width of the number of branches is 0 to 5/1000 carbon. The description of this characteristic is as described in the second invention.

The film for an adhesive substrate according to the eighth invention of the present invention is characterized in that, in the sixth or seventh invention, the one layer has the following property (f). (F) I ₁₀ / I ₂ ≧ 5.63 and Mw / Mn ≦ (I ₁₀ /
I ₂₎ -4.63. The description of this characteristic is as described in the third invention.

A ninth aspect of the present invention provides a film for an adhesive substrate according to any one of the sixth to eighth aspects, wherein the other layer is made of a non-halogen thermoplastic resin. The description of the non-halogen thermoplastic resin is as described in the fourth invention.

[0025] In the film for an adhesive substrate according to the tenth aspect of the present invention, in any of the sixth to ninth aspects, the thickness of the one layer is 10 to 90% with respect to all layers. It is characterized by. The reason for limiting the range is the same as the reason for limiting in the fifth invention.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] As shown in FIG. 1, a film 11 for an adhesive substrate according to the present embodiment comprises a first layer 12 serving as an inner layer, a second layer 13 serving as an intermediate layer, and a third layer 14 serving as an outer layer. Is a multilayer film having a three-layer structure in which is laminated. The resin of the second layer 13 is ethylene • α synthesized using a single-site catalyst.
-An olefin copolymer, which has the following characteristics a to e.

(A) a density of 0.850 to 0.935 g / ml, (b) M
I is 0.3 to 15.0 g / 10 min, (c) Mw / Mn = 2.0 to 5.0,
(D) Tm ≦ 125 ° C., (e) The molecular weight dependence width of the number of branches is 0 to 5/1000 carbon.

The resin of the first layer 12 and the third layer 14 is made of a polyolefin polymer. Then, these first layers 12
The thickness of the second layer 13 with respect to the entire thickness of the third layer 14 is 10 to
95%.

[Second Embodiment] As shown in FIG. 2, a film 21 for an adhesive substrate according to the present embodiment comprises a first layer 22 as one layer and a second layer 23 as the other layer. This is a film having a two-layer structure. The first layer 22 is made of an ethylene / α-olefin copolymer having the same a to e characteristics as those of the first embodiment. The resin of the second layer 23 is made of a polyolefin polymer. The first layer 22 and the second layer 22
The thickness of the first layer 22 with respect to the total thickness of the layer 23 is 10 to 90%.

[0030]

【Example】

[Examples 1 to 10] In the first embodiment, the first layer 12
The resin type of the third layer 14 shown in Table 1 below was used, and the discharge rate was 30 kg / hr and the molding temperature was 180 by a multilayer molding machine having three extruders having a diameter of 40 mm and a three-layer die having a diameter of 100 mm.
The film was formed under the conditions of 200 ° C. to obtain a film 11 (75 μm in thickness) for an adhesive substrate according to each example. Table 1 also shows the density, MI, Mw / Mn, Tm, etc. of the resin used.

[Comparative Examples 1 to 6] In the same manner as in the above Examples, films for the adhesive base material according to Comparative Examples were prepared using the resins shown in Table 2 as the resin types of the first to third layers. .

[0032]

[Table 1]

[0033]

[Table 2]

[Evaluation of Properties] In order to evaluate the film performance of the films for Examples 1 to 10, Comparative Examples 1 to 6 and the current film for a pasting substrate, the recovery rate, modulus, and weight after dipping in the Mittel solution were evaluated. The rate of increase and the rate of weight increase after immersion in the liquid paraffin plasticizer were measured, and the film formation was also evaluated. In addition, comprehensive evaluation was also performed based on the total score of the measurement results of each item. Tables 3 and 4 show the results.

The recovery rate was measured as follows: width 15 mm × length 150 mm
After grabbing the strip sample and stretching it 1.5 times with a width of 100 mm,
The measurement was performed by determining the difference (L) in the length before and after the extension of the extension portion 3 minutes after opening. The recovery rate (%) is (100-L)
/ 100 × 100. This measurement was performed in the direction of extrusion (MD) of the sample film and the direction (T
D). The score of the recovery rate was 5 points for 90% or more, 3 points for less than 90% and 80% or more, and 0 points for less than 80%. When the recovery rate is 70% or more, the stretchability is good. It is preferably at least 80%, more preferably at least 90%.

The modulus was measured as follows: width 20 mm, length 15
100mm grip width, 300m pulling speed for 0mm strip sample
/ min. This measurement was performed on the sample films at 10% elongation and 50% elongation, and the MD and TD
, Respectively. The rating of this modulus is
At 10% elongation, 3 points for 300 g / 20 mm or less and 0 points for 300 g / 20 mm or more. This modulus is preferably 400 g / 20 mm or less at 10% elongation, and 1000 g at 50% elongation.
/ 20 mm or less is preferable.

