JP2589172B2 - Surface coated glassware - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-coated glass product having a scattering-preventing property, the surface of which is coated with a specific multilayer resin layer.

2. Description of the Related Art In order to prevent personal injury when glass products such as glass bottles and fluorescent lamps are damaged, various methods of applying resin coating to glass products have been proposed, and some of them have been put into practical use.

For example, Japanese Patent Publication No. 52-21939 (JP-A-48-30580) discloses that an aqueous emulsion containing a thermoplastic resin or a rubber derivative as a main component is applied to the outer surface of a glass bottle filled with a carbonated beverage. It discloses a method of drying and drying to form a coating film having a thickness of 0.01 mm to 1 mm to prevent scattering of glass fragments at the time of rupture.

Japanese Patent Publication No. 53-404 (JP-A-48-94717) discloses:
(1) a reaction product of polyethylene glycol or polypropylene glycol having a molecular weight of 500 to 3000 and xylylene diisocyanate or isophorone diisocyanate,
Shown is a glass bottle fortified composition consisting of (2) 1,4-butanediol or 1,6-hexanediol and (3) 3.3'-dichloro4.4'-diaminodiphenylmethane.

JP-A-61-103965 discloses a coating agent containing 1 to 30% by weight of a linear polyurethane resin, and shows that this coating agent is suitable for preventing scattering when glass is broken. Have been. Specific examples of the linear polyurethane resin include a reaction product of polytetramethylene glycol and tolylene diisocyanate, a reaction product of polycarbonate diol and 4,4'-methylenebis (cyclohexyl isocyanate), and a reaction product of polytetramethylene glycol and isophorone diisocyanate. The reactants are listed.

It is also known to cover a glass bottle with two resin layers.

For example, JP-B-52-36072 (JP-A-51-31575) discloses that the surface is coated with a maleic acid-modified or maleic anhydride-modified ethylene-vinyl acetate copolymer, and the upper layer is coated with an acrylic or methacrylic compound. A splash resistant glass bottle coated with resin is shown.

JP-B-52-48875 (JP-A-48-81688) discloses that a surface of a glass bottle which has been treated with a primer is coated with a solvent-free urethane paint and has a tensile strength of about 50 kg / cm ² or more and an elongation of about 100 kg. A method for strengthening a glass bottle in which a coating of not less than 50% is applied to a thickness of 50 μm or more is shown.

Although it relates to an adhesive, Japanese Patent Application Laid-Open No. 61-9947 discloses that A polyurethane adhesive comprising a group-containing polyurethane, that is, a polyurethane containing β-methyl-δ-valerolactone units is disclosed.

Problems to be Solved by the Invention However, the conventional method for preventing breakage by resin coating, although significantly improved scattering prevention compared to the case of no coating, is still required to be improved, Thin film properties, scratch resistance, hot water resistance, blocking resistance,
Even if it has some of the required characteristics or requirements such as heat resistance, alkali resistance, weather resistance, painting workability,
It did not have all of them.

The present invention has been made in view of the above circumstances, and has been made to provide a surface-coated glass product having extremely excellent scattering prevention properties and having all the other required characteristics or requirements as described above. It is.

Means for Solving the Problems The surface-coated glass product of the present invention, on the surface of the glass product,
Polyester polyol (a1) selected from the group consisting of β-methyl-δ-valerolactone polyester polyol and 3-methyl-1,5-pentanediol polyester polyol, and 4,4′-methylenebis (cyclohexyl isocyanate) (a2 A) a layer of a polyurethane resin (A), which is a reaction product of (a) with a polyacryl polyol (b1) and an alkylated melamine (b2) on the primary coating layer. It has a configuration in which a layer of a thermosetting acrylic melamine resin (B) is provided as a secondary coating layer.

 Hereinafter, the present invention will be described in detail.

Glass Products Glass products include various products such as glass bottles, flat glass, tubular glass, hollow glass, spherical glass, and foam glass.

Primary coating layer In the present invention, a layer of the following polyurethane resin (A) is first provided as a primary coating layer on the surface of a glass product.

