WO2018061910A1

WO2018061910A1 - Method for manufacturing molded body

Info

Publication number: WO2018061910A1
Application number: PCT/JP2017/033838
Authority: WO
Inventors: 彰人佐部利; 昭弘池山; 横山　和正
Original assignee: 富士フイルム株式会社
Priority date: 2016-09-29
Filing date: 2017-09-20
Publication date: 2018-04-05
Also published as: CN109803809B; JP6629701B2; CN109803809A; KR102178544B1; KR20190049759A; JP2018051936A

Abstract

Provided is a method for manufacturing a molded body that has superior transparency, processability, and formability while still suppressing the occurrence of coloring. A method for manufacturing a molded body (10) has a film-material forming step (33) and a molding step (32). In the film-material forming step (33), an elongated film material is formed from cellulose acylate. In the molding step (32), the obtained film material (20) and a substrate material (22) formed of a thermoplastic resin are integrally molded thereby forming the molded body (10) having a cellulose acylate film (13) and a transparent substrate (11) by thermoforming at a forming temperature in the range of 150-240°C inclusive.

Description

Manufacturing method of molded body

The present invention relates to a method for producing a molded body.

ガラス Glass is often used in molded products that require transparency, such as surveillance camera covers and incubator cases. And when impact resistance and / or workability are further required, synthetic resin such as acrylic or polycarbonate is used instead of glass.

As a method for producing a molded body, for example, JP-A-6-143339 describes a method for producing swimming goggles as a molded body. The molded body has a transparent base material as the molded body and a lens provided with an antifogging layer as an antifogging film, and the transparency may decrease due to fogging due to condensation. It is suppressed. The base material is preliminarily molded into a shape having a hole for mounting a lens, using a transparent thermoplastic resin such as polycarbonate. The lens has a base material placed in an injection mold, and is injected into the mold in a molten state of a thermoplastic transparent cellulose resin such as triacetyl cellulose. Formed. The mold temperature as the molding temperature is set to 70 ° C. to 85 ° C. The film having antifogging properties is formed by subjecting the lens surface to a saponification treatment as a hydrophilic treatment.

JP-A-2009-139964 describes a method for producing an optical composite molded article that is used as a lens such as goggles and has a base material and a polarizing composite sheet. The polarizing composite sheet has a cellulose triacetate film, a polarizing film, an adhesive layer, and a polycarbonate resin film, and is previously formed into a sheet-like spherical body. The molded body is manufactured by placing the polarizing composite sheet in a molding machine and injection-molding a polycarbonate resin forming a substrate at a molding temperature of 280 ° C.

In the methods described in JP-A-6-143339 and JP-A-2009-139964, the film can be formed along a curved surface such as irregularities, or can be processed along the shape of the end of the substrate. However, it is difficult to form a compact with limited use. If the molding temperature is too high to facilitate the molding and processing, the film may be colored. For example, coloring such as a colorless film turning brown also causes a narrow use of the molded body. In addition, the film described in JP-A-6-143339 may be deteriorated in antifogging properties when the molding temperature is too high. Furthermore, the molded body produced by the methods described in JP-A-6-143339 and JP-A-2009-139964 may impair transparency due to the occurrence of rainbow unevenness. Rainbow spots are multi-colored spots like a rainbow.

Therefore, an object of the present invention is to provide a method for producing a molded body that suppresses the occurrence of coloring and is excellent in transparency, workability, and moldability.

In order to achieve the above object, the method for producing a molded article of the present invention comprises a film material forming step and a molding step, and produces a molded article having a cellulose acylate film and a transparent substrate. In the film material forming step, a long film material is formed from cellulose acylate. In the molding step, the film material and the base material formed from the thermoplastic resin are integrally molded by thermoforming at a molding temperature within a range of 150 ° C. or higher and 240 ° C. or lower to obtain a molded body.

It is preferable to have a film material cutting step of cutting a long film material into a sheet shape between the film material forming step and the forming step.

Between the film material forming step and the molding step, the film material has a saponification step for forming a saponified layer containing saponified cellulose acylate, and the film material used for the molding step is an acyl group of the saponified layer. When the amount of acyl groups in the cellulose acylate layer formed from the cellulose acylate not saponified in the saponification step is Y and the amount of acyl groups determined by X / Y is 0.7, Preferably there is.

It is preferable to have a protective layer forming step for forming a protective layer for protecting the saponified layer on the surface of the saponified layer between the saponification step and the molding step.

In the forming step, it is preferable that the time from the start of heating of the film material to the end of forming be within a range of 30 seconds to 600 seconds.

The film material preferably has a thickness in the range of 15 μm to 100 μm.

When the glass transition point of cellulose acylate is defined as Tg, the molding temperature is preferably in the range of (Tg + 5 ° C.) to (Tg + 40 ° C.).

Between the film material forming step and the forming step, there is an adhesive layer forming step for forming an adhesive layer on the film surface of the film material, and the forming step is performed in such a state that the adhesive layer and the substrate material are in close contact with each other. It is preferable to integrally form the material and the base material.

The thermoplastic resin is preferably acrylic or polycarbonate.

According to the present invention, it is possible to obtain a molded article that suppresses the occurrence of coloring and is excellent in transparency, workability, and moldability.

It is explanatory drawing which shows the usage condition of a molded object. It is a section schematic diagram of a part of a forming object. It is a flowchart explaining the manufacturing method of a molded object. It is a section schematic diagram of a part of film material. It is a section schematic diagram of a forming device.

In FIG. 1, a cover as an example of the molded body 10 is used for, for example, a surveillance camera 100 that is required to be transparent, that is, a thing existing beyond the cover is visible. The surveillance camera 100 includes a camera body 102 having a photographing function, a support member 104 that supports the camera body 102, and a cover for covering the camera body 102, and this cover is the molded body 10. In this example, the molded body 10 has a dome shape.

As shown in FIG. 2, the molded body 10 includes a base material 11 as a molded body, an adhesive layer 12, and a cellulose acylate film 13. The thickness of the molded body 10 is not particularly limited and is, for example, in the range of 1 mm or more and 50 mm or less. From the viewpoint of further improving the transparency and strength of the molded body 10, it is more preferably in the range of 2 mm to 20 mm. In the present embodiment, the thickness of the molded body 10 is 2.1 mm, for example. The molded body 10 may not have the adhesive layer 12.

The base material 11 is transparent. The term “transparent” means that it has a light transmittance that can be photographed. The light here includes visible light (wavelength range of approximately 380 nm to 750 nm) and near infrared light (wavelength range of approximately 750 nm to 2500 nm).

The base material 11 is formed in a curved sheet shape, and has a dome shape in this embodiment. However, it is not limited to the sheet-like substrate 11 and may be a lens-like substrate. The shape of the substrate is not limited to the dome shape, and may be a desired shape. On at least one surface of the base material 11, an adhesive layer 12 for further suppressing the cellulose acylate film 13 from peeling from the base material 11 is provided. Although this base material 11 has a curved surface, in FIG. 2, the surface of the base material 11 is drawn on a plane for convenience of explanation. The thickness of the base material 11 is not specifically limited, For example, it shall be in the range of 1 mm or more and 50 mm or less. From the viewpoint of further improving the transparency as the substrate 11 and the moldability to a desired shape, the thickness of the substrate 11 is more preferably in the range of 2 mm or more and 20 mm or less. In this embodiment, the thickness of the base material 11 is 2 mm, for example.

The cellulose acylate film 13 is made of cellulose acylate. The cellulose acylate is cellulose triacetate (triacetyl cellulose, hereinafter referred to as TAC) in the present embodiment, but is not limited to TAC, and may be other cellulose acylate different from TAC. By using cellulose acylate, rainbow unevenness is suppressed, and as a result, transparency is ensured. Rainbow spot is a light interference phenomenon caused by reflection of light on the film surface and refraction of incident light on each film surface when irradiated with light. The cellulose acylate film 13 is provided on the base material 11 through the adhesive layer 12. That is, the cellulose acylate film 13 is provided on the surface of the adhesive layer 12 opposite to the substrate 11.

