JP2018131524A - Film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film that has mechanical characteristics required for use as a film, and also has excellent adhesion to an adherend and re-peelability.SOLUTION: A film has at least one X face when the X face includes 200 or more projections per 1 cm, each projection of 110 μm or more and 1,000 μm or less high from a base line, and has a dynamic friction coefficient of 0.5 or more and 3.0 or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a film having excellent adhesion and releasability to a material such as cloth.

  In recent years, there has been a demand for a single film having a mechanical function necessary for use as a film and further having another function. For example, in the field of medical and hygiene materials, a material such as a cloth (hereinafter, referred to as an adherend) that has mechanical properties necessary for use as a film and has an uneven shape, stretchability, and flexibility. The film which has adhesiveness and peelability with respect to.

  So far, various developments have been made as films having adhesion to adherends. For example, Patent Document 1 discloses a hot-melt adhesive sheet having a concavo-convex shape in a specific arithmetic average roughness range. Patent Document 2 discloses a pressure-sensitive adhesive sheet having unevenness by embossing.

JP 2009-7532 A Japanese Patent Laid-Open No. 7-90231

  However, in the techniques of Patent Documents 1 and 2, it is difficult to achieve both adhesion and peelability to the adherend. Specifically, when the adhesion is strengthened, it becomes difficult to peel off, and the adhesive component remains on the adherend surface during peeling. On the other hand, if the adhesiveness is weakened, it becomes a problem that it peels off from the adherend during use.

  This invention makes it the subject to improve the fault of the prior art which concerns, and to provide the film which is provided with the mechanical characteristic required in order to use as a film, and is excellent in the adhesiveness and peelability with respect to a to-be-adhered body.

In order to solve the above problems, the present invention has the following configuration.
(1) When a surface having 200 or more convex portions with a height from the baseline of 110 μm or more and 1,000 μm or less per cm ² and having a dynamic friction coefficient of 1.0 or more and 5.0 or less is defined as the X plane And a film having at least one X-plane.
(2) The film according to (1), wherein the compression work measured according to the KES method is 0.02 gf · cm / cm ² or more and 0.5 gf · cm / cm ² or less.
(3) The shear strength of the film measured according to the KES method is 0.1 gf / (cm · deg) or more and 2.5 gf / (cm · deg) or less, (1) or (2) The film described.
(4) The film according to any one of (1) to (3), wherein an average major axis of the convex portion is 50 μm or more and 500 μm or less.
(5) When the layer having the X plane and containing 40% by mass or more and 100% by mass or less of the amorphous thermoplastic elastomer when the entire resin component in the layer is 100% by mass is defined as A layer, It has at least 1 A layer, The film in any one of (1)-(4) characterized by the above-mentioned.
(6) The amorphous thermoplastic elastomer is at least one selected from a styrene-ethylene-butadiene-styrene block copolymer, a styrene-butadiene-styrene block copolymer, and a styrene-isoprene-styrene block copolymer. The film according to (5), which is a resin.
(7) When a layer having a lower content of amorphous thermoplastic elastomer than the A layer is a B layer, the B layer is included, and the B layer is in contact with the A layer on the opposite side of the X plane. The film according to (5) or (6), wherein
(8) The film according to (7), wherein the B layer contains a crystalline thermoplastic elastomer in an amount of 80% by mass to 100% by mass when the entire resin component in the layer is 100% by mass. .

  According to the present invention, it is possible to provide a film having mechanical properties necessary for use as a film and excellent in adhesion and peelability to an adherend.

It is an enlarged top view (A) which shows the film which concerns on one embodiment of this invention, and the I-I 'cross section arrow directional view (B) in A. It is a schematic diagram which shows the cutting method of the film in the measurement of the height and number of convex parts. It is a schematic diagram showing the unevenness | corrugation difference of the embossing roll surface, and the pitch of the uneven | corrugated | grooved part of the embossing roll surface. It is a schematic diagram which shows the crimping | compression-bonding area in an embossing roll.

The film of the present invention has a surface having 200 or more protrusions per cm ² having a height from the baseline of 110 μm or more and 1,000 μm or less, and having a dynamic friction coefficient of 1.0 or more and 5.0 or less. In this case, it has at least one X plane. By setting it as such an aspect, a film is provided with a required mechanical characteristic, and becomes excellent in the adhesiveness and peelability with respect to a to-be-adhered body. Although the desirable form for implementing this invention is demonstrated below, this invention is not limited to this. Hereinafter, the height from the baseline may be referred to as the height of the convex portion.

(X side)
The film of the present invention has 200 protrusions per 1 cm ² having a height from the baseline of 110 μm or more and 1,000 μm or less from the viewpoint of improving the adhesion and peelability to the adherend while maintaining the mechanical properties. It is important to have at least one X plane when the plane having the above and having a dynamic friction coefficient of 1.0 to 5.0 is the X plane.

When the film of the present invention has 200 or more convex portions with a height from the baseline of 110 μm or more and 1,000 μm or less per 1 cm ^{2, the} surface having such convex portions is attached to the film of the present invention. When it adheres to a to-be-adhered body so that it may contact | connect a body, a convex part will fill the unevenness | corrugation of a to-be-adhered body. Therefore, the adhesion to the adherend is higher than that of a flat film.

