JP2021155524A - Resin film, laminate, display member, and health care sensor - Google Patents

Abstract

To provide a resin film and a laminate in which concealment is imparted without impairing elasticity and appearance quality, and to provide a display member and a health care sensor that have excellent quality.SOLUTION: Provided is a resin film that contains particular structure and urethane bond, and satisfies all of the following conditions 1 to 4. Condition 1: the resin film contains a colorant. Condition 2: the total light transmittance of the resin film measured by the method specified in JIS K 7375 (2008) is 2% or more and 20% or less. Condition 3: the storage elastic modulus of the resin film under the conditions of temperature 25°C and frequency 1 Hz is 0.5 MPa or more and 50 MPa or less. Condition 4: loss tangent of the resin film at 25°C is 0.5 or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a resin film, a laminate, a display member, and a healthcare sensor that have both elasticity, quality, and concealment.

With the development of the current IoT society, devices that are small and can be freely deformed have been developed. For example, in smartphones and tablets, displays that can be folded and rolled up have been put into practical use. In addition, for wearable sensors, devices that can bend and stretch so that they can follow the curved surface and movement of the body have been proposed, and it is expected that using these will lead to the development of new applications. Will be done.

On the other hand, when these devices are used, so-called concealment is required, in which the underlying object cannot be seen through. For example, in a display, in order to prevent the reflected light from interfering with the light emission of an internal OLED (organic light emitting diode), in a wearable sensor, in order to make the internal wiring part invisible, a resin film having a concealing property is required. Be done.

As a typical example of such a resin film resin, "ultraviolet rays capable of obtaining a cured product having excellent resin film adhesion, flexibility, and insulating properties, low transmittance, and excellent hiding power" described in Patent Document 1. A "curable resin composition" has been proposed.

Further, as an example having excellent flexibility, "a black photosensitive composition exhibiting sufficient concealing property" described in Patent Document 2 has been proposed.

Further, as an example of excellent resilience, "The black colorant has excellent patterning property capable of forming fine openings, which has been required in recent years, while having high light-shielding property, and also has excellent patterning property. A "dry resist film capable of forming a cover coat layer capable of satisfying heat-resistant pressure-bonding property, migration resistance and flexibility" has been proposed.

Japanese Unexamined Patent Publication No. 2013-194156 Japanese Unexamined Patent Publication No. 2012-141605 JP-A-2018-152606

In the resin film with concealment property used for the above-mentioned displays and sensors, it is required to impart concealment property without impairing "free bending and stretching". As "free bending and stretching", it has come to be required that it can be stretched greatly with a weak force and almost completely restored at a temperature of 0 ° C. or lower and at a fast cycle of more than once per second. That is, it has been required that the flexibility and resilience of the resin itself are not impaired even when a colorant is added to the resin composition in order to impart concealment.

Further, in displays and sensors, since this resin film is used in a laminated state by being bonded to other parts, the resin film is used so that unevenness and color difference of the resin film do not appear on the surface of the laminated body. Has come to be required to have high appearance quality. In order to obtain a high appearance quality of the resin film, it is also required to prevent the colorant from forming agglomerates and causing cissing and defects in the resin film. That is, in these applications, a resin film having concealment properties while maintaining flexibility, resilience, and appearance quality is required.

In response to the above requests, the inventors of the present invention confirmed the above-mentioned viewpoints, and found that the material proposed in Patent Document 1 is certainly excellent in concealment, but inadequate in flexibility and resilience. rice field.

Further, the material proposed in Patent Document 2 is excellent in flexibility, but has insufficient quality and resilience.

Further, the material proposed in Patent Document 3 has excellent resilience and high flexibility to some extent, but it is not at a level required for this application and its appearance quality is also insufficient.

From the above points, an object of the present invention is to provide a resin film or laminate having concealment properties, and a display member or healthcare sensor having excellent quality, without impairing elasticity and appearance quality.

In order to solve the above problems, the present inventors have completed the following inventions as a result of repeated diligent research. That is, the present invention is as follows.
(1) A resin film containing the structure of Chemical Formula 1 and a urethane bond and satisfying all of the following conditions 1 to 4.

In addition, R ^{1 of the} chemical formula 1 refers to a hydrogen or a methyl group.

Condition 1: The resin film contains a colorant.

Condition 2: The total light transmittance measured by the method specified in JIS K7375 (2008) of the resin film is 2% or more and 20% or less.

Condition 3: The storage elastic modulus of the resin film at a temperature of 25 ° C. and a frequency of 1 Hz is 0.5 MPa or more and 50 MPa or less.

Condition 4: Loss tangent of the resin film at 25 ° C is 0.5 or less.
(2) The resin film according to (1), which contains a pigment and satisfies condition 5.

Condition 5: The occupied area ratio of the pigment in the cross section of the resin film is 0.1% or more and 2.0% or less.
(3) The resin film according to (1) or (2), which contains a pigment and satisfies the following condition 6.

Condition 6: at 30% to 70% of the area in the thickness direction from the surface of the resin film, the thickness direction a ratio of 95% particle size of the pigment _{(D 95)} and 50% particle diameter _{(D 50) F A,} from the surface 0% to 30%, and, at 70% to 100% of the area, when the ratio of the average values of D95 and D50 of the pigment was _{F B,} satisfies Equations 1 and 2.

Equation 1: F _A <2.4
Equation _{2: | F A -F B |} <0.4
(4) The resin film according to any one of (1) to (3), wherein the pigment is a black pigment.
(5) The resin film according to (4), which satisfies condition 7.

Condition 7: The absorption coefficient (ε _A ) of the resin film satisfies the formula 3.

Equation 3: ε _A (1 / μm) = 100 × (Log ₁₀ 100 / T) / (A × d)> 2.0
However, A is the occupied area ratio (%) of the black pigment, d is the thickness of the resin film (μm), and T is the total light transmittance (%) of the resin film.
(6) A laminate having a supporting base material on at least one surface of the resin film according to any one of (1) to (5), and the peeling force between the supporting base material and the resin film is increased. Laminated body of 1N / 50mm or less.
(7) A display member containing the resin film according to any one of (1) to (5).
(8) A health care sensor containing the resin film according to any one of (1) to (5).

It is possible to provide a resin film or laminate with concealing properties, and a display member or healthcare sensor having excellent quality without impairing elasticity and appearance quality.

It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention. It is sectional drawing which shows an example of the laminated body in this invention.

Before describing the embodiment for carrying out the present invention, the present inventors consider the reason why the problem of the present invention cannot be solved by the prior art as follows.

First, consider the properties of the material. Colorants can be divided into pigments and dyes, mainly from the viewpoint of solubility. Dyes do not have higher weather resistance and hiding stability over time than pigments and may be limited to applications where they are not a problem. On the other hand, since the pigment does not dissolve in the coating agent, it easily forms an agglomerate, but has high weather resistance and high concealing stability over time. Therefore, when a pigment is used, it is necessary to increase the dispersibility. Further, when the pigment is dispersed in the resin precursor, it is preferable that the skeleton of the resin precursor has a functional group that interacts with the pigment over the entire area. When the functional groups that interact with the pigment are locally aggregated, the pigment is also locally aggregated, resulting in the formation of aggregates. Here, carbon black, which is a general pigment, can form two types, a π-π interaction derived from a carbon black skeleton and a hydrogen bond derived from a hydroxyl group or a carbonyl group on the surface of carbon black. Therefore, when carbon black is used as a pigment, from the viewpoint of preventing the aggregation of the pigment, the skeleton of the resin precursor has an aromatic ring or a functional group having a high hydrogen bond property and can be efficiently dispersed. Is considered preferable. On the other hand, when these functional groups are gathered, a hard segment is formed, and this cohesive force causes stability. That is, there is a trade-off relationship between the dispersibility and the restorability of the pigment, and in order to solve this, it is necessary to efficiently disperse and form a cross-linking point.

The material described in Patent Document 1 uses bisphenol A type epoxy acrylate having a number average molecular weight of 6000 or less as a resin precursor, and carbon black as a colorant. Since a resin precursor having a relatively low molecular weight is used, the degree of freedom of the resin itself is low, and accumulation of phenol sites due to π-π interaction is unlikely to occur, and therefore carbon black is unlikely to aggregate.

On the other hand, since the molecular weight of the resin precursor is low, the degree of freedom of the soft segment having no cohesive force is also low, and the flexibility is insufficient. Also, regarding stability, since the degree of freedom of the resin precursor is low, it is difficult to form an interaction between phenol sites, and since the contact frequency with acrylic groups is low, UV curing cannot be sufficiently performed. It has not reached the level required for the application.

