JP4888098B2 - wallpaper - Google Patents

Description

  The present invention relates to wallpaper obtained by laminating a polypropylene film on a base material. More specifically, the present invention relates to a wallpaper having moisture permeability and waterproofness, high whiteness, cushioning rate, and embossing rate and excellent light discoloration resistance.

Conventionally, wallpaper that has been embossed by applying vinyl chloride to backing paper has been widely used. However, it has been pointed out that vinyl chloride may generate dioxins during incineration. In recent years, despite the fact that houses have a high airtight structure, conventional interior materials such as wallpaper do not have any special anti-condensation measures, so surface condensation cannot be avoided, and wallpaper due to water absorption cannot be avoided. Deterioration, generation of mold, and accompanying problems such as contamination of the surface of wallpaper. In addition, when the conventional wallpaper is wiped with a wet cloth when it is contaminated, there is a problem that it is difficult to wipe off because the water soaks into the wallpaper, or discoloration (yellowing) due to fluorescent light or ultraviolet rays from the outdoors. . As a solution to these problems, there is a wallpaper in which a polymer coating layer of a moisture absorbing and releasing polyethylene resin containing diatomaceous earth or the like is provided on the surface side of a backing paper (Patent Document 1). However, since Patent Document 1 contains diatomaceous earth or the like in a polyethylene resin, there are problems of stickiness when moisture is absorbed and poor printability and weather discoloration. Furthermore, there is a concern that particles such as diatomaceous earth contained in the resin float in the air with the passage of time, and the particles are sucked to affect the human body.
In addition, there is an interior paper in which a water-permeable resin layer of a porous polyolefin film is laminated on a water-absorbing base paper (Patent Document 2). However, in Patent Document 2, a hole is formed in a polyolefin film for the purpose of allowing water adhering to the interior paper to quickly pass through the water-absorbent base paper, and the preferable hole diameter is as large as 20 μm or more. In order to use a laser beam etc., it is expensive. The wallpaper is obtained by sequentially laminating a decorative resin layer and a surface resin coating layer on a backing material, and a polyolefin resin is used for the surface resin coating layer, and the surface tension is 40 mN / m or less. There is a dirt prevention wallpaper (Patent Document 3). However, Patent Document 3 is to prevent soiling due to the starch-based adhesive used when pasting the wallpaper, and is inferior in air permeability and dew condensation prevention in the performance of the wallpaper itself, and the conventional polyolefin film is embossed. It was inferior in processability, inferior in transferability from a wallpaper pattern, and inferior in productivity and appearance.

Moreover, there is a wallpaper obtained by laminating a polybutylene terephthalate film having through holes on a base material (Patent Document 4). In Patent Document 4, a polybutylene terephthalate film having good moldability is laminated on a substrate such as paper. However, in order to make a hole in the polybutylene terephthalate film, a hole is physically made, and the opening system is Since it was as large as 0.5 to 3 μm, it was difficult to control air permeability and moisture permeability, and there were problems such as penetration of an aqueous material adhering to the surface.
JP 2003-3382 A (Claim 1) JP-A-2004-360128 (Claims 1 and 2) JP-A-2005-171457 (Claims 1, 3, and 4) JP-A-2005-163242 (Claims 1, 3, and 4)

  An object of the present invention is to provide a wallpaper having a high cushion rate as a wallpaper, excellent embossability, high moisture permeability and air permeability, excellent anti-condensation properties, and excellent color change resistance.

In order to solve the above-described problems, the present invention mainly has the following configuration. That is, the present invention is a wallpaper obtained by laminating a polypropylene film on a base material, and the polypropylene film has at least two layers of a core layer and a skin layer, and the porosity of the skin layer is a core layer. lower than the porosity, the whiteness of the polypropylene fill beam is 60% or more, cushion factor is 15% or more, embossing rate is equal to or less than 10%.

In a more preferred embodiment, the Gurley permeability of the wallpaper is in the range of 100 to 100,000 g / (m ² · d), the polypropylene film has a porosity of 20% or more, has substantially no void core, and is totally transmissive. When the rate is 10 to 40%, the Gurley permeability is 10 to 5000 sec / 100 ml, the color change rate after exposure to ultraviolet rays is 5% or less, and the porosity of the polypropylene film is 40% or more. And having a β crystal activity and having a β crystal ratio of 25% or more and fine particles having an average particle size in the range of 0.06 to 0.4 μm, and the content of the fine particles is 3 to 20 it is an picture characterized by the weight percent der Turkey.

  ADVANTAGE OF THE INVENTION According to this invention, the wallpaper which has the characteristic outstanding as a dew condensation prevention of a building interior material can be provided as demonstrated below.

  (1) High whiteness, high cushioning, excellent embossability, excellent transferability and printability from the pattern for wallpaper, and a highly designable wallpaper with a good feel as an interior material. Obtainable.

  (2) Since it is excellent in air permeability and moisture permeability and waterproofness, it is excellent in anti-condensation property of the interior material, and it is possible to suppress deterioration of wallpaper due to water absorption and generation of mold.

  (3) The polypropylene film does not substantially have void nuclei, and there is no fear that particles that become fillers and void nuclei as in the past peel off from the film, float in the air, and be sucked into the human body.

  (4) By making the total light transmittance of a polypropylene film into a specific range, when a polypropylene film is laminated | stacked on the base material with which the character and the design were printed, it looks like a frosted form and design property can be improved.

  (5) The color change rate after exposure to ultraviolet rays is low, and the color of the wallpaper can be maintained for a long time.

  (6) Since the polypropylene film has two or more layers provided with a skin layer having a low porosity, it is difficult to cleave and torn.

  Hereinafter, the best mode for obtaining the wallpaper of the present invention and the case where the wallpaper is applied to an interior material will be described as an example.

  In the wallpaper of the present invention, the whiteness of the polypropylene film laminated on the base material is preferably 60% or more, more preferably 70% or more, and preferably close to 100%. When the whiteness of the polypropylene film is 60% or more, the transferred wallpaper pattern and the printed pattern become clear and the design is enhanced, which is preferable. If the degree of whiteness is less than 60%, the transferred wallpaper pattern or the printed pattern becomes unclear, and the design is lowered. Therefore, it is not preferable because it is necessary to perform white background printing or the like on the film surface.

  In the wallpaper of the present invention, the cushion rate of the polypropylene film laminated on the substrate is preferably 15% or more, and the cushion rate is in the range of 18 to 25%. It is more preferable because it has good properties and is excellent in feel of the obtained wallpaper. When the cushion rate is less than 15%, the embossability is poor and the feel of the obtained wallpaper is also unfavorable.

  In addition, the embossing rate of the polypropylene film is preferably 10% or more, and the range of 12 to 30% improves the transferability of the unevenness depth of the wallpaper pattern and improves the workability. More preferred. The embossing rate indicates the transferability of the unevenness of the plate of the wallpaper design, and is determined by the ratio between the unevenness of the plate and the unevenness of the film. If the embossing rate is less than 10%, the productivity of the wallpaper is inferior, and the appearance of the obtained wallpaper is also inferior.

  As a polypropylene film laminated | stacked on the base material of the wallpaper of this invention, the microporous polypropylene film manufactured by a well-known method can be used. Examples of the manufacturing technique include an extraction method, a lamellar stretching method and an inorganic particle method, and a β crystal method.

    The extraction method is a method in which an extract is added to a polyolefin, finely dispersed, formed into a film, and then the extract is extracted with a solvent or the like to form pores (stretching is performed before and after extraction as necessary) ( For example, Japanese Patent No. 1299979). In addition, the lamellar stretching method uses a low-temperature extrusion at the time of film by melt extrusion to produce an unstretched film in which a special crystalline lamellar structure is formed by taking special melt crystallization conditions of a high draft, which is mainly uniaxially stretched. This is a method of cleaving the lamella interface to form a hole (for example, Japanese Patent No. 1046436). The inorganic particle method is a method of forming pores by peeling an interface between different materials by stretching an unstretched film in which a large amount of incompatible particles such as inorganic particles are added to polyolefin (see, for example, JP-A-2001-294695). No., JP 2004-307730 A). Further, the β crystal method is a production method using a special crystal form of polypropylene. In this method, a β crystal nucleating agent is contained in a polypropylene resin to produce a β crystal having a low density at the time of casting (crystal density: 0.922 g / cm 3), and an α crystal having a high density at the time of stretching (crystal density: 0.936 g / cm3), and a method of generating pores using the density difference (for example, Japanese Patent No. 3291307, Japanese Patent Application Laid-Open No. 2005-171230, International Publication No. 05/103127 pamphlet) International Publication No. 03/093004 pamphlet). The extraction method is expensive because it uses a solvent, and has manufacturing defects such as contaminating the environment due to the treatment of the emitted solvent. Also, the lamella stretching method is similar to the extraction method because the process is special. However, while the inorganic particle method uses a large amount of inorganic particles, the inorganic particles fall off, contaminating the process, and tearing the film during film formation. Paper dust trouble is likely to occur, and since inorganic particles etc. are dispersed non-uniformly, non-uniform micropores are generated and it is very difficult to control the pore diameter. The polypropylene film used for the wallpaper of the invention is preferably a microporous polypropylene film produced by a β crystal method.

  It is preferable that the polypropylene film used for the wallpaper of the present invention has a porosity of 20% or more and substantially has no void nucleus. When the porosity is less than 20%, the cushion rate and the embossing rate are lowered, the Gurley air permeability is also increased, and the air permeability is lowered. More preferably, it is 20 to 90% of range. If the porosity exceeds 90%, the film tends to be cleaved and easily broken, which may cause a problem in embossability, and when used as wallpaper, it tends to be broken by rubbing, which is not preferable.

In order to obtain a high cushioning rate, embossing rate and porosity of the polypropylene film, it is preferable that the polypropylene film contains fine and numerous voids, and the number of voids per 100 μm ² of the cross-sectional area of the film is 20, preferably 50. The number is more preferably 100 or more.

  Further, the polypropylene film is preferable because it has substantially no void nuclei, thereby increasing the cushion rate and the embossing rate. General-purpose transparent polypropylene film has a low cushioning rate of 5% or less because there are few internal voids, and conventionally, inorganic or organic particles have been added as void-forming materials to form voids and increase porosity In addition, an incompatible resin property is added to polypropylene and biaxially stretched to form a void having a void forming material as a core. However, a film in which a large amount of void forming material is added to a conventional polypropylene resin, when stretched, huge pores are formed due to poor dispersibility or agglomeration of the void forming material, and the film strength is low and easily broken, There is a possibility that void nuclei fall off in the film forming process and embossing process, and film tears and processes become dirty, and when used as wallpaper, the void nuclei are sucked to affect the human body.

Here, “substantially having no void nucleus” means a cross-sectional photograph taken by magnifying the cross section of the film at 8000 times using a scanning electron microscope S-2100A type (manufactured by Hitachi, Ltd.). , The total number of voids per 100 μm ² (single bubbles having a boundary line), the number of voids having nuclei, and the value obtained by dividing the number of voids having nuclei by the total number of voids is substantially less than 5%. It has no void nuclei. In addition, for the observation of voids in the film cross section, a total of 10 cross-sectional photometers arbitrarily selected from different measurement fields were used.

Further, the number of void-free voids of the polypropylene film is preferably 20/100 μm ² or more, and preferably 50 or more, since the whiteness, cushion ratio, and embossing ratio are increased.

