JPS61185571A - Curing of oil-modified alkyd resin composition - Google Patents

Abstract

PURPOSE:A metallic base material is coated with an oil-modified alkyd resin containing a specific oil-modified alkyd, polymerizable monomers and metal salt of an organic carboxylic acid in a specific proportion and heated at a specific temperature to form a coating film of high resistance to flex and to shock. CONSTITUTION:A metallic base material is coated with an oil-modified alkyd resin composition containing (A) 70-90wt% of a resin of (i) an alkyd modified with linolenic acid and/or linolenic acid, thus having 25-70% oil length, or (ii) a mixture of 20-80wt% of (i) oil-modified alkyd and 80-20wt% of an unsaturated polyester, (B) 30-10wt% of polymerizable monomers soluble in components A and C, preferably acrylic compound bearing acryloyloxy group and (C) 0.01-1wt% of an organic carboxylic acid metal salt such as cobalt naphthenate, then the coating film is cured by heating at 80-300 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is useful as a coating method for manufacturing decorative steel plates for steel furniture, steel shelves, Roneos, etc.

It can also be applied as a method for making ink more convenient.

[Prior art]

Oil-modified alkyd resins are generally prepared from polybasic acids, polyhydric alcohols, and unsaturated fatty acids, and take advantage of the property of hardening when the double bonds of the unsaturated fatty acids in the ingredients participate in a crosslinking reaction with oxygen in the air. It is used in various types of paints such as air-drying paints and baking paints (Special Public Interest Publication in 1973).
No.-431, No. 58-46274, JP-A-53-52
No. 596, No. 53-67792, No. 56-50910
No. 53-69251).

When considering that fatty acids in the resin react with glycerin to form triglycerides in oil-modified alkyd resins, the weight percentage of the triglycerides in the resin is called the oil length, which depends on the physical properties of the paint, i.e., solubility, It is an important index for determining hardness, gloss, color retention, weather resistance, curing time, storage stability, etc. For example, increasing oil length helps to increase the flexibility of a++, A and its solubility in organic solvents, but tends to decrease the hardness of the coating. On the other hand, while reducing oil length helps improve the gloss and color retention of the coating, it tends to reduce the spreadability of the paint. Of course, it is not only the oil length that determines the physical properties of the coating described above, but these properties are also governed by the properties of the other components of the oil-modified alkyd resin.

Conventionally, oil-modified alkyd resins have an oil length of 30% to 80%.
% is generally dissolved in a solvent such as turpentine oil or toluene and used as an air-drying paint, and a mixture of this with an amino resin is used as a baking paint.

These solvent-based paints provide films with excellent weather resistance and adhesion to metals. However, the solvent evaporates, causing air pollution problems.

An air-drying oil-modified alkyd resin paint that does not use a solvent, that is, (A) an oil-modified alkyd resin (B) a polymerizable monomer that dissolves the above component (A), a radical polymerization initiator, and a metal drying agent. Solvent-type (non-polluting fil) @ materials are also known (JP-A-53-52596, JP-A-53-67792,
No. 53-69251), these publications include this air drying! !
! Some suggest that the paint can also be used as a baking paint.

However, these non-polluting air-drying oil-modified alkyd resin compositions contain a polymerization initiator as component C) and a metal desiccant as component (2), and therefore have a short pot life. Sub-composition* (liquid I),
(O component dissolved (silicic acid separation or (D solution (■ night)
must be mixed before use.

[Problems that Gimei tries to solve]

The purpose of the present invention is to improve the pot life of non-polluting type and #l type pots.

[See the problem! 4. IF physical means to decide] The present inventor is
It was discovered that when heated at ~300° C. without the above-mentioned zero component polymerization initiator, it cured and formed a film, and the present invention was achieved.

