JP2023108466A - Antiviral urethane resin sheet - Google Patents

Abstract

To provide an antiviral urethane resin sheet having high antiviral properties, excellent in scratch resistance, abrasion resistance and designability.SOLUTION: An antiviral urethane resin sheet comprises a skin layer containing a urethane resin and an antivirus layer disposed on one face of the skin layer. The antivirus layer contains an alkoxysilane-based quaternary ammonium salt, a solvent-based urethane resin binder, and an additive made of silicone resin, and a delustering agent.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an antiviral urethane resin sheet.

In recent years, due to the increasing awareness of environmental hygiene, it is used in automobile interior parts, railway vehicle and aircraft interior parts, furniture, shoes, footwear, bags, interior and exterior materials for construction, clothing covering materials and linings, wall covering materials, etc. It is desired to impart antiviral properties to the synthetic leather used, which has excellent durability.
As a urethane resin sheet, for example, application to synthetic leather such as a synthetic resin skin material is being studied. Synthetic leather has, on its outermost surface, an embossed pattern similar to that of natural leather, that is, a grain pattern, and is required to have a matte appearance with fine ruggedness. For example, with regard to automotive interior products, as vehicles become more luxurious, it is becoming important to impart antiviral properties to synthetic leather, which is the surface material for interiors, without reducing the sense of luxury.

Synthetic leather manufacturing process release sheet and method for manufacturing synthetic leather, which is applied as a surface layer of synthetic leather, comprising a functional particle-containing layer, in order to manufacture synthetic leather imparted with functionality such as antibacterial properties has been proposed (see, for example, Patent Document 1).
A functional quaternary ammonium organosilane composition has also been proposed as a functional material that imparts antiviral properties (see, for example, Patent Document 2).

Japanese Unexamined Patent Application Publication No. 2021-30683 Japanese Patent Publication No. 2013-501742

However, in the technique described in Patent Document 1, since the functional particles contained in the functional particle-containing layer are mainly antibacterial metal particles, the appearance of the surface is limited to those having gloss. There is a problem that when stress is applied to the metal particles, the metal particles may fall off. In Patent Document 1, for example, there is no focus on abrasion resistance, wear resistance, etc. when used for vehicle interior materials.
The antibacterial particles described in Patent Document 2 are antibacterial granules containing carrier particles agglomerated by a binder containing a quaternary ammonium organosilane composition, and when used as the outermost layer of synthetic leather or the like, the antibacterial granules have excellent abrasion resistance. However, there is a problem that the durability, abrasion resistance, etc. are not sufficient.

An object of an embodiment of the present invention is to provide an antiviral urethane resin sheet that has good antiviral properties and is excellent in abrasion resistance, abrasion resistance, and design.

Means for solving the problems include the following embodiments.
<1> A skin layer containing a urethane resin, and an antiviral layer provided on one side of the skin layer, the antiviral layer comprising an alkoxysilane-based quaternary ammonium salt and a solvent-based urethane resin. An antiviral urethane resin sheet containing a binder, an additive comprising a silicone resin, and a matting agent.

<2> The antiviral urethane resin sheet according to <1>, which is synthetic leather.
<3> The antiviral layer according to <1> or <2>, wherein the antiviral layer contains 17 parts by mass to 26 parts by mass of the alkoxysilane-based quaternary ammonium salt with respect to 100 parts by mass of the total solid content of the antiviral layer. Antiviral urethane resin sheet.

<4> Any one of <1> to <3>, wherein the antiviral layer contains 4 parts by mass to 6 parts by mass of the silicone resin additive per 100 parts by mass of the total solid content of the antiviral layer. The antiviral urethane resin sheet according to 1.
<5> Any one of <1> to <4>, wherein the antiviral layer contains 11 parts by mass to 14 parts by mass of the matting agent with respect to 100 parts by mass of the total solid content of the antiviral layer. antiviral urethane resin sheet.

<6> The antiviral urethane resin sheet according to any one of <1> to <5>, wherein the antiviral layer has a thickness of 6.5 μm to 10.5 μm.
<7> The antiviral urethane resin sheet according to any one of <1> to <6>, wherein the antiviral layer further contains an acrylic resin binder.

<8> Any one of <1> to <7>, wherein the matting agent contains at least one type of particles having an average particle size of 2 μm to 12 μm selected from the group consisting of inorganic fillers and organic fillers The described antiviral urethane resin sheet.

<9> The antiviral urethane resin sheet according to any one of <1> to <8>, in which whitening is not visually confirmed after a scratch resistance test is performed under the following conditions.
-Scratch resistance test-
An antiviral urethane resin sheet with a diameter of 120 mm, which is the subject, is adhesively fixed on the turntable of a Taber scratch tester (manufactured by TABER INDUSTRISE), and the cutting edge of a tungsten carbide cutter is brought into contact with the surface of the subject. One rotation is performed at a load of 1.96 N and a rotational speed of 0.5 revolutions/minute (hereinafter referred to as rpm).
<10> According to JIS Z 8741 (1997), any of <1> to <9> having a surface gloss value of less than 1.4 as measured by Method 3 "60° Specular Glossiness Measurement Method" 1. The antiviral urethane resin sheet according to 1.

According to an embodiment of the present invention, it is possible to provide an antiviral urethane resin sheet that has good antiviral properties and is excellent in abrasion resistance and abrasion resistance.

1 is a schematic cross-sectional view showing one embodiment of an antiviral urethane resin sheet of the present disclosure; FIG. FIG. 11 is a schematic cross-sectional view showing the layer structure of the antiviral urethane resin sheet of Example 11;

The antiviral urethane resin sheet of the present disclosure will be described in detail below.
The description of the constituent elements described below may be made based on representative embodiments of the present disclosure, but the present disclosure is not limited to such embodiments.
In addition, in the present disclosure, "to" indicating a numerical range is used to include the numerical values described before and after it as a lower limit and an upper limit.
In the present disclosure, in the numerical ranges described in stages, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of another numerical range described in stages. . Also, in the numerical ranges described in the present disclosure, the upper or lower limits of the numerical ranges may be replaced with the values shown in the examples.
In the present disclosure, combinations of preferred aspects are more preferred aspects.
In the present disclosure, when there are multiple substances corresponding to each component in the composition, the amount of each component in the composition is the total amount of the multiple substances present in the composition unless otherwise specified. means.
In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved.