  Hereinafter, the height of the base line and the convex portion will be described with reference to the drawings. FIG. 1: shows the enlarged top view (A) which shows the film which concerns on one embodiment of this invention, and the I-I 'cross section arrow directional view (B) in A. FIG. The baseline is vertical when the film 1 is placed on a horizontal table and the position data in the direction perpendicular to the horizontal plane is obtained for the entire film surface (the surface opposite to the table). The position of the direction. For example, in FIG. 1B, the line indicated by reference numeral 2 is the baseline. When there are multiple positions corresponding to the baseline including the film surface, the film surface is the baseline, and when there are multiple positions corresponding to the baseline without including the film surface, The near line is the baseline.

  The height of the convex portion refers to a difference in position between the baseline and the top of the convex portion in a direction perpendicular to the film surface (hereinafter sometimes referred to as a thickness direction) (corresponding to reference numeral 3 in FIG. 1B). . The height of the convex part is obtained by taking a cross section obtained by cutting the film parallel to the thickness direction using an ultramicrotome etc. with a microscope, etc., and using the obtained image, a length measuring function such as a microscope, etc. Can be measured.

  The height of the convex portion in the film of the present invention is preferably 200 μm or more and 800 μm or less, and more preferably 300 μm or more and 600 μm or less from the viewpoint of adhesion to the adherend.

From the viewpoint of adhesion to the adherend, the number of convex portions in the film of the present invention is preferably 500 or more per cm ² , more preferably 2,000 or more per cm ² . The upper limit of the number of convex portions is not particularly limited as long as the effect of the present invention is not impaired, but 10,000 per 1 cm ² is sufficient from the viewpoint of adhesion to an adherend. The number of protrusions can be measured by enlarging a sample piece of 1 cm (longitudinal direction) × 1 cm (width direction) with a magnifying glass or the like and counting the number of protrusions.

The method of forming 200 or more convex portions having a height from the base line of 110 μm or more and 1,000 μm or less per cm ^{2 on the} film surface is not particularly limited as long as the effects of the present invention are not impaired. From the viewpoint, embossing is preferably used. Below, embossing is demonstrated as an example.

  The embossing used in producing the film of the present invention is not particularly limited as long as the effects of the present invention are not impaired. For example, a method of combining a male embossing roll and an elastic roll such as a rubber roll, or a pair of There is a method of combining a male embossing roll and a female embossing roll. Further, the pattern (pattern) of the embossing roll is not particularly limited as long as the effect of the present invention is not impaired. Circular, square, parallelogram, heart pattern, star pattern, quadrangular pyramid pattern, truncated cone pattern, vertical line pattern , And horizontal line patterns can be used.

  In the film of the present invention, the average major axis of the protrusions is preferably 50 μm or more and 500 μm or less, more preferably 100 μm or more and 300 μm or less, and further preferably 100 μm or more and 200 μm or less. When the average major axis of the convex portion is less than 50 μm or exceeds 500 μm, the adhesion with the adherend may be lowered. In addition, the average major axis of a convex part can be measured with the following method.

  First, the surface having the convex portions of the film is observed with a scanning electron microscope, and a square or a rectangle is drawn so as to completely surround one convex portion and have the smallest area. In the case of a rectangle, the length of the long side is the major axis of the convex portion. Measurement is performed on any ten convex portions in one observation image, and the average value of the major axis of the convex portions obtained by performing the same measurement on ten observation images with different observation positions is obtained, and this is obtained as a film. The average major axis of the convex part of

  The film of the present invention has a dynamic friction coefficient of a surface having a convex portion of 1.0 or more and 5.0 or less, so that the adhesion with the adherend when the surface is attached so as to contact the adherend and The peelability to the adherend is improved. Here, the dynamic friction coefficient means a dynamic friction coefficient measured according to JIS K 7125: 1999. In addition, “Hize” (registered trademark) gauze NT-4 (manufactured by Asahi Kasei Corporation) is used as the counterpart material.

  When the dynamic friction coefficient of the surface having the convex portion is less than 1.0, the adhesion to the adherend may be lowered. Moreover, if the dynamic friction coefficient of the surface having the convex portion exceeds 5.0, the peelability to the adherend may be lowered. The dynamic friction coefficient of the surface having the convex portion is preferably 1.5 or more and 4.5 or less, more preferably 2.0 or more and 4 from the viewpoint of achieving both adhesion to the adherend and peelability to the adherend. 0.0 or less.

  The method of setting the dynamic friction coefficient of the surface having the convex portion to 1.0 or more and 5.0 or less or the above preferable range is not particularly limited as long as the effect of the present invention is not impaired, but for example, an amorphous thermoplastic elastomer described later A method for adjusting the content of the slag, a method for adjusting the height of the convex portion, and the like.

  More specifically, by increasing the content of the amorphous thermoplastic elastomer itself in the film, the Young's modulus of the film decreases and the film and its convex shape are easily deformed. The dynamic friction coefficient can be increased. In the case where the film has a laminated structure having an A layer and a B layer, which will be described later, the above-mentioned “content of the amorphous thermoplastic elastomer in the film” is “the amorphous thermoplastic elastomer in the A layer”. It should be interpreted as “content”. Furthermore, by increasing the height of the convex portion, the contact area with the concave and convex portions of the adherend increases, so that the dynamic friction coefficient can be increased.

