JP2003205588A - Glass protecting film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass protecting film which has an excellent resistance to tear and impact that can realize prevention of breakdown and scattering of glass and is also excellent in visibility on the occasion when it is stuck on the glass, and which exhibits an excellent effect for glass protection particularly in the fields of window panes for a building material, a vehicle and glass for display such as flat display glass, and others. <P>SOLUTION: The glass protecting film is constituted of at least five layers or more and at least one of them contains a polyester having a 1,4- cyclohexanedimethanol as a component. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a glass protective film. More specifically, the present invention relates to a glass protective film suitable for protection of display glass such as CRT display, liquid crystal display, plasma display, organic EL display, field emission display, window glass for building materials and window glass for vehicles.

[0002]

2. Description of the Related Art Glass is used for various purposes because of its excellent light transmittance, gas barrier property, dimensional characteristics and the like.

In particular, window glass for building materials, window glass for vehicles,
In the field of flat displays represented by CRT displays, liquid crystal displays, plasma displays, organic EL displays, field emission displays and the like, higher performance glass is provided.

However, in these applications, there is a tendency for the display glass itself to be thin due to the demand for thinning the flat display, and accordingly, there is a problem that it is easily damaged during use.

Various methods have been proposed to prevent the problem of glass breakage and glass scattering caused by further damage by sticking a film made of a thermoplastic resin on the glass.

For example, it has been proposed that glass breakage and scattering can be largely prevented by sticking a multilayer laminated film comprising a polyethylene terephthalate layer and a sebacic acid copolymer-polyethylene terephthalate layer on the glass surface (for example, patents Reference 1).

However, although the method proposed in Patent Document 1 is effective in preventing glass from scattering,
Since the glass transition temperature of the sebacic acid copolymerization-polyethylene terephthalate layer constituting the multilayer laminated film is low, crystallization gradually occurs and whitening occurs, resulting in a phenomenon that the visible light transmittance decreases. Further, although the tear resistance of the film was improved, the impact resistance was not so effective, and the effect of preventing the breakage of the glass itself was not so great.

Therefore, it cannot be used as a glass protective film for a flat display or a window glass for a high-grade building material, in which a high visible light transmittance is continuously required and it is desired to prevent the glass itself from being broken.

[0009]

[Patent Document 1] JP-A-6-190997

[0010]

DISCLOSURE OF THE INVENTION The present invention solves the above problems, and is suitable for glass protection, particularly for glass for display such as flat display, window glass for building materials, and window glass for vehicles. The purpose is to provide a film.

[0011]

In order to solve the above problems, the glass protective film of the present invention has the following constitution.

That is, the glass protective film is characterized by comprising at least 5 layers, and at least one layer comprising a polyester containing 1,4-cyclohexanedimethanol as a constituent.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the glass protective film of the present invention will be described in detail below.

The present invention is a glass protective film comprising at least 5 layers and at least one layer containing a polyester containing 1,4-cyclohexanedimethanol as a constituent. With the glass protective film of the present invention, not only tear resistance can be improved, but also a large improvement in impact resistance and high transparency, which could not be achieved by conventional techniques, can be achieved at the same time. When the above-mentioned glass protective film is attached to glass, it becomes possible to prevent the glass from being damaged and also to ensure high visibility. Therefore, it is most suitable as a protective film for a front glass of a flat display or the like, which is difficult to use only by the glass scattering prevention function.

The glass protective film of the present invention must consist of at least 5 layers. The number of layers is preferably 10 or more, and more preferably 20 or more. When the number of layers is less than 5, it is not preferable because sufficient tear resistance and impact resistance cannot be obtained.

In particular, according to various findings of the present inventors,
The upper limit of the number of layers is not particularly limited, for example,
Although it may be about several hundred layers, it is preferable to set about 600 layers or 1000 layers from the viewpoint of production. From this, according to the knowledge of the present inventors, the range of the number of layers is preferably 20 to 1000 layers, more preferably 50 to 6 layers.
It is the 00 layer.

