JP2019218660A - Method for producing modified cloth - Google Patents

Abstract

To provide a modified cloth that can retain a texture (bending resistance) while efficiently modifying a cloth.SOLUTION: A method for producing a modified cloth in which a cloth containing a polymer A with a melting point and/or glass transition temperature of 50°C or more and 400°C or less is modified, the polymer A being selected from an olefinic polymer, polyester polymer and polyimide polymer, has a step 1 in which a radical containing an atom (α) of an element selected from a group 15 element and a group 16 element and an atom (β) of a group 17 element in one molecule, at a ratio of the number of atoms (α): the number of atoms (β)=1:1-4:1, is irradiated with light.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a modified fabric.

In recent years, fabrics such as nonwoven fabrics and woven fabrics have been used in various fields.
As the cloth, cloth made of polyolefin or the like having excellent chemical stability or the like is used, but cloth made of polyolefin or the like has poor affinity (eg, hydrophilicity) with a component having polarity. Therefore, various affinity treatments are performed.

  As the affinity treatment, modification of a resin with an unsaturated carboxylic acid such as maleic anhydride or an acid anhydride thereof (eg, Patent Document 1), surface treatment such as corona discharge treatment, plasma treatment, and the like are known.

JP 2003-247157 A

The fabric, particularly the fabric used as a sanitary material, may be required to have a texture, specifically, a softness.
Cloth using a resin modified with maleic anhydride or the like can be made hydrophilic, but the fabric is found to have reduced rigidity, which seems to be due to the fact that the cloth becomes harder due to the interaction of the modified portion. Was. That is, when the resin was modified with maleic anhydride or the like, it was found that there was a trade-off between the rigidity and the hydrophilicity.

  In addition, when the resin is modified or surface-treated, the molecular weight of the polymer constituting the fabric decreases, or a crosslinking reaction occurs, and the polymer tends to easily deteriorate or yellow, and It has been found that there is a limit to the amount of functional groups introduced by these methods.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a modified fabric that can maintain the texture (hardness / softness) while efficiently modifying the fabric.

  As a result of research conducted by the present inventors, they have found that the above-described problems can be solved according to the following configuration examples. A configuration example of the present invention is as follows.

[1] In one molecule, the atom (α) of the element selected from the group 15 element and the group 16 element and the atom (β) of the group 17 element are obtained by dividing the number of atoms (α) by the number of atoms (β) = Step 1 of irradiating with light in the presence of a radical containing at a ratio of 1: 1 to 4: 1.
Method for producing a modified fabric obtained by modifying a fabric containing polymer A having a melting point and / or a glass transition temperature of not less than 50 ° C and not more than 400 ° C, selected from olefin-based polymers, polyester-based polymers and polyimide-based polymers. .

[2] The method for producing a modified fabric according to [1], wherein the step 1 is a step of irradiating the radicals with light in the presence of the radicals and the fabric.
[3] The method for producing a modified cloth according to [1] or [2], wherein the step 1 is a step of irradiating the radical and the cloth with light in the presence of the radical and the cloth. .

  [4] The method for producing a modified fabric according to any one of [1] to [3], wherein the fabric is a nonwoven fabric.

  [5] The method for producing a modified fabric according to any one of [1] to [4], wherein the radical is a chlorine dioxide radical.

  [6] The method for producing a modified fabric according to any one of [1] to [5], wherein the olefin-based polymer is a propylene-based polymer.

  [7] The method for producing a modified fabric according to any one of [1] to [6], wherein the fabric is a sanitary material.

According to the production method of the present invention, it is possible to provide a modified fabric capable of efficiently fabricating the fabric, specifically, maintaining the texture (rigidity) while mainly modifying the surface.
Further, according to the production method of the present invention, a decrease in the molecular weight of the polymer, a crosslinking reaction, deterioration, yellowing, a decrease in the strength of the cloth, and the like can be suppressed, and the cloth before modification had The effect by denaturation can be imparted while utilizing the features.

FIG. 1 is a schematic diagram showing a state in which a nonwoven fabric is modified in an example. FIG. 2 is a schematic diagram illustrating a method for evaluating hydrophilicity of a nonwoven fabric in Examples.

