JPS63142035A - Film for masking type - Google Patents

Abstract

PURPOSE:To obtain the titled film providing a masking film free from deterioration an shrinkage by heat because of excellent heat resistance and flexibility and extremely low heat shrinkability, comprising a polyurethane (meth)acrylate resin having a specific composition. CONSTITUTION:First, (A) a polyester or polyether containing a terminal OH group and plural active hydrogens is reacted with (B) an unsaturated polyether selected from a polyester or polyether containing OH group on one end and (meth)acryloyl on the other and a polyether glycol containing (meth)acryloyl on the side chain and (C) (carbodiimide modified) diphenylmethane diisocyanate or diphenylmetahne structure- containing polyisocyanate to give polyurethane (meth)acrylate resin. Then the resin and optionally a photosensitizer and/or a heat sensitizer are used to give the aimed film.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a masking tape film used for painting work, and more specifically, it has excellent heat resistance and flexibility, and is easily heat-shrinkable. It relates to a masking tape film with a very small fl.

[Prior Art] Traditionally, Japanese paper, crepe paper, polyester film, vinyl chloride film, etc. have been used as base materials for masking tapes used in painting operations. Due to practical requirements, the base material of this masking tape must have excellent heat resistance and flexibility, and furthermore, must have a low thermal shrinkage rate. However, no conventional base material has been found that satisfies all of these characteristics.

That is, among conventional base materials, Japanese paper generally has low heat resistance and can only be used at room temperature, while crepe paper has heat resistance up to about 180 degrees Celsius, but
Because the material is wrinkled, when the masking tape is removed after painting, the boundary between the painted area and the masked area (
There is a problem that the parting line (parting line) does not form a straight line (poor parting property).

Compared to Japanese paper or crepe paper, synthetic resin films are more practical as base materials for masking tapes.For example, polyester films shrink slightly even when heated at 180°C for 30 minutes. , and the parting performance is also good. However, this polyester film has poor flexibility, so if the painted surface is curved or uneven, the masking tape cannot be completely adhered to the area to be masked. As a result, coating defects occur. Also, from the point of view of flexibility alone, vinyl chloride film is superior, but in the case of vinyl chloride film, the heat shrinkage rate is extremely large, 1, for example, t60'.
Even if heated at c for 30 minutes, the area shrinks by about 10%, making it unsuitable for practical use.

[Problems to be Solved by the Invention] Among the various materials used as base materials for conventional masking tapes, there are materials that have satisfactory heat resistance, flexibility, and heat shrinkage resistance. Because there is nothing,
There is a problem that masking properties such as parting properties during painting are insufficient.

Therefore, it is an object of the present invention to solve the above problems and provide a film that can be used as a base material for masking tapes and has excellent masking properties.

[Means for Solving the Problems] The present inventors have discovered that a film obtained using polyurethane (meth)acrylate resin as a main constituent material has excellent heat resistance and flexibility, and is non-stretchable and non-directional. The present invention was completed by focusing on the fact that the heat loss rate is extremely low due to the properties of the material.

That is, the film for masking tape of the present invention +1
(A) (a) A polyester or polyether that has a hydroxyl group at one end and at least two or more active hydrogens in one molecule; (b) A polyester or polyether that has a hydroxyl group at one end and the other at least one unsaturated polyether selected from the group consisting of polyester or polyether having a (meth)acryloyl group at the end thereof and polyether glycol having a (meth)acryloyl group in the side chain; and (c) diphenylmethane diisocyanate, carbodiimide. At least one member selected from modified diphenylmethane diisocyanate-1 and a polyisocyanate having a diphenylmethane structure,
A polyurethane (meth)acrylate resin which is a reaction product of (B) and (B) a photosensitizer and/or a heat sensitizer as necessary are used as constituent materials.

Component (A), which is a constituent material of the film of the present invention, can be produced using the following components (a) to (c) as raw materials. Each component (a) to (c) will be explained below.

Component (a), which is a raw material for producing component (A), is a polyester or polyether that has a hydroxyl group at the end and at least two active hydrogen atoms in one molecule.

