JPS6111226A - Attachment of discriminating label to surface of urethane - Google Patents

Abstract

PURPOSE:To prevent the separation of a label from the surface of urethane resin even under severe conditions by pressingly contacting a labelling urethane molding in uncompletely hardened nonfluidized state with an uncompletely hardened urethane cover. CONSTITUTION:Under the condition that a labeling urethane molding is in uncompletely hardened nonfluidized state, unreacted functional groups in the urethane molding react with unreacted functional groups in the surface of an urethane cover to form primary chemical bonds. For the urethane cover in uncompletely hardened state, in the case of rotation molding, reactions exceed after the coating of urethane, the viscosity is raised, and the urethane is completely hardened. Generally, however, when the viscosity becomes 10,000ps, preferably 100,000ps or more, the fluidity of the urethane is lost and the drooping phenomenon of urethane disappears even when rotation is stopped. Under the conditions, unreacted functional groups in the urethane molding react with unreacted functional groups in the urethane cover surface to form primary chemical bonds. Both the urethane materials under the condition are slightly pressed by stetcher rolls and allowed to stand naturally or heated as needed to obtain completely hardened and bonded moldings.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for attaching identification marks to the surface of a urethane cover provided on the outer surface of a marine hose, fender, flexible buoy, or the like.

Conventional technology For urethane hoses used at sea such as marine hoses,
It is necessary to attach an identification mark to identify it when in use.

Conventionally, the method used was to punch out or cut a fully cured urethane sheet to create an identification mark, and then use adhesive to adhere this to the fully cured urethane cover, which is the marine hose of the main unit.

However, signs bonded with this adhesive do not have sufficient adhesive strength, and when used under harsh conditions such as at sea, the adhesive deteriorates and has the disadvantage that durable adhesive strength cannot be restored. Additionally, there were problems such as the adhesive peeling off due to large deformation of the hose when a large load was applied.

For this reason, attempts were made to place a mold directly on the urethane cover and cast urethane in one piece, but due to the curved surface processing that had to be formed on the curved surface of the hose,
It cannot be molded properly.

Furthermore, in the method of directly painting the sign onto the surface of the urethane hose, the paint wears away during use, causing the identification sign to disappear.

In this way, an identification mark of at least 1 m/thickness or more is firmly attached to the hose surface, and it does not wear out during use, is durable under the harsh conditions of marine use, and is designed to withstand heavy loads. A technology for attaching a label that does not peel off even when the hose is deformed has not yet been developed.

II. OBJECTS OF THE INVENTION The purpose of the present invention is to solve the above-mentioned problems and to provide a urethane hose surface with a mark having a thickness that allows it to be used for a sufficiently long period of time even if it is worn out during use. Moreover, it is an object of the present invention to provide a method for attaching a label that is durable under the harsh conditions of marine use and does not peel off even when a hose is deformed under heavy loads.

■Specific structure of the invention The present invention involves pressing a urethane molded body for a sign in an uncompletely cured state that has lost its fluidity to an incompletely cured urethane cover (in the form of a hose), and then completely curing both urethane materials. This is a method of attaching an identification mark to a urethane surface.

Hereinafter, the content of the present invention will be explained in more detail.

The incompletely cured state in which the urethane molded product for marking has lost its fluidity means that the unreacted functional groups of the urethane molded product react with the unreacted functional groups on the urethane cover surface described below to form a primary chemical bond. Refers to the state in which it is formed, and in the case of urethane with a final hardness of 90'', the hardness is preferably 50 to 85.

If the hardness is less than 50, sufficient moldability as a marker cannot be achieved, and if the hardness exceeds 85, the adhesion to the urethane cover becomes poor as seen in the measurement results of later experiments, and the effect of the present invention is reduced. I can't.

When the urethane cover is not completely cured, in the case of rotary molding, which involves supplying urethane stock solution while rotating the hose core and smoothing it with a scraper, after the urethane is applied, the reaction progresses and the urethane viscosity increases. Generally, when the viscosity reaches 10,000 ps, preferably 100,000 ps or more, the urethane loses its fluidity and the urethane does not sag even after the rotation is stopped. This is the optimal state for the unreacted functional groups to react with the unreacted functional groups on the surface of the urethane cover to form -order chemical bonds.

