JP5549483B2 - Vapor deposition material, gas barrier vapor deposition film manufacturing method, and gas barrier vapor deposition film - Google Patents

Description

  The present invention relates to a vapor deposition material and a gas barrier vapor deposition film.

  Gas barrier vapor-deposited films are widely used in the field of components that need to block oxygen and water vapor in the field of packaging of solar cell backsheets, foods, pharmaceuticals, etc., or in non-packaging fields.

  It is necessary to protect the contents of precision electronic parts such as hard disks and semiconductor modules, or packaging materials used for packaging foods and pharmaceuticals. Particularly in food packaging, it is necessary to suppress the oxidation and alteration of proteins, fats and oils, and to maintain the taste and freshness.

  In order to prevent the active ingredient from being altered and maintain its efficacy in pharmaceuticals that require handling under aseptic conditions, and to prevent corrosion of metal parts and poor insulation in precision electronic parts. There is a need for a package having a gas barrier property that blocks oxygen, water vapor, and other gases that alter the contents of the packaging material.

  Therefore, metal foils such as aluminum and aluminum vapor deposited films that have not been affected by temperature and humidity, or polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), polyacrylonitrile (PAN). ) And plastic films laminated or coated with these resins have been used favorably.

  However, packaging materials using metal foils such as aluminum and aluminum vapor-deposited films are excellent in gas barrier properties, but are opaque, so it is difficult not only to identify the contents through the packaging material, but also after use. However, it has the disadvantages that it must be treated as an incombustible material at the time of disposal, a foreign matter inspection using a metal detector, and a heat treatment in a microwave oven cannot be performed.

  In addition, a gas barrier resin film or a film coated with a gas barrier resin is highly temperature dependent and cannot maintain high gas barrier properties. Furthermore, PVDC, PAN, and the like after use have a problem that they may cause harmful substances during disposal and incineration.

  Therefore, as a packaging material that overcomes these drawbacks, a gas barrier film in which an inorganic oxide such as magnesium oxide, calcium oxide, aluminum oxide, or silicon oxide is vapor-deposited on a transparent base film has recently been put on the market.

  These gas barrier vapor-deposited films are known to have transparency and gas barrier properties such as oxygen and water vapor, and are suitable as packaging materials having both transparency and gas barrier properties that cannot be obtained with metal foil or the like. A film on which silicon oxide SiOx is deposited is used as a food packaging film. In addition, vapor deposition by a heating method using silicon oxide SiOx as a vapor deposition material has a very high film formation rate and high productivity.

However, the silicon oxide SiOx (0 <x <2), which is a deposition material used here, is manufactured by vacuum deposition using metal silicon and silicon dioxide as raw materials, and thus has the following drawbacks. ing.

  Since silicon oxide SiOx (0 <x <2), which is a material for vapor deposition produced by vacuum vapor deposition, is not a production method suitable for mass production, there is a problem that the material cost is high and the production cost is high. Further, the silicon oxide SiOx (0 <x <2) of this vapor deposition material has a density close to the true density and has a very dense structure.

  Therefore, when a barrier film is produced by evaporating this deposition material, unvaporized deposition material is scattered as high-temperature particles due to thermal shock caused by heating during vapor deposition or the pressure of gas generated from the inside. There is a problem that a phenomenon called splash occurs.

  When high-temperature particles reach the polymer film, pinholes and foreign matters are generated, resulting in a decrease in barrier properties and poor appearance. Further, in the heating method described above, particularly heating by an electron gun, the above-described splash and foreign matter are more noticeably generated when the deposition material receives a larger thermal shock.

On the other hand, the mixed vapor deposition material of metal silicon and silicon dioxide is relatively inexpensive, but it is difficult to evaporate because it has a higher vapor pressure than silicon monoxide during heating, and it is a melt type vapor deposition material. Therefore, a larger thermal shock is required, and the vapor deposition material is scattered and splash is likely to occur. In addition, the generation of oxygen gas due to the decomposition of silicon dioxide increases the pressure in the film formation chamber, resulting in a decrease in deposition rate, that is, a decrease in productivity, and a decrease in barrier properties of the deposited film due to a decrease in deposited film density. There is also a problem.
Known documents are shown below.