The cellulose acylate film 13 has a two-layer structure having a saponified layer 14 and a cellulose acylate layer 15, and the cellulose acylate layer 15 is arranged in a state where it is on the substrate 11 side, that is, the adhesive layer 12 side. ing.

The saponification layer 14 is for imparting antifogging properties to the cellulose acylate film 13. Therefore, when the anti-fogging function is unnecessary, the saponified layer 14 may not be provided. Antifogging properties include initial antifogging properties and long-term antifogging properties. The initial anti-fogging property is a function that prevents instantaneous condensation. Long-term antifogging is a function that prevents condensation for a long time. In this embodiment, the saponification layer 14 bears both functions of initial antifogging property and long-term antifogging property. The saponified layer 14 comprises saponified cellulose acylate, in this example saponified TAC.

The cellulose acylate layer 15 is made of cellulose acylate, in this example, TAC. The cellulose acylate layer 15 does not contain saponified cellulose acylate.

As shown in FIG. 3, the molded body 10 includes a first material forming step 31 for forming a film material 20 as a first material, and a base material 22 as a film material 20 and a second material. It is manufactured by a molding step 32 which is integrally formed by thermoforming.

The first material forming step 31 includes a film material forming step 33, a saponification step 34, a protective layer forming step 35, an adhesive layer forming step 36, and a film material cutting step 37. The 1st raw material obtained through the process is the film material 20 (refer FIG. 4).

The film material forming step 33 is a step of forming a long film material from cellulose acylate. This film material is referred to as a first intermediate. In the saponification step 34, a saponified layer containing saponified cellulose acylate is formed on the first intermediate. In the protective layer forming step 35, a protective layer for protecting the saponified layer is formed on the surface of the saponified layer. In the adhesive layer forming step 36, an adhesive layer is formed on the film surface of the film material. The details of the saponification layer, the protective layer, and the adhesive layer will be described later with reference to another drawing.

The thermoforming method in the forming step 32 is any one of vacuum / pressure forming, vacuum forming, pressure forming, film insert forming, and in-mold forming, and in this embodiment, vacuum / pressure forming. The integral molding means that a product (molded body) is molded integrally with the joining of the members based on Japanese Industrial Standard JIS K-7010.

A method for manufacturing the molded body 10 by the above steps will be described below. The first material forming step 31 will be described with reference to FIGS. 3 and 4. In the film material forming step 33, a film material which is a first intermediate is formed by a solution casting method in this example. Specifically, it is produced by casting a polymer solution containing TAC as cellulose acylate (hereinafter referred to as a dope) to a support to form a cast film, peeling the cast film from the support and drying it. Is done. The glass transition point Tg of the cellulose acylate used in the film material forming step 33 is preferably in the range of 150 ° C. or higher and 180 ° C. or lower.

Details of the cellulose acylate will be described below. Cellulose acylate has a ratio in which the hydroxy group of cellulose is esterified with carboxylic acid, that is, the substitution degree of acyl group (hereinafter referred to as acyl substitution degree) satisfies all the conditions of the following formulas (1) to (3). What is satisfactory is particularly preferred. In (1) to (3), A and B are both acyl group substitution degrees, the acyl group in A is an acetyl group, and the acyl group in B has 3 to 22 carbon atoms.
2.0 ≦ A + B ≦ 3.0 (1)
0 ≦ A ≦ 3.0 (2)
0 ≦ B ≦ 2.9 (3)

The glucose unit constituting cellulose and having β-1,4 bonds has hydroxy groups at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer in which some or all of the hydroxy groups of cellulose are esterified, and the hydrogen of the hydroxy group is substituted with an acyl group having 2 or more carbon atoms. In addition, since the substitution degree is 1 when esterification of one hydroxy group in the glucose unit is 100%, in the case of cellulose acylate, the hydroxy groups at the 2nd, 3rd and 6th positions are 100 respectively. When% esterified, the degree of substitution is 3.

Here, the total acyl group substitution degree obtained by “DS2 + DS3 + DS6”, where the acyl group substitution degree at the 2-position in the glucose unit is DS2, the acyl substitution degree at the 3-position is DS3, and the acyl substitution degree at the 6-position is DS6 is 2. It is preferably 00 to 2.97, and 2.86 in this embodiment.

There may be only one kind of acyl group or two or more kinds. When there are two or more acyl groups, it is preferable that one of them is an acetyl group. DSA is the sum of the substitution degrees of the hydrogen groups of the hydroxy groups at the 2nd, 3rd and 6th positions with the acetyl group, and DSB is the sum of the substitution degrees with the acyl groups other than the acetyl groups at the 2nd, 3rd and 6th positions. In this case, the value of “DSA + DSB” is preferably 2.20 to 2.86, and particularly preferably 2.40 to 2.80. DSB is preferably 1.50 or more, and particularly preferably 1.7 or more. In DSB, 28% or more is preferably 6-position hydroxy group substitution, more preferably 30% or more, further preferably 31% or more, particularly preferably 32% or more substitution of 6-position hydroxy group. It is preferable that In addition, the value of “DSA + DSB” at the 6-position of cellulose acylate is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more.

The acyl group having 2 or more carbon atoms may be an aliphatic group or an aryl group, and is not particularly limited. For example, there are alkyl carbonyl ester, alkenyl carbonyl ester, aromatic carbonyl ester, and aromatic alkyl carbonyl ester of cellulose, and these may each further have a substituted group. Propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t-butanoyl group, cyclohexane Examples thereof include a carbonyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, and a cinnamoyl group. Among these, a propionyl group, a butanoyl group, a dodecanoyl group, an octadecanoyl group, a t-butanoyl group, an oleoyl group, a benzoyl group, a naphthylcarbonyl group, a cinnamoyl group, and the like are more preferable, and a propionyl group and a butanoyl group are particularly preferable.

The saponification process 34 manufactures the film base 23 as a 2nd intermediate body by performing a saponification process to a 1st intermediate body. In this embodiment, it manufactures by apply | coating the alkaline solution as a saponification liquid to one film surface of the film material as a 1st intermediate body, heating the apply | coated film material, and wash | cleaning with water. It is preferable to contain isopropyl alcohol in the saponification solution, and this is the case in this embodiment. In the film base 23, the cellulose acylate is saponified by the saponification treatment, and a region formed in a layer form is the saponified layer 24. That is, the saponification step 34 is a step of forming a saponification layer 24 containing saponified cellulose acylate on a film material. The saponification layer 24 forms one base surface (hereinafter referred to as a first base surface) 23 a of the film base 23. This saponified layer 24 becomes the saponified layer 14 of the molded body 10.

The cellulose acylate layer 25 is a non-saponified portion that has not been saponified in the film base 23, that is, the remainder excluding the saponified layer 24. Therefore, the cellulose acylate layer 25 is formed from cellulose acylate that has not been saponified in the saponification step 34. The cellulose acylate layer 25 forms the other base surface (hereinafter referred to as a second base surface) 23 b of the film base 23. The cellulose acylate layer 25 becomes the cellulose acylate layer 15 of the molded body 10.

In addition, although the saponification layer 24 has comprised the 1st base surface 23a, the film base 23 is not restricted to this. That is, the saponification layer 24 may be provided so as to form a second base surface in addition to the first base surface 23a.