That is, the present invention provides the following components: (A) Component: (fatty, oil-modified alkyd of 25-70% oil length modified with linoleic acid and/or linolenic acid, or (koji, oil-modified alkyd of 20-80% oil length of (a) above) A mixture of 80% to 20% of unsaturated polyester and 80% to 20% of unsaturated polyester is heat-treated to give a resin of 70% to 90% by weight, in which both are uniformly compatible. 30% to 10% polymerizable monomer Ω component: Metal salt of organic carboxylic acid 0.01 to 1% of the sum of component (A) above and the resin content of the component
The oil-modified alkyd resin composition containing the above (to), (B) and C) components is coated on a metal substrate, and then 80 to 30% by weight (in terms of metal) is applied.
The present invention provides a method for curing an oil-modified alkyd resin @ composition, which is characterized by curing by heating at 0°C.

(Component A) The oil-modified alkyd resin (a), which is a component of the oil-modified alkyd resin composition according to the present invention, is essentially different from conventional oil-modified alkyd resins or oil-modified alkyd resins to be provided in the future (α , β-unsaturated monocarboxylic acid (including those modified by α, β-unsaturated monocarboxylic acid. The method of modification with α, β-unsaturated monocarboxylic acid is also the same as the method of modifying ordinary alkyd tree 11 with fatty acid).

Therefore, the polybasic acid components of the alkyd resin include phthalic anhydride, isophthalic anhydride, tetrahydrophthalic anhydride, adipic acid, sebacic acid, azelaic acid, various conjugated double bond-containing isobrene dimers, and maleic anhydride.・1,2,3,6-tetrahydrophthalic anhydride derivatives having 1111I chain obtained by alda-addition reaction, such as myrcene maleic anhydride, alloocimene maleic anhydride, ocimene maleic anhydride, 3-(β
-methyl-2-butenyl)-5-methyl-1,2,3,
Aromatic, aliphatic or ring group saturated or unsaturated polybasic acids such as 6-titrahydrophthalic acid, hexahydrophthalic anhydride, 4-methyltetrahydrophthalic anhydride and trimellitic acid are used or used in combination. As long as gelation does not occur, part of the saturated polybasic acid may be replaced with an α,β-unsaturated polybasic acid such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, etc. Among these, particularly preferred polybasic acids are phthalic acid and 3-(β-methyl-2-butenyl)-5-methyl-1,2,3,6-tetrahydrophthalic anhydride (under μ, abbreviated as MBTHP). ).

When MBTHP is used as part of the polybasic acid, it has a remarkable effect on lowering the viscosity of alkyd resins.

Polyhydric alcohol components include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, neopentyl glycol, glycerin, pentaerythritol, trimethylolpropane, trimethylolethane, tris(2-hydroxyethyl ) Incyanurate etc. are used alone or in combination. Generally, dihydric to tetrahydric alcohols having 2 to 12 carbon atoms are common.

The oil or fatty acid forming the oil-modified alkyd resin includes those having air-drying properties, such as oils and fats such as linseed oil, soybean oil, tall oil, and safflower oil, or fatty acids separated therefrom.

In the present invention, in order to obtain better adhesion to metals, the oil-modified alkyd resin consisting of the above three essential components may be roughly modified with an α,β-nonanastomeric monocarboxylic acid. The α,β-unsorated monocarboxylic acids used here are crotonic acid, sorpic acid or 2-(β-furyl)acrylic acid.

Among these, sorbic acid is particularly preferred.

These α,β-unsaturated monocarboxylic acids introduced into the oil-modified alkyd resin are thought to react in the same way as oil-modified fatty acids and exist as side chains in the alkyd resin, but these acids are When a polymerizable single substance is used as a component (intestine) in the composition of the invention, it radically copolymerizes with it and contributes to curing, so it has a great effect on hardening and improving water resistance of the resulting coating film.

Oil-modified alkyd resins are produced from these three essential components or four components by conventional methods, but specifically, for example,
A method in which α, β-unsaturated monocarboxylic acids, fatty acids, polybasic acids, and polyhydric alcohols are simultaneously charged and reacted, or a fatty acid, a polybasic acid, and a polyhydric alcohol are first reacted, and then α, β-unsaturated There is a method of reacting monocarboxylic acids. The latter is preferred from the viewpoint of preventing gelation during production. These components can be subjected to the reaction in the form of their functional derivatives, such as esters such as fats and oils themselves. In addition, when using fats and oils, it is common to perform transesterification by reacting only a polyhydric alcohol and an ester in advance. Furthermore, in any method, it is desirable to add an antigelation agent such as hydroquinone to avoid gelation during the reaction.