In the present invention, at least one layer has 1,4
It must be a layer containing a polyester composed of cyclohexanedimethanol.

More preferably, the number of layers containing the polyester having 1,4-cyclohexanedimethanol as a constituent is two or more, and further preferably three or more. Here, the polyester having 1,4-cyclohexanedimethanol as a constituent component is defined as a homopolyester or a copolyester having 1,4-cyclohexanedimethanol as a diol component of the polyester.

When at least one layer is a layer containing a polyester having 1,4-cyclohexanedimethanol as a constituent, the polyester having 1,4-cyclohexanedimethanol as a constituent is rigid and Since it is excellent in shock absorption, the layer containing the polyester containing 1,4-cyclohexanedimethanol as a constituent suppresses the propagation of cracks transmitted by impact, thus improving the tear resistance and impact resistance. It can be achieved. Further, the layer containing the polyester having 1,4-cyclohexanedimethanol as a constituent component is excellent in transparency and hardly changes in whiteness due to aging at room temperature, so that it is also excellent in visibility.

The copolymerization amount of 1,4-cyclohexanedimethanol is 10 mol% or more and 70 mol% or more.
The following are preferred. More preferably, 15 mol% or more 4
It is 5 mol% or less. More preferably, 20 mol
% And 40 mol% or less.

The intrinsic viscosity of the polyester containing 1,4-cyclohexanedimethanol as a constituent component is preferably 0.70 or more and 0.90 or less. More preferably, it is 0.73 or more and 0.85 or less. More preferably,
It is 0.75 or more and 0.83 or less. Intrinsic viscosity is 0.7
When it is less than 0, sufficient impact resistance effect cannot be obtained, and it may not be preferable depending on the application. Also, 0.9
When it is larger than 0, the laminate property tends to be poor, and the appearance tends to be deteriorated, and tear resistance and impact resistance may be deteriorated due to poor lamination accuracy, which is not preferable.

The layer constituting the glass protective film of the present invention is preferably made of a thermoplastic resin. Examples of the thermoplastic resin include polyolefin resins such as polyethylene, polypropylene, and polymethylpentene,
Polyamide resin such as nylon 6, nylon 66, polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polycarbonate resin, polyarylate resin, polyacetal resin, polyphenylene sulfide resin, acrylic resin, etc. may be used. it can. Among them, polyester is particularly preferable from the viewpoint of strength, heat resistance and transparency. Among the polyester resins, polyethylene-2,6-naphthalate and polyethylene terephthalate are preferable, and polyethylene terephthalate is particularly preferable.

These resins may be homo resins,
It may be a copolymer or a blend. Further, among these resins, various additives such as antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, organic particles, viscosity reducing agents, heat stabilizers, lubricants, infrared absorbers, and ultraviolet absorbers. Etc. may be added.

The polyester in the present invention includes a polyester resin which is a polycondensation product of a dicarboxylic acid component skeleton and a diol component skeleton, and includes, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene-
2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, etc. can be used.
In particular, polyethylene terephthalate is inexpensive,
It can be used in a wide variety of applications and is highly effective. Further, these resins may be homo resins, and may be copolymers or blends. Isophthalic acid, phthalic acid, 1, as a dicarboxylic acid component which can be copolymerized
4-naphthalene acid, 1,5-naphthalene acid, 2,6-naphthalene acid, 4,4′-diphenyldicarboxylic acid, 4,
4'-diphenyl sulfone dicarboxylic acid, sebacic acid,
An example is dimer acid.

Further, as the copolymerizable glycol component, 1,2-propanediol, 1,3-butanediol,
1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, 2,
2-bis (4′-β-hydroxyethoxyphenyl) propane, 1,4-cyclohexanedimethanol and the like can be mentioned.