The thickness of the film base 23 (the sum of the thickness of the cellulose acylate layer 25 (see FIG. 4) and the thickness of the saponified layer 24 (see FIG. 4)) T23 is preferably in the range of 15 μm to 100 μm. As will be described later, a film material that does not have at least one of the saponified layer 24 and the protective layer 26 (see FIG. 4) may be used as the first material. In this case, it is preferable that the thickness of the first material to be used is regarded as T23 described above and is in the range of 15 μm to 100 μm. When the thickness T23 is 15 μm or more, generation of tears and wrinkles during molding is suppressed as compared with the case where the thickness T23 is less than 15 μm, and when the thickness T23 is 100 μm or less, the thickness T23 is larger than 100 μm. Along with the shape of the base material 22 having a curved surface such as a dome shape and unevenness (hereinafter referred to as moldability) and the shape of the end of the sheet-like or flat base material. This is because it is more excellent in ease of processing (hereinafter referred to as processability). The thickness T23 is more preferably in the range of 18 μm or more and 60 μm or less, and further preferably in the range of 20 μm or more and 50 μm or less. In the present embodiment, the thickness T23 is set to 40 μm, for example.

The thickness T23 has a correlation with the moisture permeability of the film material 20. Specifically, the smaller the thickness T23, the higher the moisture permeability, that is, the better the moisture permeability of the film material 20. The outgas is considered that the moisture contained in the base material 22 and / or the adhesive layer 27 is evaporated, and the film material 20 having moisture permeability transmits the outgas. Based on the Japanese Industrial Standard JIS Z-0208, when the moisture permeability is evaluated at 40 ° C. and 90% RH (relative humidity), the moisture permeability of the film material 20 is 550 g / (m ² · 24 h) or more. Is preferred. Even if outgas is generated, in the molded body 10, since the outgas passes through the cellulose acylate film 13 and is released to the outside, the occurrence of the bubbles and / or peeling is suppressed. Therefore, it is preferable from the viewpoint of moisture permeability that the thickness T23 is within the above range. Furthermore, since the film material 20 is formed of cellulose acylate, the film material 20 is superior in moisture permeability as compared with a case where it is formed of polyethylene terephthalate (hereinafter referred to as PET). Since the film material 20 having excellent moisture permeability as described above is neatly bonded to the base material 22, the design of the molded body 10 is improved. Furthermore, since the stuck state is maintained over a long period of time, the durability of the molded body 10 is improved.

When the amount of acyl groups in the saponified layer 24 is X and the amount of acyl groups in the cellulose acylate layer 25 is Y, the ratio of acyl groups determined by X / Y (hereinafter referred to as the acyl group ratio) is 0. 0.7, that is, 0.7 or less, and in this embodiment, for example, 0.3. The smaller the acyl group ratio, the fewer the acyl groups of the saponified layer 24 relative to the cellulose acylate layer 25, which means that more acyl groups were saponified in the saponification treatment, resulting in hydrophilic groups.

The acyl group ratio is related to the initial antifogging property. Specifically, the smaller the acyl group ratio, the better the initial antifogging property. When the acyl group ratio is 0.7 or less, that is, in the range of 0 or more and 0.7 or less, a superior initial antifogging property is exhibited as compared with a case where the ratio is larger than 0.7. The acyl group ratio is more preferably in the range of 0.01 to 0.6, and still more preferably in the range of 0.05 to 0.5.

The acyl group amount X and the acyl group amount Y are the total reflection measurement (ATR, Attenuated Total Reflection) method (hereinafter, referred to as FT-IR, Fourier Transform Infrared Spectroscopy, hereinafter referred to as FT-IR). This is determined as the spectral intensity of the acyl group determined by the ATR method. Specifically, the spectral intensity of the acyl group signal of the cellulose acylate is corrected (normalized) with the spectral intensity of the common signal of the cellulose polymer. In this embodiment, since TAC is used as the cellulose acylate, the acyl group is an acetyl group, and the signal of the acetyl group is 1210 cm ⁻¹ . The common signal of the cellulosic polymer is preferably 1030 cm ⁻¹ . Then, the spectrum intensity of the acyl group signal of the cellulose acylate obtained by the correction is determined as an acyl group amount X or an acyl group amount Y, respectively. Thus, the acyl group amount X and the acyl group amount Y are indices that are replaced by the number of acyl groups.

As is well known, the FT-IR ATR method is a method for obtaining a spectral intensity by allowing light to enter a measurement sample, and the obtained spectral intensity is not the surface of the measurement sample in the strict sense. . When a diamond prism is used as a method in a general FT-IR ATR method and the measurement angle is 45 degrees, the light penetration depth from the surface of the measurement sample is about 2 to 3 μm. It is. Since the saponification layer 24 of the present embodiment is very thin as will be described later, the reliability as the amount of acyl groups required for the saponification layer 24 decreases as the light penetration depth becomes deeper than 2 μm. Therefore, it is preferable to obtain the spectrum intensity in the range of 2 μm depth from the first base surface 23a of the film base 23 as the acyl group amount X. In this embodiment, the light penetration depth is set to 2 μm, and the first The spectrum intensity in the range of 2 μm or less from the base surface 23a is defined as the acyl group amount X.

Similarly, it is preferable to obtain the spectrum intensity in the range of 2 μm in depth from the second base surface 23b of the film base 23 as the acyl group amount Y, and this is also the case in this embodiment. When the saponification layer 24 has not only the first base surface 23a but also the second base surface, that is, a saponification layer is provided on both surfaces of the film base, and a cellulose acylate layer is provided between the saponification layers. Is provided, the amount of acyl group is determined at the center in the thickness direction of the film base, and this is used as the amount of acyl group Y. From the viewpoint of simplicity and reliability as the amount of acyl group required for the film base From the viewpoint of sex. When it is difficult to determine the acyl group amount Y on the second base surface by the above method, the film base is dissolved in methylene chloride and / or chloroform, and a film is formed from this solution. The amount of acyl group on the film surface may be determined by other methods such as IR (infrared absorption spectroscopy).

Long-term antifogging is related to the contact angle after 15 seconds. The contact angle after 15 seconds is a characteristic indicating that the hydrophilic component is sufficiently present on the first base surface 23 a of the film base 23. As described above, when the first base surface 23a has a large amount of hydrophilic components, the water droplets condensed on the first base surface 23a can be maintained in a sufficiently wet and spread state, which is effective for long-term antifogging properties. Conceivable. When the contact angle after 15 seconds is 35 ° or less, the anti-fogging property tends to be particularly good. The first base surface 23a has a contact angle of 35 ° or less after 15 seconds, and is, for example, 25 ° in this embodiment. The contact angle after 15 seconds is related to the long-term antifogging property, but in order to make the contact angle after 15 seconds 35 ° or less, the saponification treatment conditions are adjusted, and the acyl group ratio becomes 0.7 or less. As described above, by controlling the acyl group amount X of the first base surface 23a, the plasticizer and / or additive in the cellulose acylate depending on the temperature and / or time of the thermoforming process is ensured by sufficiently securing the thickness of the saponified layer. Plasticity by controlling the diffusion and / or migration of the saponification layer to the surface, adjusting the type of plasticizer and / or additive, and increasing the molecular weight of the plasticizer and / or additive in cellulose acylate Suppressing diffusion and / or migration of agents and / or additives to the surface of the saponification layer, and suppressing increase in contact angle due to migration components from the laminate film by selecting a laminate film to be described later There is. The contact angle after 15 seconds is preferably 30 ° or less, more preferably 25 ° or less, and further preferably 20 ° or less. The contact angle is obtained in consideration of the time after the pure water is dropped, and the contact angle after 15 seconds, which is 15 seconds later, is used to obtain a film base 23 with excellent long-term antifogging properties. It is done. The contact angle after 15 seconds is a characteristic showing the affinity of the film surface with water. In the measurement of the contact angle with respect to water, pure water permeates into a hydrophilic portion (hereinafter referred to as a hydrophilic film) formed in a film shape with a very small thickness on the surface of the saponified layer 24, or a hydrophilic film. The phenomenon of film components coming out from the inside occurs with the passage of time after the addition of pure water, but measuring the hydrophilicity corresponding to the long-term antifogging property of the film surface by making the measurement 15 seconds after dropping. I found out that I can do it.