The weight increase rate after the immersion of the Mittel solution and the liquid paraffin plasticizer was measured in the following manner.
That is, a test film (3 cm × 3 cm) is immersed in a Mittel solution or a liquid paraffin plasticizer at room temperature for 24 hours, and then the film surface is washed with ethanol and dried at room temperature. Then, the change in weight before and after the impregnation is measured to determine the amount of dissolution or adsorption. (The above-mentioned Mittel solution is a solution in which glycol salicylate and L-menthol are dissolved at a ratio of 50 parts by weight / 50 parts by weight.
3 points when exceeding 10%, and -10 points when exceeding 10.

The change in weight due to the immersion of the Mittel solution is as follows:
5% or less is preferable. The change in weight due to the immersion of the liquid paraffin plasticizer is preferably 20% or less, more preferably 10% or less. Regarding the moldability of the film, bubble stability during inflation molding was evaluated. As to the evaluation of the moldability, the bubble was rated as stable (○) at 5 points, slightly unstable (△) at 3 points, and unstable at −10 points.

The evaluation criteria for the comprehensive evaluation are as follows. ○: Total score of 20 points or more, Δ: Total score of less than 20 points, 10 points or more, ×: Total score of less than 10 points.

[0040]

[Table 3]

[0041]

[Table 4]

As shown in Table 3, according to Examples 1 to 10, the film 11 for the adhesive substrate has a three-layer structure of the first layer 12 to the third layer 14, and the second layer 13 as the intermediate layer has a three-layer structure. It can be seen that, because of having the properties according to the present invention, the recovery rate and the modulus are good, and the stretchability and flexibility are excellent. In addition, the film 11 for an adhesive substrate in each of the examples has a small rate of weight increase after dipping in a Mittel solution or a liquid paraffin-based plasticizer, and has good chemical resistance. Also, bubble stability during inflation molding was excellent. Furthermore, since the film 11 for an adhesive substrate of each example is made of a non-halogen thermoplastic resin, there is no danger of generating a harmful gas even when incinerated and discarded,
The problem of environmental pollution does not arise.

On the other hand, from Table 4, according to the film for a three-layered laminated base material according to Comparative Example 1, the resin of the second layer is composed of an ethylene / α-olefin copolymer.
Since the thickness ratio of the second layer was smaller than the range of the present invention, the recovery rate was low and the elasticity was poor. According to the film for an adhesive substrate according to Comparative Example 2, the resin of the second layer is ethylene-α-
Although the olefin copolymer was used, the thickness ratio of the second layer was larger than the range of the present invention, and the thickness of the outer layer was thin. Further, the rate of weight increase after immersion in the liquid paraffin plasticizer was high, and the chemical resistance was poor.

According to the film for an adhesive substrate according to Comparative Example 3, the resin of the second layer is composed of an ethylene / α-olefin copolymer, but the branch number dependence width falls within the range of the present invention. Beyond that, the modulus was too large and lacked flexibility. According to the film for a pasting substrate of Comparative Example 4, the second
Since the resin of the layer was made of ethylene-propylene rubber (EPR), the modulus was low, the flexibility was low, and the strength was insufficient. In addition, bubbles were unstable during inflation molding.

According to the film for an adhesive substrate of Comparative Example 5,
Since the resin of the second layer was made of ethylene-propylene-diene copolymer (EPDM), many gels were generated in the film. In addition, bubbles were unstable during inflation molding. According to the film for an adhesive substrate of Comparative Example 6, since the resin of the second layer was made of styrene-butadiene-block copolymer (SBS), delamination was caused by repeated elongation. According to the current film, since it is a vinyl chloride-based film, it has a plasticizer, and the plasticizer elutes into the Mittel solution. Therefore, the weight loss after immersion in the Mittel solution is large, and the chemical resistance is poor.

[Examples 11 to 14] In the second embodiment, as shown in Table 5 below, resin types of the first layer 22 and the second layer 23 were used, and two extruders having a diameter of 40 mm and a diameter of 100 mm were used. With a multilayer molding machine having a two-layer die, the discharge rate is 30 kg / hr,
The film was formed at a molding temperature of 180 to 200 ° C. to obtain a film 21 (75 μm in thickness) for an adhesive substrate according to each example. Table 5 also shows the density, MI, Mw / Mn, Tm, and the like of the resin used.

[Comparative Examples 7 to 10] In the same manner as in the above examples, the films for the adhesive base materials according to the respective comparative examples were produced using the resins shown in Table 6 as the resin types of the first and second layers. .