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

≪Method of manufacturing modified fabric≫
The method for producing the modified fabric according to the present invention (hereinafter, also referred to as “the present method”) includes a method in which a melting point and / or a glass transition temperature selected from an olefin-based polymer, a polyester-based polymer, and a polyimide-based polymer are 50 ° C. A method for producing a modified cloth obtained by modifying a cloth containing the polymer A having a temperature of 400 ° C. or less,
In one molecule, the atom (α) of the element selected from the group 15 element and the group 16 element and the atom (β) of the group 17 element are defined as the number of atoms (α): the number of atoms (β) = 1: 1. Step 1 of irradiating light in the presence of radicals contained in a ratio of 4: 1.

According to the present method, it is possible to easily obtain a modified fabric that can efficiently maintain the fabric (specifically, modify the surface while maintaining the texture (rigidity)). For example, a sanitary material such as a disposable diaper may require wettability or the like only at a portion that comes into contact with the skin or the like. According to this method, since it is possible to modify (modify) mainly near the surface of the polymer A (cloth) or only at a specific location, it can be said that a portion requiring modification can be efficiently modified. By doing so, it is possible to enhance the modifying effect while suppressing a decrease in the strength of the fabric before modification.
The rigidity is a measure of hardness that can be determined based on whether one end of a fabric having a predetermined length is lifted or not.

  According to the present method, the polymer A is efficiently modified (eg, oxidation treatment) by a very simple method of merely irradiating the radical with light, and under extremely mild conditions such as normal temperature and normal pressure. can do. Further, according to the present method, for example, the polymer A can be efficiently modified (oxidation reaction) without using a radical generator such as a peroxide or an azo compound which may be unstable at a handling temperature. .

<Step 1>
In the step 1, in one molecule, the atom (α) of an element selected from the group 15 element and the group 16 element and the atom (β) of the group 17 element are added to the number of atoms (α): This is a step of irradiating light in the presence of a radical containing the number = 1: 1 to 4: 1.
The step 1 may be performed in the presence of the radical, but is preferably a step of irradiating the radical with light in the presence of the radical, more preferably the radical in the presence of the radical and the polymer A. This is a step of irradiating the light. The polymer A used at this time may be a fabric containing the polymer A, or may be a thread-like polymer or the like as a raw material of the fabric, but is a fabric containing the polymer A. Is preferred.

The radical includes an atom (α) of an element selected from a Group 15 element and a Group 16 element and an atom (β) of a Group 17 element.
The radical may include two or more atoms of a Group 15 element, may include two or more atoms of a Group 16 element, and may include one or more atoms of a Group 15 element and a Group 16 element, respectively. And may contain two or more atoms of Group 17 elements. However, in these cases, the ratio of the number of atoms is the ratio of the total number of atoms of the group 15 element and the group 16 element to the total number of atoms of the group 17 element.

The atom (α) preferably includes nitrogen, oxygen, and sulfur, and is particularly preferably oxygen.
The atom (β) preferably includes chlorine, bromine and iodine, and chlorine and bromine are preferable. Among these, chlorine is more preferable because a radical containing chlorine is easily available. When a radical containing chlorine is used, the light to be irradiated is preferably light containing ultraviolet light. When a radical containing bromine or iodine is used, light having a longer wavelength than the ultraviolet light can be used. Therefore, bromine and iodine are preferable depending on circumstances, for example, when the degree of freedom in selecting light is taken into consideration, or when there is a possibility that the polymer A may be deteriorated by light.

  In the radical, the ratio of the number of atoms (α) to one atom (β) in one molecule of the radical is 1 to 4, preferably 1 or 2, and more preferably 2. .

As the radical, a chlorine dioxide radical is preferable.
When light irradiation is performed in the presence of chlorine dioxide radicals (ClO _2. ), For example, it is considered that chlorine radicals (Cl.) And oxygen molecules (O ₂ ) are generated by irradiating the chlorine dioxide radicals with light.

The light (wavelength) used for the light irradiation may be appropriately selected depending on the radical used. Specifically, a wide range from the infrared region to the ultraviolet region can be selected, but is, for example, 200 nm or more, for example, 800 nm or less.
The light irradiation time is not particularly limited, but is, for example, 1 minute or more, for example, 1000 hours or less.

  Although the light source in the light irradiation is not particularly limited, for example, natural light such as sunlight is used from the viewpoint of simplicity. Further, for example, a light source such as a xenon lamp, a halogen lamp, a fluorescent lamp, and a mercury lamp may be appropriately used instead of or in addition to the natural light. Further, if necessary, a filter for cutting a wavelength other than the required wavelength may be appropriately used.