The contact angle after 15 seconds is preferably measured with respect to the film base 23 after humidity adjustment (humidity adjustment). The humidity treatment conditions are a temperature range of 23 ° C. to 28 ° C., and a relative humidity of The atmosphere is preferably in the range of 55% to 65%, and the humidity adjustment time is more preferably 1 hour or more. In this embodiment, the humidity is adjusted for 1 hour in an atmosphere having a temperature of 25 ° C. and a relative humidity of 60%. In this humidity conditioning treatment, the entire film base 23 may be humidity-conditioned, but at least the saponified layer 24 may be conditioned.

Further, by setting the thickness T24 of the saponified layer 24 within a predetermined range, it is possible to more surely satisfy both the initial antifogging property and the long-term antifogging property. Specifically, it is as follows. There is a correlation between the acyl group ratio and the thickness T24, and the thickness T24 increases as the acyl group ratio decreases. As described above, the initial antifogging property is better as the acyl group ratio is smaller, and as the thickness T24 is larger, it is better.

Further, as the thickness T24 of the saponified layer 24 increases from 0 (zero), the contact angle gradually decreases after 15 seconds, but gradually increases when the thickness T24 increases to some extent. As the reason for this gradual increase, the following (1) or (2) can be considered. That is, (1) when the saponification conditions described later are increased in order to increase the thickness T24, the aforementioned hydrophilic film that reduces the contact angle after 15 seconds decreases, and (2) the thickness T24 increases. If it is too much, the holding area where water can be held becomes too large, and as a result, the water enters the inside of the first base surface 23a. Since the long-term antifogging property is manifested when the contact angle after 15 seconds is 35 ° or less as described above, the long-term antifogging property corresponds to 35 ° in the gradually increasing region of the contact angle after 15 seconds. The thickness T24 is preferably set with the thickness as the upper limit. Thereby, in addition to initial antifogging property, long-term antifogging property is ensured more reliably.

From the above, the thickness T24 is preferably in the range of 1 μm or more and 6 μm or less in order to express the initial antifogging property and the long-term antifogging property more reliably. In the present embodiment, the thickness T24 is in the range of 2 μm or more and 5 μm. It is within. That is, when the thickness T24 is 1 μm or more, the initial antifogging property is more reliable than when it is less than 1 μm, and when it is 6 μm or less, the long-term antifogging property is more than when it is larger than 6 μm. Be certain.

In addition, thickness T24 is calculated | required with the following method in this embodiment. A sample sampled from the film base 23 is immersed in dichloromethane for 24 hours. The sample which remained undissolved by this immersion was dried, and the thickness of the dried sample was measured three times. The average of the three measured values is defined as thickness T24.

In the film base 23, the amount of C═O (carboxyl group) of the acyl group bonded to the hydroxyl group component of cellulose in the range of 2 μm in depth from the first base surface 23a is the hydroxyl group component of cellulose on the second base surface 23b. It is preferably 70% or less with respect to the amount of C═O of the acyl group bonded to, and in the present embodiment, it is in the range of 30% to 70%. For example, when the acyl group ratio cannot be obtained, the contact angle is set to 20 ° or less after 15 seconds, and the amount of C═O of the acyl group bonded to the hydroxyl group component of the cellulose group on the second base surface 23b is determined. Even if the amount of C═O of the acyl group bonded to the hydroxyl group component of the cellulose group having a depth in the range of 2 μm from the first base surface 23a is 70% or less, the initial antifogging property and the long-term antifogging property are To express.

The cellulose acylate forming the film base 23 preferably contains an ester oligomer or an ester derivative of sugar. By including these, the processability and moldability of cellulose acylate can be improved, and the diffusion and / or migration of the additive to the surface of the saponified layer can be suppressed. When the ester oligomer or sugar ester derivative is contained in cellulose acylate, the dope used in the film material forming step 33 is preferably made of cellulose acylate containing the ester oligomer or sugar ester derivative. These ester oligomers and ester derivatives of sugar function as plasticizers. The glass transition point of cellulose acylate containing ester oligomer or sugar ester derivative is smaller than the glass transition point of cellulose acylate not containing ester oligomer or sugar ester derivative. It is effective as a plasticizer when molding by thermoforming. Of the ester oligomer and the ester derivative of sugar, the ester oligomer is more preferable as the plasticizer. More specifically, it is preferable that an ester oligomer having a molecular weight in the range of 400 or more and 10,000 or less is included as a plasticizer, and the film base 23 of the present embodiment also includes this. Since the ester oligomer has a molecular weight distribution unlike the above-described plasticizer having a molecular weight of less than 400, the molecular weight of the ester oligomer is determined by GPC (Gel Permeation Chromatography), weight average molecular weight or number average molecular weight, terminal functionality. It can be determined by a number average molecular weight measurement method based on measurement of base weight or osmotic pressure, a viscosity average molecular weight based on viscosity measurement, and the like. In this embodiment, the hydroxyl group or acid group of the ester is measured as the terminal functional group, and the molecular weight of the ester oligomer is determined by the number average molecular weight measurement method using this. By using an ester oligomer having a molecular weight in the range of 400 or more and 10,000 or less as a plasticizer, the film base 23 can be attached and / or easily applied to the base material 22 that is an object to be attached. The so-called handleability such as ease of re-sticking is reliably improved. Further, by using the above ester oligomer as a plasticizer, precipitation on the first base surface 23a is more reliably suppressed as compared with the case of using a general plasticizer monomer having a molecular weight of less than 400, and Since the contact angle after 15 seconds on the first base surface 23a tends to be small, the long-term antifogging property is more reliably exhibited. The longer the molecular weight of the SL oligomer, the better the long-term antifogging property, and the smaller the molecular weight, the better the compatibility with the cellulose acylate. Therefore, the molecular weight of the ester oligomer is more preferably in the range of 700 to 5000, more preferably 900 to 3000. It is further preferable to be within the range.

Furthermore, the ester oligomer used as a plasticizer is a compound having a relatively low molecular weight having a repeating unit containing an ester bond of a dicarboxylic acid and a diol, and having a repeating unit in the range of 2 to 100. An ester oligomer is preferred. This is because the action of cellulose acylate as a plasticizer is more reliable.

The above dicarboxylic acid is more preferably an aliphatic dicarboxylic acid having a carbon number in the range of 2 to 10. The diol is more preferably an aliphatic diol having 2 to 10 carbon atoms. This is because by using an aliphatic dicarboxylic acid and an aliphatic diol, flexibility can be imparted to the film base 23, and it is difficult to generate degradation products that inhibit the reduction of the contact angle after 15 seconds described later. is there. Examples of the aliphatic carboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, cyclohexanedicarboxylic acid, maleic acid, fumaric acid and the like. Aliphatic diols include ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1, 4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 1,4-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedi Methanol etc. are mentioned. It is also preferable to seal the terminal hydroxyl group and / or acid group of the ester oligomer with a monocarboxylic acid or monoalcohol. Among these, an oligomer having an ester of adipic acid and ethylene glycol as a repeating unit, an oligomer having an ester of succinic acid and ethylene glycol as a repeating unit, an ester of terephthalic acid and ethylene glycol, and an ester of phthalic acid and ethylene glycol Oligomers having an ester as a repeating unit are preferred. In this embodiment, an ester oligomer composed of adipic acid and ethanediol (the number average molecular weight determined by the terminal hydroxyl group determination method is about 1000) is used as the ester.

The mass of the ester oligomer is preferably 30% at most, that is, 30% or less with respect to the mass of the cellulose acylate. That is, when the mass of the cellulose acylate in the film base 23 (including the saponified cellulose acylate in the saponified layer 24) is MA and the mass of the ester oligomer in the film base 23 is MB, the film base 23 is ( The mass ratio (unit:%) determined by (MB / MA) × 100 is 30% or less. When this mass ratio is 30% or less, the precipitation of the ester oligomer is suppressed as compared with the case where it is larger than 30%, and the white turbidity due to the precipitation of the ester oligomer can be suppressed even during the heat molding, and It can suppress that the contact angle of the saponification layer 14 as the molded object 10 becomes large. The mass ratio in the cellulose acylate film 13 is more preferably 4% or more and 30% or less, and further preferably 10% or more and 25% or less.