As the polyurethane resin (A), a polyester polyol (a1) selected from the group consisting of β-methyl-δ-valerolactone polyester polyol and 3-methyl-1,5-pentanediol polyester polyol; The reactant with 4'-methylenebis (cyclohexyl isocyanate) (a2) is used.

Β-methyl-δ among the polyester polyols (a1)
-Valerolactone-based polyester polyol, A polyester polyol obtained by reacting β-methyl-δ-valerolactone alone or with a polyol represented by When expressed as Refers to a resin represented by a chemical formula such as

Here, as the polyol, various types of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, trimethylolpropane, etc. Is used.

Among the polyester polyols (a1), 3-methyl-1,
5-pentanediol-based polyester polyol is Is a polyester polyol obtained by reacting 3-methyl-1,5-pentanediol (other polyols can be used in combination) with a polybasic acid.

Here, polybasic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, 1,3-
Various polybasic acids are used, including cyclohexanecarboxylic acid, tetrahydrophthalic anhydride, and hetic acid.

In the present invention, 4,4′-methylenebis (cyclohexyl isocyanate) (a2) is used as the polyisocyanate to be reacted with the polyester polyol (a1). Other polyisocyanates are not as suitable as this compound in achieving the objects of the present invention.

Secondary coating layer A thermosetting acrylic melamine resin (B) layer is provided as a secondary coating layer on the primary coating layer composed of the polyurethane resin (A) layer described above.

As the thermosetting acrylic melamine resin (B),
A reaction product of a polyacryl polyol (b1) and an alkylated melamine (b2) is used.

The polyacryl polyol (b1) refers to a polyol having an OH group introduced into an acrylic copolymer. Examples of the monomer having an OH group include allyl alcohol, monoallyl ether of polyhydric alcohol, hydroxyethyl (meth) acrylate, and hydroxypropyl (meth) acrylate.

Alkylated melamine (b2) refers to alkoxymethyl melamine, that is, hexamethylol melamine obtained by reacting melamine with formaldehyde and alkoxylated most of the methylol groups, for example, hexamethoxymethyl melamine, hexapropoxymethyl melamine And hexabutoxymethylmelamine, hexapentyloxymethylmelamine, hexahexyloxymethylmelamine, or a mixed etherified melamine obtained by combining two or more thereof.

Coating method, film thickness The formation of the primary coating layer and the secondary coating layer on the glass product is performed by any method including a dipping method, a roll coating method, a spraying method, a spin coating method, a brush coating method, and a curtain flow coating method. be able to.

When the immersion method is adopted, the concentration of the polyurethane resin (A) solution in forming the primary coating layer is often about 5 to 15% by weight, and the thermosetting acrylic melamine resin (B) is used in forming the secondary coating layer. ) Solution concentration is 20-40% by weight
It is often, but not necessarily limited to.

The thickness of the layer of the polyurethane resin (A) as the primary coating layer is suitably from 5 to 100 μm, particularly from 10 to 50 μm, and the thickness of the layer of the thermosetting acrylic melamine resin (B) as the secondary coating layer. Suitably, the thickness is 2 to 20 μm, especially 5 to 15 μm.
If the thickness of the layer of the polyurethane resin (A) is too thin, the anti-scattering property is insufficient, while if it is too thick, it becomes economically expensive. Further, if the thickness of the thermosetting acrylic melamine resin (B) is too thin, it is easily damaged, which impairs the appearance and affects the anti-scattering property. On the other hand, if the thickness is too thick, the elongation of the primary coating layer will increase. It is hindered, and on the contrary, the anti-scattering property is insufficient.

And not only the thickness of the layer of the polyurethane resin (A) and the thickness of the layer of the thermosetting acrylic melamine resin (B) are in the above range, but also the thickness ratio of the former to the latter is 10 to 1,
In particular, it is desirable to be in the range of 8 to 2, and in such a case, the breakage prevention and other physical properties are most effectively balanced.

Functions and Effects of the Invention The layer of the polyurethane resin (A), which is the primary coating layer, is a layer having excellent rubber elasticity. This layer adheres to the surface of the glass product, but does not adhere firmly and can be easily peeled off. The light adhesion of the layer of the polyurethane resin (A) to the glass surface effectively acts to prevent breakage. If the layer having rubber elasticity is firmly adhered to the glass surface, the cushioning property at the time of breakage is insufficient.

