JPH01199320A - Surface treating device for magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve a calender treatment of a high temp. and high pressure and the surface treating speed of a tape by using a specific thermosetting resin on the surface layer of an elastic roll. CONSTITUTION:A calender section has the elastic roll which has the surface layer consisting of the thermosetting resin obtd. by bringing a bis(2-oxazoline) compd. and an arom. compd. having at least two amino groups into reaction. The bis(2-oxazoline) compd. is exemplified by the compd. expressed by the formula I. In the formula I, R denotes an intercarbon bond or bivalent hydrocarbon group; R<1>-R<4> respectively denote hydrogen, alkyl group or aryl group. The surface treatment at and under the high temp. and high pressure is thereby enabled and the surface treating speed of the tape is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a surface treatment apparatus during the manufacturing process of magnetic recording media.

BACKGROUND ART In general, magnetic recording media such as magnetic tapes are manufactured by applying a magnetic paint consisting of a magnetic material, various additives, and a binder onto a base film, and then applying a coating to smooth the surface of the magnetic layer and improve the magnetic density. Manufactured by calendering with rolls. In order to obtain a high-performance magnetic tape with a smooth magnetic layer surface and a high packing density, it is preferable that the surface temperature and linear pressure of the roll be as high as possible. In order to increase the surface temperature and linear pressure, a crosslinked polyesteramide obtained by reacting a bis(2-oxazoline) compound and a nocarboxylic acid in the presence of a phosphite is used as the color for the surface of the roll that contacts the magnetic recording medium. It has been proposed to use a thermosetting resin as the main component (JP-A-59-124028
(Japanese Patent Application Laid-Open No. 62-40618). However, recently there has been a strong demand to increase processing speed to improve productivity, and this has made it necessary to process at higher temperatures and pressures.
There is a growing demand for products that can withstand high pressure. In this respect, the above-mentioned roll cannot be used at a linear pressure of 250 kg/cm and at a temperature of 110° C. or higher because the surface hardness significantly decreases or the roll deforms.

Problems to be Solved by the Invention An object of the present invention is to provide a surface treatment apparatus for a magnetic recording medium, which is equipped with an elastic roll having a surface layer that can withstand higher temperatures and pressures.

Means for Solving the Problems The present inventor has been researching for many years on a method for producing thermosetting resins using a bis(2-oxacillin) compound and at least two It was discovered that when a roll made of a thermosetting resin obtained by reacting an aromatic compound having an amino group is used in a calendering device, the surface of the roll can be treated at a high temperature of 110°C or higher and at high pressure. Based on this knowledge, we have completed the present invention.

That is, the present invention provides an apparatus for manufacturing a magnetic recording medium that is provided with a calender section for surface-treating the magnetic recording medium, in which the calender section comprises a bis(2-oxazoline) compound and an aromatic compound having at least two amino groups. The present invention relates to a surface treatment apparatus for a magnetic recording medium, characterized by comprising an elastic roll having a surface layer of a thermosetting resin obtained by reacting a compound.

In the present invention, the thermosetting resin used as the roll surface layer contains a bis(2-oxazoline) compound and at least 2
It can be obtained by reacting aromatic compounds having 2 amino groups. Here, the bis(2-oxazoline) compound has the general formula [wherein R represents a carbon-carbon bond or a divalent hydrocarbon group, and R1, R2, R3, and R4 are hydrogen, an alkyl group, or an aryl group, respectively. shows. ] When R is a hydrocarbon group, specific examples include an alkylene group, a cycloalkylene group, and an arylene group.