The material described in Patent Document 2 uses both bisphenol A type epoxy acrylate and urethane acrylate having a number average molecular weight of 5000 or more and 20000 or less as a resin precursor.

Compared with that of Patent Document 1, the flexibility is high because the molecular weight is high, but the degree of freedom of the resin precursor itself is high, so that it is easy to form a microphase-separated structure between the soft segment and the hard segment, and the hard segment. Carbon black gathers due to the cohesive force between them to form an agglomerate, resulting in insufficient appearance quality. In addition, since carbon black is agglomerated, the content of carbon black required to impart high concealment is high, the specific surface area of carbon black in the resin film is high, and curing by active energy rays is high. Due to the lack of, the resilience is also insufficient.

The material described in Patent Document 3 uses a bisphenol A type epoxy acrylate having a number average molecular weight of 7,000 or more and 25,000 or less as a resin precursor, and further, a low molecular weight isocyanate is added as a thermosetting agent. This enhances the resilience. Since the molecular weight is higher than that of Patent Document 1, the flexibility is high to some extent, but as a hard segment, in addition to physical cross-linking by π-π interaction of phenol sites and chemical cross-linking by UV curing, chemical cross-linking by thermosetting It also forms and has a high cohesive force, which ultimately results in inadequate flexibility for this application. In addition, hydroxyl groups and isocyanates, which are the source of the thermosetting reaction, form hydrogen bonds with titanium black, and titanium black tends to aggregate, resulting in poor appearance quality.

On the other hand, as a method for solving the above-mentioned problems, the present inventors reduce the cohesive force of the resin precursor due to physical cross-linking such as π-π interaction and hydrogen bond to the minimum necessary, and these mutuals. By evenly presenting the functional groups forming the action in the resin film composition, the dispersibility of the colorant interacting with the functional groups is increased, and in addition, small and strong chemical crosslinks are formed at a low density by UV curing. As a result, we came up with the idea of imparting concealment without impairing the elasticity and appearance quality, and after diligent studies, we came to the present invention. Hereinafter, the present invention will be described in detail.

It is important that the resin film of the present invention contains the structure of Chemical Formula 1 and the urethane bond, and satisfies all of the following conditions 1 to 4.

In addition, R ^{1 of the} chemical formula 1 refers to a hydrogen or a methyl group.

Condition 1: The resin film contains a colorant.

Condition 2: The total light transmittance measured by the method specified in JIS K7375 (2008) of the resin film is 2% or more and 20% or less.

Condition 3: The storage elastic modulus of the resin film at a temperature of 25 ° C. and a frequency of 1 Hz is 0.5 MPa or more and 50 MPa or less.

Condition 4: Loss tangent of the resin film at 25 ° C is 0.5 or less.

It can be investigated by various analytical methods that the resin film contains the above-mentioned structure and bond, but FT-ATR-IR (Fourier transform infrared spectrophotometer) and pyrolysis GC-MS (gas chromatograph mass) The method by analysis) is simple. It can also be judged from the raw material that forms the resin film.

When the resin film has the above structure and bond, it is possible to form a crosslink and impart resilience, and when the crosslink is present, a urethane bond having high polarity and showing affinity with a colorant is formed. , Can be evenly present without agglomeration.

It is more preferable that the structure of the chemical formula 1 includes the structure of the chemical formula 2.

^{R 1 in} Chemical Formula 2 refers to a hydrogen or methyl group.

^{R 2 of} Chemical Formula 2 refers to any of the following.
-Substituted or unsubstituted alkylene group,
-Substituted or unsubstituted arylene group,
-The alkylene group having an ether group, an ester group, or an amide group inside,
An arylene group having an ether group, an ester group, or an amide group inside,
• An unsubstituted alkylene group having an ether group, an ester group, or an amide group inside.
-Unsubstituted arylene group having an ether group, an ester group, or an amide group inside.

The urethane-bonded segment preferably contains the structure represented by Chemical Formula 3.

In addition, R ^{3 of the} chemical formula 3 refers to any of the following.
-Substituted or unsubstituted alkylene group,
-Substituted or unsubstituted allylene group.

It is important that the resin film of the present invention contains a colorant.

The inclusion of a colorant in a resin film can be investigated by various analytical methods, but the cross section of the film SEM (cross-section observation with a scanning electron microscope) and TOF-SIMS (time-of-flight secondary ion mass spectrometry) The method according to is simple. The measuring method will be described later.

When the resin film contains a colorant, the resin film can be colored and concealing property can be imparted.

It is important that the resin film of the present invention has a total light transmittance of 2% or more and 20% or less specified in JIS K7375 (2008).

When the total light transmittance of the resin film is 2% or more and 20% or less, the hiding property of the film is sufficient, and curing defects due to UV irradiation can be suppressed. From the same viewpoint, the total light transmittance of the resin film is preferably 5% or more and 10% or less.

The total light transmittance refers to the value measured by the haze meter, and the measuring method will be described later.

It is important that the resin film of the present invention has a storage elastic modulus of 0.5 MPa or more and 50 MPa or less at a temperature of 25 ° C. and a frequency of 1 Hz. When the storage elastic modulus is 0.5 MPa or more, it is possible to prevent the tack from being too strong and difficult to handle, and when it is 50 MPa or less, the resin film can be easily deformed. From the same viewpoint, it is preferably 1.0 MPa or more and 25 MPa or less, and more preferably 3.0 MPa or more and 10 MPa or less.

It is important that the resin film of the present invention has a loss tangent of 0.5 or less at 25 ° C.

By setting the loss tangent to 0.5 or less, sufficient resilience can be obtained when used as a resin film. From the same viewpoint, the loss tangent of the resin film at 25 ° C. is preferably 0.2 or less, more preferably 0.05 or less.

The storage elastic modulus and the loss tangent refer to the values measured by the DMA (Dynamic Mechanical Analysis) method, and the measurement method will be described later.

By satisfying the above conditions 3 and 4, both elasticity and resilience can be achieved. As the mechanism, it is presumed that the physical cross-linking that occurs between the resin precursors is suppressed to the minimum necessary level, the resilience is exhibited based on the chemical cross-linking, and the original elasticity of the resin precursor having a high molecular weight can be maintained. .. Further, by satisfying the conditions 1 and 2 at the same time, it is possible to impart concealment without impairing the elasticity and appearance quality. As the mechanism, it is presumed that the colorant exists in a dispersed manner without agglomerating at the physically cross-linked site of the resin precursor, and concealing property can be imparted thereto.

The resin film of the present invention preferably contains a pigment and satisfies condition 5.

Condition 5: The occupied area ratio of the pigment in the cross section of the resin film is 0.1% or more and 2.0% or less.

The occupied area ratio of the pigment in the cross section of the resin film can be calculated by analyzing the SEM image of the cross section of the film, and the method will be described later.

Regarding the occupied area ratio, a small occupied area ratio means that the content of the colorant in the resin film is small. When the occupied area ratio is 2.0% or less, the content of the pigment in the resin film is small and the formation of coarse particles can be suppressed, and when it is 0.1% or more, the weather resistance is high. Even in a moist heat environment, the concealment property can be stably maintained. From the same viewpoint, it is more preferable that the occupied area ratio of the pigment in the cross section of the resin film is 0.2% or more and 1.0% or less.

The resin film of the present invention preferably contains a pigment and satisfies condition 6.

Condition 6: at 30% to 70% of the area in the thickness direction from the surface of the resin film, the thickness direction a ratio of 95% particle size of the pigment _{(D 95)} and 50% particle diameter _{(D 50) F A,} from the surface 0% to 30%, and, at 70% to 100% of the area, when the ratio of _{D 95} and _{D 50} of the pigment was _{F B,} satisfies Equations 1 and 2.

Equation 1: F _A <2.4
Equation _{2: | F A -F B |} <0.4
The particle size of the pigment contained in the resin film can be calculated by analyzing the SEM image of the cross section of the film, and the method will be described later.

Here, F _A of the formula 1, in the interior side of the film, is a parameter indicating the spread of the particle size distribution, this value is preferably smaller than 2.4, more it is less than 2.2 preferable.

To be less than 2.4 F _A of Formula 1, for example, the proportion of coarse particles can be achieved by a smaller, namely that F _A of Formula 1 is to be less than 2.4 , It is possible to suppress streaks and cissing when producing a resin film.