In the present invention, a layer containing polyethylene terephthalate or polyethylene naphthalate as a main component, and a layer containing a copolymerized polyester containing 1,4-cyclohexanedimethanol as a main component as a main component,
It is preferable that the layers are alternately laminated in the thickness direction. More preferably, a layer containing polyethylene terephthalate as a main component and a layer containing a copolymerized polyester containing 1,4-cyclohexanedimethanol as a main component are alternately laminated in the thickness direction. In the case of such a configuration, tear resistance, impact resistance, and
High transparency can be efficiently achieved at the same time.

The thermoplastic resin constituting each layer of the present invention is
The tensile modulus is preferably 1400 MPa or more. It is more preferably 1550 MPa or more, and even more preferably 1700 MPa or more. Generally, when the tensile modulus of the thermoplastic resin is lower than 1400 MPa, whitening tends to occur over time and haze increases, which is not preferable. The upper limit of the tensile modulus is not particularly limited, but is about 5000 MPa.

Further, in the glass protective film of the present invention,
It is preferable that the following formula 1) is satisfied.

Film thickness: T (μm) Total number of layers: L 1.2 ≦ T / L ≦ 30 (Equation 1) More preferably 1.5 ≦ T / L ≦ 25, still more preferably 1. 8 ≦ T / L ≦ 20. T / L is 1.5
If it is less than the above range, the propagation of cracks due to impact cannot be sufficiently prevented, and sufficient effects on impact resistance and tear resistance cannot be obtained, which is not preferable.

In the present invention, the thickness of the layer containing the polyester containing 1,4-cyclohexanedimethanol as a constituent is preferably 0.05 μm or more and 30 μm or less. More preferably, 0.1 μm or more and 25 μm
It is the following. More preferably, 0.2 μm or more and 20 μ
m or less. The thickness of the layer containing the polyester having 1,4-cyclohexanedimethanol as a constituent component is
If the thickness is less than 0.05 μm, sufficient impact resistance cannot be obtained. If it is larger than 30 μm, sufficient tear resistance may not be obtained.

The haze of the film of the present invention is preferably 3% or less. It is more preferably 2% or less. More preferably, it is 1% or less. When the haze is larger than 3%, the visibility is lowered, which is not preferable.

In the glass protective film of the present invention, one surface layer of the film comprising at least 5 layers,
It is preferable to have an easily adhesive layer, an adhesive layer, an antireflection film, or a hard coat layer. The specific configuration of these layers is not particularly limited and can be realized by using various conventionally known techniques and the like.

By having these layers, it becomes possible to adhere it as a glass protective film to the glass of a flat display, etc., and it is possible to prevent the reflection due to the reflection on the surface and prevent the deterioration of the visibility due to scratches. This is possible, and the synergistic effect is further improved, which is preferable.

In the glass protective film of the present invention, it is preferable that the film having at least 5 layers has a pencil hardness of 2H or more on at least one side. It is more preferably 3H or more, and further preferably 4H or more. When the pencil hardness is less than 2H, it is not preferable because the surface of the film is easily scratched and the visibility is deteriorated when actually used as a glass protective film.

The near infrared ray transmittance of the glass protective film of the present invention is preferably 20% or less, more preferably 18% or less, still more preferably 16% or less.

When the near infrared transmittance is larger than 20%,
When used as a glass protective film for a plasma display, a field emission display, a CRT display, etc., near infrared rays emitted from the display may cause an abnormality in control of a remote control switch or the like through the glass protective film.

The method of setting the near infrared transmittance to 20% or less is not particularly limited, but for example, a near infrared absorber is dispersed in a thermoplastic resin or an adhesive layer, or a near infrared shielding layer is provided in a glass protective film. Alternatively, it can be achieved by providing it on a glass protective film.

The flat display element is, for example, a CRT display, a liquid crystal display, a plasma display,
It is an organic EL display, a field emission display, etc., and is particularly preferably used as a glass protective film for flat CRT displays and plasma displays.

Next, a preferred method for producing the glass protective film of the present invention will be described below.