"Total solid content" in the present disclosure refers to, for example, the amount of components excluding solvent among all components contained in the composition.
A “layer containing a resin” in the present disclosure refers to a “layer formed containing a resin that is the main component of the layer”. That is, the "layer containing a resin" in the present disclosure is a resin layer containing only a resin, and a resin composition that further contains optional components such as a plasticizer, a colorant, and an ultraviolet absorber in addition to the resin that is the main component. It is used in the sense of including both formed layers.
In the present disclosure, the term "resin as a main component" refers to a resin containing 60% by mass or more of the total amount of the resin composition containing the component.

<Antiviral urethane resin sheet>
The antiviral urethane resin sheet of the present disclosure includes a skin layer containing a urethane resin and an antiviral layer provided on one surface of the skin layer, the antiviral layer being an alkoxysilane-based quaternary It contains an ammonium salt, a solvent-based urethane resin binder, an additive comprising a silicone resin, and a matting agent.

The antiviral urethane resin sheet of the present disclosure (hereinafter sometimes referred to as "resin sheet of the present disclosure") will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing one aspect of the layer structure of the antiviral urethane resin sheet 10 of the present disclosure.
The antiviral urethane resin sheet 10 shown in FIG. 1 includes a skin layer 12 containing urethane resin and an antiviral layer 14 provided on one surface of the skin layer 12 . The antiviral urethane resin sheet 10 shown in FIG. 1 is preferably used so that the antiviral layer 14 exhibiting antiviral properties becomes the outermost surface during use.

The antiviral urethane resin sheet of the present disclosure may be used as it is as a resin sheet, or may be applied to synthetic leather.
There is no particular limitation on the mode of applying the resin sheet of the present disclosure to synthetic leather. For example, the resin sheet of the present disclosure may be bonded to one surface of a base fabric via an adhesive layer to form a synthetic leather, and the surface of a resin laminate having known layers such as a base material layer, a foam layer, and a base fabric may be applied as a skin layer.
When laminating the resin sheet of the present disclosure with a base fabric or other resin layer, a squeezing roll having unevenness on the surface is used, and the squeezing roll is in contact with the antiviral layer side of the resin sheet of the present disclosure for lamination embossing. By processing, an uneven pattern can be formed on the surface of the antiviral layer opposite to the skin layer side.
By applying the resin sheet of the present disclosure to the surface of synthetic leather, antiviral properties can be imparted to the surface of synthetic leather.

Hereinafter, the resin sheet of the present disclosure will be sequentially described together with the materials constituting the sheet and the manufacturing method thereof.

(1. Epidermal layer)
The skin layer in the resin sheet of the present disclosure contains urethane resin.
-Urethane resin-
The urethane resin contained in the skin layer is not particularly limited as long as it can be molded into a sheet. Urethane resins include polycarbonate-based polyurethanes, polyether-based polyurethanes, polyester-based polyurethanes, modified products thereof, and the like.
Among them, polycarbonate-based polyurethane is preferable from the viewpoint of better long-term durability. Due to its good long-term durability, the resin sheet of the present disclosure can be suitably used for applications such as automobile interior materials, and can impart good antiviral properties to automobile interior materials.
As an example of preferable physical properties of the urethane resin, a 100% modulus value measured at 20° C. is 2 MPa (2×10 ⁶ N/m ² ) to 40 MPa.
Here, the 100% modulus value is a value indicating hardness measured at 20° C. according to JIS K 6253 (1997).
When the 100% modulus value is within the above range, the skin layer containing the urethane resin and, by extension, the resin sheet of the present disclosure having the skin layer easily develops preferable stretching properties.

The skin layer may contain only one type of urethane resin, or may contain two or more types. The content of the urethane resin in the skin layer can be 80 to 100 parts by mass, preferably 85 to 95 parts by mass, per 100 parts by mass of the total solid content of the skin layer.

-Other ingredients-
In addition to the urethane resin, which is the main component, the skin layer may optionally contain other components such as known additives as long as the effects of the present disclosure are not impaired.
Other ingredients that the skin layer may contain include colorants, processing aids, plasticizers, fillers, and the like. When the skin layer contains components other than the urethane resin, the content of the other components is preferably within a range that does not reduce the adhesion between the skin layer and the antiviral layer.

-Other ingredients: colorant-
The skin layer may contain a coloring agent.
When the skin layer contains a coloring agent, the coloring agent is not particularly limited, and dyes, pigments, and the like can be appropriately selected and used.
Coloring agents include inorganic pigments such as titanium white (titanium dioxide), zinc white, ultramarine blue, cobalt blue, red iron oxide, vermilion, yellow lead, titanium yellow, carbon black, quinacridone, permanent red 4R, isoindolinone, and hansa yellow. A, organic pigments or dyes such as phthalocyanine blue, indanthrene blue RS, aniline black, metal pigments selected from the group consisting of metal foil powder such as aluminum and brass, titanium dioxide-coated mica and basic lead carbonate foil powder and pearl luster (pearl) pigments selected from the group consisting of: Among them, pigments, which are colorants excellent in weather resistance and durability, are preferred.

When the skin layer contains a coloring agent, it may contain only one coloring agent, or may contain two or more coloring agents for purposes such as toning.
There is no particular limitation on the content of the coloring agent in the skin layer-forming composition used for forming the skin layer, and the type and content of the coloring agent to be used are appropriately selected according to the desired hue of the resin sheet. do it.
From the viewpoint of uniformity of the skin layer, the content of the colorant is preferably 20% by mass or less based on the total solid content of the composition for forming the skin layer.