The left side of Equation 2 is a parameter indicating the difference in the spread of the particle size distribution between the inner side and the front side of the film, and this value is preferably smaller than 0.4 and smaller than 0.3. Is more preferable.

When the value on the left side of the value of Equation 2 is smaller than 0.4, it means that the difference in the spread of the particle size distribution in the thickness direction is small, and the value on the left side of the value of Equation 2 is smaller than 0.4. Can be achieved, for example, by increasing the stability of the particles. That is, by making the value on the left side of the value of Equation 2 smaller than 0.4, the formation of coarse particles can be suppressed, and streaks and cissing can be suppressed during the production of the resin film.

In the resin film of the present invention, it is preferable that the pigment is a black pigment. Black pigments include carbon compounds such as carbon black, graphite, fullerene, carbon fiber, and carbon nanotube (CNT), titanium black, aniline black, perylene black, manganese oxide, ferrous oxide, cupric oxide, and cobalt oxide. , Vismus oxide, chromium oxide, magnetite and other inorganic oxides. Further, when the black pigment exceeds 50% by mass with respect to the total amount of the contained pigment, a pigment other than black can also be used. By setting the black pigment to 50% by mass or more, the efficiency of imparting the hiding property of the film can be increased.

The resin film of the present invention preferably satisfies condition 7.

Condition 7: The absorption coefficient (ε _A ) of the resin film satisfies the formula 3.

Equation 3: ε _A (1 / μm) = 100 × (Log ₁₀ 100 / T) / (A × d)> 2.0
However, A is the occupied area ratio (%) of the black pigment, d is the thickness of the resin film (μm), and T is the total light transmittance (%) of the resin film.

Here, the extinction coefficient (ε _A ) of the formula 3 is a parameter indicating the hiding property imparting efficiency of the pigment, and in order to make this value larger than 2.0, for example, the type of colorant or the type of resin precursor. This can be achieved by appropriately adjusting the method for producing the resin film and reducing the total light transmittance to a small value with a small pigment content. That is, by setting the extinction coefficient (ε _A ) of the formula 3 to be larger than 2.0, the hiding property can be ensured with a small pigment content, and a resin film having excellent hiding property and quality can be obtained. be able to. From the same point of view, it is more preferable that this value is larger than 4.0.

Further, the laminate of the present invention is a laminate having a support base material on at least one surface of the resin film, and the peeling force between the support base material and the resin film is 1 N / 50 mm or less. Is preferable. An example thereof is shown in FIG.

Here, the supporting base material is a coating composition for forming a resin film by a method for producing a resin film, which will be described later, when a resin film is provided on one surface of the laminate of the present invention. An in-plane flat article that can be deployed on the surface.

The reason why the support base material is provided in the laminate of the present invention is that in the method for producing a resin film described later, a liquid coating composition is applied onto the support base material and crosslinked to form a resin film. This is to ensure workability and transportability in the post-process after the resin film is processed. Therefore, it is not particularly limited as long as it can be peeled from the resin film (preferably the peeling force from the resin film is 1 N / 50 mm or less) and does not affect the functions including the post-processability of the resin film, as shown in FIG. It is preferable that the laminate 4 has a support base material 7 including a release layer 6 between the laminate 4 and the resin film 5.

Further, when the laminated body is wound into a roll to form an intermediate product, in order to stabilize the rolled shape of the roll, the laminated body 8 has a release layer 10 on the opposite side of the resin film 9 as shown in FIG. It may have a supporting base material 11 including. Of course, as shown in FIG. 4, the laminate 12 may have a release layer 14 between the laminate 12 and the resin film 13, and a support base material 16 including the release layer 15 on the opposite side. In this case, the release layer 14 and the release layer 15 may be the same, but the peeling force between the resin film 9 and the release layer 15 when unwinding the laminate from the roll, and the resin film and 13 in the subsequent step. Since it is necessary to adjust the peeling force between the release layer 14 and the release layer 14, different ones are preferable.

Further, in order to improve the transportability of the resin film in the process and prevent scratches, as shown in FIG. 5, the laminate 17 has a peelable support base material 19 on one surface of the resin film 18 on the other surface. It may have a peelable protective material. The protective material and the support base material may be the same, but as shown in FIG. 6, the laminate 21 has the support base material 24 including the release layer 23 between the protective material and the resin film 22, and the protective material 25. As shown in FIG. 7, the laminate 26 may have a support base material 29 including a release layer 28 and a protective material 31 including a release layer 30 between the laminate 26 and the resin film 27. Often, as shown in FIG. 8, the laminate 32 may have a support base material 35 including a release layer 34 and a protective material 37 including an adhesive layer 36 between the laminate 32 and the resin film 33. Whether the laminate has a protective material having an adhesive layer or a protective material using a release layer is appropriately selected from the suitability of the post-process and the physical characteristics of the resin film.

As described above, in the laminate of the present invention, the peeling force between the supporting base material and the resin film is preferably 1N / 50mm or less, preferably 800mN / 50mm or less. The lower limit of the peeling force between the supporting base material and the resin film is not particularly limited, but if it is less than 10 mN / 50 mm, the supporting base material and the resin film may be peeled off or floated in the manufacturing process. The peeling force between the material and the resin film is preferably 10 mN / 50 mm or more.

The method for measuring the peeling force between the supporting base material and the resin film will be described later.

Further, the display member of the present invention preferably contains the resin film. Further, the health care sensor of the present invention preferably contains the resin film. With these aspects, it is possible to obtain a high-quality display member and healthcare sensor with less color unevenness.

Here, the display member is an electronic device such as a television, a smartphone, or a personal computer that displays an image, and also an electronic device such as a touch panel that has an input function in the device at the same time, and a device using them. include.

In addition to the electronic devices such as the display members mentioned above, healthcare sensors are living organisms such as respiratory rate, heart rate, body temperature, and blood pressure, electrocardiogram, and brain waves for the purpose of maintaining health and improving the quality of medical care. It refers to sensors that continuously record information by attaching it directly to the living body, and devices that use them.

[Mode of the present invention]
Hereinafter, embodiments of the present invention will be specifically described.

[Resin film]
The resin film of the present invention is not particularly limited in the number of layers as long as it has a film-like structure by itself, and may be formed from one layer or two or more layers. It may have been done. Here, the layer refers to a portion having a boundary surface distinguishable from the adjacent portion and having a finite thickness in the thickness direction. More specifically, it refers to a resin film that is distinguished by the presence or absence of a discontinuous interface when the cross section of the resin film is observed with an electron microscope (transmission type, scanning type) or an optical microscope. Even if the composition changes in the thickness direction of the resin film, if the above-mentioned boundary surface does not exist between them, it is treated as one layer.

The resin film of the present invention has glossiness, fingerprint resistance, moldability, designability, scratch resistance, stain resistance, and solvent resistance, in addition to its problems of flexibility, resilience, concealment, and appearance quality. It may have other functions such as antireflection, antistatic, conductivity, heat ray reflection, near infrared absorption, electromagnetic wave shielding, easy adhesion, and in that case, one or more layers may be further formed. .. For example, a functional layer having the above-mentioned functions, an adhesive layer, an electronic circuit layer, a printing layer, an optical adjustment layer, or the like or another functional layer may be provided.

When the resin film of the present invention has a multilayer structure, the formulas 1 and 2 of the condition 6 are calculated for each of the layers having the pigment in the resin film with respect to the above-mentioned condition 6, and at least one of the layers having the pigment is calculated. When one or more layers satisfy the formulas 1 and 2 of the condition 6, the resin film satisfies the condition 6.

The thickness of the resin film is not particularly limited, and is appropriately selected depending on the intended use. The lower limit of the thickness of the resin film is not unconditionally determined because it is affected by the elastic modulus of the resin film itself, the elongation at break, the peeling force between the supporting base material and the resin film, the peeling angle, etc. When the physical properties equivalent to those of general flexible materials are to be realized by using the above manufacturing method, the lower limit is about several μm.

[Laminate]
The laminate of the present invention is a laminate having a support base material on at least one surface of the resin film exhibiting the above-mentioned physical properties, and the peeling force between the support base material and the resin film is 1 N / 50 mm or less. It is preferable, as long as it is in this aspect, the laminated body may be in a flat state or may have a three-dimensional shape after being molded.

[Supporting base material]
The supporting base material used in the laminate of the present invention may be either a thermoplastic resin or a thermosetting resin, may be a homoresin, may be copolymerized, or may be a blend of two or more kinds. .. The resin constituting the support base material is preferably good as long as it has good moldability, and from that point, a thermoplastic resin is more preferable.