Polyester, which is one of the components (a), is a chain polymer with an average molecular weight of 400 to 2.000. Such polyesters can usually be produced from aliphatic dihydric alcohols each having 2 to 10 carbon atoms, preferably 2 to 6 carbon atoms, and a dihydric carboxylic acid.

Examples of dihydric alcohols include methylene glycol, ethylene glycol, 1,4-butanediol, 1
．． 3-butanediol, 2,3-butanediol, l,
Examples of divalent carboxylic acids include 5-bentanediol, 1.8-octanediol, and 1.10-decanediol, and polyethers other than these. glutaric acid,
Mention may be made of adipine acid, pimelic acid, sperine acid, azelaic acid, sebacic acid, phthalic acid, maleic acid and itacone ugly.

Such a polyester can be produced, for example, by combining the above-mentioned divalent alcohol and divalent carboxylic acid in a nitrogen atmosphere without a solvent, using a catalyst such as an alkali metal or alkaline earth metal oxide as necessary.

It can be obtained by heating at 140 to 220°C for 2 to 6 hours to carry out polymerization.

The polyether, which is one of the components (a), has the following formula; )(
O-E (cH2)-0)-H (in the formula, 1m is 2 to 6 years
represents an integer of n, where n is an integer determined according to the molecular weight). It is a chain polymer with an average molecular weight of 400 to 2.000.

Component (b), which is the raw material for producing component (A), has a hydroxyl group at one end and (
At least one unsaturated polyether selected from the group consisting of polyester or polyether having a meth)acryloyl group and polyether glycol having a (meth)acryloyl group in the side chain.

Among the components (b), polyester or polyether has the following formula; % formula % or the following formula; -0
~H (in the formula, R represents a hydrogen atom or a methyl group; both m and m represent an integer of 2 to 1O; n represents an integer of 1 to 10), or the following formula; % formula % or the following formula; CH2=C-0CO-(cH2)20-H(cH2)4
-0■(cH2)! -〇) iH (in the formula, R represents a hydrogen atom or a methyl group; p represents 2 or 4; q is 2 to 50
(representing an integer of ).

Such a polyester is prepared by adding at least an equivalent mole of glycidyl (meth)acrylate to a polyester having hydroxyl groups at both ends, for example, and then heating the mixture at 80 to 90°C for 1 to 2 hours in the presence of a polymerization initiator to carry out one reaction. It can be manufactured by letting it grow. The polyester used here can be produced in the same manner as the polyester of component (a) above. The blending ratio of divalent carboxylic acid and divalent alcohol used in the production of such polyester is 1.1 to 1.5 moles of divalent alcohol to 1 mole of divalent carboxylic acid. If the amount of dihydric alcohol is less than 1.1 mol, it is not possible to obtain a polyester having hydroxyl groups at both ends, and if it exceeds 1.5 mol, there is a large amount of unreacted carboxylic acid. Undesirable.

In addition, polyether can be prepared, for example, by adding glycidyl (meth)acrylate to polytetramethylene ether glycol in an equivalent molar amount or more, and then reacting for 1 to 2 cycles at 80 to 90"C! in the presence of a polymerization inhibitor. It can be produced by heating and reacting.The average molecular weight of the polyether thus obtained is about 300 to 3.0
00, specifically PEG#300 and PEG# commercially available from Sanyo Chemical ■, NOF ■, Mitsubishi Chemical 11, etc.
400. PEG #1540, PTG well 600, PTG #
800, PTG#2100, etc.

Among component (b), polyether glycol has at least one (meth)acryloyl group in its side chain.For example, the polyether glycol has the following formula; ;X represents an integer of 4 to 20;y is 1 to 1
(represents an integer of 8; 2 represents an integer of 0 to 13).

Such polyether glycols include, for example.

It can be manufactured by the following method. That is, first, 1 to 18 mol of glycidyl (meth)acrylate is added to 1 mol of polytetramethylene ether glycol, and then heated at 80 to 90°C for 3 to 6 hours to cause a reaction.Next, approximately ethylene oxide is added to the reaction solution. After adding 1 mol, the mixture is heated at about 100° C. for 2 to 3 hours to carry out one reaction.