-Thickness of skin layer-
The thickness of the skin layer is preferably in the range of 20 μm to 70 μm, more preferably in the range of 20 μm to 50 μm, from the viewpoint of better durability and design.
The thickness of the skin layer, the thickness of the later-described antiviral layer in the resin sheet of the present disclosure, and the thickness of other layers provided as desired can be measured by observing a cut surface obtained by cutting the resin sheet perpendicularly to the surface direction. can. Therefore, the film thickness of each layer in the resin sheet of the present disclosure refers to the film thickness after drying.

-Method of forming skin layer-
Formation of the skin layer can be performed by applying a known film forming method. The film-forming method includes, for example, a method in which a skin layer-forming composition containing a urethane resin is applied onto a temporary support such as release paper to form a film, and a known film-forming method for applying the skin layer-forming composition, such as , a calendar method, an extrusion method, a casting method, and the like to form a sheet.
As the coating method, known coating methods such as knife coater method, blade coater method, roll coater method, bar coater method, curtain coater method, gravure coater method and the like can be applied, and knife coater method is preferred.

(2. Antiviral layer)
The antiviral layer in the resin sheet of the present disclosure is composed of an alkoxysilane-based quaternary ammonium salt as an antiviral component, a solvent-based urethane resin binder, and an additive comprising a silicone resin to impart a matte appearance to the antiviral layer. and a matting agent.

-Alkoxysilane-based quaternary ammonium salt-
The antiviral layer in the resin sheet of the present disclosure contains an alkoxysilane-based quaternary ammonium salt as an antiviral component.
The alkoxysilane-based quaternary ammonium salt is a compound having an ammonium group having an alkyl group with antiviral properties and good adsorptivity, and an alkoxysilyl group.
Examples of anions that react with ammonium groups to form salts include chloride ions, bromide ions, fluoride ions, iodine ions, arylsulfonyl ions, and acetyl ions. Acetyl ions are preferred.
The alkoxysilyl group includes trimethoxysilyl group, triethoxysilyl group and the like.
An alkylene group having 2 to 5 carbon atoms may be linked between the alkoxysilyl group and the ammonium salt.
Specific examples of the alkoxysilane-based quaternary ammonium salt include the compounds shown below, but the alkoxysilane-based quaternary ammonium salt of the present disclosure is not limited to the following specific examples.
(CH ₃ O) ₃ Si(CH ₂ ) ₃ N ⁺ (CH ₃ ) ₂ C ₁₈ H ₃₇ Cl ⁻
(CH ₃ O) ₃ Si(CH ₂ ) ₃ N ⁺ (CH ₃ ) ₂ (C ₁₀ H ₂₁ )Cl ⁻
(CH ₃ O) ₃ Si(CH ₂ ) ₃ N ⁺ (CH ₃ ) ₂ C ₁₈ H ₃₇ Br ⁻
(CH ₃ O) ₃ Si(CH ₂ ) ₃ N ⁺ (CH ₃ ) ₂ (C ₁₀ H ₂₁ ) Br ⁻
(C ₂ H ₅ O) ₃ Si(CH ₂ ) ₃ N ⁺ (CH ₃ ) ₂ C ₁₈ H ₃₇ Cl ⁻
_{( C2H5O ) 3Si ( CH2 ) 3N} ^{+ (} _CH3 ) _2CH2C6H5Cl-

The content of the alkoxysilane-based quaternary ammonium salt in the antiviral layer is 17 parts by mass to 26 parts by mass with respect to 100 parts by mass of the total solid content of the antiviral layer, from the viewpoint that it is easy to impart sufficient antiviral properties. and more preferably 18 parts by mass to 22 parts by mass.

-Solvent urethane resin binder-
The antiviral layer contains a solvent-based urethane resin as a binder from the viewpoint of achieving uniform layer formation.
Solvent-based urethane resins include at least one solvent-based polyurethane selected from the group consisting of organic solvent-soluble polycarbonate-based polyurethanes, polyether-based polyurethanes, polyester-based polyurethanes, and modified products thereof. The solvent-based polyurethane may be a one-component system or a two-component system.
Polycarbonate-based polyurethanes, silicone-modified polycarbonate-based polyurethanes, and the like are preferable, and polycarbonate-based polyurethanes are more preferable, from the viewpoint of durability, hydrolysis resistance, heat deterioration resistance, and the like.
The antiviral layer may contain only one type of solvent-based urethane resin, or may contain two or more types.
A solvent-based urethane resin refers to a urethane resin that can be dissolved in an organic solvent, methyl ethyl ketone, in an atmosphere of 25° C. in an amount of 10% by mass or more.

The antiviral layer may contain a thermoplastic resin (hereinafter referred to as another resin) other than the solvent-based urethane resin as a binder. Other resins that can be used for the antiviral layer include acrylic resins, and acrylic resins are preferable from the viewpoint of compatibility with the solvent-based urethane resin and transparency. Specific examples of acrylic resins as binders include polymers or copolymers of methacrylic acid or methacrylic acid esters represented by polymethyl methacrylate (PMMA), copolymers of alkyl methacrylate, alkyl acrylate and styrene. A polymer etc. are mentioned.
When the antiviral layer contains an acrylic resin as another resin, it may contain only one type of acrylic resin, or may contain two or more types.
When the antiviral layer contains other resins, the content of the acrylic resin is preferably 15 parts by mass or less with respect to 100 parts by mass of the total amount of the resin as the binder.

The content of the resin binder in the antiviral layer is preferably 54 parts by mass to 68 parts by mass with respect to 100 parts by mass of the solid content of the antiviral layer.

-Additive made of silicone resin-
The antiviral layer contains at least one additive made of silicone resin (hereinafter sometimes referred to as a specific additive).
When the antiviral layer contains the specific additive, the antiviral layer has good abrasion resistance and abrasion resistance.
As the silicone resin, it is possible to appropriately select and use from the group consisting of known silicone resins and modified silicone resins. The silicone resin may be a resin having a siloxane structural unit, and may be a homopolymer composed of a siloxane structural unit, or a copolymer of a siloxane structural unit and a structural unit derived from acrylic acid.
Urethane-modified silicone resins, ester-modified silicone resins, and the like can be used as modified silicone resins.