  Next, the Gurley air permeability of the polypropylene film is preferably in the range of 10 to 5000 sec / 100 ml. The Gurley air permeability indicates the time required for 100 cc of air to permeate per specified area. The shorter the time, the better the air permeability. However, if the Gurley air permeability is less than 10 sec / 100 ml, the air permeability is too high. In some cases, the temperature control property of the liquid is lowered, and if it exceeds 5000 sec / 100 ml, the air permeability is poor and condensation tends to occur, which is not preferable.

  In order to obtain the Gurley permeability of the polypropylene film, it is obtained by increasing the non-nuclear void ratio in the film, and when a void forming material having an average particle size of 1 μm or more is contained, an excessive void is formed, This is not preferable because the number of voids decreases and the air permeability decreases.

  Further, the polypropylene film preferably has a color tone change of 5% or less after being exposed to ultraviolet rays. The change in color tone after exposure to ultraviolet rays is a measure of the color change rate before and after the film was forced to irradiate the UV intensity when the film was left outdoors for one year with an ultraviolet irradiator. If it exceeds 5%, the product value is inferior when used as a wallpaper for interior materials, which is not preferable.

The total light transmittance of the polypropylene film is 10% or more, preferably 10% to 40%. When the total light transmittance is within this range, it is preferable that a picture or characters printed on the base material can be seen in a matte shape from the film side. If the total light transmittance exceeds 40%, the whiteness becomes 60% or less, which is not preferable.
The wallpaper of the present invention is a laminate in which a polypropylene film is laminated on a substrate, and there are an adhesive method and a thermocompression bonding method for laminating a polypropylene film and a substrate. The whiteness of the wallpaper of the present invention in which the polypropylene film is laminated is required to be 60% or more, more preferably 70% or more, and 100%. It is preferable to be close. When the whiteness is 60% or more, the transferred wallpaper pattern or the printed pattern becomes clear and the design is enhanced, which is preferable. If the degree of whiteness is less than 60%, the transferred wallpaper pattern or the printed pattern becomes unclear, and the design is lowered. Therefore, it is not preferable because it is necessary to perform white background printing or the like on the film surface.

  The embossing rate of the wallpaper of the present invention in which the polypropylene film is laminated is required to be 10% or more, and the range of 12 to 30% makes the transferability of the uneven depth of the wallpaper pattern plate good. Workability is also improved, which is preferable. In practice, it is often embossed after the film is laminated on the base material. If the embossing rate of the wallpaper is less than 10%, the embossing temperature is increased or the speed is decreased to increase the embossing rate. Since it is necessary, the productivity is inferior, and the dimensional change of the wallpaper is increased, and the appearance is also inferior.

Moreover, the cushion ratio of the wallpaper needs to be 15% or more, and the range of 18 to 25% is good for the transfer from the wallpaper pattern plate, and the feel of the obtained wallpaper is also good. Since it is excellent, it is more preferable. If the cushion rate is less than 15%, the embossability is inferior and the feel of the obtained wallpaper is also unfavorable.
The water vapor permeability of the wallpaper of the present invention is preferably in the range of 100 to 100,000 g / (m ² · d). If the moisture permeability is less than 100 g / m ² · d, the moisture permeability is inferior, and when internal condensation occurs, the wallpaper may deteriorate or mold may occur, which is not preferable. If the air permeability exceeds 100,000 g / (m ² · d), the wallpaper surface will soak when water or other water-based materials such as coffee or soy sauce are applied, and if the dirt is wiped with a wet cloth, the wallpaper will have water. In order to penetrate, the paper or nonwoven fabric of the base material may be hygroscopically swollen and peeled off, which is not preferable. The polypropylene film used for the wallpaper of the present invention preferably has at least one melting point at 140 to 175 ° C. from the viewpoints of film forming properties, formation of voids, cushioning properties, embossing properties, and the like. More preferably, it has at least one melting point at 142 to 172 ° C., particularly preferably 145 to 165 ° C., from the viewpoint of prevention of deformation of the hole during processing and the like and film forming property. When all melting temperatures are 140 or less, voids may be blocked by heat applied to the film during processing and the like, and the cushion rate and embossing rate may decrease. If all melting temperatures exceed 175 ° C, The sheet is easily torn and the film forming property may be deteriorated. Further, the flexibility is deteriorated, and it is not preferable because a crease may be formed when the wallpaper is wound on a roll or when the wallpaper is applied to a wall.

  Further, the polypropylene film preferably has at least two melting points from the viewpoint of void formation efficiency, and further has at least one melting point in the range of 140 to 160 ° C and 160 to 175 ° C, respectively. It is particularly preferable to have at least one melting point in the range of 142 to 155 ° C and 163 to 172 ° C.

  The melting point means that a polypropylene film is heated to 250 ° C. at a rate of 10 ° C./min for 5 minutes under a nitrogen atmosphere in accordance with a method for measuring the transition heat of plastic (JIS K7122). After cooling to 10 ° C. at a cooling rate of 10 ° C./min and increasing the temperature again at a rate of 10 ° C./min, the endothermic peak that appears as the resin melts in the second temperature increase. Refers to peak temperature.

  The polypropylene resin having a melting point of at least one melting point of 140 to 175 ° C. is homopolypropylene or propylene and a second component other than propylene, such as ethylene or α-olefin, butene, hexene, octene, etc. ~ 15 wt% random or block copolymerized.

  Moreover, the following elastomer component can also be added to the said polypropylene resin. As linear low density polyethylene (LLDPE), very low density polyethylene (V-LDPE), ethylene-α-olefin copolymer, ethylene-butene rubber (EBR), ethylene-propylene rubber (EPR), propylene-butene rubber (PBR), Ethylene vinyl acetate (EVA), ethylene-ethacrylate (EEA), ethylene-methyl methacrylate (EMMA), ethylene-propylene-diene copolymer (EPDM), isoprene rubber (IR), styrene copolymer as styrene-butadiene Add 1 to 15 wt% of rubber (SBR), hydrogenated styrene rubber (H-SBR), styrene-butylene-styrene copolymer (SBS), styrene-ethylene-butylene-styrene copolymer (SEBS), etc. To do Flexibility is imparted to beam, the higher the cushion factor and embossing rate, also permeable and moisture permeability preferably improved. If the copolymerization amount and the addition amount are less than 1% by weight, the effect of addition is not observed. If the amount exceeds 15% by weight, poor dispersion occurs, gel-like protrusions are formed, heat resistance is reduced, and the heat shrinkage ratio is large. Since it may become, it is not preferable. Among these, linear low density polyethylene (LLDPE) or very low density polyethylene (V-LDPE) obtained using a metallocene catalyst is particularly preferable. Specific examples of the mVLDPE include “Engage” (type names: 8411, 8452, 8100, etc.) manufactured by DuPont Dow Elastomers. The addition amount is preferably in the range of 1 to 10% by weight. The polypropylene film of the wallpaper of the present invention preferably has a breaking strength in the MD direction and TD direction in the range of 30 to 300 MPa, respectively. More preferably, it is in the range of 50 to 250 MPa because both mechanical strength and flexibility can be achieved. If the breaking strength is less than 30 MPa, the film is likely to be broken due to the tension in the processing step, which may cause problems in process passability and enforceability, and if the breaking strength exceeds 300 MPa, it may be inferior in wallpaper cutting performance. It is not preferable.

  Moreover, it is preferable that the thermal contraction rate at the time of 120 degreeC and a 5-minute heating of this polypropylene film is 10% or less in both MD direction and TD direction. If the thermal shrinkage rate exceeds 10%, wrinkles are likely to occur during lamination with the substrate, and the wallpaper may be curled.

  It is preferable that the β crystal ratio of the polypropylene resin having the melting temperature in the range of 140 to 175 ° C. is 25% or more. When the β crystal ratio is 25% or more, by controlling the film forming conditions in the manufacturing process, β crystal is generated in the unstretched sheet, and the β crystal is changed to α crystal in the subsequent stretching process. Therefore, a uniform and dense void can be formed due to the difference in crystal density. If the β crystal ratio of the polypropylene resin is less than 25%, void formation is insufficient, the porosity of the film is low, the cushion rate and the embossing rate are lowered, and the Gurley air permeability is high, that is, the air permeability is low. Therefore, it is not preferable. The upper limit of the β crystal ratio is not particularly limited as long as the effects of the present invention are exhibited, but it is preferably 90% or less from the viewpoint of both improvement in moisture permeability and air permeability due to improved void formation and break strength. .

Here, the β crystal ratio of the polypropylene in the polypropylene film of the wallpaper of the present invention is determined by a scanning differential calorimeter (DSC) in accordance with a plastic transition heat measurement method (JIS K7122). In a nitrogen atmosphere, a 5 mg sample was heated to 250 ° C. at a rate of 10 ° C./min and held for 5 minutes, then cooled to 10 ° C. at a cooling rate of 10 ° C./min, and again at a rate of 10 ° C./min. When the temperature is raised again, the heat of fusion (ΔHu-1) of the endothermic peak that appears by melting one or more β-crystals derived from polypropylene having a peak in the range of 140 ° C. or more and less than 160 ° C., From the heat of fusion (ΔHu−2) of the endothermic peak that appears by melting one or more crystals derived from polypropylene other than the β crystal having a peak at 160 ° C. or higher, the following formula:
β crystal ratio (%) = {ΔHu−1 / (ΔHu−1 + ΔHu−2)} × 100.
Is obtained by

  In order to increase the β crystal ratio of the polypropylene resin forming the polypropylene film to 25% or more, it is preferable to add a β crystal nucleating agent to the following polypropylene resin, and the amount added depends on the effect of the β crystal nucleating agent. A range of 01% to 2% by weight is preferred. If the added amount is less than 0.01% by weight, it is difficult to make the β crystal ratio 40% or more, and if it is 2% by weight or more, the effect is balanced, and 2% by weight or less is preferable from the viewpoint of economy.

Examples of the β crystal nucleating agent that can be preferably added to the polypropylene resin constituting the polypropylene film of the present invention include carboxylic acids represented by potassium 1,2-hydroxystearate, magnesium benzoate, magnesium succinate, magnesium phthalate and the like. Alkali or alkaline earth metal salt of N; N'-dicyclohexyl-2,6-naphthalene Amide compound represented by dicarboxamide, etc .; Aromatic sulfonic acid represented by sodium benzenesulfonate, sodium naphthalenesulfonate, etc. Compounds; Di- or triesters of dibasic or tribasic carboxylic acids; Tetraoxaspiro compounds; Imidocarboxylic acid derivatives; Phthalocyanine pigments typified by phthalocyanine blue; quinacridone, quinacridone quinone, etc. Quinacridone pigments, such as, but are not limited to, binary compounds composed of component A which is an organic dibase and component B which is an oxide, hydroxide or salt of a Group IIA metal of the periodic table. However, only one type may be used, or two or more types may be mixed and used. The β crystal nucleating agent added to the polypropylene resin constituting the polypropylene film of the present invention is represented by the following chemical formula among the above, and is represented by N, N′-dicyclohexyl-2,6-naphthalene dicarboxamide and the like. Amide compounds,
R2-NHCO-R1-CONH-R3
[Wherein R1 represents a saturated or unsaturated aliphatic dicarboxylic acid residue having 1 to 24 carbon atoms, a saturated or unsaturated alicyclic dicarboxylic acid residue having 4 to 28 carbon atoms, or 6 carbon atoms. Represents an aromatic dicarboxylic acid residue having ˜28, and R2 and R3 are the same or different cycloalkyl groups having 3 to 18 carbon atoms, cycloalkenyl groups having 3 to 12 carbon atoms, or derivatives thereof. ]
R5-CONH-R4-NHCO-R6
[Wherein, R4 in the formula represents a saturated or unsaturated aliphatic diamine residue having 1 to 24 carbon atoms, a saturated or unsaturated alicyclic diamine residue having 4 to 28 carbon atoms, or 6 to 12 carbon atoms. A heterocyclic diamine residue or an aromatic diamine residue having 6 to 28 carbon atoms, wherein R5 and R6 are the same or different cycloalkyl groups having 3 to 12 carbon atoms, cycloalkenyl groups having 3 to 12 carbon atoms, or these Is a derivative of ]
A two-component compound comprising component A which is an organic dibase and component B which is an oxide, hydroxide or salt of a Group IIA metal of the periodic table can increase the porosity of the resulting polypropylene film, and the cushion rate And the embossing rate and permeability can be improved.