JP-A-9-143690 JP 2009-280832 A

  The present invention is intended to solve the above-described problems of the prior art, and a vapor deposition material containing metal silicon and silicon oxide that can suppress the occurrence of a splash phenomenon, and a gas barrier vapor deposition film deposited using the material. The purpose is to provide.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and the invention according to claim 1 is a heating type vapor deposition material in which silicon dioxide and zinc sulfide or metal silicon, silicon dioxide and zinc sulfide are mixed. The ratio of the total number of atoms of silicon and zinc sulfide to the number of oxygen atoms (O / (Si + ZnS)) is 0.75 to 1.75, and the bulk density is 0.8 to 1.5 g / It is in the range of cm ³ , and silicon dioxide is a vapor deposition material characterized by containing at least 20% or more of a crystal structure .

The invention according to claim 2 of the present invention is the material for vapor deposition according to claim 1, wherein the shape of the material for vapor deposition is granular, powder, or a molded body obtained by press molding these. Material .

According to a third aspect of the present invention, the vapor deposition material according to the first aspect is vaporized by evaporating by a heating method, and the ratio of the number of atoms of silicon and oxygen (O / Si) is 1.50 to 1.90. It is the manufacturing method of the gas-barrier vapor deposition film characterized by forming on the base material .

The invention according to claim 4 of the present invention is the method for producing a gas barrier vapor deposition film according to claim 3 , wherein the heating method is an electron beam heating method.

The invention of claim 5 of the present invention is a heating type vapor deposition material in which silicon dioxide and zinc sulfide, or metallic silicon, silicon dioxide and zinc sulfide are mixed, and is a total of silicon and zinc sulfide. The ratio of the number of atoms to the number of oxygen atoms (O / (Si + ZnS)) is in the range of 0.75 to 1.75, the bulk density is in the range of 0.8 to 1.5 g / cm ³ , and Silicon is a gas barrier vapor deposition film in which a vapor deposition material containing at least 20% or more of a crystal structure is evaporated to form a vapor deposition film on a substrate, and the ratio of the number of atoms of silicon and oxygen (O / Si) is a gas barrier vapor-deposited film having 1.50 to 1.90 .

The invention according to claim 6 of the present invention is the gas barrier vapor-deposited film according to claim 5 , wherein the tensile strength is 3.0% or more.

  According to the vapor deposition material of the present invention, a splash phenomenon can be suppressed even when an electron beam heating vapor deposition method at a high output is used to improve productivity, and a gas barrier vapor deposition film having high gas barrier properties and tensile strength can be obtained. Can do.

It is sectional drawing explaining an example of the gas barrier vapor deposition film of this invention. It is typical explanatory drawing of the apparatus which manufactures an example of the gas barrier vapor deposition film of this invention.

Hereinafter, modes for carrying out the present invention will be described.
FIG. 1 is a cross-sectional view illustrating a gas barrier vapor deposition film of the present invention. The gas barrier vapor-deposited film is an inorganic oxide film 2 formed by vapor-depositing metal silicon (Si) and silicon oxide (SiOx) or a mixture of these with zinc sulfide (ZnS) on a polymer film substrate 1. Is provided by a vacuum deposition method. This is preferable from the viewpoint of gas barrier performance and uniformity.

  As a film forming means, a heating vapor deposition method using an electron beam, a laser beam, or the like is preferably used among the vacuum vapor deposition methods. Is effective in that it can be performed in a short time.

The silicon oxide (SiOx) is silicon dioxide (SiO ₂ ) containing at least 20% of a crystal structure. For this purpose, oxygen gas can be generated from silicon dioxide by an electron beam, and this oxygen gas can be reacted with metal silicon or zinc sulfide. Further, the inorganic oxide film 2 may be formed on both surfaces of the polymer film substrate 1, may be multilayered, or may be the inorganic oxide film 2 having different compositions on the front and back sides.