The temperature, pressure, and atmosphere for performing the step 1 are not particularly limited, but the reaction temperature is, for example, 0 ° C. or more, for example, 100 ° C. or less, and the pressure is, for example, 0.1 MPa or more, and 100 MPa or less. The atmosphere includes, for example, an air atmosphere and an inert gas atmosphere.
This method is performed, for example, in the air at normal temperature (eg, 5 to 35 ° C.) and normal pressure (atmospheric pressure) without performing any heating, pressurizing, depressurizing, or the like, as described in Examples below. It is also possible.

  The light irradiation is performed on radicals present in an aqueous phase, an organic phase and / or a gas phase. When importance is placed on reducing the load on the environment and the effect on the human body, it is preferable to perform the treatment on radicals present in the aqueous phase or gas phase.

  The aqueous phase is not particularly limited as long as it contains water.

The organic phase is not particularly limited as long as it contains an organic solvent.
The organic solvent is not particularly limited, and examples thereof include a hydrocarbon solvent and a halogenated solvent.
The organic solvent may be one kind or two or more kinds.

  Although it does not specifically limit as said hydrocarbon solvent, For example, n-hexane, cyclohexane, benzene, toluene, o-xylene, m-xylene, and p-xylene are mentioned.

  The halogenated solvent is not particularly restricted but includes, for example, methylene chloride, chloroform, carbon tetrachloride, carbon tetrabromide and fluorous solvents.

  The fluorous solvent is a solvent in which all or most of the hydrogen atoms of a hydrocarbon are substituted with fluorine atoms. The fluorous solvent may be, for example, a solvent in which 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more of the number of hydrogen atoms of a hydrocarbon are substituted with fluorine atoms.

As the fluorous solvent, for _{example, CF 3 - (CF 2)} n -CF 3 (n is 4~7), N - ((CF 2) n CF 3) 3 (n is 1 or 4), hexafluorobenzene , 1- (trifluoromethyl) undecafluorocyclohexane, 1- (trifluoromethyl) pentafluorobenzene, and octadecafluorodecahydronaphthalene, among which, for example, CF ₃ (CF ₂ ) ₄ CF ₃ is preferable. .

  Fluorous solvents have the advantage that side reactions can be suppressed or prevented, for example, due to the low reactivity of the solvent itself. Examples of the side reaction include an oxidation reaction of a solvent, a hydrogen abstraction reaction of a solvent by radicals, and a chlorination reaction.

The aqueous phase may include components other than the radicals and water, and the organic phase may include components other than the radicals and the organic solvent.
Examples of the other components include, but are not particularly limited to, a source of the radical, a Bronsted acid, a Lewis acid, and oxygen (O ₂ ).
Each of these may be used alone or in combination of two or more.
The other component may be dissolved in the aqueous phase and / or the organic phase, but may not be dissolved.
Note that one substance may also serve as a Lewis acid and a Bronsted acid. "Lewis acid" refers to a substance that acts as a Lewis acid for the source of the radical.

The source of the radical is not particularly limited, but when the radical is a chlorine dioxide radical, for example, chlorous acid (HClO ₂ ) or a salt thereof may be mentioned. The salt of chlorite is not particularly limited, and examples thereof include metal salts. Examples of the metal salt include an alkali metal salt, an alkaline earth metal salt, and a rare earth salt.
More specifically, the source of the chlorine dioxide radical is, for example, sodium chlorite (NaClO ₂ ), lithium chlorite (LiClO ₂ ), potassium chlorite (KClO ₂ ), magnesium chlorite (Mg (ClO ₂ ) ₂ ) and calcium chlorite (Ca (ClO ₂ ) ₂ ). Among these, sodium chlorite is preferred in terms of cost, ease of handling, and the like.

  The concentration of the radical generating source in the aqueous phase and / or the organic phase is not particularly limited, but is, for example, 0.0001 mol / L or more, for example, 1 mol / L or less.