Examples of thermoplastic resins preferably used for supporting substrates include polyolefin resins such as polyethylene, polypropylene, polystyrene, and polymethylpentene, alicyclic polyolefin resins, polyamide resins such as nylon 6 and nylon 66, aramid resins, and polyimides. Resin, polyester resin, polycarbonate resin, polyarylate resin, polyacetal resin, polyphenylene sulfide resin, ethylene tetrafluoride resin, ethylene trifluoride resin, ethylene trifluoride chloride resin, ethylene tetrafluoride-6 propylene fluoride copolymer -Fluorine resin such as vinylidene fluoride resin, acrylic resin, methacrylic resin, polyacetal resin, polyglycolic acid resin, polylactic acid resin and the like can be used.

As an example of the thermosetting resin preferably used for the supporting base material, a phenol resin, an epoxy resin, a urea resin, a melamine resin, an unsaturated polyester resin, a polyurethane resin, a polyimide resin, a silicone resin and the like can be used. The thermoplastic resin is preferably a resin having sufficient stretchability and followability. From the viewpoint of strength, heat resistance, and transparency, the thermoplastic resin is more preferably a polyester resin, a polycarbonate resin, an acrylic resin, or a methacrylic resin.

The polyester resin preferably used as a support base material is a general term for polymers having an ester bond as a main bond chain of a main chain, and is obtained by polycondensation of an acid component and an ester thereof and a diol component. Specific examples include polyethylene terephthalate, polypropylene terephthalate, polyethylene-2,6-naphthalate, polybutylene terephthalate and the like. Further, these may be copolymerized with another dicarboxylic acid as an acid component or a diol component and an ester or diol component thereof. Among these, polyethylene terephthalate and polyethylene-2,6-naphthalate are particularly preferable in terms of transparency, dimensional stability, heat resistance and the like.

Further, various additives such as antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, organic particles, thickeners, heat stabilizers, lubricants, infrared absorbers, ultraviolet absorbers, and refractive indexes are used as supporting substrates. A dope agent or the like for adjusting the rate may be added.

Further, the supporting base material may have either a single-layer structure or a laminated structure.

Further, on the surface of the supporting base material, a functional layer such as an easy-adhesion layer, an antistatic layer, an undercoat layer, an ultraviolet absorbing layer, and a release layer can be provided in advance in addition to the resin film of the present invention. In the laminate of the present invention, it is preferable to have a release layer in order to reduce the peeling force between the supporting base material and the resin film. Details of the release layer will be described later.

Examples of supporting base materials provided with a release layer are "Therapeutics" (registered trademark) manufactured by Toyobo Processing Co., Ltd., "Unipee" (registered trademark) manufactured by Unitika Co., Ltd., and "Panapeel" manufactured by Panac Co., Ltd. (Registered trademark), "Toyobo Ester" (registered trademark) manufactured by Toyobo Co., Ltd., "Purex" (registered trademark) manufactured by Teijin Co., Ltd., and the like, and these products can also be used.

It is also possible to apply various surface treatments to the surface of the supporting base material before forming the resin film. Examples of surface treatments include chemical treatments, mechanical treatments, corona discharge treatments, flame treatments, ultraviolet irradiation treatments, high frequency treatments, glow discharge treatments, active plasma treatments, laser treatments, mixed acid treatments and ozone oxidation treatments. Among these, glow discharge treatment, ultraviolet irradiation treatment, corona discharge treatment and flame treatment are preferable, and glow discharge treatment and ultraviolet treatment are more preferable.

[Release layer]
The supporting base material used in the laminate of the present invention preferably has a release layer as described above. A supporting base material having a release layer is also called a release film. The release layer may be composed of a plurality of layers from the viewpoint of imparting adhesion, antistatic property, solvent resistance, etc., or may be on both sides of the supporting base material.

The composition and thickness of the release layer are not particularly limited as long as the release force from the resin film can be within the above-mentioned preferable range, but 10 to 10 in terms of in-plane uniformity, appearance quality, and release force of the release layer. It is preferably 500 nm, more preferably 20 to 300 nm.

[Protective material]
The laminate of the present invention may have a protective material on the surface opposite to the supporting base material of the resin film as shown in FIG. To distinguish between the protective material and the supporting base material, in the method for producing the laminate, the one coated with the coating composition is used as the supporting base material, and the one bonded after forming the resin film is used as the protective material. The protective material may be the same as or different from the above-mentioned support base material, but it is preferable that the protective material has a difference in peeling force from the above-mentioned support base material in use in a subsequent process. The magnitude relationship between the protective material and the peeling force of the supporting base material from the resin film is appropriately selected according to the method of use in the subsequent process. Therefore, the protective material may have a release layer as shown in FIG. 7, may have an adhesive layer as shown in FIG. 8, and may not have a layer as shown in FIG. ..

[Manufacturing method of resin film]
The method for producing the resin film of the present invention is not particularly limited, but a coating composition containing a resin precursor containing a segment of Chemical Formula 3 or 4 is applied onto a supporting substrate to form a coating layer (step 1). Then, the solvent is removed from the coating layer, dried (step 2), irradiated with active energy rays, and the resin precursor is crosslinked (step 3) to prepare a laminate, and the supporting base material is obtained from the laminate. It is preferable to peel off (step 4).

The method of applying the coating composition to the supporting base material in step 1 is not particularly limited as long as the coating composition can be applied onto the supporting base material to form an in-plane uniform coating layer. The coating method on the film can be appropriately selected from a dip coating method, a roller coating method, a wire bar coating method, a gravure coating method, a die coating method (US Pat. No. 2,681294) and the like. Here, the coating layer refers to a "liquid layer" formed by the coating process.

The method for removing the solvent in step 2, that is, the drying method is not particularly limited as long as the solvent can be removed from the coating layer formed on the supporting substrate. Examples of the drying method include heat transfer drying (adhesion to high heat objects), convection heat transfer (hot air), radiant heat transfer (infrared rays), and others (microwaves, induced heating). In the manufacturing method of the above, since it is necessary to precisely make the drying rate uniform even in the width direction, a method using convection heat transfer or radiant heat transfer is preferable.

The cross-linking method in step 3 is to carry out a reaction by irradiating the coating layer from which the solvent has been removed with active energy rays after drying to cross-link the coating film.

Cross-linking with active energy rays is preferably electron beam (EB) and / or ultraviolet light (UV) from the viewpoint of versatility. In addition, examples of the type of ultraviolet lamp used when irradiating ultraviolet rays include a discharge lamp type, a flash type, a laser type, and an electrodeless lamp type. When UV curing is performed using a high-pressure mercury lamp which is a discharge lamp type, the illuminance of the ultraviolet rays ^{is preferably 100 to 3,000 (mW / cm 2} ), more preferably 200 to 2,000 (mW / cm ² ), and even more preferably. It is preferable to irradiate ultraviolet rays under the condition of 300 to 1,500 (mW / cm ² ), and the integrated amount of ultraviolet rays ^{is preferably 100 to 3,000 (mJ / cm 2} ), more preferably 200 to 200. Ultraviolet irradiation may be performed under conditions of 2,000 (mJ / cm ² ), more preferably 300 to 1,500 (mJ / cm ^2). Here, the ultraviolet illuminance is the irradiation intensity received per unit area, and changes depending on the lamp output, the emission spectral efficiency, the diameter of the emission valve, the design of the reflector, and the light source distance from the object to be irradiated. However, the illuminance does not change depending on the transport speed. The integrated ultraviolet light amount is the irradiation energy received per unit area, and is the total amount of photons reaching the surface. The integrated light intensity is inversely proportional to the irradiation speed passing under the light source, and is proportional to the number of irradiations and the number of lamps.

The method for peeling the support base material in step 4 is not particularly limited as long as the support base material and the resin film can be uniformly peeled off, but in general, the resin film side is fixed via an adhesive layer or the like. Therefore, a method of peeling off the supporting base material side is preferable.

[Resin precursor]
The resin precursor is not particularly limited as long as it is a compound having a site that can be crosslinked.
A resin precursor containing the structure of Chemical Formula 4 is preferable, and a resin precursor containing the structure of Chemical Formula 5 is more preferable.

As described above, the structures of Chemical Formulas 4 and 5 have a (meth) acrylic group represented by X in the figure at the end, and the (meth) acrylic group (X) at the end can be crosslinked. Corresponds to. Further, the (meth) acrylic group (X) is adjacent to the polyisocyanate residue represented by Y in the figure. Further, the segment of Chemical Formula 4 means that the other end of the polyisocyanate residue represented by Y and the polyol residue (Z) represented by Z in Chemical Formula 4 are adjacent to each other.