The polymer film substrate 1 is not particularly limited, and a known one can be used. For example, polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene naphthalate, polyethylene terephthalate, etc.), polyamide (nylon-6, nylon-66, etc.), polystyrene, ethylene vinyl alcohol, polyvinyl chloride, polyimide, polyvinyl alcohol , Polymer film bases such as polycarbonate, polyethersulfone, acrylic, and cellulose (triacetylcellulose, diacetylcellulose, etc.), but not particularly limited.

  It is preferable to use a transparent film as the polymer film substrate 1 because it is suitable for mass production. In addition, the thickness is not particularly limited, and is practically preferably in the range of 12 to 188 μm in consideration of workability such as vapor deposition processing for forming a gas barrier vapor deposition film.

  In general, the thickness of the inorganic oxide film 2 formed on the surface of the polymer film substrate 1 by the mixed vapor deposition material composed of evaporated metal silicon and silicon dioxide is desirably in the range of 5 to 300 nm. The value is appropriately selected.

  However, if the thickness is less than 5 nm, a uniform film may not be obtained or the film thickness may not be sufficient, and sufficient barrier performance may not be exhibited. In addition, when the film thickness exceeds 300 nm, the film cannot retain flexibility, and there is a possibility that the film may crack due to external factors such as bending and tension after the film formation.

  The mixed material composed of metal silicon, silicon oxide, and zinc sulfide used as a deposition material in the present invention is a specific ratio of the number of atoms of silicon and oxygen (O / Si), or the total of silicon and zinc sulfide. By controlling the ratio of the number of atoms to the number of oxygen atoms (O / (Si + ZnS)) and the bulk density, it is difficult to be destroyed by thermal shock caused by an electron beam, that is, thermal shock resistance Is improved and the splash phenomenon is suppressed.

  And, in vapor deposition by electron beam heating, by controlling the bulk density, by reducing the thermal conductivity so as not to become a dense structure, and by mixing silicon dioxide with low thermal conductivity, The occurrence of bumping due to a sudden temperature rise due to electron beam heating is suppressed, and the splash phenomenon is reduced.

  Also, when silicon dioxide is heated, oxygen gas is desorbed, and the heated metal silicon reacts without bumping because it is in the vicinity of oxygen gas generated from silicon dioxide, and becomes SiOx vapor. In addition, although vapor deposition with only zinc sulfide is difficult, this also reacts with oxygen gas desorbed from silicon dioxide to become ZnOy / ZnS vapor, thereby forming a SiOx / ZnOy / ZnS film on the polymer film substrate 1. Can be formed. Moreover, it is thought that the splash is suppressed because the molten silicon dioxide remains on the surface layer of the evaporation material.

Regarding the vapor deposition material in which the metal silicon and the silicon oxide of the present invention are mixed, the ratio of the number of oxygen atoms to silicon (O / Si) is preferably 1.00 to 2.00, and for a splashless process. 1.50 to 1.70 is more preferable. When the O / Si ratio is 1.00 or higher, pinholes and appearance defects due to splash occur, and when the O / Si ratio is 2.00 or higher, barrier degradation occurs due to approaching SiO ₂ .

Further, the bulk density of the mixed vapor deposition material is preferably 0.8 to 1.5 g / cm ³ , and more preferably 0.9 to 1.1 g / cm ³ . When the bulk density is 0.8 g / cm ³ or less, cracking and scattering of the vapor deposition material is likely to occur, and when the bulk density is 1.5 g / cm ³ or more, more energy is required to evaporate the material, and the rate decreases. To do.

  As the silicon oxide used here, it is desirable to use silicon dioxide having at least 20% X-ray crystal structure. For the measurement of the crystalline portion and the non-crystalline portion of silicon dioxide, each peak was separated using an X-ray diffraction apparatus (XRD), and the crystallinity was determined from the ratio of the integrated intensity. When silicon dioxide having a crystallinity of 20% or less, that is, a crystal structure of 20% or less is used, the rate barrier property is inferior.

