JPS6063151A - Polyester film for evaporating metallic thin-film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a polyester film for wearing a metal thin film lid.

[Prior art]

Applications of polyester films for metal thin film deposition include vapor deposition type capacitors, decorative vapor deposition polyester films, and vapor deposition magnetic tapes.

The characteristics required for the base film for these applications are common. That is, the surface smoothness, runnability, and durability of the base film, as well as the smoothness, runnability, and durability of the surface of the vapor-deposited film formed by vapor-depositing the vapor-deposited substance on the base film.

Since the thickness of the deposited film is very thin, the surface of the deposited film maintains its base film surface morphology almost unchanged. Application characteristics such as capacitor capacity, vapor deposition surface gloss.

In order to dramatically improve the electromagnetic characteristics of a magnetic tape, it is essential that the surface of the deposited film be as smooth as possible. For this purpose, the surface of the base film must be as smooth as possible. Considering extreme cases, it may be preferable to use a base film made of a completely mirrored surface.

However, the runnability and durability of such base film surfaces are extremely poor, at all stages before and during the deposition process.

A large number of scratches occur due to poor wrinkle handling.
Various problems occur, such as the inability to drive. The surface of the vapor-deposited film deposited on the base film with such large scratches will have scratches on its surface shape and will not satisfy the required quality characteristics, and the surface of the vapor-deposited film itself will have scratches. Since it maintains a mirror surface except for the areas marked above, its running performance and durability are very poor.

Even in the processes after the vapor deposition step, a large number of scratches occur, making it completely impractical. Furthermore, not only the vapor deposition process but also the runnability and durability of the vapor-deposited surface after the actual product is made are required, but these requirements cannot be met by using the above-mentioned base film.

[Purpose of the invention]

An object of the present invention is to provide a polyester film for metal thin film deposition that improves not only the base film itself but also the smoothness, resistance to unevenness, and runnability of the deposited film provided thereon. .

[Structure of the invention]

The present invention has the following configuration to achieve the above object.

That is, it consists of a polyester film and a full-surface coating layer that is closely adhered to at least one side of the film, and in the coating layer, there are 1 x 10 protrusions with a maximum length of 0.005 to 10μ.
It is characterized by a polyester film for metal thin film deposition, in which the coating layer has a PV value of 20 to 1 oooX as a whole.

The polyester film of the present invention is a polyester film formed by a biaxial stretching method.

Polyester is melted and extruded into sheets or cylinders,
A film formed by stretching this in at least one direction, and the mechanical properties of the film are as follows.

It is desirable to be one of a normal balanced type, a -axially strengthened type, and a biaxially strengthened type. Further, the surface of the polyester film is desirably smooth, and specifically, the roughness of the film surface is a cutoff value of 0080 on a stylus type surface roughness meter, and an Ra value of 0.015μ or less.

More preferably within the range of 0.010 to 0.002μ,
It is desirable that there be.

Note that the Ra value is the roughness value measured by using an appropriate cutoff value from the cross-sectional curve obtained from a stylus surface roughness meter, and measuring the center line (above and below the center line) of the roughness curve excluding waviness. is the arithmetic mean of the absolute values of the roughness curve from
(according to Engineering N476B).

The polyester forming the film may be any polyester as long as it is mainly composed of linear polyester. For example, polyethylene terephthalate, polytetramethylene terephthalate.

Typical examples include poly-1,4-cyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalene dicarboxylate, and polyethylene-p-oxybenzoate.

The above polyester may be a homopolyester or a copolyester. In the case of copolyester, as a component to be copolymerized.

For example, diethylene glycol, propylene glycol, neopentyl glycol, polyethylene glycol,
Diol components such as p-xylylene glycol and 1,4-cyclohexane dimetatool.

Adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2
, 6-naphthalene dicarboxylic acid, 5-sodium sulfoisophthalic acid and other dicarboxylic acid components.

Examples include polyfunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid, and p-oxyethoxybenzoic acid. In the case of copolymerization, the amount of components to be copolymerized is 20 molar or less.

Furthermore, the above-mentioned polyester is mixed with at least one of an alkali metal salt derivative of sulfonic acid that is non-reactive with the polyester, a polyalkylene glycol that is substantially insoluble in the polyester, etc., to an extent not exceeding 5% by weight. It's okay. However, when the film is stretched, it may contain internal particles consisting of polymerization residues that cause protrusions on the film surface, or inert particles added from the outside, and their content is determined by their content. When this polymer is biaxially stretched, it is sufficient that the thickness is 60 μm or less and the haze per sheet is 5% or less.

The coating layer of the present invention is an entire surface coating layer made of an organic polymer containing particles having a maximum length of 0.005 to 10 μm. The thickness is in the range of 0.005 to 2μ.