  Specific examples of such particularly preferable β crystal nucleating agent or β crystal nucleating agent-added polypropylene include β crystal nucleating agent “NJESTER” (type name: NU100, etc.) manufactured by Shin Nippon Rika Co., Ltd., β crystal nuclei manufactured by SUNOCO. An additive-added polypropylene “BEPOL” (type name: B022-SP etc.) and the like can be mentioned.

  The isotactic index (II) of the polypropylene resin (hereinafter sometimes abbreviated as β-crystal PP) is 90% or more, preferably 95% or more, so that the film formation stability and the mechanical strength of the film are high. This is preferable. The melt flow rate (MFR) is preferably in the range of 1 to 20 g / 10 min (230 ° C., 2.16 kg) from the viewpoints of extrusion moldability and gas / moisture permeability.

  For the polypropylene resin, known additives such as antioxidants, heat stabilizers, antistatic agents, slip agents, antiblocking agents, fillers, weathering agents, flame retardants, negative ion generators, etc. You may make it contain in the grade which does not reduce a characteristic. Among them, it is preferable to contain a small amount of at least one kind of organic lubricant, inorganic particles, and organic particles in order to impart easy slipping and improve process passability. However, the addition amount at this time is preferably 5% by weight or less, more preferably 3% by weight or less. If the added amount exceeds 5% by weight, the organic lubricant and particles may fall off in the film forming process and the lamination process with the base material, and the process may be soiled, and the skin may be stimulated by the alkalinity or acidity of the film surface. Since it may be, it is not preferable.

  Examples of the organic lubricant include amide compounds such as stearamide, erucamide, erucamide, stearyl erucamide, or a mixture thereof.

  Examples of inorganic particles include wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, magnesium carbonate, zinc carbonate, titanium oxide, zinc oxide (zinc white), antimony oxide, and oxidation. Cerium, zirconium oxide, tin oxide, lanthanum oxide, magnesium oxide, barium carbonate, zinc carbonate, basic lead carbonate (lead white), barium sulfate, calcium sulfate, lead sulfate, zinc sulfide, mica, titanium mica, talc, clay, Kaolin, lithium fluoride, calcium fluoride, and the like can be used.

  The organic particles are particles obtained by crosslinking a polymer compound using a crosslinking agent. For example, crosslinked particles of polymethoxysilane compounds, crosslinked particles of polystyrene compounds, crosslinked particles of acrylic compounds, crosslinked particles of polyurethane compounds, crosslinked particles of polyester compounds, crosslinked particles of fluorine compounds, or a mixture thereof Can.

  It is preferable that the inorganic particles and the crosslinked organic particles have a spherical shape and have an average particle diameter in the range of 0.5 to 4 μm because the aggregation of the particles is small and the lubricity effect is high. If the average particle size is less than 0.5, the slippery effect is low, and if it exceeds 0.4 μm, excessive voids are likely to be formed, and the air permeability, cushion rate, and embossing rate are reduced, particle dropout or rubbing between films. It is not preferable because the film surface is easily scratched.

  The polypropylene resin preferably contains 3 to 20% by weight of fine particles having an average particle size in the range of 0.06 to 0.4 μm. By incorporating fine particles having an average particle diameter of 0.06 to 0.4 μm in a polypropylene resin having a β crystal ratio of 25% or more, the porosity of the biaxially stretched film is improved to, for example, 40% or more. Air permeability and whiteness are also improved.

  The fine particle content in the polypropylene resin having an average particle size in the range of 0.06 to 0.4 μm is preferably in the range of 3 to 20% by weight. If the particle content is less than 3% by weight, the number of voids formed by the presence of particles is small, and the effect of addition may not be obtained. Conversely, if the particle content exceeds 20% by weight, the effect of containing particles Not only becomes saturated, but film tearing is likely to occur during film production. The content of the fine particles is preferably 5 to 15% by weight, more preferably 7 to 10% by weight.

  In the present invention, the method of adding fine particles to the polypropylene film is not particularly limited, and a predetermined amount of inorganic fine particles or organic fine particles are directly added to the polypropylene resin, mixed and melt extruded at the time of film production. However, from the viewpoints of preventing process contamination due to the scattering of fine particles, the dispersibility of the particles, the uniformity of the final film characteristics, the productivity, etc., the fine particles in the polypropylene resin are higher than the final film in advance. Use a masterbatch method that prepares a masterbatch that is added and mixed at a concentration and then compounded using a twin-screw extruder, and is diluted to a predetermined concentration using a resin with no particles added during film production. Is preferred. Here, the particle concentration in the masterbatch is preferably 30 to 70% by weight, and if it is 45 to 65% by weight, it is particularly preferable from the viewpoint of particle dispersibility and economy.

  Moreover, it is preferable that the polypropylene film obtained as mentioned above has β crystal activity.

  Furthermore, it is possible to add a high melt tension polypropylene resin (HMS-PP) to a polypropylene resin having a melting temperature in the range of 140 to 175 ° C. with a β crystal ratio of 25% or more. The cushion ratio, embossing ratio, air permeability, and moisture permeability can be easily controlled within the range of the present invention.

  As a method for obtaining HMS-PP, for example, a method of blending a polypropylene resin containing a large amount of a high molecular weight component, a method of blending an oligomer or polymer having a branched structure, as described in JP-A No. 62-121704. In addition, a method of introducing a long chain branching structure into a polypropylene molecule, or as described in Japanese Patent No. 2869606, melt tension and intrinsic viscosity, crystallization temperature and melting point without introducing long chain branching A method of making a linear crystalline polypropylene satisfying a specific relationship and having a boiling xylene extraction residual ratio in a specific range is preferably used.

  Among these HMS-PPs, it is particularly preferable to use polypropylene having a long chain branch in the main chain skeleton. The polypropylene having a long chain branch in the main chain skeleton is a polypropylene resin having a branched polypropylene chain having a length equivalent to the main chain from the polypropylene main chain skeleton.

  Examples of the high melt tension polypropylene resin include “HMS-PP” (type names: PF-814, PF-633, PF-611, SD-632, etc.) manufactured by Basell, and “Daploy” (manufactured by Borealis) ( Type name: WB130HMS, etc.), “Inspire” type names manufactured by Dow, Inc .: D114, D201, D206, etc.). The MFR of the high melt tension polypropylene resin is preferably in the range of 1 to 20 g / 10 min because of its high effect.

  Although the amount of HMS-PP described above depends on the type of HMS-PP used, it is preferably 1 to 20% by weight, and the effect is seen even when added in a small amount. If the addition amount is less than the above range, the film-forming property is not improved, and if it exceeds the above-mentioned range, the film-forming property is deteriorated. The stable extrudability of the molten polymer during extrusion and the smoothness of the film may deteriorate, and the amount of HMS-PP added is more preferably 1 to 15% by weight, and most preferably 2 to 10% by weight.

  The polypropylene film of the wallpaper of the present invention is preferably stretched at least uniaxially, more preferably biaxially stretched to form voids inside the film, increasing the cushion rate and embossing rate, In addition, air permeability and moisture permeability are improved, which is preferable.

  As the biaxial stretching method, there are a sequential biaxial stretching method, a simultaneous biaxial stretching method, and a tubular stretching method. However, the sequential biaxial stretching method is preferable from the viewpoint of economical efficiency and obtaining a film having a uniform thickness.

  The thickness of the polypropylene film of the present invention is preferably in the range of 10 to 100 μm, particularly in the range of 20 to 70 μm because both mechanical strength, cushioning and embossing properties, and air permeability and moisture permeability can be achieved. If the film thickness is less than 10 μm, the mechanical strength is lowered, the film is stretched by the tension at the time of laminating on the base material, and the film is easily broken. If the film thickness exceeds 100 μm, the wallpaper is stiff and bulky, and is inferior in handleability.

  The polypropylene film of the wallpaper of the present invention has a structure of two or more layers in which the polypropylene film is a core layer and a skin layer is laminated on at least one side of the core layer, and the porosity of the skin layer is lower than the porosity of the core layer. It is preferable. It is preferable that the skin layer having a low porosity is composed of two or more layers provided on at least one side of the core layer, since it is difficult to cleave and torn easily. Here, the cleaving of the film refers to a phenomenon in which the film is split into a plurality of sheets approximately parallel to the surface.

  The skin layer has a porosity of 70% or less, preferably 10 to 60%. Here, the porosity of the skin layer is a ratio of voids in the skin layer when a film cross section adjusted under specific conditions is observed with SEM under specific conditions as described below. If the porosity of the skin layer exceeds 70%, it may be easily cleaved and the adhesion to the substrate may be reduced. If the porosity of the skin layer is less than 10%, the whiteness, cushioning ratio, embossing Any of the characteristics of rate and air permeability may be out of the scope of the present invention, which is not preferable.

  The thickness of the polypropylene film when the skin layer and the core layer are composed of two or more layers is such that the thickness of the skin layer is 1/3 or less, preferably 1/5 or less of the total film thickness. It is preferable because the characteristics of the present invention can be exhibited.

  The resin composition of the skin layer is preferably the same composition as the core layer resin of the polypropylene film.

  In order to obtain the above-mentioned characteristics of the polypropylene film of the present invention when the polypropylene film has a skin layer and a core layer of two or more layers, it preferably has β crystal activity. Since the polypropylene film of the present invention has β crystal activity, in the production process, by controlling the film forming conditions, β crystal is formed in an unstretched sheet having two or more layers of a skin layer and a core layer. In the subsequent stretching step, the β crystal is transformed into the α crystal, and a uniform and dense void can be formed due to the difference in crystal density.

  Here, in the present invention, determination is made according to the following criteria in correspondence with the fact that the entire polypropylene film has β crystal activity. That is, using a differential scanning calorimeter (DSC), a 5 mg white film was heated to 280 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere according to JIS K 7122 (1987), and then held for 5 minutes. After cooling to 30 ° C. at a cooling rate of 10 ° C./minute, holding for 5 minutes and then raising the temperature again at a rate of 10 ° C./minute, the melting of β crystals from 140 to 160 ° C. If there is an accompanying endothermic peak and the heat of fusion calculated from the peak area of the endothermic peak is 10 mJ / mg or more, the white film is defined as having β-crystal activity (as a whole film). In addition, hereinafter, the calorific curve obtained by the first temperature increase may be referred to as a first run caloric curve, and the caloric curve obtained by the second temperature increase may be referred to as a second run caloric curve.

  Here, Cho et al., “Polymer”, 44, p. 4053-4059 (2003); Takahashi et al., “Molding”, 15, p. As disclosed in 756-762 (2003) and the like, the ability to form β crystals of polypropylene can be confirmed using DSC. In these documents, a calorimetric curve is collected using DSC under temperature conditions close to the above, and the β crystal activity of polypropylene containing a β crystal nucleating agent is confirmed. Here, “having β-crystal activity” means that a β-crystal can be generated when polypropylene is crystallized. In addition, the determination of the β crystal activity here is performed on the film after the extrusion, casting, stretching, and winding processes, that is, after film formation. Therefore, even when the A layer contains a β crystal nucleating agent as exemplified below, the β crystal activity is determined for the entire film including the A layer.

