JPS6040382B2 - composite film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a composite film with improved surface hardness, abrasion resistance, scratch resistance, abrasion resistance, and flatness.

As is well known, the film Motomura, which is made of a flexible organic polymer solid, has excellent characteristics such as light weight, impact resistance, transparency, and processability, so it is used in a wide range of applications. However, the surface of the base material is soft and easily scratched, which reduces transparency and aesthetic appearance, so there is a strong desire for improved wear resistance in practical use.

As a means to improve these drawbacks, glass,
Properties such as mechanical and chemical properties of the surface have been improved by vapor deposition or coating with metals or high hardness substances.

A method of coating melamine resin as a hardening material has already been proposed.

For example, a composition consisting of etherified methylolmelamine, nitrified wire, and polyalkylene glycol; a composition consisting of etherified methylolmelamine, nitrated cotton, tetraalkyl silicate, and (poly)alkylene glycol; methyletherified methylolmelamine, Compositions made of (poly)alkylene glycol and hydrolyzed condensates of silicon compounds are known, and attempts have been made to apply these coatings to the surface of plastic plates and then heat cure them. However, when the above composition is coated on a substrate made of a flexible organic polymer solid, curls and cracks occur due to changes in the coating film such as volume shrinkage during curing, so it cannot be applied to flexible substrates. It was difficult to put it into practical use.

They also have shortcomings such as short pot life and long curing times.

. The present invention solves the above problems and provides a composite film that simultaneously satisfies excellent surface hardness, abrasion resistance, scratch resistance, abrasion resistance, coagulability, and flatness.

It is hard to scratch, does not curl or crack, and can be supplied continuously if necessary, making it extremely easy to work with.
Moreover, it is chemically, thermally, and optically excellent, so it can be effectively applied to various uses. An example of the application is as follows.

Magnetic tape base material; Protection of magnetic cards, magnetic disks, video disks, documents for overhead projectors, etc.; Protection of imaged films such as various silver salts, diazonium, electrophotography, etc.; Microfilm jacket; Optical mask; Copying machine Master belt or photosensitive drum;
Electrostatic recording material; For building materials and wheels (glass lamination, synthetic resin plate lamination, steel plate lamination, etc.); Decorative use (displays, stamping foils, etc.); Miscellaneous goods (labels, writing base materials, adhesive tapes, etc.) ); Packaging; Printing/plate making; Protection of metals or metal compounds; Capacitors; Flame retardant, non-combustible materials, etc. In the present invention, 10 to 40 parts by weight of colloidal silica and 0 to 40 parts by weight of an epoxy compound are added to at least one surface of a substrate made of a flexible organic polymer solid, based on 100 parts by weight of methylolated melamine or alkyl etherified methylolmelamine. The composite film is coated with a composition comprising 25 parts by weight of a curing catalyst and/or a curing agent.

Preferred organic polymers constituting the base material include, for example, polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2,6-naphthalene dicarboxylate, polyolefins such as polypropylene and polyethylene, and polyamides such as so-called nylon 6 and nylon 12. , polyimide having a five-membered ring imide bond in the polymer main chain, cellulose derivatives such as cellulose ester, polystyrene, polycarbonate, acrylic ester copolymer, methacrylic ester copolymer, polyvinyl chloride, polyether, polyester ether, These include organometallic polymers crosslinked with metal ions by copolymers with maleic acid or itaconic acid, and include, but are not necessarily limited to, copolymers or blends thereof.

Although these polymer films can be used in an unstretched state, stretching, particularly biaxial stretching, improves mechanical properties, thermal properties, optical properties, and dimensional stability, which is preferable.

Among them, polyethylene terephthalate film is particularly preferably used. Furthermore, these polymer films may be subjected to surface treatment (e.g., corona discharge treatment, corona discharge treatment in an inert gas or nonflammable gas, flame treatment, reverse sputtering treatment, etc.) to improve adhesion as necessary.
It is possible to perform a treatment with a charged flame, etc.) or to provide a surface damage layer such as a primer.