The oil-modified alkyd resin of component (A) used in the present invention has an oil length of 25 to 70%, preferably 55 to 65%. If the oil length is less than 25%, it will cause a decrease in the water resistance of the resulting coating film, while if it is 70% or more, undesirable phenomena such as a decrease in the initial drying hardness of the resulting coating film and a decrease in surface smoothness will occur. . Note that the oil length in the present invention is the it% of the monobasic acid triglyceride derived from the oil or fat in the oil-modified alkyd resin after modification with an α,β-unsaturated monocarboxylic acid or a fatty acid separated therefrom.

The α,β-unsaturated monocarboxylic acid content in the α,β-unsaturated monocarboxylic acid-modified oil-modified alkyd resin used in the present invention is 0.5 to 30% by weight, preferably 2 to 15% by weight.
%. If it is less than 0.5%, no effect of improving the water resistance and hardness of the resulting coating film can be expected, while if it exceeds 30%, gelation will occur significantly during alkyd production, making it difficult to produce.

Oil-modified alkyd tree @ or α, β- used in the present invention
The acid value of the unsaturated monocarboxylic acid-modified oil-modified alkyd resin is usually about 5 to 40.

80 to 20% by weight of the above component (a) was replaced with unsaturated polyester, and the mixture was heat-treated to uniformly dissolve the two components.'1! tl'1W(b) may be used as a captive component (Japanese Patent Application Laid-Open No. 58-21459).

This unsaturated polyester is obtained by reacting an unsaturated dibasic acid, a saturated polybasic acid, and a polyhydric alcohol.
Examples of the unsaturated dibasic acids used to synthesize such unsaturated polyesters include maleic anhydride, fumaric acid, and itaconic acid, which may be used alone or in combination of two or more.

As the saturated polybasic acid, those used in the above-mentioned alkyd production can be used, and generally phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, 3.6
-Nindomethylenetetrahydrophthalic anhydride, MBTH
P etc. are used.

The proportion of unsaturated dibasic acids in polybasic acids is 10 to 70
If the amount is less than 10 mol%, it will take a long time to heat the mixture of oil-modified alkyd and unsaturated polyester, and the drying properties of the paint will deteriorate. Furthermore, the hardness of the resulting coating film is also low. On the other hand, if it exceeds 75 mol%, a lot of gel-like material will be generated when the mixture of oil-modified alkyd and unsaturated polyester is heat-treated, making it impossible to use it in paints.

In addition to the aforementioned polyhydric alcohols used in the synthesis of oil-modified alkyds, examples of polyhydric alcohols include 1,2-butanediol, 1,5-bentanediol, 1,6-hexanediol, and 1,10-decane. Diol, ethylene oxide and/or propylene oxide addition reaction product of bisphenol A, cyclohexane dimetatool, dicyclopentadiene dimethanol, etc. alone or in combination
More than one species can be used together.

Various conventional methods of removal can be used to produce the unsaturated polyester of the present invention. The aforementioned unsaturation and pj! Although the Wada tetrabasic acid component and the polyhydric alcohol component may be prepared and reacted at the same time, it is preferable that a saturated 41] dibasic acid such as phthalic anhydride and a polyhydric alcohol be prepared in the same manner.
Yu, maleic anhydride, etc., which were prepared in the temple and reacted.
, j1] By introducing a dibasic acid, it is possible to produce an unsaturated polyester with good reproducibility without causing gelation.

This unsaturated polyester has a halic acid value of 10 to 40, preferably 20 to 30. If the acid value is less than 10, gel is likely to be formed during heat treatment, and if it exceeds 40, the resulting coating film will have insufficient hardness and water resistance for practical use.