The polyisocyanate residues (Y) of chemical formulas 4 and 5 are preferably TDI (tolylene diisocyanate), MDI (4,4'-diphenylmethane diisocyanate), NDI (1,5-naphthalenediocyanate), TODI (trizine diisocyanate). , XDI (xylylene diisocyanate), PPDI (paraphenylenediocyanate), TMXDI (tetramethylxylylene diisocyanate), HMDI (hexamethylene diisocyanate), IPDI (isophorone diisocyanate), H6XDI (hydrogenated xylylene diisocyanate), H12MDI (dicyclohexylmethane) It is a residue of polyisocyanate such as diisocyanate).

The polyol residue of Chemical Formula 5 is preferably a polyester polyol, a polyether polyol, or a polycarbonate polyol.

[Colorant]
The colorant is used to color the resin film, reduce the total light transmittance and impart concealment, and is not particularly limited as long as it can form the resin film exhibiting the characteristics of the present invention, but the above-mentioned laminate It is preferable that the colorant is suitable for the production method of.

The colorant can be divided into a pigment and a dye as shown below, but the pigment is preferable from the viewpoint of hiding efficiency and weather resistance of the resin film.

Pigments include black, white, red, green, blue, yellow, purple, cyan, magenta and the like, and these may be used alone or in combination of two or more. In order to suppress the deterioration of quality due to the generation of aggregates of the colorant, it is preferable to reduce the content of the colorant as much as possible, and it is preferable to use the black pigment alone.

As black pigments, carbon compounds such as carbon black, graphite, fullerene, carbon fiber, carbon nanotube (CNT), titanium black, aniline black, perylene black, manganese oxide, ferrous oxide, cupric oxide, cobalt oxide, etc. Examples thereof include inorganic oxides such as bismuth oxide, chromium oxide, and magnetite. Of these, carbon black is particularly preferable because it has excellent hiding power.

Examples of the white pigment include inorganic oxides such as calcium carbonate, barium sulfate, and titanium dioxide.

Red pigments and magenta pigments are, for example, by color index name, C.I. I. Pigment Red 7, 9, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 57: 1, 81, 81: 1, 81: 2, 81: 3, 81: 4, 122, 123, 146, 155, 166, 168, 176, 177, 178, 180, 184, 185, 187, 200, 202, 208, 209, 210, 217, 220, 224, 242, 246, 254, 255, 264, 270, 272 and 279 and the like.

The green pigment is, for example, a color index name, C.I. I. Pigment Greens 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55 and 58 and the like.

Blue pigments and cyan pigments are, for example, by color index name, C.I. I. Pigment Blue 1, 1: 2, 9, 14, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17, 19, 25, 27, 28, 29, 33, Examples thereof include 35, 36, 56, 56: 1, 60, 61, 61: 1, 62, 63, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78 and 79.

The yellow pigment is, for example, a color index name, and C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 126, 127, 128, 129, 138, 139, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 184, 185, 187, 188, 193, 194, 198, 199, 213 and 214 and the like can be mentioned.

Examples of the dye include a metal complex salt black dye such as an azo dye and an organic compound such as an anthraquinone compound.

[Paint composition]
The "paint composition" used in the method for producing a laminate of the present invention is not particularly limited as long as it can be uniformly applied in-plane on the supporting base material and a resin film exhibiting the characteristics of the present invention can be formed. It is preferable that the coating composition is suitable for the above-mentioned method for producing a laminate. Specifically, it is preferable to add the above-mentioned resin precursor, a solvent, a colorant, and other components described later to prepare a coating composition. Further, when using a colorant having poor dispersibility in a coating composition such as a pigment, it is preferable to disperse the pigment in two steps. Specifically, a "pigment dispersion" is once produced by adding and dispersing the pigment to the resin precursor and the solvent so that the concentration is higher than the amount of the pigment added used in this application, and then the resin is used. It is more preferable to obtain a coating composition by diluting with a precursor and a solvent.

[solvent]
The coating composition used in the method for producing a laminate of the present invention may contain a solvent, and it is preferable to contain a solvent in order to uniformly form the coating layer in the plane. The number of types of the solvent is preferably 1 type or more and 20 types or less, more preferably 1 type or more and 10 types or less, further preferably 1 type or more and 6 types or less, and particularly preferably 1 type or more and 4 types or less. Here, the "solvent" refers to a substance that is liquid at normal temperature and pressure and can evaporate almost the entire amount in the above-mentioned drying step.

Here, the type of solvent is determined by the molecular structure constituting the solvent. That is, those having the same element composition and having the same type and number of functional groups but different bonding relationships (structural isomers) are not the structural isomers, but what kind of conformation is used in the three-dimensional space. Those that do not exactly overlap even if they are taken (stereoisomers) are treated as different types of solvents. For example, 2-propanol and n-propanol are treated as different solvents.

[Other components in the paint composition]
The coating composition used in the method for producing a laminate of the present invention preferably contains an antioxidant, a polymerization initiator, a curing agent and a catalyst. Polymerization initiators and catalysts are used to promote cross-linking of resin films. As the polymerization initiator, those capable of initiating or promoting polymerization, condensation or cross-linking reaction of the components contained in the coating composition by an anion, cation, radical polymerization reaction or the like are preferable.

Antioxidants are roughly classified into radical chain initiation inhibitors, radical scavengers, and peroxide decomposing agents according to their mechanism of action, and the effects of the present invention can be obtained by any of these for suppressing deterioration under high temperature conditions. However, a radical scavenger or a peroxide decomposing agent is more preferable, and a hindered phenol-based or semi-hindered phenol-based radical scavenger, or a phosphite-based or thioether-based peroxide decomposing agent is more preferable. Further, when carbon black is used for imparting concealing property, it is more preferable to include a hindered phenol-based radical scavenger in order to improve the dispersibility of carbon black.

Various polymerization initiators, curing agents and catalysts can be used. Further, the polymerization initiator, the curing agent and the catalyst may be used individually, or a plurality of polymerization initiators, the curing agent and the catalyst may be used at the same time. Further, an acidic catalyst or a thermal polymerization initiator may be used in combination. Examples of acidic catalysts include hydrochloric acid aqueous solution, formic acid, acetic acid and the like. Examples of the thermal polymerization initiator include peroxides and azo compounds. Examples of the photopolymerization initiator include alkylphenone-based compounds, sulfur-containing compounds, acylphosphine oxide-based compounds, and amine-based compounds. Examples of the cross-linking catalyst that promotes the urethane bond formation reaction include dibutyltin dilaurate and dibutyltin diethylhexoate.

As the photopolymerization initiator, it is preferable to use an alkylphenone-based compound and an acylphosphine oxide-based compound in combination from the viewpoint of curability. Specific examples of the alkylphenone-type compound include 1-hydroxy-cyclohexyl-phenyl-ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1- (4-methylthiophenyl)-. 2-Morphorinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-phenyl) -1-butane, 2- (dimethylamino) -2-[(4-methylphenyl) methyl]- 1- (4-Phenyl) -1-butane, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butane, 2- (dimethylamino) -2-[(4-methylphenyl) ) Methyl] -1- [4- (4-morpholinyl) phenyl] -1-butane, 1-cyclohexyl-phenylketone, 2-methyl-1-phenylpropan-1-one, 1- [4- (2-ethoxy) ) -Phenyl] -2-hydroxy-2-methyl-1-propane-1-one, bis (2-phenyl-2-oxoacetic acid) oxybisethylene, and high molecular weight compounds of these materials. .. Specific examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, and high molecular weight materials thereof. Can be mentioned. These may be used alone or in combination of two or more.

Further, a leveling agent, a lubricant, an antistatic agent and the like may be added to the coating composition used for forming the resin film as long as the effects of the present invention are not impaired. As a result, the resin film can contain a leveling agent, a lubricant, an antistatic agent, and the like.

Examples of the leveling agent include an acrylic copolymer or a silicone-based or fluorine-based leveling agent. Examples of the antistatic agent include metal salts such as lithium salt, sodium salt, potassium salt, rubidium salt, cesium salt, magnesium salt and calcium salt.

[Application example]
The resin film of the present invention takes advantage of excellent optical properties, flexibility, elasticity, transportability, and appearance quality, and can be suitably used for applications requiring particularly high flexibility and elasticity.