A thermoplastic resin is prepared in the form of pellets or the like. The pellets are pre-dried in hot air or under vacuum, if necessary, and then fed to the extruder. In the extruder, the resin that has been heated and melted at a temperature equal to or higher than the melting point has a uniform amount of resin extruded by a gear pump or the like, and foreign matter or modified resin is filtered through a filter or the like. Further, the resin is ejected after being formed into a desired shape by a die.

As a method for obtaining a multilayer film,
It is possible to use, for example, a method in which thermoplastic resins sent out from different flow paths using two or more extruders are laminated in multiple layers using a multi-manifold die, a field block, a static mixer, or the like. Moreover, you may combine these arbitrarily. Further, at this time, in the present invention, at least one layer must be a polyester having 1,4-cyclohexanedimethanol as a constituent component,
The polyester containing 1,4-cyclohexanedimethanol as a constituent component is supplied to at least one extruder.

The sheet having a multi-layer structure discharged from the die is extruded on a cooling body such as a casting drum and cooled and solidified to obtain a casting film. At this time, it is preferable to use a wire-shaped, tape-shaped, needle-shaped, or knife-shaped electrode to bring it into close contact with a cooling body such as a casting drum by electrostatic force to rapidly solidify it.

The casting film thus obtained may be biaxially stretched if necessary. Biaxial stretching means stretching in the machine direction and the transverse direction.
Stretching may be biaxial stretching sequentially or may be biaxially stretching at the same time. Further, re-stretching may be performed in the machine direction and / or the transverse direction.

Here, the stretching in the longitudinal direction means stretching for imparting molecular orientation in the longitudinal direction to the film, and is usually performed by the difference in peripheral speed of rolls. This stretching may be performed in one stage, or may be performed in multiple stages using a plurality of roll pairs. The stretching ratio varies depending on the type of resin, but is usually preferably 2 to 15 times, and particularly preferably 2 to 7 times when polyethylene terephthalate is used.

The stretching in the transverse direction means stretching for imparting orientation in the width direction to the film. Usually, the tenter is used to convey the film while holding both ends of the film with clips to convey the film in the width direction. Stretch. The stretching ratio varies depending on the type of resin, but is usually preferably 2 to 10 times.

The film thus biaxially stretched is preferably subjected to a heat treatment at a stretching temperature or higher and a melting point or lower in a tenter in order to impart flatness and dimensional stability. The film is uniformly annealed and then cooled to room temperature. Being rolled up.

Although it is difficult to uniformly say that the haze of the film is 3% or less, for example,
It is effective to set the tensile elastic modulus of the thermoplastic resin constituting the glass protective film to 1400 MPa or more, and further, to make it 2% or less, for example, the particle concentration in the glass protective film is 0.02 wt% or less. What to do further
In order to set the content to 1% or less, it is effective, for example, that the glass protective film contains almost no particles, and the surface layer of the glass protective film is arranged extremely thinly by in-line coating or the like.

There are no particular restrictions on the near-infrared transmittance of 20% or less, but as described above, for example, the near-infrared absorber is dispersed in a thermoplastic resin or an adhesive layer, It is effective to provide the infrared shielding layer in or on the glass protective film. According to various findings of the present inventors, in order to reduce the content of the infrared shielding layer to 20% or less, for example, a near-infrared absorber is adhered. It is effective to disperse in a layer, and in order to achieve 18% or less, for example,
It is effective to provide the near-infrared absorbing agent on the surface layer of the glass protective film, and to make the content of 16% or less, for example, it is effective to disperse the near-infrared absorbing agent in the adhesive layer and to provide the near-infrared absorbing layer on the surface layer. is there. According to various findings of the present inventors, the lower limit of the near-infrared transmittance is 3% to 10%.
%.

The glass protective film of the present invention is a film capable of achieving both glass breakage prevention / scattering prevention and high transparency, and particularly has a high glass breakage prevention function and high transparency in flat CRT displays and plasma displays. It is suitable for a glass protective film for a flat display which is required.