The Lewis acid is not particularly limited, and may be, for example, an organic substance or an inorganic substance.
Examples of the organic substance include an ammonium ion and an organic acid (eg, carboxylic acid).
The inorganic substance may include one or both of a metal ion and a non-metal ion. The metal ion may include one or both of a typical metal ion and a transition metal ion.
Examples of the inorganic substance include alkaline earth metal ions (eg, Ca ²⁺ ), rare earth ions, Mg ²⁺ , Sc ³⁺ , Li ⁺ , Fe ²⁺ , Fe ³⁺ , Al ³⁺ , silicate ions, and the like. It may be at least one selected from the group consisting of borate ions.
Examples of the alkaline earth metal ion include calcium, strontium, barium and radium ions, and more specifically, Ca ²⁺ , Sr ²⁺ , Ba ²⁺ and Ra ²⁺ .
The "rare earth" is a general term for two elements, scandium and yttrium, and 15 elements (lanthanoids) from lanthanum to lutetium, for a total of 17 elements. Examples of the rare earth ion include a trivalent cation.

Further, when the Lewis acid is an ion, the Lewis acid may be a substance having a counter ion of the ion, such as trifluoromethanesulfonic acid ion (CF ₃ SO ₃ ⁻ ). , Trifluoroacetate ion (CF ₃ COO ⁻ ), acetate ion, fluoride ion, chloride ion, bromide ion, iodide ion, sulfate ion, hydrogen sulfate ion, sulfite ion, nitrate ion, nitrite ion, phosphate ion And phosphite ions.

The Lewis acid may be at least one selected from the group consisting of AlCl ₃ , AlMeCl ₂ , AlMe ₂ Cl, BF ₃ , BPh ₃ , BMe ₃ , TiCl ₄ , SiF ₄ and SiCl ₄ . Among these, “Ph” represents a phenyl group, and “Me” represents a methyl group.

  The Lewis acidity of the Lewis acid is, for example, 0.4 eV or more, but is not limited thereto. The upper limit of the Lewis acidity is not particularly limited, but is, for example, 20 eV or less. The Lewis acidity is, for example, Ohkubo, K .; Fukuzumi, S. Chem. Eur. J., 2000, 6, 4532, J. AM.CHEM. SOC. 2002, 124, 10270-10271, or J. Org. Chem. 2003, 68, 4720-4726.

The Bronsted acid is not particularly limited, but includes, for example, an inorganic acid and an organic acid, and specifically, for example, trifluoromethanesulfonic acid, trifluoroacetic acid, acetic acid, hydrofluoric acid, hydrochloric acid, and odor. Examples include hydrofluoric acid, hydroiodic acid, sulfuric acid, sulfurous acid, nitric acid, nitrous acid, phosphoric acid, and phosphorous acid.
Acid dissociation constant pK _a of the Bronsted acid is, for example, 10 or less. The lower limit of the pK _a is not particularly limited, for example, is -10 or more.

  The concentration of at least one of the Lewis acid and the Bronsted acid in the aqueous phase and / or the organic phase is not particularly limited, and can be appropriately set, but is, for example, 1 mg / L or more, for example, 1 g / L or less. It is.

For example, oxygen (O ₂ ) can be dissolved in the aqueous phase and / or the organic phase by blowing air or oxygen gas into the aqueous phase and / or the organic phase. At this time, for example, the aqueous phase and / or the organic phase may be saturated with oxygen (O ₂ ).
When the aqueous phase and / or the organic phase contains the oxygen (O ₂ ), for example, denaturation (oxidation reaction) of the fabric can be promoted.

<Radical generation step>
The method may include a radical generating step of generating the radical, specifically, a step of generating the radical from the radical generating source.

  The radical generating step is not particularly limited. For example, the radical generating step (eg, chlorous acid or a salt thereof) is dissolved in water and allowed to stand, and the radical generating step is performed by spontaneously generating the radical from the radical generating source. Can be. At this time, for example, the presence of at least one of the Lewis acid and the Bronsted acid in the water can promote the generation of the radical. Also, for example, the radicals can be generated by irradiating light to an aqueous phase in which the radical generating source is dissolved in water. The light irradiation may be the light irradiation in the above step 1, that is, the radicals may be irradiated with light while generating the radicals.

For example, the mechanism (mechanism) for generating chlorine dioxide radicals from chlorite ions is assumed, for example, as shown in Scheme 1 below. However, the following scheme 1 is an example of a presumed mechanism, and does not limit the present invention at all.
The first (upper) reaction formula of the following scheme 1 shows a disproportionation reaction of chlorite ion (ClO ₂ ⁻ ), and the presence of at least one of a Lewis acid and a Bronsted acid in the reaction system. It is thought that the equilibrium is likely to move to the right.
The second (middle) reaction formula in Scheme 1 below shows a dimerization reaction, in which hypochlorite ion (ClO ⁻ ) generated in the disproportionation reaction reacts with chlorite ion to form dioxide. Chlorine (Cl ₂ O ₂ ) is produced. This reaction is considered to proceed more easily as the amount of protons H ⁺ in the water increases, that is, as the water becomes more acidic.
The third (lower) reaction scheme in Scheme 1 below represents radical generation. In this reaction, dichlorine dioxide generated by the dimerization reaction reacts with chlorite ions to generate chlorine dioxide radicals.