For example, plastic molded products such as glasses / sunglasses, cosmetic boxes, food containers, water tanks, showcases for exhibitions, smartphone housings, touch panels, color filters, flat panel displays, flexible displays, flexible devices, wearables. Devices, sensors, circuit materials, electrical and electronic applications, keyboards, home appliances such as TV / air conditioner remote controls, mirrors, windowpanes, buildings, dashboards, car navigation / touch panels, vehicle parts such as room mirrors and windows, and various It can be suitably used for each surface material, internal material, constituent material, manufacturing process material, etc., such as printed matter, medical film, sanitary material film, medical film, agricultural film, and building material film. By using the resin film of the present invention for these materials, the quality thereof can be improved.

Next, the present invention will be described based on examples, but the present invention is not necessarily limited thereto.
"Synthesis of resin precursors"
The raw materials used in the synthesis of resin precursors are as follows.

"Diisocyanate"
-IPDI: Isophorone diisocyanate-MDI: 4,4'-diphenylmethane diisocyanate "polyol"
-PBAA-1: Polybutylene adipate manufactured by Tosoh Corporation Nipponolan 3027 (weight average molecular weight 2500)
・ PEAA: Polyethylene glycol adipate manufactured by Tosoh Corporation Nipponlan 4040
(Weight average molecular weight 2000)
EX861: Polyethylene Glycol Diglycidyl Ether "Hydroxyacrylate" manufactured by Nagase ChemteX Corporation
・ HEA: Hydroxyethyl acrylate ・ 4HBA: 4-Hydroxybutylacryllate ・ GMA: Glysidyl methacrylate “Bisphenol A type epoxy compound”
-YD8125: "Succinic anhydride" manufactured by Nittetsu Chemical and Materials Co., Ltd.
-"Ricacid" (registered trademark) SA: manufactured by NEW JAPAN CHEMICAL CO., LTD. [Resin precursor A]
IPDI as diisocyanate, PBAA-1 as polyol, and toluene were placed in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet. At this time, the molar ratio of diisocyanate to polyol was adjusted to 0.43: 0.29, and the solid content concentration was adjusted to 60% by mass. When the reaction was carried out at 90 ° C. and the residual isocyanate group in the unreacted state was 100% by mass, the temperature was lowered to 70 ° C. when the residual isocyanate group became 1.4% by mass due to the reaction, and hydroxyacrylate (HEA) was added. added. At this time, the molar ratio of diisocyanate, polyol, and hydroxyacrylate in the unreacted state was set to 0.43: 0.29: 0.29. When the residual isocyanate group in the unreacted state is 100% by mass, the heating is stopped when the residual isocyanate group becomes 0.3% by mass due to the reaction, the reaction is terminated, and toluene is added to increase the solid content concentration to 60. It was adjusted to mass% to obtain a toluene solution of the resin precursor A.
[Resin precursor B]
IPDI as diisocyanate, PBAA-1 as polyol, and toluene were placed in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet. At this time, the molar ratio of diisocyanate to polyol was adjusted to 0.48: 0.32, and the solid content concentration was adjusted to 60% by mass. When the reaction was carried out at 90 ° C. and the residual isocyanate group in the unreacted state was 100% by mass, the temperature was lowered to 70 ° C. when the residual isocyanate group became 1.4% by mass due to the reaction, and hydroxyacrylate (HEA) was added. added. At this time, the molar ratio of diisocyanate, polyol, and hydroxyacrylate in the unreacted state was set to 0.48: 0.32: 0.20. When the residual isocyanate group in the unreacted state is 100% by mass, the heating is stopped when the residual isocyanate group becomes 0.3% by mass due to the reaction, the reaction is terminated, and toluene is added to increase the solid content concentration to 60. It was adjusted to mass% to obtain a toluene solution of the resin precursor B.
[Resin precursor C]
MDI as diisocyanate, PEAA as polyol, and toluene were placed in a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet. At this time, the molar ratio of diisocyanate to polyol was adjusted to 0.43: 0.29, and the solid content concentration was adjusted to 60% by mass. When the reaction was carried out at 90 ° C. and the residual isocyanate group in the unreacted state was 100% by mass, the temperature was lowered to 70 ° C. when the residual isocyanate group became 1.4% by mass due to the reaction, and hydroxyacrylate (HEA) was added. added. At this time, the molar ratio of diisocyanate, polyol, and hydroxyacrylate in the unreacted state was set to 0.43: 0.29: 0.29. When the residual isocyanate group in the unreacted state is 100% by mass, the heating is stopped when the residual isocyanate group becomes 0.3% by mass due to the reaction, the reaction is terminated, and toluene is added to increase the solid content concentration to 60. It was adjusted to mass% to obtain a toluene solution of the resin precursor C.
[Resin precursor D]
As the resin precursor D, NK oligo (weight average molecular weight 4000) manufactured by Shin-Nakamura Chemical Industry Co., Ltd., which is a bisphenol A type epoxy acrylate, was used.
[Resin precursor E]
64.8 parts of bisphenol A, 57.1 parts of bisphenol A type epoxy compound (YD8125), polyethylene glycol diglycidyl ether (EX861) 128 in a 4-port flask equipped with a thermometer, agitator, water-cooled condenser, and nitrogen gas inlet. .1 part, 1.25 parts of triphenylphosphine and 1.25 parts of N, N-dimethylbenzylamine as a catalyst, and toluene as a solvent were added so that the solid content concentration became 60% by mass. The temperature was raised to 110 ° C. with stirring under a nitrogen stream and reacted for 8 hours to obtain a hydroxy group-containing resin. Next, 54.6 parts of succinic anhydride (“Ricacid” (registered trademark) SA) was added as an acid anhydride, and the mixture was reacted at 110 ° C. for 4 hours. After confirming that the absorption of the acid anhydride group had disappeared by FT-IR measurement, the mixture was cooled to room temperature. Next, in this flask, nitrogen was stopped from the nitrogen introduction tube, the introduction was switched to dry air, 26.0 parts of glycidyl methacrylate (GMA) was added with stirring, and the flask was reacted at 80 ° C. for 8 hours. After completion of the reaction, methyl ethyl ketone was added to adjust the solid content concentration to 50% by mass to obtain a methyl ethyl ketone solution of the resin precursor E.
"Preparation of colorant dispersion"
The colorants and dispersants used are as follows.
"Colorant"
・ "Niteron" (registered trademark) # 10MAF: Carbon black Made by Nittetsu Carbon Co., Ltd. Average particle size 40 nm
"Lumogen" (registered trademark) Black FK4280: Perylene Black BASF, average 30 nm
・ Kayaset Black A-N: Anthraquinone-based black dye manufactured by Nippon Kayaku Co., Ltd. ・ Ciani Blue 5191: Phthalocyanine Blue manufactured by Dainichiseika Co., Ltd. “Dispersant”
BYK111: Dispersant manufactured by Big Chemie Co., Ltd. [Colorant dispersion A]
Add 1 part by mass of carbon black, 0.2 part by mass of BYK111, and 0.5 part by mass of cyani blue to the compounding container, and adjust the solid content concentration to 5% by mass with methyl ethyl ketone to obtain a colorant dispersion A. rice field.
[Colorant dispersion B]
1 part by mass of perylene black, 0.2 part by mass of BYK111, and 0.5 part by mass of cyani blue were added to the compounding container, and the solid content concentration was adjusted to 5% by mass with methyl ethyl ketone to obtain a colorant dispersion liquid B. rice field.
[Colorant dispersion C]
An anthraquinone-based black dye was adjusted to a solid content concentration of 5% by mass with methyl ethyl ketone in a compounding container to obtain a colorant dispersion liquid C.
[Colorant dispersion D]
The colorant dispersion liquid A is added to the compounding container, and the resin precursor A is added thereto so as to be 16 parts by mass with respect to 1 part by mass of carbon black so that the solid content concentration becomes 55% by mass as a whole. Was diluted with methyl ethyl ketone to obtain a colorant dispersion liquid D.
[Colorant dispersion E]
The colorant dispersion liquid A is added to the compounding container, and the resin precursor B is added thereto so as to be 16 parts by mass with respect to 1 part by mass of carbon black so that the solid content concentration becomes 55% by mass as a whole. Was diluted with methyl ethyl ketone to obtain a colorant dispersion E.
[Preparation of paint composition]
The types of resin precursors, colorant dispersions, additives and solid content ratios are as shown in Table 1, and these materials are diluted with methyl ethyl ketone to form a resin film with a solid content concentration of 40% by mass. A coating composition for forming was obtained. In this case, the additive refers to a group consisting of a photopolymerization initiator, a leveling agent, an antioxidant, and a thermosetting agent, and the raw materials used are as follows.
"Additive"
-Photopolymerization initiator A: "IRGACURE" (registered trademark) 184 (manufactured by BASF Japan Ltd.)
-Photopolymerization initiator B: "Omnirad" (registered trademark) TPO (manufactured by IGM Resins)
-Leveling agent A: "Mega Fuck" (registered trademark) F-556 (manufactured by DIC Corporation)
-Antioxidant A: "Irganox" (registered trademark) 1010 (manufactured by BASF Japan Ltd.)
Thermosetting agent A: "Death module" (registered trademark) BL-4265SN (isocyanate equivalent = 337 g / eq) manufactured by Sumika Cobestro Urethane Co., Ltd.
Thermosetting agent B: "Duranate" (registered trademark) E402-B80B (isocyanate equivalent = 560 g / eq) manufactured by Asahi Kasei Chemicals Co., Ltd.