Details of the ester derivatives of sugar will be described below. The sugar ester derivative may be either a monosaccharide ester derivative or a polysaccharide ester derivative. The film base 23 may include both of these.

The monocarboxylic acid used for esterifying all or part of the OH groups in the monosaccharide and polysaccharide structures is not particularly limited, and is a known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, An aromatic monocarboxylic acid or the like can be used. The carboxylic acid used may be one kind or a mixture of two or more kinds.

Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, undecylic acid, lauric acid , Saturated fatty acids such as tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melicic acid, and laccelic acid, Undecylenic acid, oleic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, octenoic acid and other unsaturated fatty acids, cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, cyclooctanecarboxylic acid, and other alicyclic monocarboxylic acids, etc. Can be mentioned. Examples of the sugar include monosaccharides such as glucose, galactose, mannose, fructose, xylose, arabinose, lactose, sucrose, nystose, 1F-fructosyl nystose, stachyose, maltitol, lactitol, lactulose, cellobiose, maltose, cellotriose, maltotriose Examples include polysaccharides such as oose, raffinose or kestose, gentiobiose, gentiotriose, gentiotetraose, xylotriose, galactosyl sucrose. Glucose, fructose, sucrose, kestose, nystose, 1F-fructosyl nystose, stachyose and the like are preferable, and sucrose and glucose are more preferable. Oligosaccharides can also be used as polysaccharides, which are produced by causing an enzyme such as amylase to act on starch, sucrose, etc. Examples of oligosaccharides include malto-oligosaccharides, iso-saccharides, and the like. Examples include maltooligosaccharide, fructooligosaccharide, galactooligosaccharide, and xylo-oligosaccharide.

Examples of preferred aromatic monocarboxylic acids include aromatic monocarboxylic acids having an alkyl group or alkoxy group introduced into the benzene ring of benzoic acid such as benzoic acid and toluic acid, cinnamic acid, benzylic acid, biphenylcarboxylic acid, and naphthalene. Examples thereof include aromatic monocarboxylic acids having two or more benzene rings such as carboxylic acid and tetralincarboxylic acid, or derivatives thereof, and benzoic acid and naphthylic acid are particularly preferable.

The mass of the sugar ester derivative is preferably at most 15%, that is, 15% or less with respect to the mass of the cellulose acylate. That is, when the mass of the cellulose acylate in the film base 23 (including the saponified cellulose acylate in the saponified layer 24) is MA and the mass of the sugar ester derivative in the film base 23 is MC, the film base 23 is , (MC / MA) × 100, the mass ratio (unit:%) obtained is 15% or less. When the mass ratio is 15% or less, the precipitation of the sugar ester derivative can be suppressed as compared with the case where the mass ratio is larger than 15%, and the white turbidity due to the precipitation of the sugar ester derivative can be suppressed even during heat molding. And the increase in the contact angle of the saponified layer 14 as the molded body 10 can be suppressed. The mass ratio in the cellulose acylate film 13 is more preferably 4% or more and 15% or less, and further preferably 6% or more and 15% or less.

In addition to cellulose acylate and the above plasticizer, the film base 23 includes various additives such as an ultraviolet absorber and a deterioration preventing agent, and / or fine particles for preventing the film bases 23 from sticking to each other, for example. It may be.

The protective layer forming step 35 is a step of forming a protective layer 26 that protects the saponified layer 24 on the surface of the saponified layer 24 of the film base 23. In this embodiment, the protective layer 26 is formed by superposing a commercially available laminate film on the saponified layer 24. The film material having the protective layer 26 is referred to as a third intermediate. The protective layer 26 is affixed until the molded body 10 is used, and is removed when the molded body 10 is used. For this reason, the protective layer 26 prevents the saponification layer 24 from being contaminated and / or damaged during molding. The protective layer 26 protects the saponified layer 14 exposed as an outer surface during use from contamination and / or damage during storage and / or transportation of the molded body 10, that is, protects the molded body 10 before use. It also has a function to do. The laminate film used as the protective layer 26 is a commercially available laminate film from the viewpoint of heat resistance in thermoforming, suppressing the increase in contact angle due to the transfer from the laminate film during thermoforming and / or storage, and the like. Can be selected as appropriate. As the laminate film, a film formed of polyethylene or polypropylene can be used, and examples thereof include a polyolefin-based film and a polyethylene terephthalate film. Among these, in the thermoforming process of the present invention, a polyethylene terephthalate film is more preferable from the viewpoint of heat resistance. Moreover, the laminate film which suppresses the raise of the contact angle of the saponification layer 24 is the saponification as a molded object obtained by heat-molding the contact angle of the saponification layer before heat-molding, and bonding a commercial item to the saponification layer. The contact angle of the layers can be selected as appropriate by comparing the contact angle and confirming the change. As such a commercially available laminate film, LG Chemical's laminate film LDM-EPDC (50μ) and Sumilon Laminated film EC7501 (polyolefin) is available. In the present embodiment, the former laminate film is used.

The adhesive layer forming step 36 is a step of forming the adhesive layer 27 on the film surface of the third intermediate. This adhesive layer 27 becomes the adhesive layer 12 of the molded body 10. The adhesive layer 27 is more closely attached to the base material 22 in the molding step 32, thereby further improving the difficulty of peeling the cellulose acylate film 13 from the base material 11 in the molded body 10. In the present embodiment, the adhesive layer 27 is formed by providing a commercially available adhesive or pressure-sensitive adhesive on the surface on the cellulose acylate layer 25 side of the film material as the third intermediate. The film material having the adhesive layer 27 is referred to as a fourth intermediate.

Since the adhesive layer 27 is for suppressing the peeling between the cellulose acylate film 13 and the substrate 11, it is formed by using a heat-resistant adhesive or pressure-sensitive adhesive that can withstand heating in thermoforming. It is preferable. The adhesive layer 27 is preferably formed of any one of vinyl acetate resin, epoxy resin, vinyl chloride resin, hot melt adhesive, acrylic pressure-sensitive adhesive, silicone pressure-sensitive adhesive, and rubber-based pressure-sensitive adhesive. Among them, an acrylic adhesive or a silicone adhesive is more preferable, and an acrylic adhesive is used in the present embodiment. In this specification, “adhesion” means that the objects to be attached are attached in an integrated state, and “adhesion” is a kind of adhesion, and after being attached to an adherend. It means that the change in the sticking force (adhesive force) is small even after a certain period of time and can be peeled off if necessary. In the present invention, it is preferable to use an adhesive or pressure-sensitive adhesive having a usable temperature, that is, a heat resistant temperature of 150 ° C. or higher. This usable temperature can be selected depending on the temperature at the time of adhesion processing depending on the presence or absence of adhesiveness or tackiness, smoothness, coloring, foaming (bubbles) and the like. The adhesiveness means, for example, the degree of adhesive force between objects to be attached. Adhesive means, for example, the degree of adhesive strength. Smoothness means, for example, the degree of unevenness on the surface. Here, the adhesive or the pressure-sensitive adhesive preferably has a heat resistant temperature in the range of 150 ° C. or higher and 250 ° C. or lower. In this embodiment, the heat resistant temperature is 220 ° C. When the heat resistant temperature is 150 ° C. or higher, coloring and / or foaming of the adhesive layer 27 at the time of molding can be suppressed as compared with the case where the heat resistant temperature is lower than 150 ° C., and the heat resistant temperature is 250 ° C. or lower. As compared with the case where the temperature is higher than 250 ° C., various durability of the adhesive performance (or adhesive performance) as a molded body (peeling and clouding in a high temperature and high humidity and / or time environment), cellulose of the molded body 10 The removability when the acylate film 13 is replaced is good. The heat resistant temperature is more preferably in the range of 160 ° C. or higher and 240 ° C. or lower, and further preferably in the range of 180 ° C. or higher and 230 ° C. or lower. In addition to the strength of the adhesive layer 27, the adhesive or pressure-sensitive adhesive is appropriately selected from the viewpoints of durability in a high-temperature and high-humidity environment after adhesion or adhesion, white turbidity, outgas, transparency of the molded body, and the like. be able to.