The antiviral layer may contain only one type of specific additive, or may contain two or more types.
The content of the specific additive in the antiviral layer is 4 parts by mass to 6 parts by mass with respect to 100 parts by mass of the solid content of the antiviral layer from the viewpoint of further improving scratch resistance. It is preferably 5 parts by mass to 6 parts by mass.

- Matting agent -
The antiviral layer contains matting agents. Since the antiviral layer contains the matting agent, the resin sheet of the present disclosure is excellent in design. Here, the term "designability" means that the resin sheet has a matte appearance with suppressed surface gloss.
The matting agent preferably contains at least one type of particles having an average particle size of 2 μm to 12 μm selected from the group consisting of inorganic fillers and organic fillers.
The particle size of the matting agent is preferably particles with an average particle size of 2 μm to 12 μm, more preferably particles with an average particle size of 4 μm to 10 μm, from the viewpoint of better matting effect.
The average particle size of the matting agent particles is measured at a disk rotation speed of 3000 rpm by a light transmission centrifugal sedimentation method using water as a dispersion medium using an automatic particle size analyzer (model number: CAPA-300) manufactured by Horiba. The value measured by the method of measuring the standard median diameter is used.
Inorganic fillers as matting agents include silica particles and glass beads. Examples of organic fillers include resin particles, resin beads, and the like, and more specific examples of organic fillers include urethane beads, acrylic beads, collagen particles, and the like.
The matting agent may be transparent particles or colored particles.

The antiviral layer may contain only one type of matting agent, or may contain two or more types depending on the purpose.
The content of the matting agent in the antiviral layer is preferably 11 parts by mass to 14 parts by mass with respect to 100 parts by mass of the solid content of the antiviral layer from the viewpoint of further improving the design. It is more preferably 12 parts by mass to 13 parts by mass.

-Other ingredients-
The antiviral layer may contain other ingredients depending on the purpose, in addition to the above essential ingredients. Other components include antiviral agents other than alkoxysilane-based quaternary ammonium salts, antibacterial agents or disinfectants, colorants, and the like.

-Thickness of antiviral layer-
The thickness of the antiviral layer is preferably 6.5 μm to 10.5 μm, more preferably 7 μm to 9 μm, from the viewpoint of better antiviral properties, abrasion resistance, abrasion resistance, and design.
The thickness of the antiviral layer can be measured in the same manner as the thickness of the epidermal layer described above.

- Method for forming an antiviral layer -
In the resin sheet of the present disclosure, as a method for forming the antiviral layer, a composition for forming an antiviral layer containing the above antiviral agent, resin binder, specific additive, matting agent, and optionally other ingredients A method of applying a substance to one side of the skin layer described above and drying the same can be mentioned. As the coating method, any known coating method may be applied. Known coating methods include a knife coater method, a blade coater method, a roll coat method, a bar coater method, a curtain coater method, a gravure coater method, and the like. A direct gravure coater method, which is one aspect of the coater method, and a reverse gravure coater method are preferred.
The amount of the composition for forming an antiviral layer applied by the coating method is 7 g/m ² as the amount applied during drying from the viewpoint of better antiviral properties, scratch resistance, abrasion resistance, and design. It is preferably between 11 g/m ² and more preferably between 7.5 g/m ² and 9.5 g/m ² .

(3. Preferred physical properties of the resin sheet of the present disclosure)
3-1. Abrasion Resistance The resin sheet of the present disclosure may be used as it is as a resin sheet, synthetic leather, or the like, or may be used as a surface material for existing synthetic leather. From the viewpoint of maintaining antiviral properties for a long period of time, the resin sheet of the present disclosure preferably has good durability.
As a measure of durability, it is preferable to have abrasion resistance in which whitening is not visually confirmed after conducting an abrasion resistance test under the following conditions.
The test is performed at normal temperature (20°C). Here, the term "whitening" means that the contact surface of the test piece with the cutting edge of the cutter is roughened by friction and visually looks white.
-Scratch resistance test-
An antiviral urethane resin sheet with a diameter of 120 mm, which is the subject, is adhesively fixed on the turntable of a Taber scratch tester (manufactured by TABER INDUSTRISE), and the cutting edge of a tungsten carbide cutter is brought into contact with the surface of the subject. One rotation is performed at a load of 1.96 N and a rotational speed of 0.5 rpm.

3-2. Appearance The resin sheet of the present disclosure preferably has a matte appearance with reduced gloss. As for the matte appearance, the surface gloss value measured by Method 3 "60° Specular Glossiness Measurement Method" in accordance with JIS Z 8741 (1997) is preferably less than 1.4, and 1.2. The following are more preferable.
The surface gloss value measured by the 60° specular glossiness measurement method is less than 1.4, so that when the resin sheet of the present disclosure is applied to, for example, synthetic leather, the surface has a matte and heavy appearance. can be done.

Since the resin sheet of the present disclosure has the above configuration, it has good antiviral properties and excellent abrasion resistance and abrasion resistance, so it can be applied to various applications that require antiviral properties. . In addition, since the antiviral layer, which is the outermost layer, contains an appropriate amount of matting agent, the resin sheet has a matte appearance and is excellent in design.

(4. Other layers)
The resin sheet of the present disclosure may have other layers depending on the purpose of the resin sheet in addition to the skin layer and the antiviral layer.
Other layers include, for example, an adhesive layer, a base fabric, a resin foam layer, a substrate layer, a design layer, and the like.

4-1. Adhesive Layer The resin sheet of the present disclosure may have an adhesive layer.
The adhesive layer is useful for adhering the laminate of the skin layer and the antiviral layer to other layers such as a base fabric and a substrate layer. Also, the adhesive layer can be used to directly adhere the resin sheet of the present disclosure to the surface of a hard material such as a wall surface.