  Further, when the polymer A has a carbon-hydrogen single bond, the reaction proceeds at the carbon-hydrogen single bond part, for example, the mechanism of the ethane oxidation reaction described in JP-A-2017-155017 ( It can be assumed that the reaction proceeds by the same mechanism as in (Mechanism).

<Modification of fabric>
In this method, the fabric containing the polymer A is modified. In the present invention, “modified fabric containing polymer A” refers to polymer A before performing step 1 (hereinafter also referred to as “unmodified polymer”. When the cloth is also referred to as “unmodified cloth”) and the polymer contained in the modified cloth obtained by the present method, the polymer contained in the modified cloth is compared with the unmodified polymer. It does not necessarily mean that the unmodified fabric itself is modified, but also includes, for example, modifying the thread of the polymer A that is a raw material of the unmodified fabric.

The method of the modification is not particularly limited. As the method of the modification, specifically, a method (I) of irradiating light in the presence of the radical and the polymer A [the step 1 is performed in the presence of the radical and the cloth, In the case of a step of irradiating light], the method (II) of contacting the system having been subjected to the step 1 with the polymer A may be carried out.
The polymer A used here may be a fabric containing the polymer A, or may be a polymer such as a thread material as a raw material of the fabric, but is a fabric containing the polymer A. Is preferred.

The method (I) is a method of irradiating the polymer A with light [the step 1 is a step of irradiating the radicals and the polymer A, particularly the cloth with light in the presence of the radicals and the cloth. Is preferable].
In this case, each of the radical and the polymer A may be separately irradiated with light. For example, it is preferable that the radical and the polymer A are simultaneously irradiated with light from one light source.

  The methods (I) and (II) may be, for example, a liquid phase method in which the polymer A is brought into contact with (immersed in) the aqueous phase containing the radicals and / or the organic phase. And / or a gas phase method in which the reaction is carried out without contacting the organic phase with the polymer A, or a gas phase method in which the reaction is carried out in the gas phase containing the radical and the polymer A. In the case where a thread-like material or fabric having hygroscopicity is used, or when a residual solvent or the like becomes a problem, a gas phase method is preferable depending on the situation.

  When the fabric or filament to be modified is present in an aqueous phase or an organic phase, the amount of the fabric or filament to be modified is preferably used in the aqueous phase or the organic phase. Although not limited, for example, it is 1 g / L or more, for example, 10 g / L or less.

Due to the modification, a functional group containing an atom (α) contained in the radical may be introduced into the polymer A, but a functional group containing a Group 15 or 16 group atom derived from oxygen in the air is introduced. In some cases. At this time, the atom (β) contained in the radical may be introduced into the polymer A.
According to this method, it is considered that the atom (β) is also introduced into the polymer A, so that the modified fabric may be expected to have the effect of the atom (β).

  It has been reported that when a low molecular weight hydrocarbon compound such as an alkane is modified using the above radical, introduction of a group 17 atom is suppressed. In some cases, it can be introduced into the polymer A together with the atoms. This is thought to be due to the fact that the density of carbon-hydrogen bonds in the polymer A tends to be higher than in the case of modifying a small molecule such as methane or ethane. The present inventors think that one of the causes may be that radicals may be stabilized by acting. However, the present invention is not limited by this estimation.

As the functional group containing the atom (α), when the radical contains oxygen, for example, a hydroxy group, a carboxy group, an aldehyde group, a carbonyl group, an ether bond, an ester bond, —C (＝ O) OOH, — O-O-.
When the atom (β) is introduced into the polymer A, the ratio [Cα] of the total amount of the atom (α) [Cα] and the total amount of the atom (β) [Cβ] to be introduced into the polymer A The lower limit of / [Cβ] is preferably more than zero, more preferably 0.01, further preferably 0.1, particularly preferably 0.5, and the upper limit is preferably 5000, more preferably 100. , More preferably 20.
The [Cα] and [Cβ] values are values specified by the XPS method. The measurement is carried out using a product name AXIS-Nova (manufactured by KRATOS) by an ordinary method.