As a specific example of such a bis(2-oxazoline) compound, when R is a carbon-carbon bond, for example, 2.2゛-bis(2-oxazoline)
-oxazoline), 2,2°-bis(4-methyl-2-
oxazoline), 2,2°-bis(5-methyl-2-oxacillin), 2,2゛-bis(5゜5“-dimethyl-
2-oxacillin), 2,2゛-bis(4,4,4°,
4'-tetramethyl-2-oxazoline) and the like. Further, when R is a hydrocarbon group, for example, 1,2-bis(2-oxazolin-2-yl)ethane, 1,4-bis(2-oxazolin-2-yl)butane,! , 6-bis(2-oxazolin-2-yl)hexane, 1.8-bis(2-oxazolin-2-yl)octane, 1.4-bis(2-oxazolin-2-yl)cyclohexane, 1.2 -bis(2-oxazoline-2-
yl)benzene, 1,3-bis(2-oxazoline-2
-yl)benzene, 1,4-bis(2-oxazoline-
2-yl)benzene, 1,2-bis(5-methyl-2-
Oxazolin-2-yl)benzene, 1,3-bis(5
-methyl-2-oxazolin-2-yl)benzene, 1
．． 4-bis(5-methyl-2-oxazolin-2-yl)benzene, l,4-bis(4,4'-dimethyl-2-
Examples include oxazolin-2-yl)benzene. These can be used alone or in combination of two or more. Among the above, 1,3-bis(2-
xacillin-2-yl)benzene, l,4-bis(2
-xacillin-2-yl)benzene is preferred.

Examples of aromatic compounds having at least two amino groups include compounds in which two amino groups are bonded to one benzene ring, polycyclic compounds in which two or more amino groups are bonded to one benzene ring, or compounds in which two or more amino groups are bonded to one benzene ring. Examples include combinations of two or more. Specific examples include o-, m- and p-
phenylenediamine, 2.4-)lylenediamine, 2
．． 3-) Luylene diamine, 2.5-) Luylene diamine, 4,4゜-diaminobiphenyl, 3.3゜-dimethoxy-4゜4゜-diaminobiphenyl, 4.4゜-diamino-triphenylmethane, 3.3'-dimethyl-4,
4°-biphenyl, 2.2′, 5.5°-tetrachloro-4°4°-diaminobiphenyl, 4.4°-methylenebisaniline, 4.4′-methylenebis(2-chloroaniline), 2. 2-bis[4-(4-aminophenoxy)phenylcopropane, 1.3-bis(4-aminophenoxy)benzene, 1.3-bis(3-aminophenoxy)benzene, 3,4°-diaminodiphenyl ether, Examples include 4,4°-diamino-diphenyl sulfide. These can be used alone or as a mixture of two or more.

Among the above, 4.4°-methylenebisaniline, 4
．． 4°-methylenebis(2-chloroaniline).

1.3-bis(4-aminophenoxy)benzene, 3°4°-diaminodiphenyl ether, 4,4°-diaminodiphenyl sulfide, 2.2-bis[4-(4-aminophenoxy)phenyl]propane, etc. are preferred. .

The amount of the aromatic compound having at least two amino groups is about 1,
It is preferably 25 mol or less, particularly about 1 to 0.25 mol.

The thermosetting resin used in the present invention can be obtained by reacting a bis(2-oxacillin) compound with an aromatic compound having at least two amino groups.

Vol, 3. No, 1. pp, 35-39 (1
972) and [Lecture on Polymerization Reactions 7, Ring-Opening Polymerization ■, pp, 1
It is preferable to use an oxazoline ring-opening polymerization catalyst such as that described in Kagaku Dojin (1973J), 59-164, since the reaction temperature can be lowered and the reaction time can be shortened. Specific examples include strong acids, sulfonic acid esters, sulfuric esters, organic halides having at least one halomethyl group in the molecule, and Lewis acids.

Examples of strong acids include oxoacids such as phosphoric acid, sulfuric acid, and nitric acid; mineral acids such as hydrochloric acid, hydrobromic acid, hydroiodic acid, and hydrogen acids such as hydrogen sulfide; and mineral acids such as phenylphosphoric acid and methanesulfonic acid. acid, benzenesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, naphthalene-α
Examples include organic acids such as -sulfonic acid, naphthalene-β-sulfonic acid, sulfanilic acid, and phenylsulfonic acid.

Examples of the sulfonic acid ester include methyl p-toluenesulfonate, ethyl p-toluenesulfonate, p-
Examples include n-butyl toluenesulfonate.

Examples of sulfuric esters include dimethyl sulfate and diethyl sulfate.

Preferred examples of organic halides are monohaloalkanes and polyhaloalkanes, such as, for example,
Examples include methyl iodide, butyl chloride, butyl bromide, n-hexyl bromide, butyl iodide, lauryl bromide, n-octyl bromide, stearyl bromide, allyl bromide, and ethane tetrabromide.