In the present embodiment, a commercially available adhesive, for example, an acrylic adhesive sheet manufactured by Soken Chemical Co., Ltd. is used. In addition, 3M Co., Ltd. silicone baseless double-sided tape 91022, Nichiei Kako Co., Ltd. optical baseless double-sided tape MHM, and Mitsubishi Rayon Co., Ltd. Dianal (registered trademark), Toa Gosei Co., Ltd. Aron, Sumitomo Chemical Co., Ltd. Sumipex (registered trademark), etc. may be used.

The thickness T27 of the adhesive layer 27 is preferably in the range of 1 μm to 50 μm, and in this embodiment, the thickness of the adhesive layer 27 is set to 15 μm, for example. Compared to the case where the thickness T27 is 1 μm or more, compared to the case where the thickness T27 is less than 1 μm, the adhesive force or adhesive strength after heat molding is excellent. Foaming of the adhesive or pressure-sensitive adhesive during heat molding is suppressed, and further, coloring of the molded body itself is suppressed by suppressing coloring of the adhesive or pressure-sensitive adhesive. The thickness T27 is more preferably in the range of 3 μm to 40 μm, and still more preferably in the range of 5 μm to 30 μm.

The film material cutting step 37 is a step of cutting a long film material into a sheet shape. In this embodiment, since the 4th intermediate body is made into the elongate film material, the film material 20 is manufactured by cutting into the sheet form of a desired magnitude | size. Therefore, the film material 20 is formed in a sheet shape, and has a saponified layer 24, a cellulose acylate layer 25, a protective layer 26, and an adhesive layer 27.

In the present embodiment, the first material forming step 31 includes a film material forming step 33, a saponification step 34, a protective layer forming step 35, an adhesive layer forming step 36, and a film material cutting step 37. However, there is a case where at least the film material forming step 33 is performed and at least one of the other steps is not performed. When the saponification step 34 is not performed, the film material does not have the saponification layer 24. When the protective layer forming step 35 is not performed, the protective layer 26 is not present in the film material. When the adhesive layer forming step 36 is not performed, the adhesive layer 27 does not exist in the film material. When not performing the film material cutting process 37, a film material is long. As described above, each of the first intermediate body, the second intermediate body, the third intermediate body, and the fourth intermediate body can be provided to the forming step 32 as a film material.

The second material is formed from a thermoplastic resin by the second material forming step. The thermoplastic resin is preferably polycarbonate (hereinafter referred to as PC) or acrylic. In this embodiment, acrylic is used. PC or acrylic is used because it has high transparency, is lighter and more durable than glass, and can be easily formed into a desired shape. The PC as the second material preferably has a glass transition point of 150 ° C. The acrylic as the second material preferably has a glass transition point of 100 ° C.

The second material is different in the form used for the molding apparatus 50 described later according to the thermoforming technique. In the case of vacuum pressure forming, vacuum forming, and pressure forming, for example, injection molding is performed in the second material forming step, the thermoplastic resin forming the base material 11 is melted, and this molten resin is filled in a mold. The molded product formed into a desired shape by cooling and solidifying is the second material. In the present embodiment, the base material 22 formed in a dome shape is used as the second material. Further, in the second material forming step, for example, a thin sheet material may be manufactured by a solution casting method, and this may be used as the second material. On the other hand, in the case of film insert molding and in-mold molding, as the second material forming step, the thermoplastic resin forming the base material 11 is melted, and this molten resin is the second material.

The forming step 32 is performed using, for example, a forming apparatus 50 shown in FIG. The forming apparatus 50 forms the formed body 10 by integrally forming the film material 20 and the base material 22 by thermoforming.

The molding device 50 includes a chamber 51, a heater 52, a table 53, a moving mechanism 54, a vacuum pump 55, a compressor 56, and a control unit 57, and is a device for performing vacuum / pressure forming as thermoforming. is there. In the present embodiment, the base material 22 having a dome shape is provided to the molding apparatus 50, but in FIG. 5, the base material 22 is drawn in a flat plate shape for convenience of explanation. Further, in FIG. 5, the thickness of the film material 20 is exaggerated for easy understanding of each layer of the film material 20. In this embodiment, a commercially available device such as a TOM (Three （dimension Overlay Method) molding machine (trade name; NGF (Next Generation Forming) molding machine) manufactured by Fuse Vacuum Co., Ltd. is used as the molding device 50.

The chamber 51 includes an upper chamber 51a and a lower chamber 51b, and the upper chamber 51a is movable in the vertical direction in FIG. 5, that is, in the direction of increasing or decreasing the distance between the upper chamber 51a and the lower chamber 51b. ing. By lowering the upper chamber 51a and bringing the upper chamber 51a and the lower chamber 51b into close contact with each other, the inside of the chamber 51 is brought into an airtight state. The upper chamber 51 a is provided with a heater 52 for heating the film material 20. The lower chamber 51b is provided with a table 53 on which the base material 22 is placed.

The heater 52 emits, for example, far-infrared rays (wavelength range of approximately 4 μm or more and 1000 μm or less) when it operates to heat the film material 20. The table 53 is movable in the vertical direction in FIG. 5 with respect to the lower chamber 51b. The moving mechanism 54 moves the upper chamber 51a and the table 53 in the vertical direction in FIG. The vacuum pump 55 is connected to an exhaust hole 58 provided in the upper chamber 51a and an exhaust hole 59 provided in the lower chamber 51b. The vacuum pump 55 exhausts air from the exhaust holes 58 and 59 when the inside of the chamber 51 is in an airtight state, and makes the inside of the chamber 51 in a vacuum state. The compressor 56 is connected to an exhaust hole 58 provided in the upper chamber 51a, and the compressed air is jetted into the upper chamber 51a through the exhaust hole 58. These moving mechanism 54, heater 52, vacuum pump 55, and compressor 56 are controlled by a control unit 57.

The molding device 50 is provided with a thermometer (not shown) for measuring the temperature of the film material 20, and the control unit 57 controls the amount of heat generated by the heater 52 based on the temperature of the thermometer. As the thermometer, for example, a non-contact thermometer that measures the surface temperature of the film material 20 in a non-contact manner is used.

Further, the control unit 57 has a timer function, and controls the time (hereinafter referred to as molding time) from the start of heating the film material 20 to the end of molding. In this embodiment, “start heating” means when the heater 52 is activated. In this embodiment, “the molding is completed” means that the upper chamber 51a and the lower chamber 51b are brought to atmospheric pressure by the compressor 56 after the film material 20 is molded and bonded to the base material 22. Means when

A procedure for manufacturing the molded body 10 using the molding apparatus 50 will be described. The film material 20 is set between the upper chamber 51a and the lower chamber 51b with the adhesive layer 27 facing the lower chamber 51b.

Next, the base material 22 is set on the table 53. The upper chamber 51a is lowered and the inside of the chamber 51 is made airtight with the film material 20 being sandwiched between the upper chamber 51a and the lower chamber 51b. Then, the vacuum pump 55 is operated to bring the chamber 51 into a vacuum state.

In the above vacuum state, the heater 52 is operated to heat the film material 20. This heating causes the film material 20 to hang down due to its own weight, but the film material 20 is brought into a substantially horizontal state by adjusting the degree of vacuum in the upper chamber 51a and the degree of vacuum in the lower chamber 51b. During this time, the temperature of the film material 20 is measured by a thermometer (not shown).