The heat treatment of the mixture of the oil-modified alkyd and the unsaturated polyester is performed so that the mixture of the oil-modified alkyd and the unsaturated polyester accounts for 20-80% by weight, preferably 40-60% by weight of the sum of the oil-modified alkyd and the unsaturated polyester.
wt% mixture of toluene, xylene,
This is carried out by adding a solvent such as mineral spirit to lower the viscosity and heating at 180 to 240° C. for 30 minutes to 12 hours while stirring.

Through this heat treatment, the hydroxyl groups in the carboxyl groups present in each molecule of the oil-modified alkyd and unsaturated polyester undergo a metal-coupling reaction, and the oil-modified alkyd and unsaturated polyester are combined.* A portion of fat is formed, resulting in oil-modified When used as a compatibilizer for alkyd and non-foamed polyester, a resin in which both are uniformly compatible can be obtained.

In particular, if an unsaturated fatty acid having a conjugate bond is used as the sanitary acid component of the raw material for oil-modified alkyd, and maleic anhydride or fumaric acid is used as the unsaturated polybasic acid of the unsaturated polyester raw material, oil-modified alkyd based on these Since the double bonds in the molecules of the unsaturated polyester also undergo an addition reaction upon heating, uniform compatibilization of the oil-modified alkyd and the unsaturated polyester can be achieved by a short heat treatment.

After the heat treatment, by-product water and added organic solvent are uniformly removed from the compatible resin.

The four fingers (b) in which the oil-modified alkyd and the unsaturated polyester are uniformly mixed are obtained by heat treatment of the mixed proboscis and are dissolved by the polymerizable monomer (B), and a uniform liquid is prepared. be done.

[B component]

Preferred polymeric compounds for dissolving the metal desiccant (A) and (C) [ingredients] are acrylic compounds having an acryloyloxy group, such as charcoal 2
Mono-1t/j, polyacrylates and methacrylates (hereinafter referred to as (meth)acrylates) made of esters of ~20 alcohols and acrylic acid or methacrylic acid are preferred. This material may have a hydroxyl group, an alkoxy group, etc., and since the purpose of the resin composition for paint is to provide a cooling effect for room temperature drying or heat drying, a high boiling point one is preferable. . Basically, cyclohexyl (meth)acrylate, benzyl (
meth)acrylate, 2-ethoxyethyl(meth)acrylate, 2-butoxyethyl(meth)acrylate,
Tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-allyloxy-2-
Hydroxypropyl (meth)acrylate, 3-butoxy-2-hydroxypropyl (meth)acrylate, 2
-hydroxy-1-7enethyl (meth)acrylate,
2-hydroxy-2-phenethyl (meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, 1,3-butanediol (meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanethiol di(meth)acrylate, neobentyl glycol di(meth)acrylate, glycerin monoacrylate monomethacrylate, glycerin monomethacrylate monohalf maleate, trimethylolpropane tri(meth)acrylate
acrylate, pentaerythritol tri(meth)acrylate, etc., and these can be used alone or in combination.
More than one species can be used. Among these polymerizable monomers, particularly preferred are d, 1,3-butanediol mono(meth)acrylate acrylate, neopentyl glycol mono(meth)acrylate, and trimethylolpropane tri(meth)acrylate.

A part of these (meth)acrylates may be replaced with styrene. Also, since tri(meth)acrylates have a high viscosity, they should not be used much except for the purpose of improving first-order hardness, but when used, = u! Used in combination with 1jJ mono(acrylate), di(meth)acrylate, etc.

The polymerizable monomer of this (1) component is used in a ratio of 10 to 30% by weight in the resin ((sum of N component and (containing component)) forming the skin. If the amount is less than 107JI%, the paint will have a high viscosity and will be difficult to apply6.If it exceeds 70JI%, the drying properties of the paint will not only be impaired, but the resulting impact resistance will be reduced. It's bad.

[C component]

Examples of organic carboxylic acid metal salts which are gold 4 desiccants include cobalt salts, lead salts, calcium salts, manganese salts, and zinc 1 salts of octenoic acid or naphthenic acid. These F
i≠Used alone or in combination of two or more.