In addition, although there is an endothermic peak in the above temperature range, in cases where it is unclear whether it is caused by the melting of the β crystal, in addition to the DSC result, the sample was melt crystallized under the following specific conditions, Using the wide-angle X-ray diffraction method, it is determined that “having β crystal activity” based on the presence of a diffraction peak of (300) plane observed near 2θ = 16 ° due to β crystal and the following K value. Also good. That is, the diffraction peak of the (300) plane (referred to as Hβ ₁ ) observed near 2θ = 16 ° due to the β crystal and the vicinity of 2θ = 14, 17, 19 °, respectively, and due to the α crystal ( 110), (040), and (130) plane diffraction peak intensities (referred to as Hα ₁ , Hα ₂ , and Hα ₃ respectively), the K value calculated by the following formula is 0.3 or more, more preferably It may be determined that “having β crystal activity” when it is 0.5 or more. Here, the K value is an empirical value indicating the ratio of β crystals. For details of the K value, such as the calculation method of each diffraction peak intensity, refer to A. Turner Jones et al., “Macromoleculare Chemie”, 75, pages 134-158 (1964). Good.

K = Hβ ₁ / {Hβ ₁ + (Hα ₁ + Hα ₂ + Hα ₃ )}
(However, Hβ ₁ : (300) plane diffraction peak intensity attributed to polypropylene β crystal, Hα ₁ , Hα ₂ , Hα ₃ : (110), (040), (130 attributed to polypropylene α crystal, respectively. ) Diffraction peak intensity of surface)
Moreover, in order to form the void of the above aspect in the skin layer, it is important to set the metal drum temperature at the time of manufacturing the unstretched sheet to a high temperature of about 100 to 130 ° C. in the manufacturing process. However, in order to promote the formation of voids, incompatible resins, inorganic particles, organic particles and the like exemplified below may be added to the polypropylene constituting the skin layer. Here, the addition of these may be effective not only in promoting the formation of voids but also in improving the slipperiness by forming fine irregularities on the film surface.

  The incompatible resin that can be preferably added to the skin layer is not particularly limited. For example, polymethylpentene, cyclic polyolefin, polycarbonate, polysulfone, polyarylate, isotactic polystyrene, syndiotactic polystyrene, polymethyl methacrylate, and saturated polyester. And at least one resin selected from liquid crystal resin (LCP) and the like. As the incompatible resin used for the skin layer of the polypropylene film of the present invention, polymethylpentene is particularly used from the viewpoints of handling property, production cost (raw material price), dispersibility in polypropylene, formation of fine pores, and the like. Particularly preferred.

  Examples of the inorganic particles include wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, magnesium carbonate, zinc carbonate, titanium oxide, zinc oxide (zinc white), and antimony oxide. , Cerium oxide, zirconium oxide, tin oxide, lanthanum oxide, magnesium oxide, barium carbonate, zinc carbonate, basic lead carbonate (lead white), barium sulfate, calcium sulfate, lead sulfate, zinc sulfide, mica, mica titanium, talc, Clay, kaolin, lithium fluoride, calcium fluoride, and the like can be used.

  Organic particles are particles obtained by crosslinking a polymer compound using a crosslinking agent. For example, crosslinked particles of polymethoxysilane compounds, crosslinked particles of polystyrene compounds, crosslinked particles of acrylic compounds, crosslinked particles of polyurethane compounds, crosslinked particles of polyester compounds, crosslinked particles of fluorine compounds, or a mixture thereof Can be mentioned.

  It is preferable that the inorganic particles and the crosslinked organic particles have a spherical shape and have an average particle diameter in the range of 0.5 to 4 μm because the aggregation of the particles is small and the lubricity effect is high. When the average particle size is less than 0.5 μm, the slippery effect is low, and when it exceeds 4 μm, excessive voids are easily formed, and the air permeability, the cushion rate, the embossing rate are reduced, the particles fall off or the films are rubbed together This is not preferable because the film surface is easily damaged.

  Next, it is preferable that the base material used for the wallpaper of this invention consists of at least 1 sort (s) of a nonwoven fabric, paper, and the plastic film which has a through-hole.

  As the nonwoven fabric, one or more kinds of polyester fibers such as polyethylene terephthalate and polytrimethylene terephthalate, polyacrylic fibers, polypropylene fibers, polyamide fibers such as nylon 6 and nylon 66, semi-synthetic fibers such as acetate fibers, etc. Nonwoven fabrics that are combined can be mentioned.

  Nonwoven fabric manufacturing methods include wet nonwoven fabrics in which fibers and pulp or adhesive fibers are made into a sheet by a papermaking method, dry pulp nonwoven fabrics in which pulverized pulp is bonded with an adhesive or adhesive fibers, dry nonwoven fabrics in which fibers are made into a sheet by a card method, and spinning. There are spunbond nonwoven fabrics that are directly bonded and bonded by self-adhesion, melt blown nonwoven fabrics of ultra-fine fiber sheets that are extruded with high pressure and blown off with hot air, and flash spinning nonwoven fabrics that melt the polymer with a solvent and spin at high pressure. A spunbonded nonwoven fabric is preferred.

Further, the basis weight of the nonwoven fabric is preferably in the range of ^{20 to} 500 g / m ² , more preferably 40 to 300 g / m ² , since both air permeability and moisture permeability and waterproofness can be achieved. The fiber diameter at this time is preferably 1 to 10 dtex (1 dtex = weight of a 10,000 m-long yarn is 1 g), since the above-mentioned weight range can be achieved.

  Further, the paper may be in the form of a sheet having air permeability, and is usually a cardboard generally used as a backing material for wallpaper, and has a specific gravity in the range of 0.3 to 1.2. Good handleability. Furthermore, flame retardants and base papers containing inorganic substances such as aluminum hydroxide and calcium hydroxide can be used.

  Examples of the plastic film having a through hole include a film having a hole formed with a needle, a laser beam, or the like, and a film having a hole formed by adding a large amount of inorganic or organic particles.

The thickness of the substrate of the present invention is preferably in the range of 50 to 500 μm. This thickness refers to the thickness at a load of 23.5 kpa (240 g / m ² ) described in JIS L 1096. If the thickness of the substrate is less than 50 μm, it is easily broken during pulling or rubbing, and if it exceeds 500 μm, the substrate becomes bulky and inferior in winding and handling properties, and the preferred thickness is in the range of 100 to 300 μm.

  As a method of laminating the polypropylene film and the base material, there are an adhesive method, a heat fusion method, a hot melt coating method, a laser method, an ultrasonic adhesion laminating method, etc., but it has a wide workability and dimensional stability. In this respect, the adhesive method or the hot melt coating method is preferable. At this time, it is preferable to use point bonding or line bonding since the decrease in air permeability and moisture permeability is small.

  Examples of the adhesive resin include acrylic resins such as ethylene-acrylic acid copolymers, ethylene / acrylic acid ester copolymers, ethylene-methacrylic acid copolymers, and ethylene-methacrylic acid ester copolymers. it can. An example is “Zyxen” manufactured by Sumitomo Seika Co., Ltd.

  The polyester-based resin is preferably an aromatic polyester, and examples of the polyurethane-based resin include ionomer-type polyether-based urethanes and polyester-based urethane copolymers. For example, “Hydran” manufactured by Dainippon Ink Industries, Ltd. may be mentioned.

  Examples of the ionomer resin include those obtained by graft-polymerizing ethylene and a hydrophilic group such as sodium or potassium into an aqueous dispersion.

  Further, as a hot melt adhesive, there is a polyol-urethane reactive hot melt adhesive. This adhesive is preferable in terms of productivity because the drying and curing time is as fast as several seconds to several dozens.

  Examples of coating techniques include knife over roll coaters, reverse roll coaters, gravure coaters, rod coaters, air doctor coaters, hot melt coaters, or other known coating devices, but in this application, coating is used. A knife over roll coater method or a hot melt coater method is preferred in view of productivity because a coating agent having a large thickness and a high solid content concentration is applied.

  Next, although an example is demonstrated about the manufacturing method of the wallpaper of this invention, this invention is not limited only to this example.

  As a polypropylene film of the wallpaper of the present invention, a polypropylene resin having a β crystal ratio of 25% or more is supplied to an extruder heated to 180 to 300 ° C., melted, and extruded by a T-die die to obtain a molten sheet. obtain. This molten sheet is extruded and brought into close contact with a drum maintained at a surface temperature of 100 to 130 ° C., and is cooled and solidified by blowing air of 30 to 130 ° C. from the non-drum surface to produce an unstretched film. When laminating a skin layer, a polypropylene resin having a β crystal ratio of 25% or more is supplied to another extruder heated to 180 to 300 ° C. and melted to laminate two or three layers. Extrusion molding is performed using a T die die, and a molten sheet is obtained. At this time, since the drum temperature is high, the porosity of the film after biaxial stretching is increased, and the air permeability and moisture permeability are improved. At this time, in order to make the porosity of the skin layer lower than that of the core layer, it can be adjusted by blowing cool air onto the surface of the skin layer to make it lower than the resin temperature of the core layer. Next, in order to increase the void formation and the through-hole property inside the film, the unstretched film is guided to a roll group or an oven heated to 80 to 140 ° C., and after the film temperature is set to 80 to 140 ° C., the surface temperature A pair of nip rolls (stretching rolls) of a hard chrome-plated metal roll and a rubber roll kept at 60 to 130 ° C., and a pair of nip rolls of a hard chrome-plated metal roll and a rubber roll kept at a surface temperature of 30 to 130 ° C. It passes between (cooling rolls), stretches 3 to 7 times in the MD direction (longitudinal direction, i.e., the traveling direction of the film) by the peripheral speed difference between the stretching rolls and the cooling rolls, and cools in a roll group of 30 to 120C. Subsequently, both ends of the film stretched in the MD direction are guided to a tenter while being gripped with clips, and the direction perpendicular to the longitudinal direction (lateral direction) in an atmosphere heated to 120 to 160 ° C. (film temperature: 100 ° C. to 150 ° C.) ) To 6 to 12 times. The area ratio (longitudinal stretch ratio × lateral stretch ratio) is preferably 24 to 84 times, and preferably 30 to 50 times from the viewpoint of film formation stability. If the area magnification is less than 24 times, the obtained film has low air permeability and moisture permeability, and the F5 value is too low to obtain the characteristics of the film of the present invention. Conversely, if the area magnification exceeds 84 times, the film is broken during stretching. Tends to occur, and the breaking strength tends to decrease. In order to complete the crystal orientation of the biaxially stretched film thus obtained and to impart flatness and dimensional stability, it is subsequently subjected to heat treatment at 140 to 170 ° C. for 5 to 20 seconds in the tenter, and thereafter The wallpaper polypropylene film of the present invention can be obtained by uniform cooling and then cooling to room temperature and winding. During the heat treatment, a relaxation treatment of 3 to 10% may be performed in the horizontal direction or the vertical direction as necessary. Further, after biaxial stretching, it may be re-stretched in either the longitudinal or transverse direction. The surface of the polypropylene film of the wallpaper of the present invention thus obtained is subjected to corona discharge treatment in air or in one or more atmospheres of nitrogen gas and carbon dioxide gas in order to be bonded to the base material. It is preferable to take up with a wetting tension of 35 mN / m or more.