Further, other preferable specific examples of the organic halides mentioned above include benzyl bromide, monohalomethylbenzene such as p,p'-dichloromethylbenzene, and polyhalomethylbenzene.

Examples of Lewis acids include aluminum chloride, stannic chloride, vanadium chloride, and vanadyl chloride.

Examples include boron trifluoride etherate.

These catalysts can be used alone or in a mixture of two or more, and have a catalyst content of about 0.05 to It is used in a range of 3% by weight, preferably in a range of about 0.1 to 1% by weight.

In order to manufacture a roll having the above-mentioned thermosetting resin as a surface layer, the melted resin raw material is heated to a temperature of 80°C or higher, preferably at 80°C or higher, although it depends on the catalyst used, the amount used, and the resin raw material. 100-300°C, particularly preferably 10
Examples include a method of pouring into a roll manufacturing mold preheated to 0 to 200°C, continuing heating, and curing. Also,
Molding can also be advantageously carried out by so-called rotational molding. Alternatively, a melted resin raw material may be applied to the surface of a metal roll to a constant thickness by an appropriate means, and then heated and cured.

A thermosetting resin obtained by reacting a bis(2-oxazoline) compound with an aromatic compound having at least two amino groups may contain a reinforcing material and/or a filler. The reinforcing material is preferably a fiber reinforcing material used in ordinary fiber reinforced resins. Specifically, such fiber reinforcement materials include inorganic fibers such as glass fiber, carbon fiber, quartz fiber, ceramic fiber, zirconia fiber, boron fiber, tungsten fiber, molybdenum fiber, stainless steel fiber, beryllium fiber, and asbestos fiber, cotton, flax, hemp, jute,
Examples include natural fibers such as sisal, heat-resistant organic synthetic fibers such as polyamide fibers, and polyester fibers. Further, the surface of these fiber reinforcing materials may be previously treated with, for example, borane, silane, galan, aminosilane, etc., in order to improve adhesiveness with resin. These fiber reinforcing materials can be used alone or in combination of two or more.

Further, the shape of these fiber reinforcing materials is not limited at all, and may be used in the form of, for example, a string, a mat, a tape, short fibers cut to a certain size, or the like.

The fiber reinforced material may have a composite shape of these.

The blending amount of the fiber reinforcing material is appropriately selected depending on, for example, the melt viscosity of the resin raw material containing the catalyst, the type of reinforcing material used, its form, the use of the reinforced resin as a product, etc.
It is usually on the order of about 3 to 95% by weight, preferably about 5 to 80% by weight, based on the resin feedstock containing the catalyst.

Any filler that has been conventionally used in the field of synthetic resin molding can be used. Specific examples include oxides such as silica, alumina, and titanium oxide; hydroxides such as aluminum hydroxide; carbonates such as calcium carbonate and magnesium carbonate; silicates such as talc, clay, glass peas, and bentonite; Examples include carbon such as carbon black, metal powder such as iron powder, and aluminum powder. The blending amount of such filler is also selected as appropriate in the same manner as in the case of fiber reinforcement, but is usually about 3 to 95% by weight, preferably about 10 to 80% by weight, based on the resin raw material.
is within the range of

When used as a calender roll, there is a problem of fine dust adhering to the surface, but in order to prevent this, it is preferable to add Ketchen black, which is a type of carbon black. For this purpose, about 0.1-1% of Ketschen black is added to the amount of resin.

Furthermore, in addition to the above-mentioned fiber reinforcing materials and fillers, arbitrary additives such as stabilizers, internal mold release agents, pigments, flame retardants, etc. used in normal thermosetting resin molding may also be used.

In order to contain the above-mentioned fiber reinforcing materials and fillers, for example, bis(2-oxazoline), which is the above-mentioned reactant, is added.
A compound, an aromatic compound having at least two amino groups, a catalyst, and optionally a mixture of the above-mentioned substituted compounds, preferably a homogeneous mixture obtained by melting these, and a reinforcing material and/or a filler are mixed into the resin raw material. Alternatively, the reinforcing material and/or filler may be impregnated with the above mixture and then heated.