Any organic polymer may be used as long as it does not impede the object of the present invention. Specific examples of organic polymers include water-soluble polymers.

That is, polyvinyl alcohol, gum tragacanth gum arabic, casein, gelatin, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinyl methyl ether 1 sodium polyacrylate, polyvinyl pyrrolidone, sodium alginate, water-soluble polyester resin, etc. can be used. Also, organic polymers with film-forming properties such as polystyrene, polyethylene, and polyamide.

Polyester, polyacrylic acid ester, polymethyl methacrylate, polyepoxy resin, polyvinyl acetate, acrylic-styrene copolymer resin, etc. can be used.

The above-mentioned coating layer contains particles with a maximum length o, oos to 1oμ. These particles should be of a uniform size. The maximum length of this particle is o, o o s~
A 10 μm protrusion on the surface of the coating layer is formed.

These surface protrusions improve the running properties of the space surface and the metal vapor deposited thin film surface. The number of protrusions formed on the surface, that is, the surface protrusion density is 1 x 10' to 1 x 1010 cases/2. It is preferable that the surface of the coating layer between the formed protrusions is smooth. What does smooth mean here?

There should be no irregularities such as wrinkles. That is, when observing the protrusion-forming surface using an electron beam microscope.

No structure is observed between the protrusions.

demand. Specifically, the surface of the coating layer is photographed at a magnification of 10,000 times using an electron microscope, the maximum length of at least 10 protrusions in the photograph is measured, and the average value is determined as the maximum length of the protrusions. Satoru. Also.

Five photographs are taken at the same magnification, and the number of protrusions having a predetermined maximum length in each photograph is counted, and the value converted to the number per unit area is defined as the number of protrusions. The maximum length of the particles in the coating layer is measured by exposing the particles in the coating layer using various etching methods and using the same method as the above-mentioned microscopic observation. However, if the microscope magnification is inappropriate, use different magnifications together.

Moreover, the PV value of the surface of the coating layer is 20 to 1000X.

It is preferably 20 to 500A. The TPV value here is an abbreviation for peak-to-valley value.

Maximum surface roughness specified in J Engineering S BO601.

This is a value measured according to Rmax. This is actually measured using a high-precision stylus type surface roughness measuring device.

The maximum length of the particles is o, oos to 1oμ, preferably 0.
08-1.0μ. If the maximum length is less than 0.005μ, the maximum length of the surface protrusions formed by the particles will be less than 0.005μ, and the running properties of the base surface and the surface of the deposited film will deteriorate. When the maximum length exceeds 10μ, the maximum length of the surface projections formed on the particle is 10μ.
If it exceeds μ, there is a tendency to deteriorate various required characteristics (capacitance, gloss, electromagnetic conversion characteristics, etc.) of the surface of the deposited film. The shape of the particles is spherical, ellipsoidal, rectangular, cubic, etc.

The number of surface protrusions formed by particles is 1x10'~1x
1010 pieces/w2+ Good 1 L<Ha1 x 10”
-1x 10' pieces/mm2. The number of protrusions on this surface is 1
If it is less than x10'/2, the runnability of the base surface and the surface of the deposited film will deteriorate. When the number of protrusions exceeds 1 x 10''/mn12, various required characteristics of the surface of the deposited film (capacitance, gloss, electromagnetic conversion characteristics, etc.) deteriorate.

The pv value of the surface of the coating layer is preferably 20 to 1oooX, more preferably 2o to 5ooX. If the EV value of the surface of the coating layer is less than 2O2, the surface of the paste and the surface of the deposited magnetic film will be too smooth, resulting in poor running performance.

The pv value of the surface of the coating layer is i oo.

If A is exceeded, the surface of the deposited film becomes too rough and various required characteristics (
capacitor capacity, gloss, electromagnetic conversion characteristics, etc.).

The particles may be either organic or inorganic compounds as long as they have a maximum length of 0.005 to 10 μm. An example of an organic compound is polystyrene.

Polyethylene, polyamide, polyester, polyacrylate, polymethyl methacrylate.

Fine particles made of polyepoxy resin, polyvinyl acetate, acrylic-styrene copolymer resin, etc. can be used. Polymer aggregates, micelles, etc. can also be applied. Mg as an inorganic compound
O, ZnO, MgC0, caco, lCaSO4,
Ba804. Al, 0. , 5i02. TiO2-p
Ca.

Acid salts such as Ba, Zn, Mn, etc. can be used. Particle types with relatively uniform size are used.

Since the particles are present in the coating layer, they are unlikely to fall off. The durability of the surface protrusions is good.

Other components may be included in the coating layer to improve the adhesion between the particles and the coating layer as well as between the coating layer and the polyester film.