  Next, a nonwoven fabric or cardboard was used as the substrate. As a method of laminating the base material and the polypropylene film, an adhesive is coated on the polypropylene film at an interval of 2 cm with a width of 5 mm and a thickness of 10 to 30 μm, dried at 120 to 130 ° C. for 1 minute, overlapped with the base material, and 100 to 140 ° C. After pressing and laminating at a linear pressure of 5 to 15 kg / cm between a metal roll and a rubber roll heated to 140 ° C. for 1 minute, wallpaper was obtained.

[Measurement and evaluation method of characteristics]
The characteristic value of this invention is calculated | required with the following evaluation method and evaluation criteria.
-Whiteness Whiteness is the X value and Y value which are tristimulus values of color, using a spectroscopic color difference meter SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd. according to optical conditions according to JIS Z-8722. The Z value was measured and determined by the following formula: whiteness (%) = 4 × 0.847 × Z value−3 × Y value.
・ Cushion ratio Dial gauge thickness gauge (JIS B 7503 (1997), UPAIGHT DIAL GAUGE (0.001 × 2 mm), No. 25, measuring element 5 mmφ flat type) manufactured by PEACOCK is used as a dial gauge stand (No. 7001DGS- M). The film thickness obtained from this or the thickness (d0) of the wallpaper obtained by laminating the film on the substrate is measured. Further, the thickness (d500) when a load of 500 gf was applied to the dial gauge pressing portion was measured, and the cushion rate was calculated by the following formula (unit:%). At this time, about the wallpaper which laminated | stacked the film, thickness is measured by making a film side into a measuring element.

Cushion rate (%) = {(d0−d500) / d0} × 100
The same measurement was performed 5 times for the same sample, and the average value of the obtained cushion rates was defined as the cushion rate of the sample.

(3) Embossing rate A film or a wallpaper on which a film is laminated is heated to 120 ° C. at a depth of 300 μm, passed through a 0.4 mm square stamping roll and a paper roll at a speed of 1 m, and then pressurized at a pressure of 200 MPa. Then, it was cooled by passing through a cooling roll and embossed. The thickness before and after the embossing was set on a dial gauge stand (No. 7001DGS-M), a dial gauge type thickness meter (JIS B 7503 (1997), PURICOCK UPRIIGHT DIAL GAUGE (0.001 × 2 mm), No .25, measuring element 5 mmφ flat type), and the embossing rate was obtained by the following formula.

Embossing rate (%): {(d−d0) / 300} × 100
d: Thickness after embossing (μm), d0: Thickness before embossing (μm), Marking depth: 300 μm
The same measurement was performed five times for the same sample, and the average value of the obtained embossing rates was defined as the embossing rate of the sample.

(4) Gurley air permeability Measured with a B-type densometer (manufactured by Toyo Seiki Co., Ltd.) according to JIS P 8117, and obtained by converting to a thickness of 25 μm. The smaller the Gurley value (sec / 100 cc), the better the air permeability.

(5) Moisture permeability The moisture permeability (unit: g / (m ² · d)) of the cloth and film is measured according to the cup method (A-1 method: calcium chloride) prescribed in JIS L 1099, The thickness was calculated in terms of 25 μm. The higher the moisture permeability, the better the moisture permeability.

(6) Color-change rate The film or wallpaper is irradiated with ultraviolet rays using an iSuper UV tester (SUV-W131 type) manufactured by Iwasaki Electric Co., Ltd., and the whiteness before and after the ultraviolet irradiation is measured by the whiteness measurement method described above. Then, the change rate of the whiteness was determined as the color change resistance rate, and was obtained by the following formula.
UV irradiation intensity: 100 mW / cm ² , treatment environment: 60 ° C., 50% RH, irradiation time: 24 hours Color change rate (%) = {(whiteness before irradiation−whiteness after irradiation) / before irradiation Whiteness} × 100
(7) Isotactic index (II) boiling n-heptane extraction residue The isotactic index (II) is determined from the boiling n-heptane extraction residue. The sample is extracted with boiling n-heptane for a certain period of time, and the weight (%) of the portion not extracted is calculated to calculate the isotactic index.

  Specifically, after drying the cylindrical filter paper at 110 ± 5 ° C. for 2 hours and leaving it in a constant temperature and humidity room for 2 hours or more, put 10 g of the sample (powder or flakes) into the cylindrical filter paper, and put a weighing cup and tweezers Use a precision balance (up to 4 digits after the decimal point).

This is set on the top of the extractor containing 80 cc of heptane, and the extractor and the cooler are assembled. This is heated with an oil bath or an electric heater and extracted for 12 hours. Heating is adjusted so that the number of drops from the cooler is 130 drops or more per minute. The cylindrical filter paper containing the extraction residue is taken out, put in a vacuum dryer, and dried at 80 ° C. and a vacuum degree of 100 mmHg or less for 5 hours. After drying, the sample is allowed to stand for 2 hours in constant temperature and humidity, and then precisely weighed and calculated by the following formula.
Isotactic index (II) (%) = (P / Po) × 100
However, Po is the sample weight (g) before extraction, P is the sample weight (g) after extraction.

(8) MFR (melt flow rate)
Polypropylene and thermoplastic elastomer are measured according to JIS K 7210, Condition M (1995) (temperature 230 ° C., load 2.16 kg). The ethylene resin is measured in accordance with JIS K 7210, condition 4 (1995) (temperature 190 ° C., load 2.16 kg).

(9) Breaking strength in longitudinal direction (MD) and width direction (TD) of film The breaking strength was measured at 25 ° C. using Tensilon (tensile tester) manufactured by Orientec Corporation. The measurement is performed by pulling a sample having a sample width of 10 mm and a sample length of 50 mm with the longitudinal direction and the width direction of the sheet as the sample length direction at a speed of 300 mm / min in the sample length direction. The breaking strength (MPa) in the direction was measured at 10 points, and the average value in the longitudinal direction and the width direction was added to obtain the sum.

(10) Porosity The porosity of the film was determined by substituting a sample sample obtained by cutting the sheet into a size of 30 mm × 40 mm using a high-precision electronic hydrometer SD-120L manufactured by Mirage Trading Co., Ltd. ( Ten points were measured according to JIS K-7112, Method A). The measurement was performed under conditions of a temperature of 23 ° C. and a relative humidity of 65%. Further, after measuring the apparent specific gravity (d1) of the film, the sheet was further melted and compressed by a hot press at 280 ° C. to produce a sheet completely free of pores. The apparent specific gravity (d2) of the sheet immersed in water at 0 ° C. and rapidly cooled is measured in the same manner. The porosity of the film is the following formula:
Porosity (%) = (1−d1 / d2) × 100
Determined by

(11) Porosity of skin layer Using a freeze microtome method, a cross section in the transverse direction-thickness direction of a polypropylene film was collected at -100 ° C. After coating Pt on the cross section of the obtained film, the cross section was observed using a scanning electron microscope (SEM) under the following conditions, and a cross-sectional image was collected. Sample preparation and cross-sectional observation were performed at Toray Research Center (TRC).
Apparatus: Ultra high resolution electrolytic emission scanning electron microscope (UHR-FE-SEM) S-900H manufactured by Hitachi, Ltd.
・ Acceleration voltage: 2 kV
-Observation magnification: 10,000 times.

  The skin layer was continuously observed parallel to the horizontal direction, and five cross-sectional photographs of the B layer were collected by changing the observation position.

An OHP sheet (Seiko Epson Co., Ltd. OSON-only OHP sheet) was placed on each of the obtained cross-sectional photographs. Next, only voids (voids) of the skin layer were painted black with a magic pen on the OHP sheet. Using the obtained image of the OHP sheet, analysis was performed in the same manner as in (1) above, and the total area of the skin layer observed (the thickness of the skin layer × actual size observed in the lateral direction), that is, the rectangular object to be measured The ratio of the void (area painted black) to the total area of the region (Rectangular AOI) is calculated as a percentage and used as the porosity of the skin layer (unit:%)
(12) β-crystal ratio Polypropylene resin and polypropylene film using a differential thermal calorimeter RDC220 (DSC) manufactured by Seiko Denshi Kogyo Co., Ltd., in accordance with a method for measuring the transition heat of plastic (JIS K7122), under a nitrogen atmosphere 5 mg sample was heated to 250 ° C. at a rate of 10 ° C./min and held for 5 minutes, then cooled to 10 ° C. at a cooling rate of 10 ° C./min, and again heated at a rate of 10 ° C./min. When the temperature rises again, the heat of fusion (ΔHu-1) of the endothermic peak that appears by melting one or more β-crystals derived from polypropylene having a peak in the range of 140 ° C. or more and less than 160 ° C., and 160 ° C. The heat of fusion (ΔHu-2) of the endothermic peak that appears by melting one or more crystals derived from polypropylene other than the β crystal having the above peak is measured. The β crystal ratio is expressed by the following formula:
β crystal ratio (%) = {ΔHu−1 / (ΔHu−1 + ΔHu−2)} × 100
Determined by

(13) Confirmation of β crystal activity
[Confirmation of the entire film]
Measurement was performed based on JIS K 7122 (1987) using a Seiko Instruments thermal analyzer RDC220 type. 5 mg of film (sample) was enclosed in an aluminum pan, loaded, and set in the apparatus. The temperature was raised from 30 ° C. to 280 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere (hereinafter, the caloric curve obtained at this time may be abbreviated as a first run caloric curve). After completion of the temperature increase, the system was kept at 280 ° C. for 5 minutes. Subsequently, it was cooled to 30 ° C. at a rate of 10 ° C./min. After completion of cooling, the system was kept at 30 ° C. for 5 minutes. Subsequently, the temperature was raised again to 280 ° C. at a rate of 10 ° C./min (hereinafter, the caloric curve obtained at this time may be abbreviated as a second run caloric curve). In the caloric curve of the second run obtained at this time, the film (raw material polypropylene) has β crystal activity when an endothermic peak accompanying melting of β crystal having an apex at 140 ° C. or higher and lower than 160 ° C. is observed It was determined. In addition, the endothermic peak here means that whose heat of fusion is 10 mJ / mg or more. The heat of fusion is the area enclosed by the baseline and the calorific curve until the heat curve is shifted from the baseline to the endothermic side as the temperature rises and then returns to the baseline position. A straight line was drawn on the high temperature side to the intersection of the calorific curves, and this area was determined by computer processing. If the calorimetric curve shifts to the endothermic side, does not return completely to the baseline position, and then shifts again to the endothermic side, a perpendicular line is dropped from the maximum point at which it begins to shift to the endothermic side again to the baseline. And the area surrounded by the vertical line.

  In addition, a melting peak having an apex at 140 to 160 ° C. exists in the above method, but if it is unclear whether it is caused by melting of the β crystal, a melting peak having an apex at 140 to 160 ° C. exists. And a sample prepared under the following conditions may be determined to have β crystal activity when the K value calculated from each diffraction peak intensity of the diffraction profile obtained by 2θ / θ scan is 0.3 or more. .

The measurement conditions of the wide angle X-ray diffraction method are shown below.
-Sample: After aligning the film so that the thickness of the sample after hot press adjustment is about 1 mm, the film is sandwiched between two aluminum plates with a thickness of 0.5 mm and hot pressed at 280 ° C. Then, the polymer chain was almost non-oriented by melting and compressing. Immediately after the obtained sheet was taken out together with the aluminum plate, it was crystallized by immersing in boiling water at 100 ° C. for 5 minutes, and then cooled in an atmosphere at 25 ° C., and a sample cut out from the obtained sheet was used for measurement. .
・ X-ray diffractometer: 4036A2 manufactured by Rigaku Corporation
・ X-ray source: CuKα ray (using Ni filter)
・ Output: 40kV, 20mA
・ Slit system: 2mmφ-1 ° -1 °
-Detector: Scintillation counter-Count recording device: RAD-C type manufactured by Rigaku Denki Co., Ltd.-Measuring method: 2θ / θ scan (step scan, 2θ range 10-55 °, 0.05 ° step, integration time 2 seconds ).