The adhesive layer can be formed of an adhesive resin.
The adhesive layer can be formed by applying a known adhesive to the surface of the resin sheet opposite to the antiviral layer side of the skin layer.
The adhesive used to form the adhesive layer provided on the resin sheet as desired is not particularly limited, and is appropriately selected according to the purpose. Suitable adhesives include, for example, urethane resin adhesives, polyvinyl chloride adhesives, polyvinylidene chloride adhesives, styrene resin adhesives, and the like.
The adhesive layer can be formed by a method of applying a resin as an adhesive to the surface of the epidermis layer opposite to the antiviral layer side. As the coating method, the above-described known coating method can be appropriately applied.
The thickness of the adhesive layer is preferably in the range of 5 μm to 50 μm, more preferably 10 μm to 50 μm, from the viewpoints of adhesion between adjacent layers and texture of the resin sheet.

4-2. Base fabric The resin sheet of the present disclosure may have a base fabric.
By having the base fabric, the strength of the resin sheet is improved, and it can be used as it is as a synthetic leather.
Any of woven fabrics, knitted fabrics, and non-woven fabrics can be used as the base fabric without any particular limitation as long as it has the required strength and flexibility and has a certain degree of stretchability.
Knitted fabric is preferable from the viewpoint of stretchability, and known knitted fabrics such as warp knitting, warp knitting, raschel knitting, and pile knitting can be used as appropriate.

As the fibers that make up the base fabric, synthetic fibers such as polyester fiber, polyamide fiber, polyacrylonitrile fiber, acrylic fiber, polyurethane fiber, etc., natural fibers such as cotton and hemp, regenerated fibers such as rayon fiber, etc. are used depending on the purpose. can do.
The number of fibers constituting the base fabric may be one, or two or more.
For example, by using polyurethane fibers together as fibers constituting the base fabric, the stretchability of the base fabric is further improved. Moreover, the strength of the base fabric can be improved by using Kevlar fiber, which is a high-strength fiber of polyamide, together.

The thickness of the base fabric can be appropriately selected depending on the purpose. From the viewpoint of the strength and durability of the resin sheet, the thickness is preferably 650 μm to 1200 μm, more preferably 700 μm to 1100 μm.

4-3. Foamed Resin Layer The resin sheet of the present disclosure may have a foamed resin layer. Since the resin sheet has a foamed resin layer, the flexibility and elasticity of the resin sheet are improved.
The foamed resin layer is not particularly limited as long as it is flexible and contains air bubbles.
Examples of the resin contained in the foamed resin layer include resins shown below.
Polyolefins such as polyethylene (PE), polypropylene (PP), polybutylene (PB),
Polyurethane (PUR),
polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN);
The above resin may be modified, or may be a resin having a crosslinked structure formed by a crosslinking agent or the like.
The foamed resin layer can be formed by incorporating air bubbles formed by a known method in these resins.
The foamed resin layer may contain only one type of thermoplastic resin, or may contain two or more types thereof.
When the resin sheet has a foamed resin layer, the thickness of the foamed resin layer is preferably 100 μm to 500 μm.

4-4. Base Layer The resin sheet of the present disclosure may have a base layer. By having the base material layer, the thickness of the resin sheet is increased, and the strength and feel are improved.
The base layer preferably contains a thermoplastic resin. The thermoplastic resin that can be used for the substrate layer is not particularly limited, and can be appropriately selected from known thermoplastic resins in consideration of various conditions such as affinity between adjacent layers and stretchability of the resin sheet.
Thermoplastic resins that can be used for the substrate layer include, for example, polyethylene (PE), PP resin, PVC resin, polystyrene (PS), polyvinyl acetate (PVAc), polyurethane (urethane resin), ABS resin, acrylonitrile-styrene. Copolymers (AS resins), polycarbonates (PC), acrylic resins such as polymethyl methacrylate (PMMA), and fluororesins such as polytetrafluoroethylene (PTFE) can be used.
The base material layer can be formed by a known film forming method.
The substrate layer may contain only one type of thermoplastic resin, or may contain two or more types thereof.

4-5. Design Layer The resin sheet may have a design layer.
The design layer is a layer that imparts further design properties to the resin sheet, and may be a printed layer formed by printing, a colored layer containing a coloring agent, or a layer using these in combination. good too.
The design layer can be optionally provided on the antiviral layer side or the side opposite to the antiviral layer side of the above-described epidermis layer.

The design layer can be formed, for example, by a printing method on the surface of the skin layer described above. Examples of the printing method for forming the design layer include a method of forming by a known printing method using a printing ink containing a resin. The resin-containing printing ink is at least one selected from acrylic resins, urethane resins, polyolefin resins, polyamide resins, and vinyl chloride-vinyl acetate copolymers, from the viewpoint of being able to form clear printed images. It preferably contains a resin.
When the design layer is a printed layer, there is no particular limitation on the printing method that can be applied to form the design layer, and any printing method such as gravure printing (intaglio printing), letterpress printing, offset printing, inkjet printing, and screen printing can be used. can be applied. The design layer formed by the printing method may be a discontinuous layer including areas to which the printing ink is adhered, or may be a continuous uniform layer made of the printing ink.

(5. Layer structure of resin sheet)
The resin sheet of the present disclosure includes a skin layer and an antiviral layer on one side of the skin layer, as shown in FIG. 1, and can be used for various purposes.
Alternatively, an embodiment as shown in FIG. 2, in which an adhesive layer, a skin layer and an antiviral layer are provided in this order on a base fabric bonded to a base fabric via an optional adhesive layer, may be adopted. can.
FIG. 2 is a schematic cross-sectional view showing one embodiment of an antiviral urethane resin sheet comprising a base fabric and an adhesive layer as optional layers.
The antiviral urethane resin sheet 20 shown in FIG. 2 includes a skin layer 12 and an antiviral layer 14 on one side of a base fabric 16 with an adhesive layer 18 interposed therebetween.
A resin sheet provided with a base fabric as shown in FIG. 2 can be applied as it is as a synthetic leather to automobile interior materials, building interior materials, bags, shoes, clothes, and the like.

(6. Manufacturing method of resin sheet)
The method for manufacturing the resin sheet of the present disclosure described above is not particularly limited, and a known manufacturing method can be appropriately employed.
An example of the manufacturing method is given below, but the manufacturing method is not limited to the following.