[0050]

[Evaluation method for physical properties]

(1) Tear strength Tear strength was measured using a heavy load tear tester (manufactured by Toyo Seiki). Sample size is width 60mm length 70mm
Then, make a notch of 20 mm from the edge in the widthwise central part,
The indicated value when the remaining 50 mm was torn was read.
Also, multiply the indicated value (g) by 9.8 and tear strength (m
N) was calculated. The tear strength was obtained by averaging the test results of 5 samples in each of the longitudinal direction and the lateral direction. (2) Total light transmittance and haze were measured using a direct-reading haze meter (Suga Test Instruments Co., Ltd.). The haze (%) was calculated by dividing the diffuse transmittance by the total light transmittance and multiplying by 100. (3) Falling ball impact absorption energy Measured using a falling ball tester manufactured by Daiei Kagaku Seiki Seisakusho.
The measurement was made by dropping a metal ball (weight 1.809 Kg) installed at a height of 2.5 m from the film fixed on the frame to break the film, and the passing time between the upper and lower points of the test film. I asked for it. The lubricant "Three Bond 1804" was sprayed on the surface of the test film. The falling ball impact absorption energy E (J) is
The average value of 5 samples was adopted based on the following formula.

E = 1.809 × (1 / t ₀ ² −1 / t ² ) / 200 t ₀ : transit time without test film (ms) t ₁ : transit time with test film (ms) (4) Glass scattering prevention test Measured according to JIS A5759-1998 A method. When the glass is not broken, it means “Excellent”, when the glass does not scatter even if it is broken, it means “Good”, and when the glass is broken and scatters, it means “not good”. X ". Among them, excellent and good ◎ and ○ were passed. (5) Near infrared transmittance was measured using a spectrophotometer MPC-3100. Wavelength 8
The total light transmittance in the range from 00 nm to the wavelength 2100 nm is measured, and the near infrared region (800 nm to 1200 n
The average light transmittance in m) was defined as the near infrared transmittance. (6) Pencil hardness In accordance with JIS-K5400, pencils of various hardnesses were pressed against the film layer at an angle of 90 degrees and scratched with a load of 1 Kg. (7) Intrinsic viscosity Orthochlorophenol was used as a solvent and measured at 25 ° C. (8) Layer structure and layer thickness The layer structure of the film was determined by observing the cross section of the film.
That is, a transmission electron microscope HU-12 type (manufactured by Hitachi, Ltd.) was used, and the cross section of the film was 3000 to 200.
It was observed at a magnification of 000 times, a cross-sectional photograph was taken, and the layer constitution and each layer thickness were measured. (9) Tensile Elastic Modulus (Young's Modulus) The Young's modulus of the thermoplastic resin forming each layer is measured according to ASTM test method D882-88. The sample film was an unstretched film obtained by rapidly cooling and solidifying on a casting drum controlled at a temperature of 25 ° C. and improving the adhesion between the drum and the film using an electrostatic applying device. The measurement was carried out using an Instron type tensile tester (Automatic film strength and elongation measuring device “Tensilon AMF / RTA-100” manufactured by Orientec Co., Ltd.), and a sample film having a width of 10 mm was tested. 100m
The Young's modulus was obtained by pulling under the conditions of m and a pulling speed of 200 mm / min. (Example 1) As the thermoplastic resin A, polyethylene terephthalate having an intrinsic viscosity of 0.8 was used. Further, as the thermoplastic resin B, 1,4-cyclohexanedimethanol is 10
mol% copolymerized polyester (Eastman Chemical Co., Ltd. East PETG9921)
Was used. These thermoplastic resins A and B were each dried and then supplied to the extruder. The thermoplastic resin A
Had a tensile elastic modulus of 1800 MPa, and the thermoplastic resin B had a tensile elastic modulus of 1720 MPa.