In the film of the present invention, the surface having 200 or more protrusions per cm ² having a height from the baseline of 110 μm or more and 1,000 μm or less and a coefficient of dynamic friction of 1.0 or more and 5.0 or less is X A surface. As long as the X surface in the film of the present invention satisfies the above requirements, the height of the convex portions may be uniform or non-uniform. Moreover, unless the effect of this invention is impaired, you may have a convex part from which the height from a recessed part or a base line remove | deviates from the said range. Furthermore, as long as the film of the present invention has at least one X surface, the other surface is not particularly limited as long as the effects of the present invention are not impaired.

(Compression work)
In the film of the present invention, when the X surface is brought into contact with the adherend, the unevenness of the adherend is filled with the convex portions of the X surface so that the adhesion with the adherend is expressed. Therefore, it is preferable to maintain the shape of the convex portion when it is brought into contact with the adherend. The shape retention of the convex portion on the X surface can be expressed by using the work amount (compression work amount) when the film is compressed as a scale.

The compression work can be measured according to the KES method. The KES method is the Kawabata Evaluation System method. Hereinafter, the notation of the method is referred to as the KES method. Specifically, the film was compressed between a steel plate having a circular plane with an area of 2 cm ² under an atmosphere of a room temperature of 23 ° C. and a relative humidity of 65% under the conditions of a compression speed of 20 μm / sec and a maximum compression load of 10 gf / cm ² . It can be measured by the KES method. Hereinafter, the compression work measured according to the KES method is simply referred to as compression work.

The film of the present invention preferably has a compression work of 0.02 gf · cm / cm ² or more and 0.5 gf · cm / cm ² or less from the viewpoint of adhesion to an adherend. If the compression work is less than 0.02 gf · cm / cm ² , the shape retention of the convex portion on the X surface may be insufficient, and the adhesion to the adherend may be lowered. On the other hand, when the compression work exceeds 0.5 gf · cm / cm ² , the adherend and the convex portion of the X surface are not sufficiently adhered, and the adhesion to the adherend may be lowered. The amount of compression work from the point of view, more preferably 0.02gf · cm / cm ² or more 0.4gf · cm / cm ² or less, 0.02gf · cm / cm ² or more 0.3gf · cm / cm More preferably, it is ² or less.

The method for setting the compression work of the film of the present invention to 0.02 gf · cm / cm ² or more and 0.5 gf · cm / cm ² or less or the above preferable range is not particularly limited as long as the effect of the present invention is not impaired. However, for example, a method of adjusting the content of the crystalline thermoplastic elastomer described later, a method of adjusting the height of the convex portion, and the like can be mentioned.

  More specifically, by reducing the content of the crystalline thermoplastic elastomer in the film itself, when embossing is performed, the shape after deformation is more fixed and the shape retainability of the convex portion is improved. Therefore, the compression work can be increased. In the case where the film has a laminated structure having an A layer and a B layer, which will be described later, the “content of the crystalline thermoplastic elastomer in the film” is “the content of the crystalline thermoplastic elastomer in the B layer”. ". Further, by increasing the height of the convex portion, the degree of deformation when pressure is applied is increased, so that the compression work can be increased.

(Shear hardness (G))
The film of the present invention has a shear hardness (G) measured according to the KES method of 0.1 gf / (cm · deg) or more from the viewpoint of adhesion to a material having flexibility and stretchability such as an adherend. 0.5 gf / (cm · deg) or less is preferable.

The shear hardness (G) measured according to the KES method means the shear hardness (G) calculated from the shear stress in the longitudinal direction and the width direction measured according to the KES method. More specifically, the shear stress in the longitudinal direction and the width direction at points where the shear deformation is −2.5 °, −0.5 °, 0.5 °, and 2.5 ° is measured by the KES method. (hereinafter, respectively _HG -2.5 shear stress at each _point, HG _-0.5, HG _0.5, sometimes referred _{HG 2.5),} the longitudinal direction and the width direction, positive using the formula G1 Calculate the shear strength in the direction (G (+)) and the shear strength in the negative direction (G (-)) using the equation G2, and average G (+) and G (-) in the longitudinal and width directions. The shear hardness (G) obtained in this way. The conditions at the time of measuring the shear stress are 23 ° C., 65% relative humidity atmosphere, forced load 10 gf, shear shear rate 0.417 mm / sec, and sample shear deformation range −8 ° to 8 °. Hereinafter, the shear hardness (G) measured according to the KES method may be simply referred to as shear hardness (G).
Formula G1: G (+) = (HG _2.5 −HG _0.5 ) / (2.5 ° −0.5 °)
Formula G2: G (−) = (HG _−2.5 −HG _−0.5 ) / (− 2.5 ° − (− 0.5 °))
Here, the longitudinal direction refers to the direction in which the film proceeds when the film is produced, and the width direction refers to the direction orthogonal to the longitudinal direction. When the film is wound on a roll, the longitudinal direction and the width direction can be easily specified. However, in the case of a sheet-like film that is not wound on a roll, the longitudinal direction and the width direction Cannot be easily identified. In such a case, after measuring the Young's modulus of the film in one direction arbitrarily selected by the method described later, the film is rotated 5 ° to the right, the same measurement is performed, and this is repeated until 180 ° is reached. The direction with the largest Young's modulus is treated as the longitudinal direction. Hereinafter, the same applies to the present invention.