  Furthermore, vapor deposition materials made of metal silicon and silicon oxide are easy to mix when using the same particle size, and the process of raising the temperature of the vapor deposition material is simplified by using powders of 1 μm to 100 μm. This is presumably because the silicon, which is a metal, is uniformly mixed with the vapor deposition material, so that the material is likely to be warmed and the electron beam is not easily defocused.

  Further, in the case of the evaporation material in which the metal silicon of the present invention is mixed with silicon oxide and zinc sulfide, the ratio of the total number of atoms of silicon and zinc sulfide to the number of oxygen atoms (O / (Si + ZnS)) is 0. 50 to 2.00 is desirable, and 0.75 to 1.75 is more preferred for a splashless process.

  When the deposition material O / (Si + ZnS) is 0.50 or less, silicon dioxide contained in the material is small, so that a melted portion is reduced on the surface of the material and splash occurs. Moreover, at 2.00 or more, rate barrier property deteriorates because zinc oxide decreases.

  Metal silicon may not be added, and a vapor deposition material in which two types of zinc sulfide and silicon dioxide are mixed may be used.

Furthermore, the bulk density of the mixed material for vapor deposition is desirably in the range of 0.8 to 1.5 g / cm ^{3. If} the bulk density is low, splash due to scattering tends to occur, and if the bulk density is too high, it remains on the material surface. The melt-type deposition material hinders evaporation and causes a decrease in deposition rate.

  The shape of the vapor deposition material of the present invention may be a molded body, a granule, or a powder, but the ratio of the number of atoms of silicon and oxygen (O / Si) or the total number of atoms of silicon and zinc sulfide Transparent gas barrier vapor deposition with high barrier properties without causing a splash phenomenon as compared with conventional vapor deposition materials by setting the ratio of the number of oxygen atoms (O / (Si + ZnS)) to a specific bulk density. A film can be obtained.

  FIG. 2 is a schematic explanatory view of an apparatus for producing an example of the gas barrier vapor deposition film of the present invention. Specifically, there is a film forming roll 3 in the vapor deposition chamber of an electron beam heating type vacuum vapor deposition apparatus, and the polymer film base material 1 is held on the film forming roll 3 to run. The evaporation material 5 is heated and evaporated from the lower crucible 6 to form the inorganic oxide film 2 on the surface of the polymer film substrate 1.

  The crucible 6 is installed on a vapor deposition material moving carriage 7, an electron beam 4 emitted from an electron gun (not shown) is irradiated from above the crucible 6, and the vapor deposition material 5 in the crucible 6 is irradiated. It is evaporated by heating. Further, the electron beam 4 is scanned or the evaporation material moving carriage 7 is moved so that the electron beam 4 is not irradiated only on the same position of the evaporation material 5.

  Specific examples of the present invention will be described below.

<Example 1>
The metal silicon used was a powder having a diameter of 50 μm or less of 95% or more, and the silicon dioxide containing a crystal structure containing 95% and a powder having a diameter of 50 μm or less was 95% or more. First, mixed vapor deposition material 5 made of metal silicon and silicon dioxide in which the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) was 1.50 was produced. This mixed vapor deposition material 5 was put into a crucible 6 and press-molded so that the bulk density was 1.0 g / cm ³ .

  An electron beam heating type vacuum deposition apparatus irradiates the mixed deposition material 5 with the electron beam 4 emitted from the electron gun and evaporates it, and adjusts the film forming roll speed so that the inorganic oxide film 2 becomes 30 nm. A film was formed on the film substrate 1.

<Example 2>
Zinc sulfide powder was added to the mixed vapor deposition material 5 produced in Example 1 so that the ratio of the total number of atoms of silicon and zinc sulfide to the number of oxygen atoms (O / (Si + ZnS)) was 0.75. . As the zinc sulfide powder, a powder having a diameter of 50 μm or less having a diameter of 95% or more was used, and this was put into the crucible 6 in the same manner as in Example 1 and the bulk density was adjusted to 1.0 g / cm ^3. A zinc oxide / silicon oxide composite film was formed on a polymer film by a beam heating type vapor deposition apparatus.