[0048]

[Table 5]

[0049]

[Table 6]

[Evaluation of Properties] The films of Examples 11 to 14 and Comparative Examples 7 to 10 were applied to the films for the adhesive substrates described in Example 1 above.
The film performance was evaluated as in # 10. Tables 7 and 8 show the results.

[0051]

[Table 7]

[0052]

[Table 8]

As shown in Table 7, according to Examples 11 to 14, the film 21 for the adhesive substrate has a two-layer structure of the first layer 22 and the second layer 23, and the second layer 23 according to the present invention. It can be seen that, because of the properties, the recovery rate and the modulus are good, and the stretchability and flexibility are excellent. In addition, the film 21 for an adhesive substrate in each of the examples has a small weight increase rate after dipping in a Mittel solution or a liquid paraffin-based plasticizer, and has good chemical resistance. Also, bubble stability during inflation molding was excellent. Furthermore, the film for the adhesive substrate of each example
Since No. 21 is made of a non-halogen-based thermoplastic resin, there is no risk of generating harmful gas even if it is incinerated and discarded, and there is no problem of environmental pollution.

On the other hand, from Table 8, according to the two-layer laminated base material films according to Comparative Examples 7 and 9, the resin of the second layer was:
Although composed of an ethylene / α-olefin copolymer, the recovery ratio was low and the elasticity was poor because the thickness ratio of the second layer was smaller than the range of the present invention. According to the films for an adhesive substrate according to Comparative Examples 8 and 10, the resin of the second layer is composed of an ethylene / α-olefin copolymer, and the thickness ratio of the second layer is within the range of the present invention. Since the outer layer was much thinner, the outer layer was broken by elongation due to the tension at the time of drug application. Further, the rate of weight increase after immersion in the liquid paraffin plasticizer was high, and the chemical resistance was poor.

[0055]

According to the film for an adhesive substrate according to the present invention, since at least one of the three intermediate layers or one of the two layers is made of an ethylene / α-olefin copolymer having predetermined characteristics, it is flexible. Excellent in elasticity, stretchability and chemical resistance.
In addition, even if it is incinerated, no environmental problem occurs.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a film for an adhesive substrate according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a film for an adhesive substrate according to a second embodiment of the present invention.

[Explanation of symbols]

11,21 Film for base material to be adhered 12 First layer made of polyolefin polymer 13 Second layer made of ethylene / α-olefin copolymer according to first embodiment 14 Third layer made of polyolefin polymer 22 First layer made of ethylene / α-olefin copolymer according to second embodiment 23 Second layer made of polyolefin-based polymer

Claims (10)

[Claims] 1. A film for an adhesive substrate having an intermediate layer, wherein the intermediate layer is made of an ethylene / α-olefin copolymer, and the copolymer has the following characteristics (a to d). A film for an adhesive substrate, comprising: (A) Density 0.850 to 0.935 g / ml (b) MI 0.3 to 15.0 g / 10 min (c) Mw / Mn = 2.0 to 5.0 (d) Tm ≦ 125 ° C. 2. The film for an adhesive substrate according to claim 1, wherein the intermediate layer has the following property (e). (E) The molecular weight dependence width of the number of branches is 0 to 5/1000 carbon 3. The film for an adhesive substrate according to claim 1, wherein the intermediate layer has the following property (f). (F) I ₁₀ / I ₂ ≧ 5.63 and Mw / Mn ≦ (I ₁₀ /
I ₂₎ -4.63 4. The film for an adhesive substrate according to claim 1, wherein the film has an inner layer and an outer layer sandwiching the intermediate layer, and the inner and outer layers are made of a non-halogen thermoplastic resin. A film for an adhesive substrate, comprising: 5. The adhesive base film according to claim 1, wherein the thickness of the intermediate layer is 10 to 95% with respect to all layers. For film. 6. A film for an adhesive substrate having a two-layer structure, wherein one layer is made of an ethylene / α-olefin copolymer, and the copolymer has the following characteristics (a to d). A film for an adhesive substrate, comprising: (A) Density 0.850 to 0.935 g / ml (b) MI 0.3 to 15.0 g / 10 min (c) Mw / Mn = 2.0 to 5.0 (d) Tm ≦ 125 ° C. 7. The film for a pasting substrate according to claim 6, wherein the one layer has the following property (e). (E) The molecular weight dependence width of the number of branches is 0 to 5/1000 carbon 8. The film for an adhesive substrate according to claim 6, wherein the one layer has the following property (f). (F) I ₁₀ / I ₂ ≧ 5.63 and Mw / Mn ≦ (I ₁₀ /
I ₂₎ -4.63 9. The film for an adhesive substrate according to claim 6, wherein the other layer is made of a non-halogen thermoplastic resin. 10. The adhesive base film according to claim 6, wherein the thickness of the one layer is 10 to 90% with respect to all layers. Material film.