  From the viewpoint of adhesion to the adherend, the shear hardness (G) is more preferably 0.5 gf / (cm · deg) to 2.5 gf / (cm · deg), and more preferably 1.0 gf / More preferably, it is not less than (cm · deg) and not more than 2.5 gf / (cm · deg).

  In the film of the present invention, the method for adjusting the shear hardness (G) to 0.1 gf / (cm · deg) or more and 2.5 gf / (cm · deg) or less, or the preferable range described above, is effective for the present invention. Although it does not specifically limit unless it impairs, For example, the method of adjusting the content of the thermoplastic elastomer mentioned later, the method of adjusting the height of a convex part, etc. are mentioned.

  More specifically, by raising the content of the thermoplastic elastomer in the film itself, the Young's modulus of the film is lowered and the film and its convex shape are easily deformed, so that the shear strength of the film can be lowered. it can. Further, by increasing the height of the convex portion, the degree of spatial freedom is increased and the film and its convex shape are easily deformed, so that the shear strength of the film can be reduced.

(Layer structure)
The layer structure of the film of the present invention is not particularly limited as long as it has at least one X plane. However, from the viewpoint of easily setting the dynamic friction coefficient, the compression work amount, and the shearing hardness to a preferable range, the amorphous thermoplastic elastomer has an X plane and the resin component in the layer is 100% by mass. When a layer containing 40% by mass or more and 100% by mass or less is an A layer, it is preferable to have at least one A layer. Here, the amorphous thermoplastic elastomer has a crystal melting peak when heated from 25 ° C. to 250 ° C. at a heating rate of 20 ° C./min after being heated in a hot air oven at 100 ° C. for 24 hours. It refers to a thermoplastic elastomer that is not observed.

  As a specific example of such an embodiment, a single-layer film consisting of only the A layer, both surfaces or one side being the X plane, or the outermost layer on both sides or one side is the A layer, and at least one outermost surface is the X plane A certain laminated film is mentioned. In addition, the composition of A layer in the case of having a plurality of A layers may be the same or different unless the effects of the present invention are impaired.

  The content of the amorphous thermoplastic elastomer in the A layer exceeds 50% by mass when the total resin in the layer is 100% by mass from the viewpoint of easily making the dynamic friction coefficient and shear deformability within a desired range. It is preferably no greater than 50% by mass, more preferably greater than 50% by mass and no greater than 80% by mass, and even more preferably greater than 50% by mass and no greater than 75% by mass. At this time, when there are a plurality of amorphous thermoplastic elastomers in the layer, the content is calculated by adding up all the thermoplastic elastomers.

  As the amorphous thermoplastic elastomer in the A layer, from the above viewpoint, for example, polyester elastomer, polyolefin elastomer, polyamide elastomer, polyurethane elastomer, polystyrene elastomer, and polyacryl elastomer are used alone or in combination. A combination of the above can be used. Among these, from the above viewpoint, the amorphous thermoplastic elastomer is more preferably a polystyrene elastomer, and a styrene-ethylene-butadiene-styrene block copolymer, a styrene-butadiene-styrene block copolymer, and a styrene- It is more preferable that it is at least one resin selected from isoprene-styrene block copolymers, and particularly preferable is a styrene-ethylene-butadiene-styrene block copolymer.

  The layer A in the film of the present invention may contain a filler as long as the effect is not impaired. The filler is a substance added to improve various properties, or an inert substance added for the purpose of increasing the volume, increasing the volume, or reducing the cost of the product.

  The type of the filler is not particularly limited as long as the effects of the present invention are not impaired, and an inorganic filler and / or an organic filler can be used. Further, the filler may be one kind or a mixture of plural kinds. However, from the viewpoint of the coefficient of dynamic friction, the filler is preferably an inorganic filler. Metal carbonates such as calcium carbonate, barium carbonate and magnesium carbonate, metal sulfates such as barium sulfate and calcium sulfate, titanium oxide and zinc oxide It is preferable to use at least one of complex oxides such as metal oxides such as silicon oxide (silica), aluminosilicate, mica, talc, kaolin, clay, and montmorillonite. From the viewpoint of versatility and cost, calcium carbonate Is more preferably used alone or in combination with other fillers.

  The content of the filler in the A layer is not particularly limited as long as the effects of the present invention are not impaired. From the viewpoint of easily setting the dynamic friction coefficient to a desired range, when the total resin in the A layer is 100 parts by mass. It is preferably 5 parts by mass or more and 200 parts by mass or less, more preferably 15 parts by mass or more and 70 parts by mass or less, and further preferably 20 parts by mass or more and 50 parts by mass or less. In addition, when there are a plurality of fillers in the layer having the X plane, the filler content is calculated by adding all the fillers.

  From the viewpoint of improving embossability, the film of the present invention has a B layer when the layer having a lower amorphous thermoplastic elastomer content than the A layer is a B layer, and the B layer is an X plane. It is preferable to contact the A layer on the opposite side. Here, the “layer having a lower content of amorphous thermoplastic elastomer than layer A” means the content (% by mass) of the amorphous thermoplastic elastomer in the layer with respect to 100% by mass of the entire resin component in the layer. Is a layer lower than the amorphous thermoplastic elastomer content (% by mass) in the A layer with respect to 100% by mass of the entire resin components in the A layer. In addition, “the B layer is in contact with the A layer on the opposite side of the X surface” means that one surface of the A layer is the X surface, and the surface of the A layer opposite to the X surface is in direct contact with the B layer. Say.