The temperature of the film material 20 as the molding temperature is in the range of 150 ° C. or higher and 240 ° C. or lower, and is 200 ° C. in this embodiment. Compared to the case where the molding temperature is 150 ° C. or higher, the moldability and workability are excellent compared to the case where the molding temperature is less than 150 ° C., and the molding temperature is 240 ° C. or lower, compared to the case where the molding temperature is higher than 240 ° C. This is because the occurrence of coloring is suppressed. In addition, when the molding temperature is 240 ° C. or lower, the cellulose acylate is also prevented from being thermally decomposed. The molding temperature is more preferably in the range of 180 ° C. or higher and 220 ° C. or lower. Further, the molding temperature is more preferably in the range of (Tg + 5 ° C.) or more and (Tg + 40 ° C.) or less, and (Tg + 8 ° C.) or more (Tg + 30 ° C.) or less when Tg is the glass transition point of cellulose acylate. More preferably, it is in the range. Here, although the object whose temperature is adjusted is the film material 20 in the present embodiment, the object whose temperature is adjusted is different for each thermoforming technique. For example, it is a film material in the case of vacuum pressure forming, vacuum forming, and pressure forming, a film material and a thermoplastic resin in the case of film insert molding, and a thermoplastic resin in the case of in-mold forming. Therefore, the molding temperature is the temperature of the film material in the case of vacuum pressure forming, vacuum forming, and pressure forming, the temperature of the film material and the temperature of the thermoplastic resin in the case of film insert molding, In the case, it is the temperature of the thermoplastic resin. These molding temperatures can be adjusted by the far infrared heater, the temperature of the mold to be molded, the temperature of the thermoplastic resin used for molding, and the like. Adjustment by far infrared heater is preferably used for vacuum / pressure forming, vacuum forming, and pressure forming, adjustment by mold temperature is preferably used for film insert molding, and adjustment by temperature of thermoplastic resin used for forming is film It is preferably used for insert molding and in-mold molding. Among these temperature adjustment methods, it is easy to adjust the molding temperature within a certain temperature range, the temperature to be temperature controlled can be controlled by means such as a monitor, and the temperature unevenness is small within a certain area range for molding. In view of the above, a method by adjusting the temperature of the far infrared heater or the molding die is preferable, and a method by the far infrared heater is particularly preferable.

After the molding temperature of the film material 20 reaches 200 ° C., the table 53 in the lower chamber 51b is raised. Thereby, the base material 22 on the table 53 is covered with the film material 20. In this state, the film material 20 is pressed against the base material 22 by setting the inside of the upper chamber 51a to an atmospheric pressure state. Furthermore, the film material 20 adheres to the base material 22 by operating the compressor 56 and ejecting compressed air into the upper chamber 51a. Thereby, shaping | molding of the film material 20 and bonding to the raw material 22 for base materials are performed. Thereafter, the inside of the upper chamber 51a and the lower chamber 51b is brought to atmospheric pressure, and molding is completed. The molding time is in the range of 30 seconds to 600 seconds, and in this embodiment is 180 seconds. By setting the molding time to 30 seconds or longer, the film material 20 can be molded along the shape of the base material 22 as compared with the case of less than 30 seconds, and the molding time is set to 600 seconds or less. Therefore, the contact of the saponification layer 24 in which the coloration of the film material 20 and wrinkles and / or tearing (breaking) due to heat are suppressed, and the foaming and / or coloration of the adhesive layer 27 is suppressed as compared with the case where it is longer than 600 seconds. A molded article having good antifogging properties can be obtained because the corners are small. The molding time is more preferably in the range of 60 seconds to 400 seconds, and more preferably in the range of 90 seconds to 300 seconds. And the upper chamber 51a is raised and the molded object 10 is taken out. In addition, when manufacturing a plate-shaped molded object, it is performed in said procedure. As described above, in the thermoforming method of any one of vacuum / pressure forming, vacuum forming, pressure forming, film insert forming, and in-mold forming, the base material 22 and the film material are obtained by setting the above forming temperature. The molded body 10 is excellent in moldability and workability with No. 20, and further by the above molding time, the occurrence of coloring and wrinkles and / or tears is suppressed, and the molded body 10 is excellent in transparency, antifogging properties, etc. can do.

[Example 1] to [Example 19]
In the first material forming step 31, nine kinds of film materials were produced as the first material, and film materials A to I were obtained. In the first material forming step 31, the dope used in the film material forming step 33 is completely dissolved by putting a composition having the following formulation into a hermetic container and stirring while keeping at 40 ° C. under normal pressure. I made it. The raw material for TAC is linter. The fine particles are R972 (silica manufactured by Nippon Aerosil Co., Ltd.). The fine particles were previously mixed and dispersed in a solution in which TAC was dissolved in a solvent that was a mixture of dichloromethane and methanol. And this dispersion liquid was thrown into said airtight container, and it was set as the composition of the following prescription. After standing, filter paper (No. 63, manufactured by Advantech Toyo Co., Ltd.) was used, and this liquid was filtered while being kept at 30 ° C., and after defoaming operation, a dope was obtained.

First component 100 parts by mass Second component Part by mass shown in the “Amount” column of Table 1 Dichloromethane 635 parts by mass Methanol 125 parts by mass Fine particles 1.3 parts by mass

As shown in Table 1, the first component is cellulose acylate. In Table 1, “CA” is described in the “Substance” column of “First component”. In this cellulose acylate, all acyl groups are acetyl groups, and the viscosity average degree of polymerization is 320. The acyl group substitution degree of cellulose acylate is shown in the “Acyl group substitution degree” column of Table 1.

The second component is a plasticizer, and is A to E shown in the “Substance” column of “Second component” in Table 1. A is an oligomer having a repeating unit of an ester of adipic acid and ethylene glycol (molecular weight determined by terminal functional group determination method is 1000). B is an oligomer having a repeating unit of an ester of terephthalic acid and ethylene glycol and an ester of phthalic acid and ethylene glycol (molecular weight by terminal functional group determination method is 700). C is a benzoate ester of sucrose which is an ester derivative of sugar (Monopet SB manufactured by Daiichi Kogyo Seiyaku). D is polymethyl methacrylate (PMMA). E is triphenyl phosphate (TPP) and biphenyl diphenyl phosphate (BDP). Note that “-” shown in the “Substance” column of “Second component” in Table 1 indicates that the plasticizer is not contained.

The dope whose temperature was adjusted to 30 ° C. was cast on the support. The support is an endless belt made of stainless steel. The cast film is dried by applying hot air of 100 ° C. immediately after the formation, and 120 seconds after the formation, the cast film is peeled off from the support with a peel tension of 150 N / m. A film material as an intermediate was formed. The temperature of the support at the peeling position was 10 ° C. The residual solvent amount of the cast film at the time of peeling was 100% by mass.

The dried first intermediate was dried while being transported in a state where the tension in the longitudinal direction was set to 100 N / m by a number of rolls arranged in the transport path. Drying was carried out by transporting the first drying zone set at 80 ° C. for 5 minutes and further transporting it for 10 minutes in the second drying zone set at 120 ° C. The film roll was obtained by winding up the 1st intermediate body in roll shape after drying. The width of the first intermediate was 1.5 m, and the winding length in the film roll was 2000 m. The residual solvent amount of the film material before saponification treatment at the time of winding was 0.3%.