According to this method, it is expected that the surface of the polymer A to be modified can be mainly modified. Therefore, when a cloth containing the polymer A or a filament as a raw material of the cloth is used as the polymer A to be modified, the surface of the filament constituting the cloth or the filament to be modified is used. Is considered to be mainly modified.
According to this, even if the polymer A molecules are cut or cross-linked at the time of modification, they remain near the surface of the polymer A, and the performance of the polymer A with respect to the performance such as the strength is reduced. Since it is considered that the influence can be minimized, it is advantageous in maintaining the strength of the fabric or the thread.
The surface is preferably a depth from the surface of a fabric containing the polymer A or a filament which is a raw material of the fabric is 1/10 or less of a thickness of the shape (in the case of a filament, a radius), and more preferably. Means a region of 1/20 or less. The depth of the denatured portion can be confirmed by, for example, the XPS method.

According to the present method, when the cloth A containing the polymer A or the filamentous material that is a raw material of the cloth is used as the polymer A to be modified, the entire surface of the polymer A can be modified. However, a part of the surface of the polymer A can be modified. When a fabric containing the polymer A is used as the polymer A to be modified, the entire surface of the fabric can be modified, or only a part of the surface can be modified.
According to the present method, since the denaturation proceeds through light, it is expected that the location irradiated with light, that is, the surface of the polymer A can be mainly denatured.
In addition, by irradiating light to only one surface of the cloth, it is possible to denature only a specific portion by controlling the light-irradiated portion with a modified cloth or a photomask, etc. It is expected that the ratio of the portion to the native portion can be freely controlled.

For example, the area of the portion to be modified may be appropriately selected depending on the desired use of the modified fabric, such as when the fabric of the present invention is used in a form such as being bonded to an injection molded article or the like. With the whole being 100%, the preferred lower limit is preferably 1%, 5%, 10%, 20%, 30%, and 50% in this order, and the preferred upper limit is 100%, and more preferably 90%. The denatured region can be specified by a known method such as the XPS method.
It is considered that the modification proceeds from a radical of a group 17 element generated by irradiating the radical with light. Therefore, it is considered that the modification occurs at a portion where the radical contacts the polymer A to be modified. For example, in the method (I), when irradiating the radical and the polymer (A) with light, it is considered that the area of the polymer A to be modified is irradiated with light and the modified area is substantially equivalent. May be possible.
In some cases, the peripheral part irradiated with light or the deep part of the pore to which light does not reach may be modified, but the ratio is small.

[Polymer A]
The polymer A is a polymer selected from an olefin polymer, a polyester polymer, and a polyimide polymer, and has a melting point and / or a glass transition temperature of 50 ° C or more and 400 ° C or less. .

The olefin polymer is not particularly limited, and examples thereof include an ethylene polymer, a propylene polymer, a butene polymer, a 4-methyl-1-pentene polymer, a cyclic olefin polymer, and ethylene and propylene. , Butene, 4-methyl-1-pentene, hexene, octene, and other olefins. Further, for example, as a raw material of the copolymer, a compound other than an olefin, for example, an aromatic vinyl compound such as styrene or (meth) acrylic acid (ester) may be used.
Among these, ethylene-based polymers, propylene-based polymers, butene-based polymers, and 4-methyl-1-pentene-based polymers are preferable, and ethylene-based polymers, propylene-based polymers, and 4-methyl-1-pentene-based polymers are preferred. Polymers are more preferred, and propylene polymers are particularly preferred.

  The polyester polymer is not particularly limited, and examples thereof include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polylactic acid, and copolymers thereof.

  The polyimide-based polymer is not particularly limited, and examples thereof include polymers described in JP-A-2013-256732, JP-A-2011-132611, and JP-A-2009-228190.

  The polymer A includes other polymers, various stabilizers such as an antioxidant, a heat stabilizer, a light stabilizer, a weather stabilizer, an antistatic agent, a hydrophilic agent, a repellent agent, as long as the object of the present invention is not impaired. It may contain additives such as a liquid agent, a nucleating agent, a slip agent, an antiblocking agent, an antifogging agent, a lubricant, a dye, a pigment, a natural oil, a synthetic oil, an antibacterial agent, and a flame retardant.