That is, the urethane material for the sign is cast into a mold with a thickness of 3 to 5 cm, and about 24 hours later, while the tack remains in an incompletely cured state, the urethane material for the main body is cast for 4 hours after the final coating. It is in an incompletely cured state with no fluidity.

These two urethane materials are lightly pressed together using a stitcher roll, and then left to stand for 3 days, or heated if necessary, to be completely cured.

Representative examples of urethane, curing agent, etc. that can be used in the present invention are described below.

Urethane refers to urethane elastomer, and any urethane resin that has elasticity can be used in the present invention. Looking more closely, urethane consists of a urethane prepolymer and a curing agent, and if necessary, catalysts, colors, additives (anti-sag agents, fillers, plasticizers, light stabilizers, etc.) are added. You can.

The main components of the urethane prepolymer are polyol and polyinsyanate. Preols used in the present invention include polyether polyols such as polytetramethylene glycol, polyethylene glycol, and polypropylene glycol, olefin polyols such as polybutadiene polyol and polyisoprene polyol, adipate polyols, lactone polyols, and castor oil. Polyester polyols such as can be used. We consider water resistance and weather resistance for marine products.
Polyether-based polyolefins are preferred. Moreover, several kinds of these polyols can be combined as necessary.

Polyisocyanates include tolylene diisocyanate,
Diphenylmethane 4,4'-diisocyanate and its modified products, 1,5-naphthylene diisocyanate, bitolylene diisocyanate, inlon diisocyanate, xylene diisocyanate, etc. can be used.

Usually, the equivalent ratio of urethane prepolymer is (polyincyanate)/(polyol)=1.471 to 2.5/
1, preferably 1.871 to 2.2/1.

As a curing agent, -13,3'-dichloro-4,4-diaminodiphenylmethane: 4,4'-diaminodiphenylmethane, an amine curing agent such as tolylene diamine, 1,
4-butanediol, 1,6-hexanediol, 1.
5-bentanediol, diethylene glycol, and propene oxide or ethylene oxide derivative polyols such as ethylene glycol, glycerin, trimethylolpropane, or ethylenediamine;
Polyol-based curing agents such as polytetramethylene glycol and β-hydroxylethoxybenzene can be used. If necessary, several types of these curing agents may be used in combination.

Catalysts include metals commonly known as urethane catalysts (tin, lead, potassium, titanium, bismuth, nickel,
Cobalt, iron, calcium, magnesium, cadmium, mercury, etc.) salts, amine catalysts (generally tertiary amines),
An acidic catalyst such as carboxylic acid can be used, but depending on the combination of the urethane materials or the curing conditions, no catalyst may be used.

Of course, the urethane material described above only represents a part of the whole, and does not limit the urethane material used in the present invention.

Even if the urethane cover material and the urethane molded body for identification signs are not made of the same material (prepolymer, curing agent), it is possible to obtain strong adhesion through primary bonding through unreacted functional groups; It is preferable to use the same base material to obtain strength.

As the material of the mold for the identification mark, metal molds such as iron, copper, stainless steel, and aluminum, wood, silicone resin, etc. can be used. Preferably, urethane is in an uncured state, so silicone resin is preferable from the viewpoint of mold releasability.Also, when a mold is crimped together with a mold to adhere to a curved surface, if a metal mold is used, it has rigidity. Therefore, 9.
．． It is preferable to use a mold with a thickness of 5 cm or less.

Although the above-mentioned urethane is essentially a two-component urethane, a one-component urethane can also be applied to the present invention. - Liquid urethane can be roughly divided into moisture-curing urethane, ultraviolet-curing urethane,
It becomes heat decomposition hardening type urethane.

For example, some moisture-curing urethanes use - as the urethane prepolymer and use atmospheric moisture as a curing agent.

As the polyisocyanate for the urethane prepolymer, diphenylmethane-4,4'-diisocyanate is preferred from the viewpoint of reactivity and cost.

Furthermore, the reaction between incyanate groups and water generates carbon dioxide gas, which causes bubbles to be mixed in. Therefore, the N00% of the urethane prepolymer is preferably 3% or less, preferably 1% or less. Addition of gas absorbents is also effective.