Component (b) has a (meth)acryloyl group at the terminal or side chain, but may also have another double bond-containing group 1, such as an allyl group. For example, in the above method for producing polyether glycol, by using allyl glycidyl ether instead of glycidyl (meth)acrylate, polyethylene glycol having an allyl group in the side chain can be obtained. Such polyethylene glycol having an allyl group in the side chain may be, for example, the following formula; (wherein, R represents a hydrogen atom or methylene;
y represents an integer of 1 to 18; 2 represents an integer of 0 to 13).

Component (c), which is a raw material for producing component (A), is at least 18t selected from the group consisting of di- or triisocyanate of an incyanul MIFJ conductor, carbodiimide-modified diphenylmethane diisocyanate, diphenylmethane diisocyanate, and polyisocyanate having a diphenylmethane structure. be. Therefore, two or more of these compounds can be used in combination to form the component (c). Examples of the di- or triisocyanate of the incyanuric acid derivative which is the component (c) include.

(cH2) 6 NCO COCN (cH2) a NCO CN (cI(2) 6NGO etc.); Examples of carbodiimide-modified diphenylmethane diisocyanate include; Examples of the polyisocyanate include:

etc., specifically, Millione) M
T, Millionone-1-MTL and Milionate MR (
(Product name: Nippon Polyurethane Industries).

Component (A) is manufactured by using the above-mentioned components (a) to (c) as raw material 4, and the manufacturing method thereof is 1, for example, as follows.

Each component (a) to (c) is dissolved in an inert solvent such as toluene, xylene, ethyl acetate, cyclohexanone, etc.
Dissolve to a concentration of about 1.2 to 1.6 g/-1
Then, the reaction is carried out at about 60 to 80°C for about 5 to 10 hours.
After the reaction is completed, the inert solvent is removed while heating under reduced pressure to obtain the polyurethane (meth)acrylate resin of component (A). The amount of components (a) to (c) used in the production of component (A) is 10 to 250 parts by weight, preferably 5 to 150 parts by weight of component (b) per 100 parts by weight of component (a). Seibu, component (c) is 55-20
0 parts by weight, preferably 80 to 150 parts by weight.

In addition, when producing component (A), if necessary,
A polymerization initiator such as di-n-butyltin dilauryphosphate and a polymerization terminator such as methanol may also be used.

Component (B), which is a constituent material of the film of the present invention, is a photosensitizer and/or a heat sensitizer.

Among the components (B), the photosensitizer is a necessary component when curing the polyurethane (meth)acrylate resin of the component (A) with ultraviolet rays. Examples of the photosensitizer include aromatic hydrocarbonized starch, benzophenone and its derivatives,
0-benzoyl anso.

Fragrant esters, acetophenones and their derivatives.

Benzoin and benzoin ethers and derivatives thereof,
Examples include quinone compounds and amines.

Among such photosensitizers, aromatic hydrocarbons include, for example,
Examples include phenanthracene, chrysene, anthracene, etc.; benzophenone and its derivatives include 1
For example, benzophenone, 2,4-dimethylbenzophenone.

Examples of 0-benzoylbenzoic acid esters include O-benzoylbenzoic acid ester, O-benzoylbenzoic acid methyl ester, O-benzoylbenzoic acid ester, and O-benzoylbenzoic acid ester. -benzoylbenzoic acid ethyl ester and 0-
Examples of acetophenone and its derivatives include acetophenone, 4-methylacetophenone, 3-methylacetophenone and 3-methoxyacetophenone; benzoin and benzoin ether and its derivatives; Examples of derivatives include benzoin, benzoin methyl ether, benzoin ethyl ether,
Examples of quinone compounds include benzoin isopropyl ether, benzoin n-butyl ether, and benzoin triphenyl ether; examples of quinone compounds include benzoquinone, naphthoquinone, anthraquinone, and 5,1
Examples of the amines include diphenylamine, carbazole, and triphenylamine; these photosensitizers can be used in combination of one or more. .