The thickness of the base film layer is not particularly limited, but for example,
A range of 6v to 500m is desirable.

When it becomes thinner, workability becomes inferior. Usually 9 Buddha ~ 200
can be preferably used. The methylolated melamine or alkyl etherified methylolmelamine of the present invention is
It is methylolated melamine or an alkyl etherified product of methylolated melamine represented by the following general formula.

It may also be a condensate having the following constituent units. These can be used singly or as a mixture of two or more ropes. (However, R,, R2 is one CQOH per day.
, -CH2 -R3 (R3 is an alkyl group having from i to 4 carbon atoms).

Each R,, R2 may be the same or different. ) From wear resistance, scratch resistance, and abrasion resistance,
Preferred are trimethylol- or higher-methylolated melamine, or methylolmelamine in which some or all of these methylol groups are alkyl etherified. Most preferred is methyletherified methylolmelamine.
The colloidal silica of the present invention has a particle size of 5 to 100.
A commercially available one selected from colloidal solutions prepared by dispersing silicic anhydride in water, an alcoholic solvent, dimethylformamide, etc., manufactured by a well-known method, can be used.

Epoxy compounds are widely used in paints, castings, etc., such as polyolefin epoxy resins synthesized by peroxidation methods, cyclobentadiene oxide, hexahydrophthalic acid, and epichlorohydrin. Polyglycidyl esters obtained from polyhydric phenols such as bisphenol A, catechol, and resorcinol, or (poly)ethylene glycol, (poly)propylene glycol, neobentyl glycol, glycerin, trimethylolpropane, bentaerythritol,
Polyglycidyl ethers obtained from polyhydric alcohols such as diglycerol and sorbitol and epichlorohydrin, alicyclic epoxy resins, epoxidized vegetable oils, and epoxies obtained from borac-type phenolic resins and epichlorohydrin. Novolac resin, epoxy resin obtained from phenolphthalein and epichlorohydrin, and also
Polymers of glycidyl methacrylate and acrylic monomers such as methyl methacrylate or styrene, y-glycidoxypropyltrimethoxysilane and y-glycidoxypropyltrimethoxysilane
Examples include epoxysilane-containing compounds such as glycidoxypropylmethyljethoxysilane.

Next, the curing catalyst and/or curing agent may be an inorganic or organic acid such as hydrochloric acid, phosphoric acid, sulfuric acid, p-toluenesulfonic acid, oxalic acid, maleic acid, acetic acid, nitric acid, or these acidic substances. The salts are usually preferably used.

In addition, organic carboxylic acid metal salts, thiocyanate metal salts, acetylacetone metal chelate compounds, organic amine salts, organic tin compounds, etc. can also be used. The above composition can be used without adding a new solvent, but a solvent can be added depending on the purpose.

Solvents include 'a} methanol, ethanol, n- or improvil alcohol, n- or iso, solvent
-Alcohols such as butyl alcohol, aromatic hydrocarbons such as 'b-toluene and xylene, {c) water alone or in combination, and if necessary, ketones, esters, and ethers can be used. , cellosolve-based solvents, and halogenated hydrocarbon-based solvents may be used alone or in combination.

In order to improve the flow during application and the smoothness of the coating film, it is possible to use a surfactant in the composition of the present invention, and if necessary, adhesion promoters, pH adjusters,
Additives such as plasticizers, stabilizers, antioxidants, ultraviolet absorbers, lubricants, thickeners, antifoaming agents, and colorants may also be used in combination. It is also permissible to add and blend other organic compounds and organic polymer resins to the extent that the properties of the composition can be maintained. The blending ratio of the composition of the present invention is 10 to 4 parts by weight of colloidal silica to 10 parts by weight of melamine.
0 parts by weight, preferably 30 to 250 parts by weight, 0 to 25 parts by weight, preferably 3 to 20 parts by weight of the epoxy compound, 0.01 to 3 parts by weight of curing catalyst and/or curing agent, preferably 0 .5 to 1 part by weight.