The method for producing a resin sheet of the present disclosure includes a step of forming a skin layer using a skin layer-forming composition containing at least a urethane resin (step A), and applying an alkoxy A step of forming an antiviral layer by applying an antiviral layer-forming composition containing a silane-based quaternary ammonium salt, a solvent-based urethane resin binder, a specific additive, and a matting agent (step B). including.
The method for producing a resin sheet includes, for example, a step of forming an adhesive layer on the surface of the epidermal layer opposite to the antiviral layer side (step C), and the adhesive layer obtained in step C is placed on the opposite side of the epidermal layer side. An optional step such as a step of adhering the base fabric to the side surface (step D) can be further included.

(Process A)
In step A, a skin layer containing urethane resin is formed. Forming methods include, for example, a method in which a skin layer-forming composition containing a urethane resin is applied onto a temporary support such as release paper and then dried to form a skin layer, and a skin layer-forming composition containing a urethane resin. Examples include a method of forming an object into a sheet by applying a known film-forming method.
The wet coating amount when applying the coating method is determined according to the thickness of the skin layer to be formed, and can be, for example, 120 g/m ² to 200 g/m ² .
Step A may include a step of applying a skin layer-forming composition containing a urethane resin onto a temporary support such as release paper, and then drying the formed skin layer-forming composition layer.
Drying can be performed using a hot air dryer, a warm air dryer, or the like. The drying temperature can be 80°C to 120°C, preferably 90°C to 100°C. The drying time can be 1 to 3 minutes under the above temperature conditions.
As described above, the thickness of the skin layer to be formed is preferably 5 μm to 200 μm, more preferably 30 μm to 150 μm, in terms of film thickness after drying.
After drying, it is preferably aged at a temperature of 40° C. to 50° C. for 24 to 48 hours, and then peeled off from a temporary support such as release paper to obtain a skin layer.

(Step B)
In step B, the prepared antiviral layer-forming composition is applied onto one surface of the epidermal layer obtained in step A to obtain an antiviral layer-forming composition layer. Application may be performed by a known method, for example, a knife coater method or the like can be applied.
The wet coating amount when applying the coating method is determined according to the thickness of the antiviral layer to be formed, and can be, for example, 20 g/m ² to 50 g/m ² .
Drying can be performed using a hot air dryer, a warm air dryer, or the like. The drying temperature can be from 80°C to 100°C, preferably from 80°C to 90°C. The drying time can be 40 seconds to 2 minutes under the above temperature conditions.
As described above, the thickness of the skin layer to be formed is preferably 5 μm to 200 μm, more preferably 30 μm to 150 μm, in terms of film thickness after drying.

Hereinafter, the resin sheet of the present disclosure will be specifically described with reference to Examples, but the present disclosure is not limited to the following specific examples, and various modifications are possible.

(Manufacture of antiviral urethane resin sheet)
[Example 1]
Components 1 to 5 were mixed according to the following formulation to prepare a composition for forming a skin layer.
The solid content of the skin layer-forming composition was about 13% by mass.
- Composition for Forming Skin Layer -
1. 1-liquid type solvent-based polycarbonate-based urethane resin (solvent-based urethane resin: resin solid content 20% by mass) 100 parts by mass2. Solvent (dimethylformamide: DMF) 20 parts by mass3. Solvent (propylene glycol monomethyl ether: PGM) 15 parts by mass4. Solvent (isopropyl alcohol: IPA) 5 parts by mass5. Colorant (carbon black) 15 parts by mass

The skin layer-forming composition thus obtained was applied onto the surface of the prepared release paper using a knife coater in such an amount that the wet coating amount was 150 g/m ² . formed a layer.
The formed skin layer-forming composition layer was dried at 100° C. for 2 minutes using a hot air dryer to form a skin layer on the release paper. The film thickness of the formed skin layer after drying was 20 μm.
The dried skin layer was further aged at a temperature of 50° C. for 48 hours, and then the release paper was peeled off. (Step A)

According to the following formulation, components 6 to 10 were mixed to prepare an antiviral layer-forming composition.
The solid content of the antiviral layer-forming composition was about 30% by mass.
-Antiviral layer-forming composition-
6. Antiviral agent solution 20 parts by mass 7. One-component polycarbonate-based urethane resin (solvent-based urethane resin: resin solid content 18% by mass) 100 parts by mass 8. Solvent (MEK) 10 parts by mass9. Specific additive (urethane-modified silicone resin) 5 parts by mass10. Matting agent (silica particles: average particle size 7 μm) 12 parts by mass

A methanol solution of trimethoxysilylpropyldimethyloctadecyl ammonium chloride was used as the alkoxysilane-based quaternary ammonium salt, which is an antiviral agent.
The content of the methoxysilane-based quaternary ammonium salt was 20.6 parts by mass with respect to 100 parts by mass of the solid content of the obtained composition for forming an antiviral layer.

The obtained composition for forming an antiviral layer was applied to one surface of the skin layer obtained in step A using a gravure coater in an amount such that the wet coating amount was 30 g/m ² . An antiviral layer-forming composition layer was formed on the surface.
Then, it was heated at 90° C. for 1 minute using a hot air dryer to form an antiviral layer with a thickness of 9 μm on the surface of the skin layer, thereby obtaining a resin sheet of Example 1.

[Example 2]
In the composition for forming an antiviral layer used in Example 1, component 6. A resin sheet of Example 2 was obtained in the same manner as in Example 1, except that the amount of the antiviral agent solution was changed from 20 parts by mass to 30 parts by mass.
The content of the methoxysilane-based quaternary ammonium salt was 25.7 parts by mass with respect to 100 parts by mass of the solid content of the obtained composition for forming an antiviral layer.

[Example 3]
In the composition for forming an antiviral layer used in Example 1, component 6. A resin sheet of Example 3 was obtained in the same manner as in Example 1, except that the amount of the antiviral agent solution was changed from 20 parts by mass to 15 parts by mass.
The content of the methoxysilane-based quaternary ammonium salt was 17.8 parts by mass with respect to 100 parts by mass of the solid content of the obtained composition for forming an antiviral layer.

[Example 4]
In the composition for forming an antiviral layer used in Example 1, component 9. A resin sheet of Example 4 was obtained in the same manner as in Example 1, except that the amount of the specific additive was changed from 5 parts by mass to 6 parts by mass.