Here, K value is observed at around 2 [Theta] = 16 °, (a Hbeta ₁₎ diffraction peak intensity of β due to crystal (300) plane are observed respectively in the vicinity of 2θ = 14,17,19 °, From the diffraction peak intensities of the (110), (040), and (130) planes (referred to as Hα ₁ , Hα ₂ , and Hα ₃ , respectively) due to the α crystal, it can be calculated by the following mathematical formula. The K value is an empirical value indicating the ratio of β crystals. For details of the K value, such as the calculation method of each diffraction peak intensity, see A. Turner Jones et al., “Macromoleculare Chemie” (Macromoleculare Chemie). ), 75, pages 134-158 (1964).
K = Hβ ₁ / {Hβ ₁ + (Hα ₁ + Hα ₂ + Hα ₃ )}
The structure of the polypropylene crystal type (α crystal, β crystal), the obtained wide-angle X-ray diffraction profile, etc. are described in, for example, Edward P. Moore Jr. Written by "Polypropylene Handbook", Industrial Research Committee (1998), p. 135-163; Hiroyuki Tadokoro, “Structure of Polymer”, Kagaku Dojin (1976), p. 393; A. Turner-Jones et al., “Macromoleculare Chemie”, 75, p. There are a number of reports including 134-158 and references cited in these documents, which can be referred to.

  The above confirmation may be measured not only for the biaxially stretched film but also for the corresponding unstretched sheet.

In the present invention, those having β-crystal activity are indicated by ◯, and those having no β crystal activity are indicated by ×.
[Confirmation about layer B]
By the same method as described above, a calorimetric curve was collected and judged for the entire resin of the skin layer using DSC. In addition, the shape of the sample may be any as long as it is the entire resin of the skin layer, but since it is easy to handle, a chip shape is preferable. Alternatively, a sample may be prepared by scraping a required amount of the skin layer from a polypropylene film skin layer with a cutter knife or the like.

(14) Melting point melting point: Polypropylene film using Seiko Electronics Co., Ltd. scanning differential calorimeter RDC220 (DSC) according to plastic transition heat measurement method (JIS K7122), nitrogen atmosphere 5 mg sample was heated up to 250 ° C. at a rate of 10 ° C./min and held for 5 minutes, then cooled to 10 ° C. at a cooling rate of 10 ° C./min, and again heated at a rate of 10 ° C./min. At that time, the peak temperature of the endothermic peak accompanying the melting of the resin during the temperature rise was defined as the melting point (Tm).

(15) Film thickness Using a dial gauge thickness gauge (JIS B-7509, measuring element 5 mmφ flat type), 10 points were measured at 10 cm intervals in the longitudinal direction and the width direction of the film, and the average value was obtained.

(16) Base Material Thickness According to JIS L 1096, 10 points were measured at 10 cm intervals in the longitudinal direction and the width direction at a load of 23.5 KPa, and the average value was obtained.

(17) Thickness of each layer constituting wallpaper Using a cross-sectional photograph taken by magnifying the cross section of the moisture-permeable waterproof cloth 1000 times using a scanning electron microscope S-2100A type (manufactured by Hitachi, Ltd.) Then, the length of each layer in the thickness direction was measured, and the thickness of each layer was obtained by calculating backward from the magnification. In determining the thickness of each layer, a total of five cross-sectional photometers arbitrarily selected from different measurement visual fields were used, and the average value thereof was calculated.

(18) Determination of having substantially nucleus-free voids and number of voids The cross section of the film was photographed with a scanning electron microscope S-2100A type (manufactured by Hitachi, Ltd.) magnified to 8000 times. Using the cross-sectional photograph, the total voids per 100 μm ² (single bubbles having a boundary line) and voids having nuclei were counted, and the value obtained by dividing the number of voids having nuclei by the total number of voids was substantially less than 5%. In particular, it was determined to have a nuclear-free void. In addition, for the observation of voids in the film cross section, a total of 10 cross-sectional photometers arbitrarily selected from different measurement fields were used. In addition, the void nucleus means that one or more spherical or irregular incompatible resinous, inorganic or organic particles capable of forming voids in the PP of the matrix are present in a single void having one boundary line. That means.

The number of voids was determined by drawing 10 lines of 80 mm length (corresponding to a length of 10 μm) in the thickness and width directions on the above observation photograph and counting the number of layers per 100 μm ² . The layer was counted as one layer at the interface between the resin and the hole in the portion where the resin and the hole exist alternately on the line.

(19) Wetting tension (mN / m)
It measured based on the measuring method prescribed | regulated to JISK6768 using the liquid mixture of formamide and ethylene glycol monoethyl ether.

(20) Cleavage resistance Cleavage resistance refers to a phenomenon in which when a cellophane tape is applied to a film surface and then peeled off rapidly, the film is split into a plurality of pieces approximately parallel to the surface. The case where cleavage did not occur was evaluated as ◯, the case where cleavage occurred but the film was not broken at the extreme surface layer was evaluated as Δ, and the case where cleavage proceeded to the inside of the film and the film was broken was evaluated as ×.

(21) Process passability When laminating a substrate and a film, when winding up to a width of 2 m and a length of 1000 m at an oven temperature of 120 ° C. and a laminating speed of 10 m / min, to a metal roll and a rubber roll arranged in a laminating machine The state of white powder adhesion, film shrinkage, tearing, wrinkle generation, etc. was observed and evaluated as follows.

  ◯: There was no white powder adhering to the metal stretching roll, no shrinkage, tearing, or wrinkling of the film, and the process passability was good.

  X: Process passability was poor due to adhesion of particles or resin white powder to metal and rubber rolls, shrinkage of film, tearing, generation of wrinkles, and the like.

(22) Anti-condensation property The wallpaper was affixed to a wood board with a width of 30 cm, a length of 30 cm, and a thickness of 2 cm, with a 1: 2 mixture of JIS-A6922 compatible wallpaper-based starch adhesive and water. This was left for 1 day under conditions of 40 ° C. and 90% RH, and then the condensation state on the surface of the wood board opposite to the wallpaper surface was observed to determine the anti-condensation property.

  ○: No condensation was observed on the surface of the wood board opposite to the wallpaper surface.

  X: Condensation was observed on either the wallpaper surface or the opposite surface of the wood board.

(23) Designability When actually used as a wallpaper in a house, it has a high-class feeling due to its calm luster, and the pattern irregularities are clearly visible, and it is resistant to ultraviolet light from indoor fluorescent lights and sunlight from outside. A product having a small color change, easily wiping off dirt, having excellent durability, and industrially practically used was evaluated as having a high designability, and was evaluated as “Good”. In addition, those that were inferior to any of the previous period and could not be industrially put into practical use were evaluated as having low design properties, and were evaluated as x.

(24) Content of fine particles 10 g of resin or film is added to xylene heated to 135 ° C., and the polypropylene resin is dissolved in xylene. Particles that are insoluble in xylene are precipitated by centrifugation, and are collected by filtration, and the particle content is calculated by measuring the weight.

(25) Average particle diameter Particles before addition to resin or 10 g of film is added to xylene heated to 135 ° C., and polypropylene resin is dissolved in xylene. The particles that are insoluble in xylene are precipitated by centrifugation and collected by filtration, and photographed at 30,000 magnifications using a transmission electron microscope (H-7100FA, manufactured by Hitachi, Ltd.). The equivalent circle diameter is measured for each particle on the photograph. The equivalent circle diameter was determined for 100 particles, and the particle diameter was 0 to 0.05 μm, 0.05 to 0.10 μm, 0.10 to 0.15 μm, 0.55 to 0.60 μm, And determine how many particles are contained in each group. An intermediate value of each group and a representative diameter _{d i} of the group is (e.g., _d i = 0.125 .mu.m in a group of 0.10～0.15Myuemu), the particle number _{n i} in the group, the average by the following formula The particle diameter (weight average diameter) is calculated.

(26) Fabric weight of nonwoven fabric Cut the nonwoven fabric into a 10cm square, dry it in a hot air oven at 100 ° C for 24 hours, place it in a desiccator containing dried silica gel, cool it to 23 ° C, and then weigh its weight with a direct balance measured determined, it was calculated in terms of weight per 1 m ^2.

  The present invention will be described with reference to the following examples, but the present invention is not limited thereto.

( Reference Example 1)
As a wallpaper of the present invention, as a resin composition of a polypropylene film laminated on a substrate, a polypropylene having a melting temperature of 167 ° C. (manufactured by Sumitomo Chemical Co., Ltd., FLX80E4, MFR: 7 g / 10 min, II: 96.5%, 96.6% by weight (hereinafter abbreviated as PP) and high melt tension polypropylene resin (manufactured by Basell, HMS-PP type: PF-814, MFR: 3 g / 10 min, hereinafter abbreviated as HMS-PP) 3% by weight N, N′-dicyclohexyl-2,6-naphthalenedicarboxyamide (manufactured by Shin Nippon Rika Co., Ltd., “NJESTER” NU-100, hereinafter abbreviated as NU-100). 2% by weight, organic particles crosslinked PMMA particles (average particle size 2 μm, manufactured by Nippon Shokubai Chemical Industry Co., Ltd., type: “Eposter” MA1002) 0.2 After adding and mixing the amount%, supplying to a twin screw extruder, melt mixing at 300 ° C, extruding into a gut shape, passing through a 20 ° C water bath, cooling and cutting to 3 mm length with a chip cutter, then 100 ° C And dried for 2 hours. The β crystal ratio of the β crystal nucleating agent-added PP (hereinafter abbreviated as β crystal PP) was 55%. Next, the β-crystal PP is supplied to an extruder heated to 300 ° C. and melted, extruded into a sheet shape through a T die die, and brought into close contact with a cast drum heated to a surface temperature of 122 ° C. An unstretched film was produced. Next, the unstretched film is introduced into an oven heated and held at 100 ° C., and after preheating, in the longitudinal direction (longitudinal direction, that is, the traveling direction of the film, hereinafter abbreviated as MD direction), a stretching speed of 100,000% / It was stretched 5 times in minutes and cooled with a roll at 130 ° C. Subsequently, the film stretched in the MD direction is guided to a tenter while holding both ends of the film with clips, and stretched in a direction perpendicular to the MD direction (lateral direction, hereinafter abbreviated as TD direction) in an atmosphere heated to 140 ° C. After stretching 8 times at 2000% / min (area ratio: longitudinal stretch ratio x lateral stretch ratio = 40 times), in order to complete the crystal orientation of the polypropylene film and to give flatness and dimensional stability, Then, a relaxation heat treatment of 5% in the lateral direction was performed at 155 ° C., and after uniform cooling, the solution was cooled to room temperature. Further, on the surface of the film, one surface was subjected to corona discharge treatment in the air in order to be bonded to the base material, and the surface was wound at a wet tension of 37 mN / m.

  By magnifying and observing the cross section of the polypropylene film obtained as described above with an SEM at 8000 times, it was confirmed that the thickness was 25 μm and the film contained many fine and non-nucleated voids.