These (01 sentences worth of organic carboxylic acid gold 4 salts are (A)
For 100 parts by weight of the sum of 1 serving of ingredients and (B),
It is used in a ratio of 0.1 to 2 parts (excluding metals).

[1-1: Ingredients] In addition to the above (he, ω) and (0 ingredients), pigments such as calcium carbonate, titanium oxide, M powder, and yellow lead, thickeners such as CMC and polyvinyl alcohol, toluene, and xylene. , a solvent such as mineral spirits, and a fungicide 24fc may be added as necessary.

[Painting method]

The paint containing the components (A), [F]) and (0) is applied onto a base material such as a steel plate, a raccoon lead plate, or a stone slab using a roll, brush, spray, etc., at a temperature of preferably 80 to 300°C. is 12
By heating and curing at 0 to 200°C, a film with excellent adhesion to the base material can be formed.

〔effect〕

According to the method of the present invention, the pot life of the paint (pot life
Tsukasa) is stable even after six months, and has good adhesion to the base material.
A film with excellent bending resistance, bending resistance, and impact resistance can be obtained.

Production example of oil-modified alkyd Production examples 1 to 1 60 parts of dog bean oil fatty acid and 2 parts of phthalic anhydride were placed in a reactor equipped with a stirrer, thermometer, cooler, water separator, and nitrogen inlet pipe.
2 parts, glycerin 4.6'I pentaerythritol 15
．． After adding 0.05 parts of hydroquinone and 4 parts of xylene, the reaction was carried out at 220° C. in a nitrogen stream. When the acid value of the generated alkyd reached 40, 5 parts of sorpic acid and 0.05 part of hydroquinone were added, and the reaction was continued until the acid value reached 10, resulting in a norbic acid component concentration of 5.0% and an oil length of 62. A .7% oil-modified alkyd resin (resin-A) was obtained.

Production row-2 60 parts of soybean oil fatty acid, 27 parts of phthalic anhydride, 15.1 parts of glycerin, and 5.1 parts of pentaerythritol were prepared.
After further adding 0.05 parts of hydroquinone and 4 parts of xylene, the same reaction as in production row-1 was carried out at 220°C in a nitrogen stream to obtain oil-modified alkyd resin 11<at resin-B with an oil length of 62.7%. ) was obtained.

Production example-3 Dehydrated castor oil fatty acid 55.6 parts, phthalic anhydride 15.3 parts
'4 7.9 parts of glycerin, 11 parts of pentaerythritol
67 parts of sorpic acid and 4.4 parts of sorpic acid were used, but the reaction was carried out in exactly the same manner as in Production-1 manufactured by I, and the "norbic acid" component was obtained.
One line of oil-modified alkyd (@11-C) with 4.4 parts of I fertilizer and 58.1% oil length was obtained.

ll! ! ! 662 parts of dehydrated castor oil fatty acid, 27 parts of phthalic acid free, 1561 parts of glycerin, and 5.1 parts of pentaerythritol were reacted in exactly the same manner as in Production Example-2. r%
An oil-modified alkyd resin (Ki H-D) was obtained.

Visual example-5 Production of oil-modified alkyd! ! ! The oil-modified alkyd resin with sorbic acid component 4 degree of 4.4% and oil length of 58.1% of the production column-3 was reacted to an acid value of 25 to obtain oil-modified alkyd resin 11 with oil length of 58.1%.
(・1・vs.l = FJ) I asked.

1 Production Example J-6 Dehydrated castor fat $56.5 parts, phthalic anhydride 15.
0 parts, MBTHP 11.9:l (S, glycerin 6.
7 parts, pentaerythritol 13.54 parts, and crotonic acid 3.5 parts, the reaction was carried out in exactly the same manner as in Production Example-1 to obtain a crotonic acid component concentration of 3.5% and an oil length of 59.0%.
An oil-modified alkyd tree (#@-G) was obtained.

a1 Example-7 Dehydrated castor oil fatty acid 54.6 = ffl, phthalic anhydride 15.1 parts, MB THP 12.0, glycerin 7.7 parts, pentaerythritol 12.1 parts and 2-
The reaction was carried out in exactly the same manner as in Production Example-1 except that (β-furyl)acrylic acid 5.44% was used. A modified alkyd resin (Resin-H) was obtained.