<Example 3>
The metal silicon powder and the zinc sulfide powder were mixed so that the ratio of the total number of atoms of silicon and zinc sulfide to the number of oxygen atoms was O / (Si + ZnS) = 1.20. This was put into the crucible 6 in the same manner as in Example 1 and the bulk density was adjusted to 1.0 g / cm ³ , and then similarly an inorganic oxide film composed of a zinc oxide / silicon oxide composite film by an electron beam heating type vapor deposition apparatus. 2 was formed on the polymer film substrate 1.

  Hereinafter, comparative examples of the present invention will be described.

<Comparative Example 1>
Using powdered silicon monoxide (SiO) of the material 5 for vapor deposition by the vacuum vapor deposition method, this was put into the crucible 6 in the same manner as in Example 1 and the bulk density was adjusted to 1.0 g / cm ^3. An inorganic oxide film 2 made of a silicon oxide film was formed on the polymer film substrate 1 by a beam heating type vapor deposition apparatus.

<Comparative example 2>
The same silicon and silicon dioxide as in Example 1 were used and mixed so that the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) was 1.00. This was put into the crucible 6 in the same manner as in Example 1 and the bulk density was adjusted to 1.0 g / cm ³ , and then the inorganic oxide film 2 made of a silicon oxide film was polymerized with an electron beam heating type vapor deposition apparatus. It was formed on the film substrate 1.

<Comparative Example 3>
The same silicon and silicon dioxide as in Example 1 were used and mixed so that the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) was 1.00. This was put into the crucible 6 in the same manner as in Example 1 and the bulk density was adjusted to 1.5 g / cm ³ , and then the inorganic oxide film 2 made of a silicon oxide film was similarly polymerized by an electron beam heating type vapor deposition apparatus. It was formed on the film substrate 1.

  For the gas barrier vapor deposited films of Examples 1 to 3 and Comparative Examples 1 to 3, the occurrence of splash was checked by the following method, and the water vapor transmission rate and the tensile strength were measured and evaluated. Further, the ratio of the number of atoms of silicon and oxygen (O / Si) in the deposited film evaporated and evaporated was measured. The results are summarized in Table 1.

  In the vapor deposition material in which silicon oxide and metallic silicon are mixed and (O / Si) is 1.50 to 1.70, (O / Si) of the vapor deposition film is 1.70 to 1.90, Even in the case of a deposition material having (O / (Si + ZnS)) of 0.75 to 1.75, in which silicon oxide and zinc sulfide or metal silicon, silicon oxide and zinc sulfide are mixed, a deposited film (O / Si) of 1.50 to 1.90.

<Splash>
The gas barrier vapor-deposited films of Examples 1 to 3 and Comparative Examples 1 to 3 were visually examined for the presence of pinholes and foreign matters due to splash. The case where there was no pinhole or foreign matter due to splash was marked as ◯, the number of pinholes or foreign matter due to splash was 1 to 10, and the case where there were 11 or more pinholes or foreign matter due to splash was marked as x.

<Water vapor transmission rate>
The water vapor permeability of the gas barrier vapor deposition films of Examples 1 to 3 and Comparative Examples 1 to 3 was measured using a water vapor permeability measuring device (MOCON PERMATRAN 3/21 manufactured by Modern Control) in an atmosphere of 40 ° C. and 90% RH. It was measured.

<Tensile strength>
When the gas barrier vapor-deposited films of Examples 1 to 3 and Comparative Examples 1 to 3 were pulled with a tensile tester at a tensile rate of 6 μm / sec, the vapor-deposited film was observed with an optical microscope. The elongation was measured as tensile strength [%].

<O / Si ratio of the deposited film>
The ratio of the number of atoms of silicon and oxygen (O / Si) in the vapor deposited films of the gas barrier vapor deposited films of Examples 1 to 3 and Comparative Examples 1 to 3 was measured by the following method.