Next, a polyester nonwoven fabric (hereinafter abbreviated as PET nonwoven fabric) having a thickness of 0.2 mm and a basis weight of 200 g / m ² was used as the substrate. As a method of laminating the nonwoven fabric and a polypropylene film, "CRISVON" TA-170 as an adhesive onto a PET nonwoven (Dainippon Ink and Chemicals, Incorporated) 100 parts by weight, crosslinking agent "Kurisubo down" ACCEL T (Dainippon Ink (Chemical Industry Co., Ltd.) 5 parts by weight and 30 parts by weight of toluene were mixed and coated with a gravure roll having grooves at 5 mm intervals so that the thickness after drying was 5 μm. Then, after drying for 1 minute at a drying temperature of 130 ° C., after passing through a pair of nip rolls (metal roll and rubber roll) kept at 120 ° C. superimposed on the above polypropylene film, pressure-bonded at a linear pressure of 9 kg / cm and laminated After drying at 120 ° C. for 1 minute, heat treatment was performed at 140 ° C. for 30 seconds to obtain a wallpaper. The properties of the polypropylene film thus obtained are shown in Table 1, and the properties of the wallpaper are shown in Table 2 . ( Reference Example 2)
In Reference Example 1, instead of “HMS-PP”, the same procedure as in Reference Example 1 was performed except that 1 wt% of high melt tension polypropylene (“Daploy” 130D, MFR = 2 g / 10 min) manufactured by Borealis was added and mixed. I got a polypropylene film and wallpaper. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2 .

(Example 3)
As the core layer resin composition of the polypropylene film of the present invention, 94.6% by weight of polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., WF836DG3, MFR: 7 g / 10 min, II: 96.5%), “HMS-PP” 2% by weight of type PF-814 and a polyolefin elastomer resin, ultra-low density polyethylene by metallocene catalyst method (manufactured by Dow Chemical Co., Ltd., “Engage” 8411; MFR: 18 g / 10 min (190 ° C.); 3% by weight, sometimes simply abbreviated as V-LDPE), and N, N′-dicyclohexyl-2,6-naphthalenedicarboxamide (manufactured by Shin Nippon Rika Co., Ltd., “NU— 100 ") 0.2% by weight, crosslinked PMMA particles of organic particles as a slip agent (average particle size 2 µm, manufactured by Nippon Shokubai Chemical Industry Co., Ltd., type:" D 0.2% by weight of Star “MA1002) was added and mixed, supplied to a twin screw extruder, melted and mixed at 300 ° C., extruded into a gut shape, cooled through a 20 ° C. water bath, cooled by a chip cutter and 3 mm long. And then dried at 100 ° C. for 2 hours. In addition, as the skin layer resin composition, homopolypropylene F107BV (MFR: 7 g / 10 min, II: 98%; hereinafter may be simply abbreviated as hPP2) manufactured by Mitsui Chemicals, Inc. Zinc oxide 30% master chip having a diameter of 0.5 μm (made by Showa Denko K.K., sometimes simply abbreviated as ZnO) 33% by weight, and as a β crystal nucleating agent, N, N′-dicyclohexyl-2,6- 0.05% by weight of naphthalene dicarboxyamide (manufactured by Shin Nippon Rika Co., Ltd., “NU-100”) was added and fed to a heated twin screw extruder. After melting and kneading at 300 ° C., it was extruded into a gut shape, cooled by passing through a 20 ° C. water bath, cut to a length of 5 mm with a chip cutter, and then dried at 100 ° C. for 2 hours. The whole core layer resin is supplied to a heated extruder (a), melted and kneaded at 230 ° C., filtered through a 35 μm cut leaf disk filter, and then a multi-manifold type two-layer / three-layer composite. Introduced into the base. Next, the entire resin of the skin layer was supplied to a heated extruder (b), melted and kneaded at 230 ° C., filtered through a 35 μm cut wire mesh filter, and then introduced into the die. In the die, the molten polymer of the extruder (b) is laminated on both sides of the molten polymer of the extruder (a) and coextruded into a sheet shape, and is closely adhered onto a cast drum heated to a surface temperature of 125 ° C. The skin layer surface on the non-drum surface side was cooled and solidified by blowing air at 100 ° C. through an air knife to prepare an unstretched sheet. The unstretched sheet was guided to a roll heated and held at 100 ° C., preheated, stretched 6 times in the longitudinal direction of the sheet at a stretching speed of 200,000 / min, and cooled with a roll at 50 ° C. Subsequently, the both ends of the stretched sheet are guided to a tenter while being gripped by clips, and stretched 10 times at a stretching speed of 2,500% / min in the width direction of the sheet in an atmosphere heated at 135 ° C. (Area magnification: longitudinal stretching) In order to complete the crystal orientation of the sheet and impart flatness and dimensional stability, a relaxation heat treatment of 5% in the transverse direction at 155 ° C. is performed in the tenter to uniformly and gradually. After cooling, a polypropylene film and wallpaper were obtained in the same manner as in Reference Example 1 except that a polypropylene film was obtained by cooling to room temperature. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2. The wallpaper polypropylene film of the present invention has high whiteness, cushioning rate and embossing rate, excellent air permeability and moisture permeability, low color change rate, excellent cleavage resistance, and wallpaper laminated with the polypropylene film is embossed. It can be seen that the rate is high, the air permeability and moisture permeability are excellent, and the anti-condensation property is excellent.

Example 4
In Example 3, a reactive hot melt adhesive (Dainippon Ink & Chemicals, “Tie Hose” H-104) was applied as an adhesive on the polypropylene film of Example 3 at 110 ° C. for 5 μm, A wallpaper was obtained in the same manner as in Reference Example 1 except that it was laminated at 70 ° C. with a cardboard having a specific gravity of 1.0 and a thickness of 300 μm. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2. The polypropylene film of the wallpaper of the present invention has high whiteness, cushion rate, and embossing rate, excellent air permeability and moisture permeability, low color change rate, and wallpaper laminated with the polypropylene film has high embossing rate and air permeability. It turns out that it is excellent in moisture permeability and dew condensation prevention.

(Example 5)
In Example 3, a wallpaper was obtained in the same manner as in Reference Example 1 except that the thickness of the polypropylene film was 40 μm and the thickness of the PET nonwoven fabric was 0.2 mm. Thus the characteristics of the obtained polypropylene film in Table 1, showing characteristics of the wallpaper in Table 2. The polypropylene film of the wallpaper of the present invention has high whiteness, cushion rate, and embossing rate, excellent air permeability and moisture permeability, low color change rate, and wallpaper laminated with the polypropylene film has high embossing rate and air permeability. It turns out that it is excellent in moisture permeability and dew condensation prevention.

(Example 6)
In Example 3, as the core layer resin composition of the polypropylene film of the present invention, polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., FLX80E4, MFR: 6 g / 10 min, II: 96.5%) 96.6% by weight, As a polyolefin-based elastomer resin, low-density polyethylene by a metallocene catalyst method (manufactured by Sumitomo Chemical Co., Ltd., “Excellen FX” CX5016; MFR: 17 g / 10 min (190 ° C.); hereinafter may be simply abbreviated as mVLDPE) 3% by weight, β crystal nucleating agent, N, N′-dicyclohexyl-2,6-naphthalenedicarboxamide (manufactured by Shin Nippon Rika Co., Ltd., “NU-100”) 0.2% by weight, as slip agent Cross-linked PMMA particles of organic particles (average particle size 2 μm, manufactured by Nippon Shokubai Chemical Industry Co., Ltd., type: “Eposter” MA1002) 0 2% by weight added and mixed, supplied to an extruder heated to 200 ° C, melted, extruded into a sheet through a dissimilar three-layer T-die die, and adhered onto a cast drum heated to a surface temperature of 120 ° C And solidified by cooling to prepare an unstretched sheet. The unstretched sheet was guided to a roll heated and held at 120 ° C., preheated, stretched 4 times in the longitudinal direction of the sheet at a stretching speed of 80,000% / min, and cooled with a roll at 50 ° C. Subsequently, the both ends of the stretched sheet are guided to a tenter while being gripped by clips, and stretched 6 times in the width direction of the sheet at a stretching speed of 1,500% / min in an atmosphere heated to 140 ° C. (Area magnification: longitudinal stretching) In order to complete the crystal orientation of the sheet and impart flatness and dimensional stability, a relaxation heat treatment of 5% in the transverse direction is performed at 155 ° C. in the tenter and uniformly and gradually. After cooling, a wallpaper was obtained in the same manner as in Reference Example 1 except that a polypropylene film was obtained by cooling to room temperature. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2. The wallpaper polypropylene film of the present invention has high whiteness, cushioning rate and embossing rate, excellent air permeability and moisture permeability, low color change rate, excellent cleavage resistance, and wallpaper laminated with the polypropylene film is embossed. It can be seen that the rate is high, the air permeability and moisture permeability are excellent, and the anti-condensation property is excellent.

( Reference Example 7)
As a resin composition of the polypropylene film of the present invention, polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., type: FS2016, MFR: 2.1 g / 10 min, II: 96%), 40% by weight, and β crystal nucleating agent, SUNOCO "BEPOL" (Type: B022-SP, MI: 1.8 g / 10 min) 60% by weight is mixed, supplied to an extruder heated to 200 ° C, melted, and sheet-shaped through the inside of the T die die Then, the sheet was extruded onto a cast drum heated to a surface temperature of 110 ° C. and cooled and solidified to produce an unstretched sheet. The unstretched sheet was guided to 130 rolls, preheated, stretched 4 times in the longitudinal direction of the sheet, and cooled with a roll at 50 ° C. Subsequently, the both ends of the stretched sheet are guided to a tenter while being gripped by clips, and after stretching 6 times in the width direction of the sheet in an atmosphere heated to 140 ° C. (area ratio: longitudinal stretch ratio × lateral stretch ratio = 24), In order to complete the crystal orientation of the sheet and to provide flatness and dimensional stability, a relaxation heat treatment of 5% in the transverse direction is performed at 155 ° C. in a tenter, and after uniform cooling, it is cooled to room temperature and then a polypropylene film Got. As a base material, 80% by weight of a polyethylene terephthalate resin (hereinafter abbreviated as PET) and 20% by weight of a resin obtained by copolymerizing 10 mol% of dimer acid with polybutylene terephthalate (hereinafter abbreviated as PBT-D) were added and mixed. It was melt-extruded at 0 ° C., closely contacted on a cast drum maintained at a surface temperature of 25 ° C., and cooled and solidified to produce an unstretched film having a thickness of 200 μm. This unstretched film is passed between a metal first roll electrodeposited with synthetic diamond particles having a particle size of 200 to 500 μm and a metal second roll nip roll, and then guided to a heating roll at 70 ° C. To obtain a PET film having through holes with an average pore diameter of 2 μm. Then, PET "CRISVON" TA-170 as the adhesive (produced by Dainippon Ink & Chemicals, Inc.) on the film 100 parts by weight having a through-hole, the cross-linking agent "Kurisubo down" ACCEL T (Dainippon Ink & Chemicals ( Co., Ltd.) 2 parts by weight and 30 parts by weight of toluene were mixed and coated with a gravure roll having grooves at 5 mm intervals so that the thickness after drying was 3 μm. Then, after drying for 1 minute at a drying temperature of 130 ° C., the laminate was passed through a pair of nip rolls (metal roll and rubber roll) kept at 100 ° C. superimposed on the above polypropylene film, and pressure-bonded at a linear pressure of 7 kg / cm and laminated After drying at 100 ° C. for 1 minute, heat treatment was performed at 120 ° C. for 30 seconds to obtain a wallpaper. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2 .

