JPS5949359B2 - metallized paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to metallized paper for decorative purposes, particularly for gold and silver threads.

Traditionally, this type of paper uses strong and dense washi paper made from korazo, mitsumata, and ganbi wood as the main raw materials.

When using Japanese paper as the base paper, metallized paper goes through the following processing steps.

That is, a coating process for forming a sealing layer 2 using polyvinyl alcohol on the base paper 1 shown in the drawing, a coating process for forming an undercoat layer 3 using varnish such as epoxy resin, and a coating process for forming a metal vapor deposition layer 4 such as aluminum, gold, or silver. The film consists of a vapor deposition step, and finally a coating step, in which a protective layer 5 is formed using a lacquer such as nitrocellulose. The reason for creating the sealing layer 2 is to prevent the varnish undercoat liquid from penetrating into the base paper 1, and the undercoat layer 3 is a layer for receiving metal vapor deposition.

When the varnish penetrates into the base paper 1, not only does the gloss of the metal-deposited surface decrease, but the base paper itself becomes brittle and loses its toughness.
When creating the sealing layer 2, it is necessary for the base paper to be dense and have shielding properties in order to complete the sealing, which is one of the reasons why Japanese paper is often used as this type of base paper. It is one. The metallized paper is slit with a micro slitter to a width of 11 to 41, for example, and used as a flat foil or as gold thread or silver thread for textiles by winding it spirally around a suitable core thread.

As mentioned above, Japanese paper has traditionally been used for this type of paper, but it is very dense and hard to the touch.
Easy to crease.

Furthermore, since natural raw materials are used, there are many small pieces of waste such as wood chips. For this reason, it has the disadvantage that it is easily cut when slitting with the above-mentioned micro slitter and when processing into yarn. Another disadvantage is that it has become very expensive due to the labor shortage of raw materials in recent years. In order to eliminate the above drawbacks, attempts have been made to replace Japanese paper with vinylon paper, which has the following characteristics: it is strong enough, is flexible, durable, and is inexpensive. However, they cannot be used as base paper for metal deposition because they lack density and shielding properties.

The present inventors focused on the advantages of this vinylon-based paper that are difficult to throw away, and as a result of various studies to create something superior to conventional metal-metalized paper that uses Japanese paper as a base paper, the present invention was completed. It is something. That is, the present invention has an air permeability according to JIS-L-1079 of 20 CC/1, which contains water-soluble borates and is mainly made of vinylon fibers of 1 denier or less.
Basis weight 1 adjusted by calendaring below Cd formula
A metal vapor deposited layer in which a sealing layer made of polypynyl alcohol is provided on a base paper of 5 to 50 f1/i, and a subbing layer, a metal vapor deposited layer, and a protective layer are sequentially provided on the sealing layer. It is something. Pinilon fiber is a highly hydrophilic fiber and is very easy to handle as a raw material for papermaking.

Furthermore, the base paper obtained is extremely strong, with particularly excellent tensile strength and folding strength, and is also water resistant, making it the most preferred material for gold, silver, and other threads. The reason why the thickness of the fibers used is limited to 1 denier or less is that shielding properties are required during processing, and thick fibers exceeding 1 denier have a basis weight of 15 to 50 f! In this type of thin base paper (A), the air permeability is too high, and the sealing layer 2 cannot be completely formed. Even if the base paper uses fibers of 1 denier or less, the air permeability of Japanese paper is 0.5 to 1.0 CC/
It is far from the Cil-type.

Therefore, if left as is, the coating of polyvinyl alcohol will cause strike-through, and not only will a complete sealing layer 2 not be formed, but the base paper 1 will become hard and brittle, making it unusable. As a result of various studies, we found that by incorporating water-soluble borates such as borax into the base paper and adjusting the air permeability to 20cc/Cd-type or less, we were able to completely prevent bleed-through during the sealing process. I discovered what I could do.

This takes advantage of the fact that water-soluble borates have the ability to instantaneously gel polypinyl alcohol, and unlike ordinary paper, this type of pinylon-based paper has extremely high air permeability. There are no examples of this being applied.

There are some cases where boric acid is used as an agent to prevent the penetration of polypinyl alcohol into porous materials, but boric acid has no effect at all in the present invention, and is not a water-soluble borate such as borax. I can't reach my goal. Even if the base paper is mainly composed of vinylon fibers containing water-soluble borates, if the air permeability exceeds the formula 20CC/Cd-, it will be too porous and the purpose cannot be fully achieved.

The air permeability can be adjusted using known equipment such as a machine calender of a paper machine or a supercalender.

In that case, it is most preferable to carry out the treatment after containing the water-soluble borates, but first perform calendering to achieve an air permeability of 20CvCit・SecJ. ). Water-soluble borates may be added after the adjustment. When polyvinyl alcohol is applied to the base paper of the present invention, the polyvinyl alcohol immediately gels on the surface layer due to the action of water-soluble borates in the base paper, so that a uniform film is formed on the surface of the base paper. , and exhibits sufficient shielding properties as the sealing layer 2.