The rolls thus obtained are arranged at appropriate intervals as shown in FIG. 1, for example. This figure shows a calender unit that is a surface treatment device for magnetic recording media.

In the figure, l is a magnetic tape, 2 is a guide roll, 3°4 is a calendar roll, 5 is a hydraulic cylinder, 6 is a rod, and 7
8 indicates a bearing, and 8 indicates a frame.

The magnetic tape 1 runs in an S-shape between five rolls.

Among the five rolls, the lowest roll is pivotally supported by the frame 8 and rotationally driven by an external drive system (not shown). On the other hand, the uppermost roll is rotatably supported by a bearing 7 fixed to a rod 6 of a hydraulic cylinder 5 attached to a frame 8. The three rolls inside are rotatably supported by bearings that are movable only in the vertical direction.

When the top roll is lifted by the operation of the hydraulic cylinder, the three rolls inside are also lifted at predetermined intervals. Further, when the uppermost roll is lowered to a predetermined position, the three rolls are also lowered, so that the five rolls are brought into contact with each other under a predetermined pressure.

Among the three rolls inside, roll 3 is made of a metal roll with a mirror surface and has an internal heater (not shown) that controls the surface temperature at 40 to 200°C. The two elastic rolls 4 sandwiched between these metal rolls are the rolls used in the present invention, and the surface layer 4a is made of thermosetting resin. It is particularly preferable that the Shore hardness of this resin is D88 or higher, and in this case, the compressive strength (yield) is 15 kg.
f/+nm” or more, compressive elastic modulus is 340 kgf/m+
Shows a value of n' or more, and has a heat resistance of 18,5 kg/c
It shows a high value of 130°C or more in terms of deflection temperature under m' load.

Although the above example uses five rolls, the number can be changed as appropriate. Moreover, the number of metal rolls and elastic rolls can also be changed as appropriate.

EXAMPLES The present invention will be specifically explained below with reference to Examples.

Example 1 2.2-(1,3-phenylene)bis-2-oxazoline and methylenebisaniline were mixed at a molar ratio of 1.3:I, heated and dissolved, and then octyl bromide was added to the resin raw material. Add 0.4% of heavy equipment, pour this into a mold, and heat at 140°C.
After heating for 30 minutes, a cylindrical roll cover was obtained. After adjusting the inner diameter of this by cutting and polishing, it was shrink-fitted to a core and the surface was polished to obtain an elastic roll. The surface strength of this roll was 90 on Shore hardness. This roll and a metal roll were installed as shown in Figure 1, and an uncalendered videotape was calendered at a processing temperature of 120°C, a nip pressure of 250 kg/cm, and a tape running speed of 200 m/win. A tape with excellent strength was obtained.

Effects of the Invention In the present invention, a thermosetting resin obtained by reacting a bis(2-oxazoline) compound with an aromatic compound having at least two amino groups is used for the surface layer of the elastic roll. Due to its excellent heat resistance, high rigidity, and high hardness, it is possible to perform high-temperature and high-pressure calender treatment, which was previously impossible, and it is possible to increase the surface treatment speed of the tape.

[Brief explanation of the drawing]

FIG. 1 shows an example of the surface treatment apparatus of the present invention. In the figure, l・・・・・・・・・・・・Magnetic tape 2...
・・・・・・・・・・・・Guide roll 3・・・・・・
・・・・・・・・・Metal roll 4・・・・・・・・・・・・
......Elastic roll 4a...Surface layer 4b...Core body 5...
・・・・・・・・・Hydraulic cylinder〇・・・・・・・・・
・・・・・・・・・Rots door・・・・・・・・・・・・
・・・Bearing 8・・・・・・・・・・・・Frame. $1 Go to figure

Claims (1)

[Claims] In an apparatus for manufacturing a magnetic recording medium, which is provided with a calender section for surface-treating the magnetic recording medium, the calender section is obtained by reacting a bis(2-oxazoline) compound with an aromatic compound having at least two amino groups. 1. A surface treatment device for a magnetic recording medium, comprising an elastic roll having a surface layer of a thermosetting resin.