  Embossing is a process in which a film is thermally deformed by a heated embossing roll. And since the content of an amorphous thermoplastic elastomer is lower than the A layer, the B layer has a more stable shape when heated than the A layer. Therefore, by setting it as such an aspect, it can suppress that a film deform | transforms excessively at the time of embossing.

  The composition of the B layer in the film of the present invention is not particularly limited as long as the effects of the present invention are not impaired, but the B layer has a crystalline thermoplastic elastomer of 50 mass when the total resin component in the layer is 100 mass%. % To 100% by mass, more preferably 75% to 100% by mass. Here, the crystalline thermoplastic elastomer is a crystal melting peak observed when heated from 25 ° C. to 250 ° C. at a temperature rising rate of 20 ° C./min after being heated in a hot air oven at 100 ° C. for 24 hours. Refers to a thermoplastic elastomer. By setting it as such an aspect, since the deformation | transformation of B layer by a heat | fever is reduced, the shape of a film becomes more stable at the time of embossing.

  The crystalline thermoplastic elastomer in the B layer is not particularly limited as long as the effects of the present invention are not impaired. For example, a polyester elastomer, a polystyrene elastomer, a polyolefin elastomer, a polyurethane elastomer, and a polyamide elastomer are used alone or They can be used in combination. Especially, it is preferable to use a polyester-type elastomer and a polyamide-type elastomer individually or in combination from a viewpoint of embossing property.

  Examples of the polyester-based elastomer that can be used in the film of the present invention include a block copolymer of an aromatic polyester and an aliphatic polyester, and a block copolymer of an aromatic polyester and an aliphatic polyether. From the viewpoint of imparting moisture permeability, it is preferable to use a block copolymer of an aromatic polyester and an aliphatic polyether. Examples of the polyamide-based elastomer that can be used in the film of the present invention include a block copolymer of an aliphatic polyamide and an aliphatic polyester, and a block copolymer of an aliphatic polyamide and an aliphatic polyether. However, from the viewpoint of imparting moisture permeability, it is preferable to use a block copolymer of an aliphatic polyamide and an aliphatic polyether.

(Film production method)
Next, although the production method of the film of the present invention will be described more specifically by taking a single layer film as an example, the production method of the film of the present invention is not limited to this.

  In obtaining a composition used for obtaining the film of the present invention, that is, a composition containing a thermoplastic elastomer, a filler and the like, it is preferable to use a melt-kneading method in which each component is melt-kneaded. The mixer used in the melt-kneading method is not particularly limited, and a known mixer such as a kneader, a roll mill, a Banbury mixer, and a single-screw or twin-screw extruder can be used. Among these, from the viewpoint of productivity, it is preferable to use a single screw or twin screw extruder.

  Next, using the composition obtained by the above-described method, a non-oriented film is produced by a known film forming method such as an inflation method, a tubular method, and a T die casting method. The obtained non-oriented film may be subjected to uniaxial stretching or biaxial stretching of a roll type stretching machine. However, it is preferable not to perform stretching in order to set the shear hardness and compression work to the above-mentioned preferable ranges and to give embossability.

  After the film is formed, various surface treatments may be applied for the purpose of improving printability, laminate suitability, coating suitability, and the like. Examples of the surface treatment method include corona discharge treatment, plasma treatment, flame treatment, and acid treatment. Either method can be used, but a corona discharge treatment is preferable because continuous treatment is possible and the apparatus can be easily installed in an existing film-forming facility and the treatment is simple.

  The film thus obtained is embossed through two embossing rolls to obtain the film of the present invention. At this time, the roll temperature is preferably 20 to 150 ° C., the nip pressure (linear pressure) is preferably 20 to 100 kg / cm, and the roll rotation speed is preferably 0.5 to 30 m / min. In addition, the combination of an embossing roll can use the combination of elastic rolls, such as a male embossing roll and a rubber roll, and the combination of a pair of male embossing roll and a female embossing roll, for example.

(Other uses)
The film of the present invention is a film having excellent mechanical properties necessary for use as a film, and excellent adhesion, releasability, and followability to make an adherend having an uneven surface like a cloth. Can be suitably used. Furthermore, the film of this invention is good also as a laminated body with a nonwoven fabric.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited thereto.

[Measurement and evaluation method]
Measurements and evaluations shown in the examples were performed under the following conditions.

(1) Film thickness A sample piece is cut out from the center portion of the obtained film, and a cross section in the longitudinal direction-thickness direction of the sample piece (hereinafter sometimes referred to as a film cross section) is used as an observation surface using an ultramicrotome. Ultrathin sections were collected at -100 ° C. Using a scanning electron microscope (S-3400N, manufactured by Hitachi High-Technologies Corporation), a photograph of the film cross section was taken at a magnification of 1,000 times, and the thickness of the film was measured using the measuring function of the microscope. The measurement was performed 10 times while changing the observation location, and the average value of the obtained values was defined as the thickness (μm) of the film. The film thickness was a value obtained by rounding off the first decimal place. Here, the thickness direction means a direction perpendicular to the film surface.