The layer of the thermosetting acrylic melamine resin (B), which is the secondary coating layer, has an effect of preventing damage which causes damage, that is, has excellent scratch resistance, hot water resistance, blocking resistance, and heat resistance. Excellent surface characteristics such as alkali resistance and weather resistance. In addition, this layer plays an important role of preventing the layer of the polyurethane resin (A), which is the primary coating layer, from being excessively stretched at the time of breakage.

Thus, the flexibility of the layer of the polyurethane resin (A), which is the primary coating layer, the light adhesion to glass products,
Thermosetting acrylic melamine resin (B) as a secondary coating layer
The surface characteristics of these layers are skillfully complemented, and the laminated structure of both layers is effective in preventing damage even though it is a thin film.

EXAMPLES Next, the present invention will be further described with reference to examples.

Hereinafter, "parts" refers to parts by weight.

Example 1 Polyurethane resin paint 200 parts of toluene and dimethylformamide 34 in a reaction vessel
And 82.4 parts of β-methyl-δ-valerolactone-based polyester polyol (Kuraray Co., Ltd., “Kurapol L-2010”, average molecular weight: about 2000) represented by the following formula, and stirred to 50 ° C. Dissolved while heating.

Then, 4,4'-methylenebis (cyclohexyl isocyanate) (Desmodur W manufactured by Bayer) 12.7
And 0.01 part of dibutyltin dilaurate were charged and reacted at 90 ° C. for 5 hours, and then cooled to room temperature.

To the obtained reaction solution, 467 parts of toluene, 167 parts of isopropyl alcohol and 34 parts of ethylene glycol monoethyl ether (ethyl cellosolve) were added to adjust the concentration,
A polyurethane resin paint was prepared.

274 parts of an acrylic resin solution (“Aromatex Y-201” manufactured by Mitsui Toatsu Chemicals, 50% non-volatile content) in a dissolving tank of thermosetting acrylic melamine resin paint,
Melamine resin solution (Mitsui Toatsu Chemical's “Uban
225 ", nonvolatile content 60%) 98 parts, xylene 210 parts, n-butyl alcohol 200 parts, methanol 20 parts, slip agent (" Floren AC-100 "manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.)
1 part, catalyst (Catalyst 600 manufactured by Mitsui Toatsu Chemicals, Inc.)
0 ") 2 parts, vinyltriethoxysilane (Toshiba Silicone Co., Ltd. silane coupling agent" TSL-8331 ")
One part was added and stirred well to obtain a thermosetting acrylic melamine resin paint in a uniform solution.

Coating of glass bottle A glass bottle for carbonated beverages having a content of 1000 ml is dipped in the above polyurethane resin paint, pulled up, heated and dried at a temperature of 30 ° C. for 1 hour, and then dipped again to room temperature.
Left for days. As a result, a primary coating layer having a thickness of 40 μm was formed.

Next, the glass bottle with the primary coating was immersed in the above-mentioned thermosetting acrylic melamine resin paint, pulled up, heated and dried at a temperature of 50 ° C. for 1 hour, and further heated at a temperature of 180 ° C.
The mixture was heated and cured at 5 ° C for 5 minutes. As a result, a secondary coating layer having a thickness of 16 μm was formed.

The ratio of the thickness of the primary coating layer / secondary coating layer is 40/16 = 2.5.

Example 2 113 parts of xylene and ethylene glycol monoethyl ether acetate (cellosolve acetate) 20 in a reaction vessel
Parts, 43.7 parts of β-methyl-δ-valerolactone-based polyester polyol (Kuraray Co., Ltd., “Kurapol L-1010”, average molecular weight: about 1000) represented by the following formula and charged to 50 ° C. under stirring. Dissolved while heating.

Then, 4,4'-methylenebis (cyclohexyl isocyanate) (Desmodur W manufactured by Bayer) 12.7
And 0.06 part of dibutyltin dilaurate, reacted at 90 ° C. for 6 hours, and then cooled to room temperature.