( Reference Example 8)
As a resin composition of the polypropylene film laminated on the base material of the wallpaper of the present invention, a polypropylene having a melting temperature of 167 ° C. (manufactured by Sumitomo Chemical Co., Ltd., FLX80E4, MFR: 7 g / 10 min, II: 96.5%, below) 96.6% by weight (abbreviated as PP) and N, N′-dicyclohexyl-2,6-naphthalenedicarboxamide (manufactured by Shin Nippon Rika Co., Ltd., “NJester” NU-100, (Hereinafter abbreviated as NU-100) 0.3% by weight is mixed, supplied to a twin-screw extruder, melted and mixed at 300 ° C, extruded into a gut shape, cooled through a 20 ° C water bath and cooled by a chip cutter. After cutting to 3 mm length, it was dried at 100 ° C. for 2 hours. The β crystal ratio of the β crystal nucleating agent-added PP (hereinafter abbreviated as β crystal PP) was 85%. Next, the β-crystal PP 88.7% by weight, Dainippon Ink Chemical Co., Ltd. titanium oxide fine particle 60% by weight master chip (type “PEONY WHITE L-11165MPT) 8.3% by weight, V-LDPE “Engage” 8411 of 3% by weight was mixed, supplied to an extruder heated to 220 ° C., melted, extruded into a sheet through a T die die, and heated on a cast drum heated to a surface temperature of 120 ° C. Next, the unstretched film was introduced into an oven heated and held at 100 ° C., and after preheating, the longitudinal direction (longitudinal direction, that is, the traveling direction of the film, hereinafter abbreviated as MD direction). To 4) at a stretching speed of 8,000% / min and cooled with a roll at 127 ° C. Subsequently, both ends of the film stretched in the MD direction are held by clips. In the atmosphere heated to 140 ° C. while being heated to 140 ° C., the film was stretched 7 times at a stretching speed of 2,000% / min in the direction perpendicular to the MD direction (lateral direction, hereinafter abbreviated as TD direction) (area magnification: (Longitudinal stretch ratio × transverse stretch ratio = 28 times), and then, in order to complete the crystal orientation of the polypropylene film and to impart flatness and dimensional stability, a relaxation heat treatment of 5% in the transverse direction is performed at 155 ° C. in the tenter. The film was gradually cooled to room temperature, and then the surface of the film was subjected to corona discharge treatment in air in order to be bonded to the base material, and the film was wound with a surface wetting tension of 37 mN / m. .

  By magnifying and observing the cross section of the polypropylene film thus obtained by SEM at 8,000 times, it was confirmed that the thickness was 25 μm and contained many fine and non-nucleated voids inside the film. .

Next, a polyester nonwoven fabric (hereinafter abbreviated as PET nonwoven fabric) having a thickness of 0.2 mm and a basis weight of 150 g / m ² was used as a substrate. As a method of laminating the nonwoven fabric and a polypropylene film, "CRISVON" TA-170 as an adhesive onto a PET nonwoven (Dainippon Ink and Chemicals, Incorporated) 100 parts by weight, crosslinking agent "Kurisubo down" ACCEL T (Dainippon Ink (Chemical Industry Co., Ltd.) 5 parts by weight and 30 parts by weight of toluene were mixed and coated with a gravure roll having grooves at 5 mm intervals so that the thickness after drying was 5 μm. Then, after drying for 1 minute at a drying temperature of 130 ° C., the laminate was passed through a pair of nip rolls (metal roll and rubber roll) kept at 100 ° C. superimposed on the above polypropylene film, and pressure-bonded at a pressure of 7 kg / cm after lamination. After drying at 100 ° C. for 1 minute, heat treatment was performed at 120 ° C. for 30 seconds to obtain a wallpaper. The properties of the polypropylene film thus obtained are shown in Table 1, and the properties of the wallpaper are shown in Table 2 .

(Comparative Example 1)
In Reference Example 1, a low-density polyethylene resin having a melting temperature of 110 ° C. (“Sumikasen” L705, manufactured by Sumitomo Chemical Co., Ltd., hereinafter abbreviated as LDPE) and 30% by weight of polyethylene wax (“High Wax “110P, Mitsui Chemicals, Inc., hereinafter abbreviated as PE-WAX” 20% by weight, calcium carbonate (trade name: “Star Piggot” 15A, Shiraishi Calcium Co., Ltd., average particle size 0.15 μm, Reference Example 1 except that a composition containing 50% by weight (hereinafter abbreviated as CaCO ₃ ) was fed to a twin screw extruder, melted and mixed at 230 ° C., and then a polyethylene film having a thickness of 20 μm was obtained by an inflation method. I got the wallpaper in the same way. Table 1 shows the characteristics of the polyethylene film and Table 2 shows the characteristics of the wallpaper. Although this polyethylene film is excellent in air permeability and moisture permeability, the whiteness is low, the cushion rate and the embossing rate are low, the color change rate is high, the cleaving resistance is inferior, and the embossing rate of the wallpaper in which the polyethylene film is laminated. Is low, and thus has a low design property.

(Comparative Example 2)
In Reference Example 7, a film was obtained by casting at a high speed of 50 m / min during extrusion casting, and the film was annealed at 120 ° C. for 5 minutes and then stretched twice in the longitudinal direction at 100 ° C. to obtain a polypropylene film. Except for this, wallpaper was obtained in the same manner as in Reference Example 1. Table 1 shows the characteristics of the polypropylene film and Table 2 shows the characteristics of the wallpaper. This polypropylene film has a low porosity, and is inferior in whiteness, cushioning rate, embossing rate, air permeability and moisture permeability, and a wallpaper using this film is inferior in embossing rate, air permeability and moisture permeability.

(Comparative Example 3)
Reference Example 1 in place of PP, ethylene - propylene random copolymer (Sumitomo Chemical Co., Ltd., type = FM401G, MFR = 6g / 10 min, hereinafter abbreviated as EPC) except for using the Reference Example A polypropylene film and wallpaper were obtained as in 1. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2. This polypropylene film has low porosity and inferior whiteness, cushioning rate, embossing rate, air permeability and moisture permeability. Wallpaper using this film is inferior in embossing rate, air permeability and moisture permeability, and prevents condensation. It was inferior.

(Comparative Example 4)
In Reference Example 1, a polypropylene film and wallpaper were obtained in the same manner as in Reference Example 1 except that the vertical and horizontal stretching temperatures of the polypropylene film were each increased by 20 ° C. Table 1 shows the characteristics of the polypropylene film and Table 2 shows the characteristics of the wallpaper. This polypropylene film has low porosity and inferior whiteness, cushioning rate, embossing rate, air permeability and moisture permeability. Wallpaper using this film is inferior in embossing rate, air permeability and moisture permeability, and prevents condensation. It was inferior.

(Comparative Example 5)
In Reference Example 1, instead of the polypropylene film, 25 μm-thick polybutylene terephthalate obtained by an inflation method was passed between a roll on which synthetic diamond fine particles were electrodeposited and a metal roll in the same manner as the base material in Reference Example 7. A wallpaper was obtained in the same manner as in Reference Example 1 except that a film having 2 × 10 4 holes / cm ² of holes having an average opening diameter of 3 μm was used. Table 1 shows the film characteristics and Table 2 shows the wallpaper characteristics. This film has a low porosity, a low whiteness, a cushion rate, and an embossing rate, and a wallpaper using this film has a low embossing rate and is inferior in workability and in design.

(Comparative Example 6)
As the resin composition of the polypropylene film, polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., WF836DG3, MFR: 7 g / 10 min, II: 96.5%) is 92.8% by weight, and β, nucleating agent is N, N ′ -0.2% by weight of dicyclohexyl-2,6-naphthalenedicarboxyamide (manufactured by Shin Nippon Rika Co., Ltd., “NU-100”) and calcium carbonate having an average particle diameter of 1.0 μm (manufactured by Shiraishi Calcium Co., Ltd.) ) 7% by weight was mixed and supplied to a twin screw extruder, melted and mixed at 300 ° C., extruded into a gut shape, cooled through a 20 ° C. water tank, cut into a 3 mm length with a chip cutter, and then 100 Dry at 2 ° C. for 2 hours. Next, the chip is supplied to an extruder heated to 230 ° C., melted, extruded into a sheet through a T die die, and brought into close contact with a cast drum heated to a surface temperature of 80 ° C. to be cooled and solidified. Then, an unstretched sheet was produced. The unstretched sheet was guided to a roll heated and maintained at 130 ° C., preheated, stretched 5 times in the longitudinal direction of the sheet, and cooled with a roll at 50 ° C. Subsequently, the both ends of the stretched sheet are guided to a tenter while being gripped by clips, and then stretched 9 times in the width direction of the sheet in an atmosphere heated to 145 ° C. (Area magnification: Longitudinal stretch ratio × Horizontal stretch ratio = 45 times) In order to complete the crystal orientation of the sheet and to impart flatness and dimensional stability, a relaxation heat treatment of 5% in the transverse direction at 160 ° C. is performed in the tenter, and after uniform cooling, cooling to room temperature is performed. A wallpaper was obtained in the same manner as in Reference Example 1 except that a film was obtained. The characteristics of the polypropylene film thus obtained are shown in Table 1, and the characteristics of wallpaper are shown in Table 2. The polypropylene film of this wallpaper has a high cushion rate and embossing rate and is excellent in air permeability and moisture permeability, but the whiteness is less than 60% and the color change rate is high. The design was inferior.

(Comparative Example 7)
Comparative Example 6 was the same as Comparative Example 6 except that the β crystal nucleating agent was not added to the polypropylene film resin, and 20% by weight of rutile titanium oxide having an average particle size of 0.2 μm was added instead of calcium carbonate. A polypropylene film and wallpaper were obtained. Table 1 shows the characteristics of the polypropylene film and Table 2 shows the characteristics of the wallpaper. Although this polypropylene film has high whiteness, the porosity is low, the cushion rate and the embossing rate are low, and the wallpaper using this film is inferior in the embossing rate.

  The wallpaper obtained by laminating a polypropylene film having high whiteness, cushioning rate, embossing rate, air permeability, and moisture permeability on the base material of the present invention has high embossing rate, excellent moisture permeability and air permeability, and excellent dew condensation prevention property. Therefore, generation of mold can be suppressed when used as a wallpaper of a recent highly airtight house. Moreover, since it has substantially no void nucleus such as inorganic or organic particles, a human-friendly wallpaper can be provided.

Claims (5)

A wallpaper in which a polypropylene film is laminated on a base material, wherein the polypropylene film has at least two layers of a core layer and a skin layer, and the porosity of the skin layer is lower than the porosity of the core layer, and the whiteness of polypropylene fill arm 60% or more, wallpaper cushion factor is 15% or more, embossing rate is equal to or less than 10%. The wallpaper according to claim 1, wherein the moisture permeability is in a range of 100 to 100,000 g / (m ² · d). The porosity of the polypropylene film is 20% or more, substantially has no void nucleus, the total light transmittance is in the range of 10 to 40%, the Gurley permeability is in the range of 10 to 5000 sec / 100 ml, and the ultraviolet ray The wallpaper according to claim 1, wherein the color change rate after exposure is 5% or less. The polypropylene film has a porosity of 40% or more, β-crystal activity, a polypropylene resin having a β-crystal ratio of 25% or more, and fine particles having an average particle size in the range of 0.06 to 0.4 μm, The wallpaper of Claim 1 or 2 whose content of the said microparticles | fine-particles is 3 to 20 weight% on the basis of a polypropylene resin. The wallpaper according to any one of claims 1 to 4 , wherein the substrate is selected from at least one of a nonwoven fabric, paper, and a plastic film having a through hole.