If the amount of colloidal silica exceeds the above range, the flexibility will deteriorate and defects such as cracks will occur, and the risk of deterioration of appearance due to clouding of the coating film and poor film forming properties will increase. Although the epoxy compound is not necessarily necessary when the base layer is thick (for example, 75 peaks or more), it is an important compounding agent for maintaining beard properties and flatness. When the amount exceeds 25 parts by weight, hardness and wear resistance decrease.

If the amount of curing catalyst/curing agent added is less than 0.01 part by weight, curing will be insufficient or it will take a long time to cure, while if it exceeds 3 parts by weight, the coating film or resin may become transparent. This causes defects such as decreased potency and pot life. The solid coating thickness of the composition of the present invention is not particularly limited, but is preferably in the range of, for example, 0.5 mm to 30 mm.

If the thickness is too thin, the abrasion resistance will not be sufficient, and if it exceeds 30 mm, the curing time will become longer, flatness will decrease, and cracks will occur, which is not preferable. The means for applying such a composition to the substrate include brush coating, dipping coating, knife coating, roll coating, spray coating, flow coating, and rotation coating (
A commonly used coating method such as spinner, wheller, etc. can be easily used. It is also possible to form a composite film by applying it before or after stretching during the film manufacturing process.

Suitable modifications and variations are within the scope of the invention.

For example, a thin metal layer, a colored layer, or even a recording layer may be provided between the base material and the hardening layer, or pigments, dyes, fillers, and inorganic fine particles may be added to the composition of the present invention. Good too.
A preferred combination of the composition of the present invention and the base film is:
This is a case where a composition consisting of methylenalized methylolmelamine, colloidal silica, an epoxy compound, and an acidic curing catalyst is applied to a polyester film.

When the base material becomes thin and a higher degree of flexibility is required, it is desirable to use an alicyclic epoxy compound that has good compatibility with the melamine resin as the epoxy compound. The composite film obtained in the above manner has excellent hardness, particularly abrasion resistance and scratch resistance, and is hardly scratched even when rubbed with hard materials such as steel wool, and is not easily damaged during processing or use. Since there is no deterioration in appearance due to scratches, durability and commercial value are significantly improved.

Furthermore, in addition to the above-mentioned characteristics, it has the following effects that have not been found in practical use in conventional flexible substrates.

■ It has flexibility and maintains the properties of plastic film such as excellent flatness, mechanical properties, and chemical properties.

■ No cracks occur due to bending or deflection of the base material.
There is no deterioration in appearance.

■ Good transparency.

■ Can be manufactured and used continuously, increasing productivity,
Work efficiency is improved, and significant labor and cost reductions are possible.

■ Has a stain-preventing effect.

Examples will be described below, but the invention should not be limited to these.

Note that parts and percentages in the examples are based on weight. Example 1 After corona discharge treatment on one side of a biaxially stretched polyethylene terephthalate film (“Lumirror” manufactured by Toray ■) with a thickness of 75 mm, methylolated melamine (“Nicalac” MW12 manufactured by Sanwa Chemical ■, 70% solution) was applied to 143 mm. Approximately 20 per portion
333 parts of a methanol dispersion of colloidal silica ("Methanol Silica Sol" manufactured by Nissan Chemical Industries, Ltd.) having a particle size of Sj0230% of r, 333 parts of a dicyclobentadiene dioxide alicyclic epoxy resin (such as " 100 parts of Zn(N03), 203 parts of Zn(N03) spots, and 424 parts of a 2/1/1 mixture of inpropyl alcohol/n-butyl alcohol/toluene as a solvent. So that the number is 3,
Apply using a roll coater and dry for 2 minutes at 15,000.
After curing, it was continuously rolled up.

It had excellent workability and good flatness and transparency. The performance of the composite film is shown in Table 1. The test method is as follows.

(The same applies to the following Examples and Comparative Examples). mountain exterior Visually inspect for optical non-uniformities and other defects.

[2- Rub with wear-resistant steel wool #0000 and check for scratch resistance.

Judgment was made as follows. A: No scratches even if rubbed strongly.

B: If it is rubbed quite strongly, it will be slightly scratched.

C: Even weak friction causes scratches.