Other ingredients include, for example, a coupling agent.

That is, a silane coupling agent, a titanium coupling agent, etc. can be used.

As a silane coupling agent, it is an organosilicon polymer having two or more different reactive groups in its molecule; one of the reactive groups is a methoxy group, ethoxy group, silanol group, etc., and the other is a methoxy group, an ethoxy group, a silanol group, etc. The silane coupling agent that binds to the reactive group and polyester is selected, including vinyl trichlorosilane, vinyl tri Propyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptosilopyltrimethoxysilane, γ-aminopropyltriethoxysilane, etc. can be used.

Isopropyl tristearoyl titanate and the like can be used as the titanium coupling agent.

The polyester film for metal thin film deposition of the present invention will be explained below based on one drawing.

FIG. 1 is a schematic plan view of a surface coating structure obtained by observing nine films of the present invention using an electron microscope. Magnification factor 1
This state can be seen by observing it with an electron microscope at a magnification of 10,000 times or more.

Figure 2 shows that the polyester film and the coating layer are in close contact with each other.
FIG. 3 is a schematic cross-sectional view showing the state in which particles are contained in the coating layer.

In the figure, P may be a polyester film, and A may be during layering.

The vapor-deposited product can be obtained by providing a thin film according to each application on the surface of the above-mentioned coating layer of the polyester film for vapor deposition of the present invention by vapor deposition.

The runnability and sluggishness of the surface of the coating layer of the polyester film according to the present invention and the vapor-deposited surface on which a metal vapor-deposited film is formed are evaluated by measuring the coefficient of dynamic friction with a fixed metal guide rod.

The scratch resistance is evaluated by observing the surface abrasion state by repeatedly contacting and running with a fixed metal guide rod 500 times.

1 As a required property, the glossiness of the salmon-deposited surface is visually determined.

The surface of the above-mentioned coating layer of the polyester film of the present invention and the surface on which the metal vapor-deposited film is provided have extremely small contact areas with various metal guides, process metal rolls, etc., and therefore have poor running performance.

Durability and abrasion resistance are extremely good. In addition, when a metal vapor deposited film is provided, its surface roughness is very small, and the surface morphology is also very fine and smooth, so it has various characteristics (capacitor capacity) required for the vapor deposited film surface.

It also has excellent gloss, electromagnetic conversion properties, etc.).

Next, two manufacturing methods of the present invention will be explained. However, the manufacturing method is not limited to this. A coating liquid consisting of a coating layer consisting of an organic polymer containing the components to become particles as described above is applied to at least one side of a smooth polyester film after being stretched in one direction by a conventional method, or after being stretched in a perpendicular direction. , further stretched in the one direction and heat treated.

〔Effect of the invention〕

As described above, in the present invention, a coating layer containing one particle is adhered to the surface of a polyester film, and protrusions are formed on the surface of the coating layer, so that the coating layer and the coating layer formed thereon are The running performance of the surface of the vapor-deposited film is dramatically improved.

Furthermore, since the pv value of this coating layer is 1000 A or less, various properties required for the surface of the deposited film (capacitance, gloss, electromagnetic conversion properties) are not impaired.

〔Example〕

Next, an example will be described.

Example 1 A substantially non-oriented, non-crystalline polyethylene terephthalate raw material containing as few internal particles as possible due to residual polymerization catalyst, etc., was melt-extruded onto a rotating drum maintained at about 20°C, and then 3. The film was stretched 4 times in the machine direction, and then the following aqueous emulsion was coated on both sides at a solid content concentration of 20 mg/m2 using a metering bar coater.

As an aqueous emulsion, methylcellulose o, i
s wt%, HoIJ acrylic ester emulsion (solid content concentration 40 eIb) 1.0 wt% and silane coupling agent N-β (aminoethyl)γ-aminopropylmethyldimethoxysilane 0.025% was prepared. did. The drying, preheating, and stretching temperatures were 95°C.

E on both sides at 3.4 times the transverse stretching ratio and 200°C heat treatment temperature.
6 x 10 protrusions with a V value of 250^ and a maximum length of 0.15μ
6 pieces/m [l] 2 Thickness of the formed coating layer in close contact 1
A 2μ polyethylene terephthalate film was obtained.

An A1 thin film having a thickness of 1500× was formed on the surface of this polyester film by vacuum deposition. Table 1 shows the characteristics of the base film and the deposited film.

Example 2 Example 10 The polyacrylic acid ester emulsion in the aqueous emulsion used in base film production was replaced with polyvinyl acetate emulsion (solid content 35%) 1.0 wt.
I changed it to %. Do the same for the rest, pv value 2 on both sides.
A polyethylene terephthalate film having a thickness of 12 μm and having a covering layer of 5×10′/−2 formed with 80× and a maximum length of 0.2 μm was obtained.