In addition, UV-curable urethanes include those with acrylic terminals modified, and heat-decomposition-curing types include millable urethanes, blocked isocyanates, and the like. For example, in the case of millable urethane, a hydroxyl-terminated urethane prepolymer is cured with incyanate groups generated by thermally decomposing a dimer of tolylene diisocyanate at 150°C. Alternatively, for blocked isocyanate, incyanate groups are blocked with phenol diethyl malonate or the like, the blocking agent is dissociated under heating at around 160° C., and the resulting incyanate groups are cured. - It is possible to control the curing reaction of liquid urethane, and it is possible to attach identification marks in an incompletely cured state.

Of course, -liquid T-urethane and one-component urethane,
-Identification marks can be attached by combining liquid urethane and two-part urethane, or two-part urethane and two-part urethane. It is desirable to select a combination by taking into consideration the morphological reaction curing conditions of the urethane cover and identification mark.

The urethane for the identification mark is pressed onto the urethane cover in an incompletely cured state. However, immediately before fluidity is lost, for example at around 10,000 poise, the shape of the identification mark will collapse if it is released from the mold, so it is preferable to lightly press the identification mark together with the mold and allow it to react for a predetermined period of time.

On the other hand, when the identification mark is crimped after being released from the mold, if the final hardness is 90'', a suitable value is 50 to 85, and it is preferable that a slight surface tack remains.

Therefore, as a means to increase the tack during crimping, the crimping surface can be prepared using solvents such as toluene, xylene, n-hebutane, n-hexane, which do not or do not easily react with urethane functional groups, especially incyanate groups. , swab with benzene, methyl ethyl ketone, ethyl acetate, Cellsolve acetate, methylene chloride, trichlene, perchlorethylene, dimethylformamide, etc.
It is preferable to do so.

In order to further strengthen the primary bond between the urethane cover and the identification mark, it is preferable to dissolve the polyisocyanate in the solvent in an amount of 50% by weight or less, preferably 0.5 to 10% by weight. The polyisocyanate mentioned here includes, in addition to the above-mentioned polyisocyanate, a urethane adhesive containing a terminal isonate functional group or the above-mentioned urethane prepolymer, and if necessary, the above-mentioned urethane catalyst may be further added. preferable.

Whether swabbing with a solvent alone, a polyisocyanate-dissolved solvent, or a polyisocyanate-dissolved solvent with added catalyst, the urethane cover and the identification mark are directly or indirectly bound together. form and glue. Therefore, even if the method of the present invention is used, it is difficult to form a primary bond □ and it is difficult to obtain a durable and strong adhesive force, assuming that either the 6-rethane cover or the identification mark is completely cured. is characterized by the ability to obtain a strong adhesive force that is durable and can even lead to material destruction using a simple method.

The molding method for urethane cover material is described in Japanese Patent Publication No. 30-238,
As disclosed in Japanese Patent Application Laid-Open No. 53-56715.

In addition to the method of supplying urethane stock solution while rotating the hose core and smoothing it with a scraper, there are also methods such as spray coating and troweling.

The 0 rotation speed to finish the urethane cover thickness to at least 3 mm or more depends on the product diameter, but is 800φ to 1200φ.
φ is preferably 8 to 15 revolutions per minute. In addition, scrapers include plate-shaped rubber sponges, soft foams with a high closed cell ratio such as polyethylene foam, polyurethane foam, rubber plates with a hardness of 110 to 70, hard vinyl chloride, polyethylene, fluororesin, polystyrene, A, B.
In the case of zero-turn molding, which can use resin plates such as S, and thin metal plates such as stainless steel, copper, aluminum, iron, etc., after urethane is applied, the reaction proceeds and the viscosity of the urethane increases. Generally, when the viscosity reaches 10,000 ps, preferably 10,000 ps or more, fluidity is lost and the urethane sag disappears even when the rotation is stopped. It is preferable to stop the rotation when the urethane no longer drips, and lightly press the uncompletely cured identification mark into a predetermined position. In other words, it is best to attach the identification mark when the urethane reaction is as slow as possible. , -increases the frozen mass, leading to stronger adhesion.

■ Effects of the invention In the present invention, a urethane molded body for a sign is crimped in an incomplete state to a urethane cover with an incomplete effect, and then,
Since both urethane materials are completely cured, the unreacted functional groups of both urethane materials react and form -order chemical bonds.
During the destructive test, strong adhesion was achieved to the point of material failure.

In addition, since a mold with the identification mark formed thereon is used, this method allows the identification mark to be attached to the urethane surface as a floating identification mark with a clean shape and clear appearance.