(2) Using a dynamic friction coefficient testing apparatus for a surface having a convex portion (“HEIDON” manufactured by Shinto Chemical Co., Ltd.), the friction coefficient of the surface having a convex portion is measured according to JIS K 7125: 1999. It was. As the other material, “Hize” (registered trademark) Gauze NT-4 (manufactured by Asahi Kasei Corporation) was used. The measurement was performed three times in each of the longitudinal direction and the width direction (6 times in total), and the average value of all the data was defined as the dynamic friction coefficient of the surface having the convex portion.

(3) Cut the sample piece from the height of the film convex part and the center part of the number film, and cut it at -100 ° C. parallel to the longitudinal direction and perpendicular to the film surface with an ultramicrotome (4-4 ′ in FIG. 2). ), A cross-section was performed. Using a microscope, the image was observed from the horizontal direction at a magnification (for example, 5 times) at which the height of the convex portion can be confirmed. Subsequently, image capturing was repeated while shifting the observation position in the horizontal direction, and cross-sectional images for a continuous region over a length of 2 cm were collected. In the obtained cross-sectional image, the height of the convex portion was measured, and the convex portion having a depth from the baseline of 110 μm or more and 1,000 μm or less was extracted. Subsequently, the film was cut perpendicularly to the film surface along the direction (5-5 ′ in FIG. 2) rotated clockwise by 15 ° in the plane from the width direction of the film, and the cross section was similarly formed. Extraction was performed. Thereafter, as shown in FIG. 2, the cutting angle in the film plane is shifted by 15 ° (6-6 ′ → 10-10 ′ in FIG. 2) to obtain cross-sections having different in-plane cutting angles, and each time the convexity is raised. Parts were extracted. The cross-section was performed seven times in total. An average value was obtained for the height of the convex portion from each of the cross sections thus obtained, and was defined as the height of the convex portion. Subsequently, a sample piece of 1 cm (longitudinal direction) × 1 cm (width direction) was cut out from the center portion in the width direction of the film to obtain a sample having an area of 1 cm ² , and the number of convex portions was measured with a magnifying glass (magnification magnification: 10 times) It was measured.

(4) From the evaluation results of “(2) dynamic friction coefficient of surface having convex portions” and “(3) height and number of film convex portions”, the height from the baseline is 110 μm or more, The surface having 200 or more convex portions of 000 μm or less per cm ² and having a dynamic friction coefficient of 1.0 or more and 5.0 or less was defined as an X plane.

(5) Compression work of film A film was cut into a size of 12 cm (longitudinal direction) × 12 cm (width direction) and used as a sample and attached to a test stand. Next, using an automated compression test apparatus KES-FB3-A manufactured by Kato Tech, the attached sample was compressed between steel plates having a circular plane with an area of 2 cm ² , a compression speed of 20 μm / sec, a maximum compression load of 10 gf / cm ² , room temperature. The film was compressed under an atmosphere of 23 ° C. and a relative humidity of 65%, and the compression work (gf · cm / cm ² ) of the film was measured. The measurement was performed 3 times (6 times in total) on both the inner and outer surfaces of the film, and the value obtained by rounding off the third decimal place of the average value of all the data was taken as the compression work of the film.

(6) Shear hardness of film (G)
The film was cut into a size of 12 cm (longitudinal direction) × 12 cm (width direction) and used as a sample, which was attached to a test bench. Next, using a shear tester KES-FB1-A manufactured by Kato Tech Co., Ltd., a sample having a load of 10 gf and a shear shear rate of 0.417 mm / sec in an atmosphere of 23 ° C. and a relative humidity of 65% was −8. The shear stress was measured at points where the shear deformation was -2.5 °, -0.5 °, 0.5 °, and 2.5 ° (hereinafter referred to as each point). the shear stress respectively _{HG -2.5, HG -0.5, HG 0.5} , sometimes referred _{HG 2.5.).} From HG _0.5 and HG _2.5 , the following equation G1 is used to determine the shear strength (G (+)) in the positive direction, and from HG _-2.5 and HG _-0.5 , the following equation G2 is used to indicate the negative direction. Shear hardness (G (-)) was calculated. Measurement of shear stress and calculation of G (+) and G (-) are performed 3 times in both the longitudinal direction and the width direction (6 times in total), and the average value of all G (+) and G (-) values The value obtained by rounding off the third decimal place was defined as the shear hardness (G) (gf / (cm · deg)) of the film.
Formula G1: G (+) = (HG _2.5 −HG _0.5 ) / (2.5 ° −0.5 °)
Formula G2: G (−) = (HG _−2.5 −HG _−0.5 ) / (− 2.5 ° − (− 0.5 °))
When measuring the shear strength (G) in the longitudinal direction, the sample is attached so that the longitudinal direction of the film is orthogonal to the shear deformation direction, and when measuring the shear strength (G) in the width direction, the width of the film The sample was mounted so that the direction was perpendicular to the shear deformation direction.