The thermoplastic resins A and B were melted at 280 ° C. in an extruder, passed through a gear pump and a filter, and then joined in a feed block.
The combined thermoplastic resins A and B were supplied to a static mixer to have a structure in which the thermoplastic resin A was composed of 65 layers and the thermoplastic resin B was composed of 64 layers and were alternately laminated in the thickness direction. Here, the discharge amount was adjusted so that the laminated thickness ratio was A / B = 5. The thus obtained laminate having a total of 129 layers was supplied to a T-die and formed into a sheet, and then rapidly cooled and solidified on a casting drum whose surface temperature was kept at 25 ° C. while applying static electricity.

The cast film obtained was heated by a group of rolls set at 90 ° C., stretched 3.2 times in the machine direction, guided to a tenter, preheated with hot air at 100 ° C., and then stretched in the transverse direction 3.
It was stretched 3 times. The stretched film was heat-treated as it was in a tenter with hot air at 150 ° C., gradually cooled to room temperature, and then wound. The thickness of the obtained film is 188μ.
It was m. The results obtained are shown in Table 1. (Example 2) A stretched film having a total of 65 layers was obtained according to Example 1 and the apparatus and conditions. However, if the thermoplastic resin A is 3
A laminated film composed of 3 layers and 32 layers of the thermoplastic resin B is formed, and the thickness of the film is 188 μm by adjusting the discharge amount of the resin.
So that The results obtained are shown in Table 1. (Embodiment 3) With the same apparatus and conditions as in Embodiment 1, a total of 3
A stretched film having three layers was obtained. However, as the laminating apparatus, only a 33-layer laminated feed block was used, and a laminated film composed of 17 layers of thermoplastic resin A and 16 layers of thermoplastic resin B was used, and the thickness of the film was 188 μm by adjusting the discharge amount of the resin. I tried to be. The results obtained are shown in Table 1. (Embodiment 4) Using the same apparatus and conditions as in Embodiment 1, a total of 1
A stretched film consisting of 7 layers was obtained. However, as the laminating device, only a 17-layer laminated feed block was used, and a laminated film composed of 9 layers of thermoplastic resin A and 8 layers of thermoplastic resin B was used, and the discharge amount of the resin was adjusted to make the film thickness 1
It was set to be 88 μm. The results obtained are shown in Table 1. (Embodiment 5) A total of 7 devices were obtained under the same apparatus and conditions as in Embodiment 1.
A stretched film consisting of layers was obtained. However, as the laminating apparatus, only a 8-layer multi-manifold die was used, and a laminated film composed of 4 layers of thermoplastic resin A and 3 layers of thermoplastic resin B was used, and the film discharge amount was adjusted to 18
It was set to 8 μm. The results obtained are shown in Table 1. (Embodiment 6) With the same apparatus and conditions as in Embodiment 2, a total of 6
A stretched film having 5 layers was obtained. However, the lamination thickness ratio A / B of the thermoplastic resin A and the thermoplastic resin B was set to 2, and the discharge amount of the resin was adjusted so that the film thickness became 188 μm. The results obtained are shown in Table 1. (Embodiment 7) Using the same apparatus and conditions as in Embodiment 2, a total of 6
A stretched film having 5 layers was obtained. However, the lamination thickness ratio A / B of the thermoplastic resin A and the thermoplastic resin B was set to 10, and the discharge amount of the resin was adjusted so that the film thickness became 188 μm. The results obtained are shown in Table 1. (Embodiment 8) A total of 6 devices are manufactured under the same apparatus and conditions as in Embodiment 2.
A stretched film having 5 layers was obtained. However, as the thermoplastic resin A, polyethylene terephthalate having an intrinsic viscosity of 0.65 was used. The results obtained are shown in Table 1. The tensile modulus of the thermoplastic resin A was 1800 MPa. (Embodiment 9) Using the same apparatus and conditions as in Embodiment 2, a total of 6
A stretched film having 5 layers was obtained. However, the thermoplastic resin B contains 1,4-cyclohexanedimethanol at 30 mo.
1% copolymerized polyester (Eastman
Eatster PETG6763 manufactured by Chemical Co. was used. The results obtained are shown in Table 1. The tensile modulus of the thermoplastic resin B was 1720 MPa. (Example 10) A stretched film having a total of 65 layers was obtained by the same apparatus and conditions as in Example 2. However, the thermoplastic resin B contains 100 parts of 1,4-cyclohexanedimethanol.