  The polymer A may be a polymer having a melting point and / or a glass transition temperature of 50 to 400 ° C. The above melting point and glass transition temperature are measured by the following method or a method equivalent thereto using the following differential scanning calorimeter (DSC device). Note that another differential scanning calorimeter may be used as long as it is confirmed that the same result as the following apparatus is obtained.

Using a diamond DSC (3) type differential scanning calorimeter manufactured by PerkinElmer, about 5.0 mg of a sample was heated at a temperature-increasing rate of 10 ° C / min from 30 ° C in a nitrogen atmosphere at a predetermined temperature (olefin polymer). , 320 ° C., polyester-based polymer: 350 ° C., polyimide-based polymer: 420 ° C.) and kept at that temperature for 10 minutes. (However, in the case of using a polymer that decomposes when the temperature is raised to the above-mentioned predetermined temperature, the holding temperature may be appropriately adjusted to be low as usual.) Further, the temperature is lowered to 30 ° C at a rate of 10 ° C / min. Then, after maintaining at that temperature for 5 minutes, the temperature is raised to the same temperature as the predetermined temperature at a rate of 10 ° C./minute. The endothermic peak observed at the time of the second heating is defined as a melting peak, and the temperature at which the melting peak appears is determined as a melting point (Tm). When the melting peak is multimodal, the temperature at which the highest-temperature side melting peak appears is defined as the melting point.
The glass transition temperature (Tg) is sensed when the DSC curve is bent due to a change in specific heat and the base line moves in parallel when the temperature is raised for the second time. The temperature at the intersection of the tangent to the base line at a temperature lower than the bend and the tangent to the point where the inclination is maximum at the bent portion is defined as the glass transition temperature (Tg).

  The intrinsic viscosity [η] of the polymer A in decalin at 135 ° C. is preferably 0.5 to 20 dl / g, more preferably 0.8 to 18 dl / g, and particularly preferably 1 to 15 dl / g.

When the polymer is an olefin-based polymer, the melt flow rate measured according to the ASTM1238 standard varies depending on the melting point of the resin used, as described below, but the preferred range of the melt flow rate is 0. 0.1 to 600 g / 10 min. A preferred lower limit is 1 g / 10 minutes, more preferably 3 g / 10 minutes, and still more preferably 5 g / 10 minutes. On the other hand, a preferred upper limit is 500 g / 10 minutes, more preferably 400 g / 10 minutes.
Preferred measurement conditions for the melt flow rate (ASTM1238 standard) are as follows.
190 ° C., 2.16 kg load for ethylene polymer, 230 ° C., 2.16 kg load for propylene polymer, 260 ° C., 5 kg load for 4-methyl-1-pentene polymer In the case of a cyclic olefin polymer, the temperature is 260 ° C. and the load is 2.16 kg.

[Polymer A in thread state]
Examples of the polymer A in the thread state include a fibrous polymer A. Such a fibrous polymer A can be produced by a conventionally known method, and specifically, is obtained by spinning from a pellet-shaped polymer A or the like. In the spinning, the polymer and the additive may be used to produce a fiber containing the additive.

[Fabric containing polymer A]
Examples of the fabric containing the polymer A include a fabric obtained by weaving, depositing, knitting, and the like of the polymer A in a thread state. The fabric in the present invention includes woven fabric (woven fabric), nonwoven fabric, and knitted fabric, and also includes products such as disposable diapers and sanitary products. Among these, a nonwoven fabric is preferred from the viewpoint that the effects of the present invention are more exhibited.

  As the nonwoven fabric, a conventionally known nonwoven fabric can be used without any particular limitation. Examples of the configuration and manufacturing method of the nonwoven fabric include the configurations and manufacturing methods described in International Publication WO 2004/065680 and JP-A-2002-302862.

[Modified cloth]
The modified fabric obtained by the present method tends to be able to maintain the properties of the polymer A before modification, particularly fabric and fibers. For example, when a nonwoven fabric is used, functions such as hydrophilicity can be imparted while maintaining the required soft touch.
On the other hand, a modified nonwoven fabric using a conventional modification technique such as maleic anhydride tends to be hard and poor in flexibility. This can be inferred to be due to the interaction of the denatured portion.

  The modified fabric obtained by the present method may be used as it is, or the functional group introduced as described above may be further reacted with other components to enhance the function or change the property. Is also good. For example, it is possible to use the above-mentioned functional group as a scaffold to bind to a higher hydrophilic group or a hydrophilic material.