Production Example-8 11 222 parts of 7-talic anhydride and 224.6 parts of neopentyl glycol were charged into the same production equipment as in Example-1.
After adding 20 parts of xylene, 210 parts of xylene was added under a nitrogen stream.
After reacting to an acid value of 30 to 15 at °C, the mixture was cooled. Charge 58 parts of fumaric acid and 0.254 parts of hydroquinone,
The reaction was carried out at 10° C. until the acid temperature became 125 or less. Water, xylene, etc. were removed to obtain a pale yellow unsaturated polynisder jugejima (Juki 111-J) having an acid value of 24.

In a manufacturing device similar to Manufacturing Example-1, 8100 parts of resin and
Add 00 parts of resin-Jl, and add 10R1 of xylene.
was added, and the reaction was carried out at 180° C. under a nitrogen stream. Successively, the little healing resin was extracted from the reactor and diluted with toluene for 50 min.
The viscosity at 25°C of the diluted t%
Established.

Its viscosity at 25°C is 150 centipoise (CP
After reacting until reaching S), water, xylene, etc. were removed to obtain a uniformly miscible resin (resin-K).

Evaluation of Paint Fabric Examples 1 to 9, Comparative Rows 1 to 13 Oil-modified alkyd resin was dissolved in the polymerized resin shown in Table 1 below to the indicated concentration. A specified curing agent was added to this solution, and the resulting paint was applied to a polished mild steel plate (50 m + x 150, wall thickness 0.3 rrra, ◆ with 320 polishing cloth, snoring, Atsushi) to a thickness of 3oμ. Thereafter, it was dried for 10 minutes in an air bath at 150°C.

The obtained model object was judged under the conditions described in F.

The results are shown in Table-1.

Hardening agent ■Kinke-Ko drying agent ■Polymerization initiator Cyclohexanone peroxide 1.0 parts Henji B soot viscometer (Tokyo total 4μs) Lead-edge hardness: JIS K-
56520, and determined by the presence or absence of scratches.Bending resistance: Based on JIS K-5400 (2me).

Passed (T), Biting (×) Melt resistance Note: Dubon impact strength 1 (7 inches, 5oO2 load, 50crR height) Passed <0>, Fracture (×) Surface smoothness Note 20 (smooth), Δ (Yuzuhada) Pot life: 20 (a month or more),

HPA: hydroxyglovir methacrylate BDDA
:1.4-butanediol diacrylate TMP-TM
A: Trimethylolpropane trimethacrylate PET-TMA: Pentaerythritol tetramethacrylate (blank below) Good-2 Painting properties table-2 (continued)

Claims (1)

[Claims] 1) Component (A): (a) an oil-modified alkyd with an oil length of 25 to 70% modified with linoleic acid and/or linolenic acid; or (b) an oil-modified oil of the above (a). Alkyd 20-80% by weight
A mixture of 80 to 20% by weight of unsaturated polyester and 70 to 90% by weight of a resin in which both are uniformly miscible with each other Component (B): The above (A) component and the following (C) component are dissolved. Polymerizable monomer: 30 to 10% by weight (C) Component: Metal salt of organic carboxylic acid 0.01 to 0.01 to the sum of the resin content of the above components (A) and (B)
1% by weight (in terms of metal) The oil-modified alkyd resin composition containing the above components (A), (B) and (C) is applied onto a metal substrate, and then 80-3% by weight is applied.
A method for curing an oil-modified alkyd resin composition, which comprises heating and curing at 00°C. 2), an oil-modified alkyd resin in which the oil-modified alkyd of component (A) is modified with an α,β-unsaturated monocarboxylic acid selected from sorpic acid, crotonic acid, and 2-(β-furyl)acrylic acid (however, The curing method according to claim 1, characterized in that the content of α,β-unsaturated monocarboxylic acid is 0.5 to 30% by weight.