[Example 5]
In the composition for forming an antiviral layer used in Example 1, component 9. A resin sheet of Example 5 was obtained in the same manner as in Example 1, except that the amount of the specific additive was changed from 5 parts by mass to 4 parts by mass.

[Example 6]
In the composition for forming an antiviral layer used in Example 1, component 10. A resin sheet of Example 6 was obtained in the same manner as in Example 1, except that the amount of the matting agent was changed from 12 parts by mass to 14 parts by mass.

[Example 7]
In the composition for forming an antiviral layer used in Example 1, component 10. A resin sheet of Example 7 was obtained in the same manner as in Example 1, except that the amount of the matting agent was changed from 12 parts by mass to 11 parts by mass.

[Example 8]
A resin sheet of Example 8 was obtained in the same manner as in Example 1, except that the wet coating amount of the composition for forming an antiviral layer was changed from 30 g/m ² to 36 g/m ² .

[Example 9]
A resin sheet of Example 9 was obtained in the same manner as in Example 1, except that the wet coating amount of the composition for forming an antiviral layer was changed from 30 g/m ² to 23 g/m ² .

[Example 10]
Example 1 was repeated except that an antiviral layer-forming composition obtained by adding 2 parts by mass of a fluorine-modified acrylic resin as a binder to the antiviral layer-forming composition used in Example 1 was used. A resin sheet of Example 10 was obtained in the same manner.

[Example 11]
In the same manner as in Example 1, a skin layer-forming composition layer was formed on the surface of the release paper and dried.
After that, the following steps C and D were performed to form a laminate of the skin layer, the adhesive layer and the base fabric on the surface of the release paper.
(Process C)
Components 11 to 13 below were mixed to obtain a composition for forming an adhesive layer. The solid content concentration in the adhesive layer-forming composition was 45% by mass.
-Composition for forming an adhesive layer-
11. Two-liquid type polycarbonate polyurethane resin (resin solid content 70% by mass)
100 parts by mass 12. Solvent (DMF) 50 parts by mass 13. Isocyanate-based cross-linking agent 6 parts by mass

The composition for forming an adhesive layer was applied to the surface of the skin layer formed on the release paper in such an amount that the wet coating amount was 100 g/m ² to form a layer of the composition for forming an adhesive layer. It was heated at 120° C. for 2 minutes using a hot air dryer to form an adhesive layer having a thickness of 45 μm, thereby obtaining a laminate having a release paper, a skin layer and an adhesive layer.

(Process D)
- Lamination of base fabric -
A base fabric (woven polyester fabric: thickness 1100 μm) was adhered to the adhesive layer side of the laminate obtained in step C to laminate. The heating temperature during lamination was 130°C.
The laminate of the obtained base fabric, adhesive layer and skin layer was aged in the same manner as in Example 1, and the release paper was peeled off.
An antiviral layer is formed in the same manner as in Example 1 on the surface opposite to the adhesive layer side of the skin layer from which the release paper has been peeled off, and the adhesive layer, the skin layer and the antiviral layer are formed on the base fabric. A resin sheet of Example 11 having in this order was obtained. The thickness of the obtained resin sheet was 1174 μm.

[Comparative Example 1]
In the composition for forming an antiviral layer used in Example 1, component 6. The antiviral agent contained in the antiviral agent solution was changed to an alkoxysilane-based quaternary ammonium salt, and an antiviral layer was formed using an antiviral layer-forming composition containing 30 parts by mass of monovalent copper compound nanoparticles. A resin sheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that the resin sheet was formed.
Nanoparticles mean particles with an average particle size of 1 nm to 100 nm or less.

[Comparative Example 2]
In the composition for forming an antiviral layer used in Example 1, component 7. Example 1, except that an antiviral layer-forming composition containing 100 parts by mass of polyvinyl chloride (average degree of polymerization: 1300) was used instead of the solvent-based urethane resin as the binder. A resin sheet of Comparative Example 2 was obtained in the same manner.

[Comparative Example 3]
In the composition for forming an antiviral layer used in Example 1, component 9. A resin sheet of Comparative Example 3 was obtained in the same manner as in Example 1, except that the antiviral layer was formed using an antiviral layer-forming composition containing no specific additive.

[Comparative Example 4]
In the composition for forming an antiviral layer used in Example 1, component 10. A resin sheet of Comparative Example 4 was obtained in the same manner as in Example 1, except that the antiviral layer was formed using the antiviral layer-forming composition containing no matting agent.

(Evaluation of resin sheet)
The antiviral urethane resin sheets obtained in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Tables 1 and 2 below.
In Tables 1 and 2, the antiviral agent is "methoxysilane-based quaternary ammonium salt", the one-component solvent-based polycarbonate-based urethane resin is "urethane resin A", and the two-component polycarbonate-based polyurethane resin is referred to as "urethane resin A". Each was abbreviated as "urethane resin B".

(1. Antiviral properties)
The antiviral activity value was measured on the resin sheet in accordance with ISO 21702.
Influenza virus (H3N2) was used as the virus strain.
A 50 mm square antiviral urethane resin sheet test piece was inoculated with 0.4 ml of the virus solution, and then covered with a liquid-impermeable coating film.
After inoculation of the virus solution, the test piece was allowed to stand for 24 hours in an environment with a temperature of 25±1° C. and a humidity of 90% RH or higher.
After allowing to stand for 24 hours, the coating film was peeled off, the virus was recovered from the test piece, and the virus infectivity value (antiviral activity value) was measured by the plaque method and evaluated according to the following criteria.
Rank A is evaluated as having good antiviral properties and at a level without problems.
-Evaluation criteria-
A: Antiviral activity value of 2.0 or more B: Antiviral activity value of less than 2.0