[Paint composition for release layer]
The following materials were mixed and diluted with a methyl ethyl ketone / isopropyl alcohol mixed solvent (mass mixing ratio 50/50) to obtain a coating composition for a release layer having a solid content concentration of 5% by mass.
・ Side chain type carbinol modification reaction type silicone oil (X-22-4015 Shinetsu Chemical Industry Co., Ltd. Solid content concentration: 100% by mass): 5 parts by mass ・ Both terminal type polyether modification reaction type silicone oil (X-22) -4952 Shin-Etsu Chemical Industry Co., Ltd. Solid content concentration: 100% by mass): 5 parts by mass, acrylic-modified alkyd resin solution (Hariftal KV-905 Harima Kasei Co., Ltd. Solid content concentration 53% by mass): 100 parts by mass, isobutyl alcohol modification Melamine resin solution ("Melan" (registered trademark) 2650L Hitachi Kasei Co., Ltd. Solid content concentration 60% by mass): 20 parts by mass, paratoluenesulfonic acid: 5 parts by mass.
[Manufacturing method of laminate and resin film]
[Formation of support base material with release layer]
Using a coating device with a small-diameter gravure coater, a coating composition for a release layer was applied to a polyester film (trade name "Lumirror" (registered trademark) R75X manufactured by Toray Industries, Inc.) with a thickness of 50 μm, and the release layer thickness was about 200 nm. The number of lines of the gravure roll, the peripheral speed of the gravure roll, and the solid content concentration of the coating composition for the release layer were adjusted so as to be applied, and then the hot air temperature was kept at 140 ° C. for 30 seconds to dry. Cross-linking was performed to obtain a support base material with a release layer.
[Method for forming a laminate A]
(Step 1)
As the support base material, the above-mentioned support base material with a release layer is used, and the above-mentioned coating composition is applied onto the release layer of the above-mentioned support base material after cross-linking using a continuous coating device using a slot die coater. The coating layer was formed by adjusting the discharge flow rate and applying the resin film so that the thickness of the resin film became the specified film thickness.

(Step 2)
The coating layer formed in step 1 was dried under the following conditions to remove the solvent.

Blower temperature: Temperature: 50 ° C,
Wind speed: Coating surface side: 5 m / sec, Anti-coating surface side: 5 m / sec Wind direction: Coating surface side: Parallel to the substrate surface, Anti-coating surface side: Vertical to the substrate surface Dwelling time: 2 Minutes (step 3)
In step 2, the coating layer (uncrosslinked resin film) obtained by removing the solvent is crosslinked by irradiating it with active energy rays under the following conditions, and is composed of a supporting base material, a release layer and a resin film. A laminate was obtained.

Irradiation light source: High-pressure mercury lamp Irradiation output: 400 W / cm ²
Integrated light intensity: 120mJ / cm ²
Oxygen concentration: 0.1% by volume.

[Method B for forming a laminated body]
The blast temperature in step 2 was changed to 80 ° C., and the laminated body was obtained in the same manner as in the method A for forming the laminated body under other conditions.

The laminates and resin films of Examples 1 to 8 and Comparative Examples 1 to 4 were prepared by the above method. Table 2 shows the coating composition for forming a resin film corresponding to each Example and Comparative Example, the method for forming the laminate, and the thickness of each resin film.

[Evaluation of resin film and laminate]
The following performance evaluations were carried out on the laminate and the resin film, and the results obtained are shown in Table 2. Unless otherwise specified, in each Example / Comparative Example, one sample was measured three times at different locations, and the average value was used.

[Measurement of storage elastic modulus and loss tangent of resin film]
After cutting the laminate into a rectangle having a width of 10 mm, the supporting base material was peeled off to obtain a test piece.

Storage of resin film based on the tensile vibration-non-resonant method of JIS K7244-4 (1999) (this is referred to as the dynamic viscoelasticity method) using the dynamic viscoelasticity measuring device "DMS6100" manufactured by Seiko Instruments Co., Ltd. The elastic modulus and loss tangent were determined.
Measurement mode: Distance between tension chucks: 20 mm
Width of test piece: 10 mm
Frequency: 1Hz
Strain amplitude: 10 μm
Minimum tension: 20mN
Initial force amplitude: 40 mN
Measurement temperature: From -100 ° C to 200 ° C Temperature rise rate: 5 ° C / min [Measurement of total light transmittance of resin film]
After cutting the laminate into 50 mm squares, the supporting base material was peeled off to obtain a test piece.

Based on JIS K7375 (2008), the total light transmittance of the resin film was determined using a haze meter NDH-5000 manufactured by Nippon Denshoku Co., Ltd.
[Analysis of particle size of colorant contained in resin film]
The particle size analysis of the colorant present in the resin film was performed by SEM observation of the cross section of the film using SEM JSM-6700F manufactured by JEOL Ltd. The procedure for preparing the test piece for cross-section SEM observation was as follows.

1. 1. The resin film side of the laminate was embedded with a UV curable resin. Then, the supporting base material was peeled off, and the same operation was performed.

2. Using a rotary microtome RMS manufactured by Nippon Microtome Co., Ltd., a resin film was cut together with the embedded resin at intervals of 10 μm with respect to the sample TD direction.

3. 3. Using an autofine coater JFC-1600 manufactured by JEOL Ltd., about 10 μm of platinum was vapor-deposited on the cross section of the cut sample (condition: 30 mA × 20 seconds × 2 times) to prepare a test piece.

The conditions for cross-sectional SEM observation were as follows.
Measurement mode: LEI mode Magnification: 5000 times Acceleration voltage: 3kV
WD (sample distance): 8.0 mm
The particle size of the colorant contained in the resin film was analyzed by using the image analysis software ImageJ (developer: National Institutes of Health) for the cross-sectional SEM image according to the following procedure.
1. 1. Trimming and image combination were performed so that the thickness direction of the cross section of the film was included and there was no overlap. In addition, trimming was performed so that a portion unrelated to the cross section of the film was not displayed.
2. The cross-sectional SEM image was converted to 8 bits.
3. 3. For the cross-section SEM image, Smooth and Sharp were performed twice each, and then Find Edge and Smooth were performed once each to emphasize the outline of the image.
4. Brightness / Contrast was used to adjust so that only the colorant particles became white.
5. The whitened part was selected by Threshold and binarized.
6. The particle size of the colorant was analyzed by Analyz Particles. At this time, Ellipses was selected on the show tab, and ellipse approximation was performed.
7. The above image analysis was performed on the cross-sectional SEM images of three samples, and the occupied area ratio, the major axis and the minor axis of each particle were calculated. Further, the particle size of each particle of the colorant was defined as (major axis + minor axis) / 2.
8. To produce a frequency distribution of the particle size of the analyzed colorant, the closest particle diameter frequency 50% D _50, the closest particle diameter frequency 95% was defined as D _95.
9. Using the following equation, the value from the _{F A D 50} of the _{D 95} at 30% to 70% of the area of the thickness of the resin film, 0% to 30% of the thickness of the resin film, at 70% to 100% of the area the _{F B} from the value of D ₅₀ and _{D 95,} were calculated, respectively.

_{F A = D 95 (30%} ~70% _{area) / D 50 (30% ~70} % area)
_{F B = D 95 (0%} ~30%, 70% ~100% _{area) / D 50 (0% ~30} %, 70% ~100% area)
[Measurement of resin film thickness]
The arithmetic mean value of the thickness obtained from the above cross-sectional SEM image was taken as the thickness of the resin film.