Next, when an epoxy varnish is applied thereon, a uniform undercoat layer 3 is formed on the sealing layer 2 to prevent penetration of the varnish liquid. By further applying metal vapor deposition and finally applying a protective layer 5 of nitrocellulose or the like, metal vapor deposited paper with a very elegant luster comparable to that of Japanese paper can be obtained. In the present invention, air permeability refers to JIS-L-1079
This refers to the value measured using a Frazier type tester specified in

In addition, water-soluble borates refer to various borates at 20°C.
This refers to borates having a solubility in water of 1f1/100WLt or more, and preferred examples include sodium borate, ammonium borate, and potassium borate.

The amount of these necessary in the sheet varies slightly depending on the type of salt and the concentration of polypinyl alcohol used in the sealing layer, but taking sodium borate as an example, if it contains 0.59/I, The purpose can be sufficiently achieved when the concentration of the polypynyl alcohol aqueous solution is 5% by weight or more. In this way, it became possible to create an excellent metal-metalized paper made from a base paper mainly made of vinylon fibers, which is much more flexible than Japanese paper.

The amounts of polyvinyl alcohol applied as a sealing layer and epoxy-based Kunis applied as an undercoat layer are both 2 to 5 fI/I in terms of solid content.

The present invention will be explained below with reference to examples, but the present invention is not limited thereto.

Example 1 VPB053X3 [Pinilon fiber, 0.5 denier, 3
u length, manufactured by Kuraray Co., Ltd.] 75 parts by weight, VPBLO5-1
Disperse 25 parts by weight of [polypynyl alcohol-based fibrous binder manufactured by Kuraray Co., Ltd.] to a concentration of 0.1%, and use a polyethylene glycol-based papermaking adhesive to obtain a basis weight of 18f! / A vinylon base paper was made.

The air permeability of this base paper was 33 cc/Cd-Sec.
The base paper was then calendered to an air permeability of 15 CC/
(:d-SeC. This is referred to as base paper A. Base paper A is impregnated with a 4% by weight aqueous solution of borax, and 0.69/Trl (solid content) of borax is contained in the base paper. Base paper B used in the present invention was obtained. Polyvinyl alcohol (concentration 10% by weight, viscosity 1200 CPS) with a degree of polymerization of 20000 was added to base paper A for comparison and base paper B used in the present invention at 39/I ( However, on base paper A for comparison, the polyvinyl alcohol showed through over the entire surface, and the sheets that were obtained had many troubles during the coating process and were also unsuitable for subsequent processing. .

On the other hand, base paper B used in the present invention had no polyvinyl alcohol bleed through and caused no trouble during the coating operation.

The obtained sheet had a uniformly formed semi-glossy thin sealing layer and was suitable for subsequent processing. That is, although 5 g/i (solid content) of epoxy varnish was applied, the penetration of the varnish into the base paper was completely suppressed, and a film ideal as an undercoat layer was formed. Next, silver was vapor-deposited thereon, and a layer of nitrocellulose was then applied as a protective layer to complete silver-deposited paper. This metallized paper had a very elegant texture and luster, and was suitable as metallized paper for silver thread. The main physical properties are shown in Table 1.

Example 2 The base paper immediately after papermaking obtained in Example 1 (air permeability 33cc/Cd
-Sec), ammonium borate [(NH4)2B1
0016.8H20] was impregnated with a 7% by weight aqueous solution,
Ammonium borate was contained at 1.0 g/i (solid content).

This is called base paper C.

This air permeability was 34 CC/Cd·Sec. Base paper C
Super calendered the air permeability to 17cc/d-S.
ec, and base paper D used in the present invention was completed. Base paper C for comparison and base paper D used in the present invention had a polymerization degree of 17.
00 polypynyl alcohol (concentration 12% by weight, viscosity 1300CPS) was applied at a solid content of 3 g/day, but on base paper C for comparison, the polypynyl alcohol bleed through in some places and the sealing layer was incomplete. Ta.

On the other hand, base paper D used in the present invention had no strike-through and no trouble occurred during the coating operation. The obtained sheet had a uniform semi-glossy sealing layer and was suitable for subsequent processing.

[Brief explanation of drawings]

The drawing is a sectional view of a main part of metallized paper. 1...My paper, 2...Sealing layer, 3...
...Undercoat layer, 4...Metal deposition layer, 5...
...protective layer.

Claims (1)

[Claims] 1 Contains water-soluble borates, is mainly composed of vinylon fibers of 1 denier or less, and has an air permeability according to JIS-L-1079 adjusted to 20/cm^2・sec or less by calendering, and has a basis weight A sealing layer made of polyvinyl alcohol is provided on a base paper of 15 to 50 g/m^2,
A metal-deposited paper in which an undercoat layer, a metal-deposited layer, and a protective layer are sequentially provided on the sealing layer.