(7) Embossing Embossing was carried out through a film between any of the following embossing rolls (I) to (VII) set in the electric heating type embossing machine HTEM-300 type manufactured by Yuri Roll Co., Ltd. and a rubber roll. The temperature of the embossing roll and rubber roll was 120 ° C., the nip pressure (linear pressure) was 50 kg / cm, and the rotation speed was 3.0 m / min.
<Emboss roll (I)>
Pattern: Concavity and convexity difference on the surface of a square convex emboss roll: 110 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (II)>
Pattern: unevenness on the surface of a square convex embossing roll: 200 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (III)>
Pattern: Convex difference on the surface of a square convex embossing roll: 300 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (IV)>
Pattern: unevenness on the surface of a square convex embossing roll: 600 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (V)>
Pattern: unevenness on the surface of a square convex embossing roll: 800 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (VI)>
Pattern: unevenness on the surface of a square convex embossing roll: 1,000 μm
Embossing roll surface unevenness pitch: 200 μm
Area of convex mold: 0.01 mm ²
<Emboss roll (VII)>
Pattern: unevenness on the surface of a square convex embossing roll: 600 μm
Embossing roll surface unevenness pitch: 100 μm
Area of convex mold: 0.0025 mm ²
<Emboss roll (VIII)>
Pattern: unevenness on the surface of a square convex embossing roll: 600 μm
Embossing roll surface irregularity pitch: 400 μm
Area of convex mold: 0.04 mm ²
<Emboss roll (IX)>
Pattern: unevenness on the surface of a square convex embossing roll: 600 μm
Embossing roll surface unevenness pitch: 600 μm
Area of convex mold: 0.09 mm ²
<Emboss roll (X)>
Pattern: unevenness on the surface of a square convex embossing roll: 600 μm
Embossing roll surface irregularity pitch: 800 μm
Area of convex mold: 0.16 mm ²
<Emboss roll (XI)>
Pattern: unevenness on the surface of a square convex embossing roll: 100 μm
Embossing roll surface irregularity pitch: 400 μm
Area of convex mold: 0.04 mm ²
<Emboss roll (XII)>
Pattern: unevenness on the surface of a square convex embossing roll: 1,100 μm
Embossing roll surface irregularity pitch: 400 μm
Area of convex mold: 0.04 mm ²
The unevenness on the surface of the embossing roll refers to the height of the convex portion on the surface of the embossing roll (corresponding to reference numeral 11 in FIG. 3), and the pitch of the unevenness on the surface of the embossing roll refers to the embossing roll provided periodically. It refers to the length of one period of the uneven portion on the surface. (Equivalent to reference numeral 12 in FIG. 3) The crimping area refers to the area of the embossing roll surface having the highest height per pattern of the embossing roll (corresponding to reference numeral 13 × reference numeral 14 in FIG. 4). .

(8) The adhesive film was cut into a strip shape having a length of 100 mm and a width of 10 mm to obtain a sample for adhesion evaluation. The sample for evaluation was affixed on the adherend (“Hize” (registered trademark) gauze NT-4 (manufactured by Asahi Kasei Corporation)) using a laminate roller. Next, the peel strength between the film and the adherend was measured using a tensile testing machine ("Tensilon" (registered trademark) UCT-100 manufactured by Orientec) at a tensile speed of 300 mm / min. The peel strength was measured according to JIS K 6854-1: 1999. The measurement was performed for each sample at five points, and evaluation was performed using an average value of the five points. The obtained peel strength was classified according to the following criteria, and C or higher was regarded as acceptable.
S: 400 mN / cm or more A: 300 mN / cm or more and less than 400 mN / cm B: 150 mN / cm or more and less than 300 mN / cm C: 50 mN / cm or more and less than 150 mN / cm D: Less than 50 mN / cm (9) Film and adherend The peel strength film was cut into a square having a length of 100 mm and a width of 100 mm to obtain a sample for evaluation of peelability. The sample for evaluation was affixed on the adherend (“Hize” (registered trademark) gauze NT-4 (manufactured by Asahi Kasei Corporation)). The film and adherend were sandwiched between 10 cm × 10 cm glass plates, and a load of 10 kgf was applied and left in an oven at 40 degrees for 3 hours. After taking out from the oven, the peel strength between the film and the adherend was measured according to JIS K 6854-1: 1999 using a tensile tester ("Tensilon" (registered trademark) UCT-100 manufactured by Orientec). . At this time, the tensile speed was 300 mm / min. The measurement was performed at 5 points per sample. The obtained peel strength was classified according to the following criteria, and C or higher was regarded as acceptable. The film of the present invention is excellent in peelability, that is, it is preferable that the peel strength is low. However, when the peel strength is less than 5 mN / cm, there is no adhesion to the adherend and the object of the present invention is achieved. It was rejected because it did not.
S: 5 mN / cm or more and less than 100 mN / cm A: 100 mN / cm or more and less than 300 mN / cm B: 300 mN / cm or more and less than 600 mN / cm C: 600 mN / cm or more and less than 1,500 mN / cm D: 1,500 mN / cm or more Or less than 5 mN / cm (10) The surface having the convex portion of the average long-diameter film of the convex portion is observed with a scanning electron microscope, and a square or a rectangle is formed so as to completely surround one convex portion and minimize the area. In the case of a square, the length of one side is taken as the long diameter, and in the case of a rectangle, the length of the long side is taken as the major diameter of the convex portion. Measurement is performed on any ten convex portions in one observation image, and the average value of the major axis of the convex portions obtained by performing the same measurement on ten observation images with different observation positions is obtained, and this is obtained as a film. It was set as the average major axis of the convex part.
[Thermoplastic elastomer]
(A1) Styrene-ethylene-butadiene-styrene block copolymer (trade name: “DYNARON” (registered trademark) 8903P, manufactured by JSR Corporation) An amorphous thermoplastic elastomer.
(B1) Polyester elastomer (trade name: “Hytrel” (registered trademark) G3548, manufactured by Toray DuPont Co., Ltd.) It is a crystalline thermoplastic elastomer.
[filler]
(C1) Calcium carbonate (trade name: SCP E # 810, aspect ratio 2, average particle size 3.0 μm, manufactured by Sankyo Seimitsu Co., Ltd.)
[Production of film]
Example 1
A1, B1, and C1 are supplied to a twin-screw extruder with a vacuum vent of 44 mm and a cylinder diameter of 175 ° C. with the contents shown in Table 1, melt-kneaded, homogenized, and pelletized to obtain the composition in each layer. Obtained. The pellets of this composition were pressed with a desktop hot press (small press G-12, manufactured by Techno Supply Co., Ltd.) at a press temperature of 220 ° C. and a pressure of 40 MPa for 1 minute, a sheet corresponding to the A layer, and the B layer A sheet corresponding to was obtained. Next, each obtained sheet was cut into a size of 20 cm × 20 cm, and heat-laminated using a thermal laminator (manufactured by MCK Corporation, MRK-600) under the following conditions to form layers A and B A laminated film consisting of layers was obtained. Next, the obtained laminated film was embossed under the conditions shown in Table 1 to obtain a film having convex portions. The properties and evaluation results of the obtained film are shown in Table 1.
<Thermal lamination conditions>
Roll temperature: 120 ° C
Roll speed: 1m / min
Roll wire pressure: 0.5 MPa
(Examples 2 to 13, Comparative Examples 1 to 4)
A film having a convex shape on the surface was obtained by the method described in Example 1 except that A1, B1, C1 and embossing were as described in Tables 1 and 2. The characteristics and evaluation results of the obtained film are shown in Tables 1 and 2.