(2. Scratch resistance)
As an apparatus, a Taber scratch tester (manufactured by TABER INDUSTRISE) was used.
The resin sheets of Examples and Comparative Examples were cut to a size of 120 mm in diameter to prepare test pieces, and a hole of 15 mm diameter was made in the center of each test piece.
The obtained test piece was adhered and fixed on the turntable of a Taber scratch tester, and the cutting edge of a cutter made of tungsten carbide was brought into contact with the surface of the test piece.
Scratch resistance was evaluated by rotating the specimen and scratching it to a length of 15 mm.
The load was 1.96 N, and the turntable was rotated once at a rotation speed of 0.5 rpm.
After the test, each test piece was visually observed "front and light shielded" to evaluate the whitening state. Evaluation was performed by 10 professional monitors, and evaluation was made according to the following criteria.
-Evaluation criteria-
A: Ten monitors evaluated that no whitening was observed B: One or more of the monitors evaluated that slight whitening was observed C: One or more of the monitors evaluated that whitening was significantly observed Evaluation A is an evaluation level with no problem in practical use.
In this evaluation, even if there is one or more monitors who evaluated that "whitening is slightly observed", if there is one or more monitors who evaluated that "whitening is significantly observed", it will be evaluated as C rank. be done.

(3. Abrasion resistance)
A plane abrasion tester (manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd.) was used for the test.
Each resin sheet of Examples and Comparative Examples was cut into a width of 70 mm and a length of 300 mm to prepare a test piece.
The obtained test piece was fixed to a flat abrasion tester, and a load was applied to a friction element covered with a cotton cloth (No. 6 canvas) to wear the surface of the test piece.
With a load of 9.8 N, the friction element was reciprocated 10,000 times on the surface of the test piece at a speed of 60 reciprocations/minute.
Each test piece after the test was visually observed to evaluate the presence or absence of external damage. Evaluation was performed by 10 professional monitors, and evaluation was made according to the following criteria.
-Evaluation criteria-
A: 10 monitors evaluated that no damage to the appearance was confirmed B: One or more of the monitors evaluated that slight damage to the appearance was confirmed C: One or more of the monitors evaluated the appearance The evaluation level A, which indicates that significant damage was confirmed, is an evaluation level that poses no problem in practice.
In this evaluation, even if one or more monitors evaluated that "slight damage to the appearance was confirmed", if there were one or more monitors that evaluated that "significant damage to the appearance was confirmed" is rated as C rank.

(4. Designability)
The gloss value (60° specular gloss) of the antiviral layer surface of each resin sheet of Examples and Comparative Examples was measured according to JIS Z 8741 (1997). Micro-TRI-gloss (manufactured by BYK) was used as a measuring device.
-Evaluation criteria-
A: Gloss value is less than 1.4 B: Gloss value is 1.4 or more A is an evaluation level that poses no practical problem.

From the results in Tables 1 and 2, it can be seen that the resin sheets of Examples have good antiviral properties, excellent scratch resistance and abrasion resistance, and good design properties with suppressed gloss. .
Further, from a comparison between Example 1 and Example 10, even if the resin binder contains an acrylic resin in addition to the urethane resin, if the solvent-based urethane resin is contained as the binder, excellent effects can be obtained. I understand.
On the other hand, the resin sheets of Comparative Example 1, which contains an antiviral agent other than an alkoxysilane-based quaternary ammonium salt, and Comparative Example 2, in which the binder resin is a polyvinyl chloride resin, have a problematic level of antiviral properties. The resin sheet of Example 1 was glossy, and the design was at a practically problematic level. In addition, the resin sheet of Comparative Example 3 having an antiviral layer containing no specific additive was inferior in abrasion resistance and abrasion resistance.
The resin sheet of Comparative Example 4, which did not contain a matting agent, was inferior in abrasion resistance and abrasion resistance to each Example, and had a glossy appearance and inferior design.

10, 20 Antiviral urethane resin sheet (resin sheet)
12 Skin layer 14 Antiviral layer 16 Base fabric 18 Adhesive layer

Claims (10)

A skin layer containing a urethane resin, and
an antiviral layer provided on one side of the epidermal layer,
The antiviral layer is an antiviral urethane resin sheet containing an alkoxysilane-based quaternary ammonium salt, a solvent-based urethane resin binder, an additive comprising a silicone resin, and a matting agent. The antiviral urethane resin sheet according to claim 1, which is synthetic leather. The antiviral property according to claim 1 or 2, wherein the antiviral layer contains 17 parts by mass to 26 parts by mass of the alkoxysilane-based quaternary ammonium salt with respect to 100 parts by mass of the total solid content of the antiviral layer. Urethane resin sheet. 4. The antiviral layer according to any one of claims 1 to 3, wherein the antiviral layer contains 4 parts by mass to 6 parts by mass of the additive comprising the silicone resin with respect to 100 parts by mass of the total solid content of the antiviral layer. antiviral urethane resin sheet. The antiviral layer according to any one of claims 1 to 4, wherein the antiviral layer contains 11 parts by mass to 14 parts by mass of the matting agent with respect to 100 parts by mass of the total solid content of the antiviral layer. urethane resin sheet. The antiviral urethane resin sheet according to any one of claims 1 to 5, wherein the antiviral layer has a thickness of 6.5 µm to 10.5 µm. The antiviral urethane resin sheet according to any one of claims 1 to 6, wherein the antiviral layer further contains an acrylic resin binder. The anti-matting agent according to any one of claims 1 to 7, wherein the matting agent contains at least one kind of particles having an average particle size of 2 µm to 12 µm selected from the group consisting of inorganic fillers and organic fillers. Viral urethane resin sheet. 9. The antiviral urethane resin sheet according to any one of claims 1 to 8, wherein whitening is not visually confirmed after a scratch resistance test is performed under the following conditions.
-Scratch resistance test-
An antiviral urethane resin sheet with a diameter of 120 mm, which is the subject, is adhesively fixed on the turntable of a Taber scratch tester (manufactured by TABER INDUSTRISE), and the cutting edge of a tungsten carbide cutter is brought into contact with the surface of the subject. One rotation is performed at a load of 1.96 N and a rotational speed of 0.5 rpm. According to JIS Z 8741 (1997), the surface gloss value measured by Method 3 "60° specular glossiness measurement method" is less than 1.4. The described antiviral urethane resin sheet.