In this way, since there is no adhesive layer in the present invention, there is no problem of deterioration of the adhesive material, and since the urethane cover and the urethane sign are made of the same material, they will not peel off even if the urethane cover is deformed by a large load. A method for attaching free identification marks to urethane surfaces has been obtained.

■ Specific examples <Example-1> Urethane prepolymer (trade name: Hypren L-Zoo Mitsui Nisso) prepared by adding and reacting about 2 moles of tolylene diisocyanate to 1 mole of polytetramethylene glycol having an average molecular weight of about 1500. ■) 100 parts of 3,3'-dichloro-4, which had been temperature-controlled to 80°C and 120°C in advance,
12.7 parts of 4'-diaminodiphenylmethane (trade name: Iharakyuamine MT, Ihara Chemical @) was added (Formulation-1).

After stirring and mixing for about 2 minutes, the mixture was cast into a silicone mold for identification marks, etc. After casting, the reaction temperature and reaction time were varied to produce urethane molded bodies for various incomplete effect labels.

These were lightly pressed using a stitcher roll to an incomplete effect urethane cover under different reaction conditions. After the urethane molded body for marking and the urethane cover were crimped together, they were allowed to stand for 7 days and a peel test was conducted to obtain Table 1. Hardness after 7 days is JIS
The hardness was 90 on the hardness meter. In the results, material failure is indicated by a 0 mark, partial material failure is indicated by a Δ mark, and interfacial peeling is indicated by an x mark throughout the table.

<Example-2> Adding a catalyst to Formulation-1 of Example-1, 0.
A similar test was conducted using a formulation in which 1 part was added, and Table 2 was obtained. However, the hardness of the urethane molded body for signs after 7 days is J
It was 90 on the IS hardness tester. The adhesive surface was swabbed with a toluene solution containing 5% by weight of crude MDI (Mitsui Nisso Urethane CR-200) dissolved in toluene.

In addition, for the peel test, cut the attached identification sign with a knife so that the adhesive interface is exposed, pinch the end of the identification sign with pliers,
The state of peeling was observed by hand.

<Example 3> The same urethane prepolymer, the same effect material, and the same catalyst as in Example 2 were used in the same amounts, and after stirring and mixing for about 2 minutes, the mixture was cast into a silicon mold for identification markers. After casting, the mixture was left at room temperature (20° C.) to produce urethane molded objects for markers in various cured states. At the same time, a test piece for hardness measurement (
A film with a thickness of 12 m) was prepared, and its hardness was measured over time using a JIS hardness meter (Type A) to obtain Figure 1. The hardness after 7 days was 89. After swabbing the urethane molded product with methyl ethyl ketone (MEK), the product was left to stand at room temperature using the above formulation, and then lightly pressed using a stitcher roll to the prepared urethane covers in various cured states. After press-bonding the urethane molded body for marking and the urethane cover, the urethane cover was left to stand naturally, and after 7 days or more had elapsed since both urethane materials were stirred and mixed, a peel test was conducted, and Table 3 was obtained.

<Example-4> In Example-3, the urethane molded body for marking and the urethane cover were left in an atmosphere of about 50°C to obtain various cured states. The hardness changes are as shown in Figure 2.
The hardness after 7 days was 90. Then, the adhesive surface of the identification mark was swabbed with a toluene solution containing 5% by weight of crude MDI (N00%: 30% by weight) (Mitsui Nisso, trade name: CR-200) dissolved in toluene. After stirring and mixing, both urethane materials were subjected to a peel test after 7 days or more had elapsed, and Table 4 was obtained.

From the results shown in Table 1, Table 2, Table 3, and Table 4, the optimum incompletely cured state of the urethane molded object for signs and the urethane cover was selected and crimped, and then completely cured. It can be seen that the very strong adhesion of the urethane material can be changed.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the change in hardness over time at room temperature of the urethane molded product for marking of Example 3. FIG. 2 is a graph showing the change in hardness over time at 50° C. of the urethane molded product for marking of Example 4.

Claims (1)

[Claims] A method for attaching an identification sign to a urethane surface, which comprises pressing a urethane molded body for a sign in an uncompletely cured state that has lost its fluidity to an uncompletely cured urethane cover, and then completely curing both urethane materials. .