To the obtained reaction solution, 270 parts of xylene, 100 parts of n-butyl alcohol and 20 parts of ethylene glycol monoethyl ether acetate were added to adjust the concentration, thereby preparing a polyurethane resin paint.

Coating of Glass Bottle Using the polyurethane resin paint obtained above and the thermosetting acrylic melamine resin paint of Example 1, a primary coating layer and a secondary coating layer were formed on a glass bottle for a carbonated beverage having a content of 300 ml in the same manner as in Example 1. Formed. The thickness of the primary coating layer was 20 μm, the thickness of the secondary coating layer was 5 μm, and the ratio between the two was 20/5 = 4.

Example 3 3-methyl-1,5-pentanediol-based polyester polyol represented by the following formula (Kuraray Co., Ltd., "Kurapol P-2010", average molecular weight: about 2000) and 4,4'-
Using methylene bis (cyclohexyl isocyanate) (Desmodur W, manufactured by Bayer AG), a polyurethane resin paint was prepared in the same manner as in Example 1, and the primary coating layer and the secondary coating were applied to a 100 V, 60 W transparent bare light bulb in the same manner as in Example 1. The next coating layer was formed. The thickness of the primary coating layer was 10 μm, the thickness of the secondary coating layer was 5 μm, and the ratio between the two was 10/5 = 2.

<Test and Measurement Conditions> The coated glass bottles obtained above were tested and measured under the following conditions.

Appearance Measured visually.

Transparency Judged visually.

After filling the test bottle with carbonated beverage about 97% of the internal volume, stopper it, immerse it in a 40 ° C constant temperature bath so that the internal pressure becomes 4 kg / cm ² G, and then from the height of 75 cm It was dropped on a concrete floor in a horizontal posture, and the scattering distance of the glass piece at that time was evaluated according to the following criteria.

A: Glass pieces are not scattered. B: Glass pieces are scattered less than 50cm. C: Glass pieces are scattered more than 50cm. Slip angle. It was placed on a plate so as to be as it was, and the plate was gradually inclined, and the inclination angle when the plate began to slide was measured.

Scratch resistance Two test bottles were set up and down at an angle of 45 ° on a platform scale, and when the upper bottle was rubbed by applying force, the load in the gap where the coating film was damaged was measured.

Warm water resistance The glass was immersed in warm water at a temperature of 80 ° C. for 5 hours, and observed for abnormalities.

Hot water resistance The autoclave was placed in steam at a temperature of 121 ° C. for 1 hour, and observed for abnormalities.

Blocking resistance Fasten three test bottles with rubber bands and place them in warm water at a temperature of 80 ° C.
For 12 hours and in an autoclave at a temperature of 12
The presence or absence of blocking between the contact coatings when placed in steam at 1 ° C. for 1 hour was observed.

Heat resistance The presence or absence of abnormalities when kept in air at a temperature of 125 ° C. for 4 hours was observed.

Alkali resistance The presence or absence of abnormalities when immersed in a 3.5% aqueous solution of caustic soda at a temperature of 70 ° C. for 1 hour was observed.

Weather resistance It was left outdoors and observed for abnormalities.

<Results> The results are shown in Table 1.

Claims (2)

(57) [Claims] 1. A polyester product (a1) selected from the group consisting of a β-methyl-δ-valerolactone-based polyester polyol and a 3-methyl-1,5-pentanediol-based polyester polyol.
A layer of a polyurethane resin (A) which is a reaction product with 4,4'-methylenebis (cyclohexyl isocyanate) (a2) is provided as a primary coating layer, and a polyacryl polyol (b1) and a polyacryl polyol (b1) are further formed on the primary coating layer. A surface-coated glass product having a configuration in which a layer of a thermosetting acrylic melamine resin (B) which is a reaction product with an alkylated melamine (b2) is provided as a secondary coating layer. 2. A polyurethane resin (A) as a primary coating layer
Has a thickness of 5 to 100 μm, and the thickness of the layer of the thermosetting acrylic melamine resin (B) which is the secondary coating layer is 2 to 20 μm.
2. The surface-coated glass product according to claim 1, wherein the thickness is in the range of 10 to 1 .mu.m.