This base film was used in the same manner as in Example 1, and the characteristics of the base film and the deposited film surface are shown in Table 1.

Example 3 In the production of the base film of Example 1, the polyacrylic acid ester emulsion in the aqueous emulsion used was mixed with ultrafine silica sol (solid content: 20 cm).

Particle size: 0.02 μ) D, 5 wt%. The rest was made in the same way, with a pv value of 200A on both sides, and a maximum length of 0.
A polyethylene terephthalate film having a thickness of 12 μm and having a coating layer in which 8 x 10 8 protrusions/a2 of 0.2 μm in thickness were adhered was obtained.

This base film was used in the same manner as in Example 1, and the characteristics of the base film and the deposited film surface are shown in Table 1.

Comparative Example 1 In manufacturing the base film of Example 10, the use of polyacrylic acid ester emulsion in the aqueous emulsion used was discontinued. The rest is the same, with a pv value of 10 on both sides.
A polyethylene terephthalate film with a thickness of 12 μm was obtained, to which a coating layer with no protrusions was adhered.

This base film was used in the same manner as in Example 1, and the characteristics of the base film and the deposited film surface are shown in Table 1.

Comparative Example 2 In the production of the base film of Example B, the particle size of the ultrafine silica sol used was changed to 0.004 μm. The rest is the same, with a pv value of 60 on both sides, and a maximum length of 0. A polyethylene terephthalate film having a thickness of 12 μm was obtained, to which a coating layer having 6×10 8 protrusions/1 m 12 oO-sized projections was closely adhered.

This base film was used in the same manner as in Example 1, and the characteristics of the base film and the deposited film surface are shown in Table 1.

Comparative Example 3 In manufacturing the base film of Example 10, alumina sol (solid content concentration 30%, major axis 1
5μ) was replaced with 0.5wt1.

The rest is the same, PV value 400X on both sides, maximum length 1
A polyethylene terephthalate film having a thickness of 12 μm was obtained, to which a coating layer having 6×10 5 protrusions/mII+2 of 5 μm was closely adhered.

This base film was used in the same manner as in Example 1, and the characteristics of the base film and the deposited film surface are shown in Table 1.

Comparative Example 4 In the production of the base film of Example 1, the aqueous solution x used
The concentration of polyacrylate emulsion in the fulsion was changed to 0.10 wt%. The other parts were made in the same way. 5 protrusions with a pv value of 200 and a maximum length of 0.15μ were placed on both sides.
A polyethylene terephthalate film having a thickness of 12 μm and having a coating layer of x 10′/l1o2 formed thereon was obtained.

Comparative Example 5 In manufacturing the base film of Example 30, the concentration of ultrafine silica and sol in the aqueous solution used was 2. Changed to Qwt%.

The rest is the same, with a pv value of 250^ on both sides.

4 x 1 protrusions with a maximum length of 0.02p [1” / l
A polyethylene terephthalate film with a thickness of 12 μm was obtained, to which a coating layer formed with Im+2 was adhered.

1) Run the film on a metal (SUE) fixed guide rod in the form of a tape and run it once at 180°, and check the dynamic coefficient μ. (However, under normal temperature and normal humidity conditions) ○: μm = o, 1o
~0.49 x~○: 0.50 to 1 in μ, O and observe the scratches on the film. (However, under normal temperature and normal humidity conditions) ○: Very little scratches X: Large scratches 3) Gloss A1 The surface gloss of the vapor-deposited coating layer is visually judged.

◎: Very good gloss O: Good gloss Δ: Surface gloss Poor ×: Low light reflectance, no gloss at all As is clear from the property results in Table 1, the surface to which the coating layer of the present invention was adhered and The surface of the vapor-deposited thin film with the vapor-deposited film formed on its surface side has good running properties and scratch resistance, and is smooth and has excellent practical properties.

[Brief explanation of the drawing]

FIG. 1 is an enlarged plan view schematically showing the surface of the coating layer of the present invention, and FIG. 2 is a sectional view schematically showing the cross section of FIG. 1. F' = Base film A: Covering layer B: Particle patent applicant Toshi Co., Ltd.

Claims (1)

[Scope of Claims] A polyester film and a coating layer closely adhered to at least one side of the film, and particles having a maximum length of 0.005 to 10 μm are present in the coating layer. Accordingly, on the surface of the coating layer, a maximum length of 0.005 to 1
0/J protrusions are 1 x 104 to 1 x 1o10 pieces/TlB
2 is formed, and the pv value of the surface of the coating layer as a whole is 20 ~
Polyester film for metal thin film deposition, characterized by being 1oooX