The modified fabric is preferably applicable to various uses, and is particularly suitably used for sanitary materials. For example, in addition to disposable diapers (for example, for infants and silver generations), products such as sanitary products, wound treatment drug sheets and drug tapes (for example, Band Aid (registered trademark)), and the like can be given. Since these products are in direct contact with the skin and wounds, they need not only hygiene but also texture (softness) and peelability.
The modified fabric is, in addition to the sanitary materials, conventional woven fabrics, nonwoven fabrics, applications in which knits have been used, for example, filters, separators, packaging materials, clothing, soundproofing materials, thickeners, various membranes It can be used for many applications such as supports.

  Hereinafter, examples of the present invention will be described. However, the present invention is not limited to the following examples.

[Example 1]
10 g of sodium chlorite (manufactured by Sigma-Aldrich) and 100 mL of ultrapure water are put in a polycontainer, and sodium chlorite is dissolved in the ultrapure water, and then a 35 to 37% aqueous hydrochloric acid solution (Fujifilm Wako Pure Chemical Co., Ltd.) 1 ml) was added to prepare a mixed solution. The presence of chlorine dioxide radicals in the mixture under these conditions was separately confirmed by the ESR method. This mixed solution was placed in a shallow vat having a size of about 22 cm × 16 cm × 1.5 cm and placed on a net shelf. Next, a polypropylene nonwoven fabric (Syntex PK-108, manufactured by Mitsui Chemicals, Inc., melting point: about 160 ° C.) having a size of about 32 cm × 21 cm was placed on the bat so as not to touch the mixed solution. Further, a glass bat having a size of about 33 cm × 24 cm × 3 cm in height was placed on the polypropylene non-woven fabric as shown in FIG. Light having a wavelength of 365 nm was irradiated from the upper part of the glass vat with Hololight Kaku DC12V manufactured by Py Photonics KK for 30 minutes at 50 to 70 mW / cm ² . Thereafter, the mixed solution was prepared again, and replaced with the mixed solution inside the shallow vat after light irradiation. Further, light was irradiated in the same manner as described above, except that the surface of the non-woven fabric placed on the bat was reversed. Thereafter, the nonwoven fabric was dried under reduced pressure to obtain a modified nonwoven fabric.
The obtained modified nonwoven fabric had the same degree of rigidity and softness as the untreated nonwoven fabric (Syntex PK-108).

<Evaluation of hydrophilicity of nonwoven fabric>
The untreated nonwoven fabric (Syntex PK-108) and the modified nonwoven fabric were each fixed on a 45 ° inclined plate. Then, about 1 mL of tap water was dropped with a pipette from about 50 mm above each nonwoven fabric surface, and it was confirmed whether each nonwoven fabric absorbed water. Table 1 shows the results.

  As described above, the modified nonwoven fabric obtained by the present method has a good balance between hydrophilicity and rigidity, which can be considered as an alternative index of texture. The modified nonwoven fabric is considered to be suitable for sanitary materials such as diapers, sanitary products, and cut protection products, as well as filters, clothes, packaging materials, and membrane supports. In particular, it is highly likely to be suitable for sanitary materials.

Claims (7)

In one molecule, the atom (α) of the element selected from the group 15 element and the group 16 element and the atom (β) of the group 17 element are defined as the number of atoms (α): the number of atoms (β) = 1: 1. Step 1 of irradiating light in the presence of radicals having a ratio of ４4: 1.
Method for producing a modified fabric obtained by modifying a fabric containing polymer A having a melting point and / or a glass transition temperature of not less than 50 ° C and not more than 400 ° C, selected from olefin-based polymers, polyester-based polymers and polyimide-based polymers. .   The method for producing a modified cloth according to claim 1, wherein the step 1 is a step of irradiating the radical with light in the presence of the radical and the cloth.   The method for producing a modified cloth according to claim 1 or 2, wherein the step 1 is a step of irradiating the radicals and the cloth with light in the presence of the radicals and the cloth.   The method for producing a modified fabric according to any one of claims 1 to 3, wherein the fabric is a nonwoven fabric.   The method for producing a modified fabric according to any one of claims 1 to 4, wherein the radical is a chlorine dioxide radical.   The method for producing a modified fabric according to any one of claims 1 to 5, wherein the olefin-based polymer is a propylene-based polymer.   The method for producing a modified fabric according to any one of claims 1 to 6, wherein the fabric is a sanitary material.

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