The first intermediate was saponified in the saponification step 34 to produce a film material as the second intermediate. The saponification treatment time and treatment temperature were appropriately changed. Specifically, the second intermediate was produced by the following method. The first intermediate was unwound from the film roll and conveyed, and the saponification solution was applied to one film surface of the first intermediate by a coating device provided in the conveyance path. The prescription of the saponification solution is as follows. In the following formulation,% is a percentage by mass.
Potassium hydroxide (KOH) 3.3%
Isopropyl alcohol 88%
3% water
Propylene glycol 5%
Surfactant 0.04%

The first intermediate coated with the saponification solution was guided to the heating chamber provided in the conveyance path, heated while being conveyed, and then sent to a water tank containing water and washed with water. With respect to the long second intermediate thus obtained, the thickness, the contact angle after 15 seconds, the acyl group ratio, and the glass transition point were determined. Each method of obtaining the contact angle after 15 seconds and the acyl group ratio is as described above. The thickness is an average value of values measured at intervals of 0.5 mm in the width direction using a contact-type thickness meter. The glass transition point (Tg) of the second intermediate was determined from the following method. A sample in the form of a rectangular sheet (short side 5 mm, long side 30 mm) was conditioned for 2 hours or more at 25 ° C. and 60% relative humidity, and then the dynamic viscoelasticity measuring device DVA-225 (IT Measurement Control Co., Ltd.) The maximum temperature of tan δ (= loss elastic modulus (E ″) / storage elastic modulus (E ′)) obtained by measuring at a distance between grips of 20 mm and a frequency of 1 Hz is obtained using Tg. It was.

The adhesive layer 27 was formed on the second intermediate in the adhesive layer forming step 36. The adhesive layer 27 was formed by using a commercially available adhesive. By cutting the film material on which the adhesive layer 27 was formed in the film material cutting step 37, nine sheet-like film materials were obtained.

The film materials A to I thus obtained and the base material 22 having a dome shape or the base material having a flat plate shape are integrally formed by thermoforming using a molding device 50, respectively. Molded bodies were produced and Examples 1 to 19 were obtained. The molding temperature is shown in the “molding temperature” column of Table 2.

As the base material 22 having a dome shape, an acrylic dome having a diameter of 100 mm and a thickness of 2 mm was made of polymethyl methacrylate (PMMA), which is acrylic having a glass transition point of 100 ° C. In Table 2, “acrylic” is described in the “substance” column of “base material”, “dome” is described in the “shape” column, and “100” is described in the “diameter” column. The “diameter” is an outer diameter.

A square plate-shaped base material (not shown) is a commercially available PC plate made of PC having a glass transition point of 150 ° C. and having a side length of 100 mm and a thickness (height) of 5 mm. PC1600 manufactured by Takiron Co., Ltd.) was used. In Table 2, “PC” is described in the “Substance” column of “Substrate”, and “Plate” is described in the “Shape” column. In addition, the shaping | molding obtained by integrally shaping | molding the base material for a flat plate and the film material A which bonded the laminate film LDM-EPDC (50 micrometer) by LG Chemical as a protective layer 26 on the surface of the saponification layer 24 The body was designated Example 19.

The adhesives or pressure-sensitive adhesives used for forming the adhesive layer 27 are A to C shown in the “Adhesive layer” column of Table 2. A is an acrylic adhesive sheet manufactured by Soken Chemical Co., Ltd. B is a silicone baseless double-sided tape 91022 manufactured by 3M Corporation. C is Dianar (registered trademark) BR77 manufactured by Mitsubishi Rayon Co., Ltd.

Each of the obtained molded bodies was evaluated for rainbow unevenness, coloring, contact angle, formability to a curved surface, and workability at the end by the following evaluation methods and standards. Each evaluation result is shown in Table 2.

(1) Rainbow spotting The molded body was irradiated with fluorescent light from the substrate side, observed visually, and evaluated according to the following criteria.
Pass; color unevenness was not confirmed.
Fail: Color irregularity was confirmed.

(2) Coloring The color of the cellulose acylate film was visually observed, and the coloration of the molded product was evaluated based on the following criteria. The evaluation results are shown in the “coloring” column. 2 and 3 are acceptable.
3; Coloring was not seen in the molded product.
2: Slight coloring was observed in the molded product, but it was almost colorless.
1; The molded body was clearly brown.

(3) Contact angle The contact angle after 15 seconds was determined as described above, and this was used as the evaluation of the contact angle. As described above, a long-term antifogging property tends to be particularly good when the contact angle is 35 ° or less.

(4) Formability to a curved surface The ease with which a cellulose acylate film can be formed into an acrylic dome was evaluated according to the following criteria, and this was evaluated as the moldability to a curved surface. 3 to 5 are acceptable.
5: No floating occurred.
4; Although a slight float occurred at the end of the acrylic dome, no float occurred at the end other than the end.
3; Although floating occurred at the end of the acrylic dome, no floating occurred at the other end.
2: Floating occurred from the end to the center of the acrylic dome.
1; Wrinkles were generated in the entire bonded portion.

(5) Workability at the edge portion The ease of processing of a cellulose acylate film into a PC plate was evaluated according to the following criteria, and this was regarded as the workability evaluation. 3 and 4 are acceptable.
4; Deformed along the edge of the PC plate.
3: Although some floating occurs at the end of the PC plate, it can be bent.
2: Although bending is possible, floating occurs at the end of the PC plate.
1; Folding is impossible and floating occurs at the end of the PC board.

[Comparative Example 1] to [Comparative Example 3]
A film material J is produced by forming an adhesive layer on a polyethylene terephthalate film (Lumirror (registered trademark) U34 (for optical) 50 μm) manufactured by polyethylene terephthalate) in the same manner as in the example and cutting it into a sheet. did. In Table 1, “PET” is described in the “Substance” column of “First component”. With respect to the obtained film material J, the thickness, the contact angle after 15 seconds, and the glass transition point were determined. These results are shown in Table 1.

The film materials A and J and the base material 22 having a dome shape or the base material having a flat plate shape are integrally formed by thermoforming in the same manner as in Examples 1 to 19, and three types of molded bodies are obtained. Produced as Comparative Examples 1 to 3. The molding temperature is shown in the “molding temperature” column of Table 2.

For each molded body obtained, rainbow unevenness, coloring, contact angle, formability to a curved surface, and workability at the end were evaluated by the same method and standard as in the examples. Each evaluation result is shown in Table 2.

Claims

In the method for producing a molded article for producing a molded article having a cellulose acylate film and a transparent substrate,
A film material forming step of forming a long film material from cellulose acylate;
A molding step of forming the molded body by integrally molding the film material and a base material formed from a thermoplastic resin by thermoforming at a molding temperature within a range of 150 ° C. or higher and 240 ° C. or lower;
The manufacturing method of the molded object which has.
The method for producing a molded body according to claim 1, further comprising a film material cutting step of cutting the long film material into a sheet shape between the film material forming step and the molding step.
Between the film material forming step and the molding step, the film material has a saponification step of forming a saponified layer containing the saponified cellulose acylate,
The film material to be subjected to the molding step has an acyl group amount of the saponified layer as X, and an acyl group amount of the cellulose acylate layer formed from the cellulose acylate not saponified in the saponification step as Y. The method for producing a molded article according to claim 1 or 2, wherein the acyl group ratio obtained by X / Y is 0.7 at most.
The method for producing a molded article according to claim 3, wherein the sum of the thickness of the cellulose acylate layer and the thickness of the saponified layer is in the range of 15 µm to 100 µm.
The method for producing a molded article according to claim 3 or 4, further comprising a protective layer forming step of forming a protective layer for protecting the saponified layer on the surface of the saponified layer between the saponification step and the molding step.
The method for producing a molded body according to any one of claims 3 to 5, wherein in the molding step, the time from the start of heating to the end of molding is in a range of 30 seconds to 600 seconds.
The molding body according to any one of claims 1 to 6, wherein when the glass transition point of the cellulose acylate is Tg, the molding temperature is in the range of (Tg + 5 ° C) to (Tg + 40 ° C). Production method.
Between the film material forming step and the molding step, an adhesive layer forming step of forming an adhesive layer on the film surface of the film material,
The molded body according to any one of claims 1 to 7, wherein in the molding step, the film material and the base material are integrally formed in a state where the adhesive layer and the base material are in close contact with each other. Manufacturing method.
The method for producing a molded body according to any one of claims 1 to 8, wherein the thermoplastic resin is acrylic or polycarbonate.