[3] Adhesive strength: Strongly paste cellophane adhesive tape on the applied surface and heat it at 180o
Peel off sharply in the direction.

Judgment was made as follows. ○: The coating film does not peel off at all.

△: Peeling area of the paint film is less than 50% ×: Peeling area of the paint film is 50% or more {4) Flexible bending test) Composite films are wound around various cylinders with different diameters with the paint surface facing outward. It is expressed as the diameter when cracks occur in the paint film.

Practically speaking, a value of 1 or less is desirable. Comparative Example 1 In Example 1, 30 parts of dicyclobentajesodioxide alicyclic epoxy resin (for example, "Chissonox" manufactured by Chisso ■) was used as the epoxy compound, and inpropyl alcohol/n-butyl alcohol was used as the solvent. / toluene = 2/1/1 mixture 89 Ankaribe' The composite film obtained by coating, drying and curing in accordance with Example 1 using a paint containing a modified additive formulation had no flatness or transparency. Good, but poor abrasion resistance, steel wool #00
00, scratches occurred even with weak friction.

The performance of the composite film is shown in Table-1. Comparative Example 2 In Example 1, the blending amount of a methanol dispersion of colloidal silica ("Methanol Silica Sol" manufactured by Nissan Chemical Industries, Ltd.) having 30% of SiO2 with a particle size of about 20 was increased as the colloidal silica component to obtain a solution of 150. A composite filter obtained by applying, drying and curing the coating material containing Ikarito in accordance with Example 1 had good flatness, but the coating film became cloudy.

Also, minute cracks occurred during drying and curing. The performance of the composite film is shown in Table-1. Example 2 One side of a 100-thick biaxially stretched polyethylene terephthalate film (“Lumira” manufactured by Toray Industries, Ltd.) was subjected to corona discharge treatment, and then methylolized melamine (“Nikalac” M manufactured by Sanwa Chemical ■) was treated with corona discharge.
W12, 70% solution) 143 parts of S with a particle size of about 20 1/2
Methanol dispersion of colloidal silica having i0230% (“Methanol Silica Sol” manufactured by Nissan Chemical Industries, Ltd.) 3
The solid coating thickness was It was coated using a roll coater so that it had a coating of 3 coats, dried and cured at 150 oo for 2 minutes, and then continuously rolled up.

It had excellent workability and good flatness, transparency, and abrasion resistance. In addition, in terms of maneuverability (bending test), Example 1
Although the result was slightly inferior to that of the composite film, there was no problem in practical use. The performance of the composite film is shown in Table-1. Example
3 In Example 1, when a polycarbonate film having a thickness of 100 mm and provided with a primer layer in advance was used as the base material, similar results were obtained.

Example 4 After corona discharge treatment on one side of a biaxially stretched polyethylene terephthalate film (“Lumirror” manufactured by Toray ■) with a thickness of 50 mm, a 70% solution of methylolated melamine (“Nicalac” manufactured by Sanwa Chemical ■ MW12) was applied. ) 143 parts of a methanol dispersion of colloidal silica having a particle size of about 20 mm and containing 30% of SiO2 ("Methanol Silica Sol" manufactured by Nissan Chemical Industries, Ltd.), 333 parts of a bisphenol A glycidyl ether poxy compound (Shell Chemical Co., Ltd.) A paint containing 5 parts of "Epicote" 828) manufactured by ■, 203 parts of Zn(N03)2, and a 2/1/1 mixture of isopropyl alcohol/n-butyl alcohol/toluene 202 as a solvent was added. The coating was applied using a roll coater so that the solid coating thickness was 3 mm, dried and cured at 15,000 ℃ for 2 minutes, and then continuously wound up.

Claims (1)

[Claims] 1. 10 to 400 parts by weight of colloidal silica and 0 to 400 parts by weight of an epoxy compound per 100 parts by weight of methylolated melamine or alkyl etherified methylolmelamine on at least one side of a substrate made of a flexible organic polymer solid.
A composite film coated with a composition comprising 250 parts by weight of a curing catalyst and/or a curing agent.