(Comparative Example 5)
A film having no projections was obtained in the same manner as in Example 1 except that the embossing was not performed. The properties and evaluation results of the obtained film are shown in Table 2.

The content (mass%) of A1 and B1 in each layer was calculated with 100 mass% of the entire resin in the layer, and the content (mass part) of C1 was calculated with 100 mass parts of the entire resin in the layer. The same applies to Table 2.

Since the film of Comparative Example 5 does not have a convex portion, the dynamic friction coefficient in the layer whose composition satisfies the requirements of the A layer is shown as “the dynamic friction coefficient of the surface having the convex portion”.

  According to the present invention, it is possible to provide a film having mechanical properties necessary for use as a film and excellent in adhesion and peelability to an adherend. The film of the present invention is used in applications requiring adhesion and removability to an adherend, specifically medical / hygiene such as bed sheets, pillow covers, back sheets of absorbent articles such as sanitary napkins and paper diapers. Materials, clothing for rain, clothing materials such as gloves, garbage bags and compost bags, food bags such as vegetables and fruits, packaging materials such as bags for various industrial products, building materials such as buildings, houses, decorative boards, railway vehicles, It can be preferably used for interior materials, building materials, and the like in transport aircraft such as ships and aircraft.

DESCRIPTION OF SYMBOLS 1 Film 2 Baseline 3 Height of convex part 4-4 'Cutting surface 5-5' parallel to a longitudinal direction 5-5 'Cutting surface 6-6' 5-5 'shifted | deviated 15 degrees clockwise with respect to 4-4' With respect to the cutting surface 7-7 ′ 6-6 ′ which is shifted 15 ° clockwise relative to the cutting surface 8-8 ′ 7-7 ′ which is shifted 15 ° clockwise with respect to the cutting surface 7-7 ′ 6-6 ′. Cutting surface 9-9 '8-8' Cutting surface 10-15 'shifted 15 ° clockwise 15 ° Cutting surface 15 ° clockwise offset 11 Embossing roll surface unevenness difference 12 Embossing roll surface irregularity pitch 13 × 14 crimping area

Claims (8)

When a surface having a height from the baseline of 110 μm or more and 1,000 μm or less is 200 or more per cm ² and the dynamic friction coefficient is 1.0 or more and 5.0 or less is defined as X surface, A film having at least one surface. The film according to claim 1, wherein the compression work measured according to the KES method is 0.02 gf · cm / cm ² or more and 0.5 gf · cm / cm ² or less.   The film according to claim 1 or 2, wherein the film has a shear strength of 0.1 gf / (cm · deg) or more and 2.5 gf / (cm · deg) or less measured according to the KES method.   The film according to any one of claims 1 to 3, wherein an average major axis of the convex portion is 50 µm or more and 500 µm or less.   When the layer having the X plane and containing 40% by mass or more and 100% by mass or less of the amorphous thermoplastic elastomer when the total resin component in the layer is 100% by mass is at least one It has A layer, The film in any one of Claims 1-4 characterized by the above-mentioned.   The amorphous thermoplastic elastomer is at least one resin selected from a styrene-ethylene-butadiene-styrene block copolymer, a styrene-butadiene-styrene block copolymer, and a styrene-isoprene-styrene block copolymer. The film according to claim 5, wherein   When a layer having a lower content of amorphous thermoplastic elastomer than the A layer is a B layer, the B layer is provided, and the B layer is in contact with the A layer on the opposite side of the X plane. The film according to claim 5 or 6. The film according to claim 7, wherein the layer B contains 80% by mass or more and 100% by mass or less of a crystalline thermoplastic elastomer when the total resin component in the layer is 100% by mass.

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