  Sampling method: A film having a size of 10 mm × 10 mm was cut out from the gas barrier vapor-deposited film of each example to obtain a sample for measurement.

  Measuring instrument and measuring method: The composition analysis of the deposited film was performed with an X-ray photoelectron spectrometer (ESCA). The composition analysis was repeated three or more times in the depth direction of the deposited film with argon ions, the average was obtained, and the O / Si ratio was calculated.

<Comparison result>
From Table 1, the occurrence of splash was confirmed from Comparative Examples 1, 2, and 3, whereas no splash occurred from the other Examples 1, 2, and 3. This means that the splash is suppressed by the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) in the deposition material 5.

Furthermore, the water vapor barrier property is remarkably improved by adding zinc sulfide for vapor deposition. A vapor deposition film made of a mixed vapor deposition material of metal silicon and silicon dioxide, or a vapor deposition film made of a vapor deposition material of silicon monoxide has a water vapor transmission rate of about ^{2 to 3} g / m ² · day, while mixing with zinc sulfide. A vapor deposition film made of a vapor deposition material is a composite film of SiOx and ZnOy, which has a water vapor transmission rate of less than 1 g / m ² · day, and is considered to have improved water vapor barrier properties.

  Also, in terms of tensile strength, there is a correlation with the ratio of the number of oxygen atoms and the number of silicon atoms (O / Si) in the deposited film, and when the O / Si = 1.70 or more, the initial crack generation in the deposited film film Becomes 3% or more. In Examples 1 to 3, since the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) exceeded 1.70, the tensile strength was 3% or more. On the other hand, in Comparative Examples 1 to 3, the ratio of the number of oxygen atoms to the number of silicon atoms (O / Si) is 1.70 or less, and sufficient tensile strength cannot be obtained, resulting in a tensile strength of 3% or less. It was.

By providing transparent gas barrier films with high productivity and low gas barrier performance at low cost, it can be widely applied to the fields of components that need to block oxygen and water vapor in the packaging field of food, daily necessities, and medical products, or in the relative packaging field. .

DESCRIPTION OF SYMBOLS 1 ... Polymer film base material 2 ... Inorganic oxide film 3 ... Film-forming roll 4 ... Electron beam 5 ... Deposition material 6 ... Crucible 7 ... Deposition material movement cart

Claims (6)

The zinc sulfide and silicon dioxide or, a zinc sulfide metal silicon and silicon dioxide, a vapor deposition material for heating system which is a mixture of silicon and the total number of atoms of zinc sulfide, the number of oxygen atoms The ratio (O / (Si + ZnS)) is 0.75 to 1.75, the bulk density is in the range of 0.8 to 1.5 g / cm ³ , and silicon dioxide contains at least 20% or more of the crystal structure deposition material characterized in that out. 2. The vapor deposition material according to claim 1 , wherein a shape of the vapor deposition material is granular, powdery, or a molded body obtained by press molding these. The evaporation material according to claim 1 is evaporated by a heating method and evaporated, and formed on a substrate so that the ratio of the number of atoms of silicon and oxygen (O / Si) is 1.50 to 1.90. A process for producing a gas barrier vapor-deposited film characterized by the above . The method for producing a gas barrier vapor-deposited film according to claim 3 , wherein the heating method is an electron beam heating method . A heating type vapor deposition material in which silicon dioxide and zinc sulfide, or metal silicon, silicon dioxide and zinc sulfide are mixed, wherein the total number of atoms of silicon and zinc sulfide and the number of oxygen atoms are The ratio (O / (Si + ZnS)) is 0.75 to 1.75, and the bulk density is 0.8 to 1.5 g / cm. ³ And silicon dioxide is a gas barrier vapor deposition film in which a vapor deposition material containing at least 20% or more of a crystal structure is evaporated to form a vapor deposition film on a substrate, A gas barrier vapor-deposition film having a ratio of oxygen atoms (O / Si) of 1.50 to 1.90. The gas barrier vapor-deposited film according to claim 5 , wherein the tensile strength is 3.0% or more.