[Peeling force between supporting base material and resin film]
In the laminated body, the resin film and the supporting base material were slightly peeled off from the edges in advance to form a gripping margin for measurement with a tensile tester (Tencilon UCT-100 manufactured by Orientec). Next, the resistance value (N) when peeled by 180 degrees at a speed of 1200 (mm / min) was measured using a tensile tester in an environment of 23 ° C. and 65% RH. The resistance value (N) was divided by the width (mm) of the supporting base material and the resin film, then multiplied by 50, and converted into a peeling force (N / 50 mm) corresponding to each width of 50 mm.

[Evaluation of resin film flexibility]
After cutting the laminate into a rectangle having a width of 10 mm and a length of 150 mm, the resin film was peeled off from the supporting base material to obtain a test piece. The direction of each 150 mm length was aligned with the longitudinal direction of the resin film. Using a tensile tester (Tencilon UCT-100 manufactured by Orientec), the initial tensile chuck distance was set to 50 mm, the tensile speed was set to 300 mm / min, and the tensile test was performed at a measurement temperature of 23 ° C.

The load b (N) applied to the sample when the distance between the chucks was a (mm) was read, and the strain amount x (%) and the stress y (N / mm ² ) were calculated from the following equations. However, the sample thickness before the test is k (mm).
Strain amount: x = ((a-50) / 50) x 100
Stress: y = b / (k × 10).

Among the data obtained above, the stress at a strain amount of 5% was defined as 5% strain stress, and 5 MPa or less was regarded as acceptable.

[Evaluation of resilience of resin film]
The resin film was cut into a rectangle having a width of 10 mm and a length of 150 mm and used as a test piece. The direction of each 150 mm length was aligned with the longitudinal direction of the resin film. Using a tensile tester (Tencilon UCT-100 manufactured by Orientec), evaluation was performed under two conditions with different deformation rates in order to see the superiority and inferiority of resilience at a measurement temperature of 23 ° C.

Condition A: Initial chuck distance 50 mm, tensile speed 50 mm / min After stretching the sample to a strain amount of 100%, the tensile load on the sample is released, and the distance marked as the initial test length before measurement is measured and L mm. As a result, the elastic recovery rate z ₁ (%) and the shear rate s ₁ (s ^-1 ) were calculated from the following equations.

Elastic recovery rate z ₁ = (1- (L-50) / 100) × 100 (%).

Shear velocity s ₁ = (50/60) / ^{10 = 0.08 (s -1} )
Condition B: Initial chuck distance 50 mm, tensile speed 300 mm / min After stretching the sample to a strain amount of 100%, the tensile load on the sample is released, and the distance marked as the initial test length is measured before measurement. As L mm, the elastic recovery rate z ₁ % was calculated from the following formula.

Elastic recovery rate z ₂ = (1- (L-50) / 100) × 100 (%).

Shear velocity s ₁ = (50/60) / ^{10 = 0.08 (s -1} )
In the above evaluation, a condition A of 90% or more and a condition B of 70% or more were regarded as acceptable.

[Evaluation of concealment of resin film]
The hiding property of the film was carried out by the following two methods, and those that passed at least Condition A were regarded as passing.

Condition A: Five 40 mm lines at 5 mm intervals using a black magic pen (Tombo Pencil Co., Ltd. oil-based twin marker extra-fine monotwin E black) on general-purpose white thick paper (HSK ivory manufactured by Hisada Shoeidou Co., Ltd.) The above-mentioned white thick paper and resin film are placed in this order on a light box equipped with a high-color-enhancing fluorescent lamp (40W), and visually observed from above while exposing, and the line spacing of the black marker cannot be recognized. The case was passed.

Condition B: After cutting the laminate into 50 mm squares, the supporting base material is peeled off to make a test piece, and after measuring the total light transmittance by the above method, a constant temperature constant chamber tank LHL-113 manufactured by ESPEC CORPORATION is used. It was stored for one week in the moist heat environment (85 ° C., 85% RH) used. Then, after standing for 1 hour or more in an atmosphere of 23 ° C. and 65% RH, the total light transmittance was measured again, and the rate of change was determined.
[Evaluation of appearance quality of resin film]
The resin film was visually observed, ^{and based on the number of defects appearing in the produced resin film 1 m 2} , the following points were given and evaluated.

5 points: Number of defects of 10 mm or less is 3 or less 4 points: Number of defects of 10 mm or less is 3 or more and 5 or less 3 points: Number of defects of 10 mm or less is 5 or more and 7 or less 2 points: Number of defects of 10 mm or less 7 or more and 10 or less 1 point: 10 or more defects of 10 mm or less, or 1 or more defects of 10 mm or more.

Table 3 shows the structure of the chemical formula 1 of the resin film and the presence / absence of urethane bonds, Table 4 shows the evaluation results of the above-mentioned conditions 1 to 6, and Table 5 shows the flexibility, stability, and hiding property of the resin film. The evaluation results of appearance quality are summarized.

In Table 3, the meaning of "included" in the column of the structure of the chemical formula 1 means that each example or the like includes the structure of the chemical formula 1, and the meaning of "not included" means that each example or the like includes the chemical formula or the like. It means that the structure of 1 is not included. The same applies to the urethane bond.

1, 4, 8, 12, 17, 21, 26, 32: Laminated body 2, 5, 9, 13, 18, 22, 27, 33: Resin film 6, 10, 14, 15, 23, 28, 30, 34: Release layer 3, 7, 11, 16, 19, 24, 29, 35: Support base material 20, 25, 31, 37: Protective material 36: Adhesive layer

The resin film of the present invention takes advantage of excellent optical properties, flexibility, elasticity, transportability, and appearance quality, and can be suitably used for applications requiring particularly high flexibility and elasticity.

For example, plastic molded products such as glasses / sunglasses, cosmetic boxes, food containers, water tanks, showcases for exhibitions, smartphone housings, touch panels, color filters, flat panel displays, flexible displays, flexible devices, wearables. Devices, sensors, circuit materials, electrical and electronic applications, keyboards, home appliances such as TV / air conditioner remote controls, mirrors, windowpanes, buildings, dashboards, car navigation / touch panels, vehicle parts such as room mirrors and windows, and various It can be suitably used for each surface material, internal material, constituent material, manufacturing process material, etc., such as printed matter, medical film, sanitary material film, medical film, agricultural film, and building material film.

Claims (8)

A resin film containing the structure of Chemical Formula 1 and a urethane bond and satisfying all of the following conditions 1 to 4.

In addition, R ^{1 of the} chemical formula 1 refers to a hydrogen or a methyl group.
Condition 1: The resin film contains a colorant.
Condition 2: The total light transmittance measured by the method specified in JIS K7375 (2008) of the resin film is 2% or more and 20% or less.
Condition 3: The storage elastic modulus of the resin film at a temperature of 25 ° C. and a frequency of 1 Hz is 0.5 MPa or more and 50 MPa or less.
Condition 4: Loss tangent of the resin film at 25 ° C is 0.5 or less. The resin film according to claim 1, which contains a pigment and satisfies the condition 5.
Condition 5: The occupied area ratio of the pigment in the cross section of the resin film is 0.1% or more and 2.0% or less. The resin film according to claim 1 or 2, which contains a pigment and satisfies the following condition 6.
Condition 6: at 30% to 70% of the area in the thickness direction from the surface of the resin film, the thickness direction a ratio of 95% particle size of the pigment _{(D 95)} and 50% particle diameter _{(D 50) F A,} from the surface 0% to 30%, and, at 70% to 100% of the area, when the ratio of the average values of D95 and D50 of the pigment was _{F B,} satisfies Equations 1 and 2.
Equation 1: F _A <2.4
Equation _{2: | F A -F B |} <0.4 The resin film according to any one of claims 1 to 3, wherein the pigment is a black pigment. The resin film according to claim 4, which satisfies the condition 7.
Condition 7: The absorption coefficient (ε _A ) of the resin film satisfies the formula 3.
Equation 3: ε _A (1 / μm) = 100 × (Log ₁₀ 100 / T) / (A × d)> 2.0
However, A is the occupied area ratio (%) of the black pigment, d is the thickness of the resin film (μm), and T is the total light transmittance (%) of the resin film. A laminate having a support base material on at least one surface of the resin film according to any one of claims 1 to 5, wherein the peeling force between the support base material and the resin film is 1 N / 50 mm or less. A laminate. A display member containing the resin film according to any one of claims 1 to 5. A health care sensor comprising the resin film according to any one of claims 1 to 5.

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