The blending ratio of the photosensitizer is 100 parts by 11 parts by component (A).
1 to 7 parts by weight, preferably 2 to 5 parts by weight. If the proportion of photosensitizer is less than 1 part by weight, curing will be insufficient, and even if it exceeds 7 parts by weight,
By further blending a heat sensitizer as the (B) component, the (A) component is made into a heat-curing type, which is undesirable because it can no longer be expected to improve the curing speed, etc., and increases the production cost. be able to. Examples of the heat sensitizer include inorganic peroxides, organic peroxides, and azo compounds. Among such heat sensitizers, examples of inorganic peroxides include potassium persulfate and ammonium persulfate; examples of organic peroxides include:
For example, benzoyl peroxide, parachlorobenzoyl peroxide, lauroyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, t-butyl hydroperoxide,
Examples of azo compounds include t-butylperoxyin butyrate, and examples include azobisisobutyronitrile.

Azobispropionitrile, diazoaminobenzene, p
-=) lobenzenediazonium 1118; one or more of these can be used. The blending ratio of such a heat sensitizer is 0.1=lffiffi parts, preferably 0.2 to 0 parts by weight per 100 parts by weight of component (A).
．． 7 parts by weight. When the blending ratio of the heat sensitizer is outside the above range, it is not preferred for the same reason as when blending the photosensitizer.

These photosensitizers and heat sensitizers can be used alone or in combination.

As the constituent material 4 of the film of the present invention, the above (A)
and CB) In addition to the ingredients, if necessary, further (meta)
Acrylic acid, ester thereof, or oligomers thereof (hereinafter referred to as "third component") can be blended. By blending such a third component, (
The constituent materials of the film consisting of components A) and (B) can be liquefied at room temperature, and the resulting film can have excellent flexibility, extensibility, and mechanical strength.

Among the third components, (meth)acrylic esters include, for example, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl methacrylate, 4-hydroxycyclohexyl acrylate, acrylamide, diaseptone acrylamide. , glycidyl methacrylate, N-methylolacrylamide, diethylene glycol diacrylate, 1.
Examples include 4-butanediol diacrylate, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate.

As the third component, a monomer component selected from acrylic acid, methacrylic acid and the above-mentioned esters thereof can be used alone or two or more kinds can be used in combination,
In addition to these, oligomers (average molecular weight of about 300 to 2,000) obtained from one or more of the above monomer components or a mixture of the monomer components and the above oligomers can be used.

The blending ratio of the third component is 50 to 350 parts by weight, preferably 80 to 20 parts by weight, based on 100 parts by weight of component (A).
It is 0 parts by weight.

The film of the present invention comprises a constituent material consisting of the above-mentioned component (A), and optionally component CB) and a third component;
can be obtained from The manufacturing method will be explained below. First, such constituent materials are heated at a temperature of 60 to 70°C to liquefy. The viscosity of the liquid heated in this way is approximately 200 cPs, and if it is left as is, it will become solid when cooled to room temperature, but if the third component mentioned above is added, the viscosity will be further reduced. Then, apply the liquid to a suitable material such as a polyethylene terephthalate resin film using an applicator or the like so that it has a uniform thickness. Apply to. Thereafter, the coated material can be cured by irradiation with active energy rays or heating to obtain a film.

In the method for manufacturing such a film, the thickness after '14 IHs can be appropriately determined depending on the use of the film. When curing by irradiation with active energy rays, for example, electron beams, X-rays, α-rays, β-rays, γ-rays, ultraviolet rays, and the like can be used. Irradiation conditions vary depending on the type of active energy ray used, film thickness, and film composition. For example, when using an electron beam, the irradiation intensity is about 1 to 20 Mrad. If the irradiation intensity is 1 Mrad without groove, curing will be insufficient at 112.

The resulting film retains some viscosity. Even when it exceeds 20 Mrad, there is almost no difference in the curability or physical properties of the resulting film.
When using ultraviolet light, usually IKW (80
W/c+a) 15 cI vertically below the high pressure mercury lamp
Under the condition that the object to be irradiated is placed at position 11, an irradiation time of several seconds is sufficient.

When curing by heating, it is usually sufficient to heat at a temperature of 100° C. or higher for about 10 minutes. In addition, when producing a film, it is possible to combine curing by irradiation with active energy rays and curing by heating. , completely cured, or the reverse order of operations. Such a curing method can be appropriately selected depending on the workability and the physical properties of the film to be cured.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

In addition, in the examples, all "parts" represent "parts by weight."