Polycyclohexane dimetallate (PCT) polymerized in mol% was used. The results obtained are shown in Table 1. The tensile modulus of the thermoplastic resin B was 1750 MPa. (Example 11) By the same apparatus and conditions as in Example 2, a stretched film having a total of 65 layers was obtained. However, the thermoplastic resin B is a copolymerized polyester obtained by copolymerizing 1,4-cyclohexanedimethanol and isophthalic acid (Duraster DS201 manufactured by Eastman Chemical Co., Ltd.).
0) was used. The results obtained are shown in Table 1. The tensile modulus of the thermoplastic resin B was 1740 MPa. (Example 12) A stretched film having a total of 65 layers was obtained under the same apparatus and conditions as in Example 2. However, the discharge amount of the resin was adjusted so that the film thickness became 150 μm. The results obtained are shown in Table 1. (Example 13) By the same apparatus and conditions as in Example 2, a stretched film having a total of 65 layers was obtained. However, the discharge amount of the resin was adjusted so that the film thickness was 120 μm. The results obtained are shown in Table 1. (Example 14) A stretched film having a total of 65 layers was obtained by the same apparatus and conditions as in Example 2. However, the discharge amount of the resin was adjusted so that the film thickness became 100 μm. The results obtained are shown in Table 1. (Example 15) A stretched film having a total of 65 layers was obtained by the same apparatus and conditions as in Example 2. However, the heat treatment temperature was set to 220 ° C. The results obtained are shown in Table 1. (Example 16) A stretched film having a total of 65 layers was obtained by the same apparatus and conditions as in Example 2. However, the thermoplastic resin A contains polyethylene terephthalate (glass transition temperature: 76 ° C.) having an intrinsic viscosity of 0.8 and 1 wt% of an infrared absorber.
% Was used. The results obtained are shown in Table 1.
The near infrared ray transmittance was 16%. (Example 17) By the same apparatus and conditions as in Example 2, a stretched film having a total of 65 layers was obtained. However, particle size 30n
An easily-adhesive coating layer composed of m silica particles and a polyester resin was provided on one surface of the film. The results obtained are shown in Table 1. (Example 18) By the same apparatus and conditions as in Example 2, a stretched film having a total of 65 layers was obtained. However, particle size 30n
An easily-adhesive coating layer composed of m silica particles and a polyester / polyurethane resin was provided on one side of the film. The results obtained are shown in Table 1. (Example 19) A stretched film having a total of 65 layers was obtained by the same apparatus and conditions as in Example 2. However, particle size 30n
An easily-adhesive coating layer composed of m silica particles and an acrylic resin was provided on one surface of the film. The results obtained are shown in Table 1. (Example 20) An antireflection layer and a hard coat layer having a pencil hardness of 4H were provided on one surface of a stretched film having a total of 65 layers of Example 17, and an adhesive layer was provided on the other surface. The results obtained are shown in Table 1. (Example 21) Under the same conditions and conditions as in Example 17, a stretched film having a total of 33 layers was obtained. However, the thermoplastic resin B is a copolymerized polyester obtained by copolymerizing 1,4-cyclohexanedimethanol at 30 mol% (Ea manufactured by Eastman Chemical Co., Ltd.
tsterPETG6763), using only a 33-layer laminated feed block as a laminating device, and forming a laminated film comprising 17 layers of thermoplastic resin A and 16 layers of thermoplastic resin B, and a lamination ratio (A / B) of 10: It was set to 1. In addition, the thickness of the film is adjusted to 188 μm by adjusting the discharge amount of resin.
So that The results obtained are shown in Table 1. (Comparative Example 1) The following single film was obtained by the same apparatus and conditions as in Example 1. That is, only one extruder was used, a field block and a static mixer were not used, and polyethylene terephthalate having an intrinsic viscosity of 0.8 was used as the thermoplastic resin to form a single film. The thickness of the obtained film was 188 μm. The results obtained are shown in Table 1. (Comparative Example 2) The following monolayer film was obtained by the same apparatus and conditions as in Example 1. That is, only one extruder was used, a field block and a static mixer were not used, and as the thermoplastic resin, a copolymerized polyester (PETG9921 manufactured by Eastman) in which 10 mol% of cyclohexanedimethanol was copolymerized was used. It was a membrane film. The thickness of the obtained film is 188 μm
Met. The results obtained are shown in Table 1.