Example 1 747 parts of polytetramethylene ether glycol (average molecular weight approximately 1.200) and 1.4-butanediol were placed in a reaction vessel, mixed, and then heated at 120°C for 2 hours. %) of monohydroxy polyether monoacrylate (average molecular weight ■about 800) was added, and 1,36 parts of diphenylmethane-4,4'-diisocyanate was added.
0 parts was added and dissolved. Thereafter, the reaction was completed by heating at 70°C for 4 hours to obtain a polyurethane acrylate resin that was solid at room temperature.

Polyurethane acrylate 146 thus obtained
100 parts of fat and 1 part of 2-hydroxyethyl methacrylate
A masking tape film was produced using 00 parts of the mixture as constituent material 1 in the following manner. First, the mixture was heated at 60'0 to obtain a liquid material.Then, this liquid material was applied onto a polyethylene terephthalate film using an applicator so as to have a uniform thickness. after that,
The film was cured by irradiation with an electron beam having an intensity of 12 Mrad for about 1 second in a nitrogen stream to obtain a film having a thickness of 80 mm.

Next, one side of the obtained film was coated with 100% natural rubber.
Part and Alcon P100 (petroleum-based resin.

Product name: Arayo Chemical Industry■t! A rubber adhesive prepared by dissolving 70 parts of A) in toluene was applied to a thickness of 25 μm, and then dried at 80° C. for 10 minutes to obtain a masking tape.

The masking tape obtained in this way.

After applying the paint to the curved surface of the metal plate and spraying the paint over the entire surface, heat treatment was performed at 160°C for 30 minutes. This masking tape can be adhered to a metal plate in close contact and shows no shrinkage at all even after heat treatment. Even when Jq# was used, the parting property was good.

Example 2 After putting 720 parts of polytetramethylene ether glycol (average molecular weight about 1.200) into a reaction container, 120 parts of
It was heated at °C for 1 hour until it became liquid. Next, 47.6 parts of a hydroxyl-terminated monoacrylate polyether (average molecular weight: about 550) represented by the following formula; 000) was added and dissolved. Thereafter, 516 parts of 1,4-butanediol and 4 parts of diphenylmethane-4,4'-diisocyanate were added.
40 parts were added and the reaction was terminated by heating at 75°C for 6 hours to obtain a polyurethane acrylate resin.

To 100 parts of the polyurethane acrylate resin thus obtained, 100 parts each of 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate were added and dissolved, and as a photosensitizer, Irgacure 651 (trade name, A film was made using a liquid 774 compound obtained by adding and mixing 8 parts of methyl ethyl ketone peroxide (manufactured by ICI) as a constituent material, and a liquid mixture obtained by adding 8 parts of methyl ethyl ketone peroxide as a heat sensitizer instead of a photosensitizer. Manufactured.

First, the mixture was placed on a polyethylene terephthalate film in the same manner as in Example 1.Then, the mixture containing the photosensitizer was placed under a 1kW (80w/cm) high-pressure mercury lamp at a distance of 15cm, and A film having a thickness of 50 parts m was obtained by irradiating ultraviolet rays for seconds. Moreover, the one containing a heat sensitizer was heated at 120° C. for 10 minutes to obtain a film having a thickness of 50 parts.

Next, masking tapes were obtained in the same manner as in Example 1 using the two types of films obtained, and coating was performed in the same manner as in Example 1 using these.

As a result, the same results as in Example 1 were obtained for all tapes.

Example 3 Produced from 1,4-butanediol and adipic acid,
average molecular weight of about 500, both ends are hydroxyethyl, 11
After placing 400 parts of the buttoned polyester in a reaction container, the mixture was heated at 120°C for 1 hour.Next, 160 parts of monohydroxy polyether monoacrylate (average molecular weight about 550) represented by the following formula: % formula % was added. diphenylmethane-4,4' added and further modified with carbodiimide
- 250 parts of diisocyanate were added and dissolved. Thereafter, the reaction was completed by heating at 80° C. for 5 hours, and the polyurethane acrylate resin was obtained.