[0054]

[Table 1]

[0055]

Industrial Applicability According to the present invention, it is possible to provide a glass protective film which has both tear resistance and impact resistance for the purpose of preventing breakage and scattering of glass, and visibility when attached to glass. In particular, it is possible to provide a glass protective film suitable as a protective film for a window glass for building materials, a window glass for vehicles, a display glass for a flat display and the like.

Continued front page    F term (reference) 4F100 AK01A AK01B AK41A AK41K                       AK42B AK42K AR00C AR00D                       BA02 BA04 BA05 BA08 BA10C                       BA10D GB07 GB31 GB41                       JB16A JB16B JD05 JK03                       JK07A JK07B JK10 JK12D                       JN06C YY00 YY00A YY00B                       YY00D                 4J004 AB01 CA06 CB03 CC02 FA01                       FA04

Claims (14)

[Claims] 1. A glass protective film comprising at least 5 layers, and at least one layer containing a polyester containing 1,4-cyclohexanedimethanol as a constituent. 2. A layer containing polyethylene terephthalate or polyethylene naphthalate as a main component, 1,4
The glass protective film according to claim 1, wherein layers having a copolyester having cyclohexanedimethanol as a main component as a main component are alternately laminated in the thickness direction. 3. At least 5 or more layers are each made of a thermoplastic resin, and a thermoplastic resin constituting each layer has a tensile elastic modulus of 1400 MPa or more. Item 2. The glass protective film according to item 2. 4. The glass protective film according to any one of claims 1 to 3, wherein the copolymerization amount of 1,4-cyclohexanedimethanol is 15 mol% or more and 45 mol% or less. 5. The glass protective film according to claim 1, which has a haze of 3% or less. 6. The glass protective film according to claim 1, which satisfies the following formula 1). Film thickness: T (μm) Total number of layers: L 1.2 ≦ T / L ≦ 30 (Equation 1) 7. A layer containing a polyester having 1,4-cyclohexanedimethanol as a constituent component has a thickness of 0.
The glass protective film according to claim 1, wherein the glass protective film has a thickness of 05 μm or more and 30 μm or less. 8. The glass protective film according to any one of claims 1 to 7, further comprising an adhesive layer on at least one side thereof. The glass protective film as described in any of the above. 9. The glass protective film according to any one of claims 1 to 8, further comprising an antireflection film on at least one surface thereof.
To the glass protective film according to claim 8. 10. The glass protective film according to claim 1, wherein at least one side has a pencil hardness of 2H or more. 11. The glass protective film according to claim 1, which has a near-infrared transmittance of 20% or less. 12. The glass protective film according to any one of claims 1 to 11, which is used by being attached to a building material window glass or a vehicle window glass. 13. The glass protective film according to any one of claims 1 to 11, which is used by being attached to the front surface of the glass for a flat display element. 14. The glass protective film according to claim 13, wherein the flat display element is a flat CRT display or a plasma display.