Then, the obtained polyurethane acrylate resin lOO
100 parts of 2-hydroxyethyl methacrylate) was added to 100 parts of 2-hydroxyethyl methacrylate, dissolved and allowed to cool to form a liquid at room temperature (viscosity 10).
0 cPs) was applied to a polyethylene terephthalate film in the same manner as in Example 1, and the electron beam irradiation intensity was increased to 10
The thickness was set to 25 in the same manner as in Example 1, except that Mrad was changed.
The film of μ custom was made f[t.

A masking tape was obtained in the same manner as in Example 1 using the film thus obtained. After this masking tape was attached to a metal plate having an uneven surface, paint was sprayed on the entire surface, and then heat treatment was performed at 180° C. for 30 minutes.

This masking tape could be adhered to the metal plate in close contact. Further, there was no shrinkage of the tape due to heating, and there was no lifting of the tape attached to the four parts.

Example 4 Polyethylene glycol (average molecule 51750) 747
and 53 parts of 1,4-butanediol into a reaction vessel,
After mixing, the mixture was heated at 120°C to make it liquid, and then
300 parts of monohydroxy polyester monoacrylate (average molecular weight approximately 1,450) represented by the following formula; Then, heat at 70°C for 6 hours.

Made of polyurethane acrylate resin.

Then, the obtained polyurethane acrylate resin 100
200 parts of 2-hydroxyethyl methacrylate was added and dissolved therein to obtain a liquid mixture (viscosity: 80 cPs) at room temperature. Then, to 100 parts by weight of the mixture, 20 parts of difunctional cyanuric acid derivative 9 represented by the following formula: It was used as a constituent material.

The obtained constituent material 1 was applied uniformly onto a polyethylene terephthalate film using an applicator, and then heated under a high-pressure mercury lamp at 1 kW (80 W/CI) (7) in a nitrogen stream at a distance #t of 5 cm for about 2 hours. A film was obtained by irradiating ultraviolet rays for seconds.

A masking tape was obtained in the same manner as in Example 1 using the obtained film. After pasting this masking tape on the curved part of the metal plate and then spraying paint on the entire surface,
Heat treatment was performed at 230°C for 20 minutes. This masking tape could be adhered to a metal plate in close contact with it, showed no shrinkage at all even after heat treatment, and had good separation properties even when the tape was peeled off.

[Effects of the Invention] As explained above, the film of the present invention can be manufactured by:
In particular, in the curing process, no treatment that applies external force, such as stretching, is performed, so the resulting film has no directionality, and therefore does not shrink even when heated. Excellent stability. The film of the present invention also has excellent flexibility and heat resistance.

Therefore, since the film of the present invention has the above-mentioned excellent properties, when it is used as a base material for masking tape in painting work in various fields, it will not cause deformation due to deterioration or shrinkage of the masking tape due to heat. Moreover, since it can be adhered to surfaces with uneven or curved surfaces in close contact, there are almost no chances of painting mistakes.

Procedural amendment March 1988 Commissioner of the Japan Patent Office Black ■1 Mr. Akihiro I, “Indication of the matter 1987 Patent Application No. 287764 2, Title of invention Masking tape film 3, Case of person making amendment Relationship with Patent applicant name Nichiban Co., Ltd. 4, Agent 5, Date of amendment order Voluntary action 6, Subject of amendment Column 7 for detailed explanation of the invention in the specification Contents of amendment ≧ - (1) Specification No. "Vinyl chloride film" written on page 4, line 5 is corrected to "vinyl chloride film."

(2) Specification page 22, line 1θ to line 11 and line 28
"Irradiation intensity" written on the 18th line of the page is corrected to "Irradiation dose."

(3) "Strength" stated on page 24, line 18 of the specification is r
Corrected to "dose".

Claims (1)

[Scope of Claims] (A) (a) A polyester or polyether having a hydroxyl group at the end and at least two or more active hydrogens in one molecule; (b) A hydroxyl group at either end and at least one unsaturated polyester selected from the group consisting of polyesters or polyethers having a (meth)acryloyl group at the other end, and polyether glycols having a (meth)acryloyl group in the side chain. ether; and (c) at least one member selected from the group consisting of diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, and polyisocyanate having a diphenylmethane structure; and (B) ) A film for masking tape, comprising as a constituent material a photosensitizer and/or a heat sensitizer, if necessary.