JPH0266787A - Sliding sheet for cassette - Google Patents

Abstract

PURPOSE:To improve the antistatic function of a silicone compound in a sliding layer by forming a sliding layer with a silicone resin and a silicone compound having compatibility, and executing a neutralizing processing for the silicone compound with an acid and a base. CONSTITUTION:The silicone resin and the silicone compound having the compatibility are held in a compatible condition up to the stage of coating cure, they are applied on a plastic sheet 1 in such a condition, the silicone resin in the compatible condition is cured, a sliding layer 2 is formed, and next,the silicone compound is neutralized by the acid and the base. Thus, the antistatic function of the sliding layer 2 is improved, and without degrading running durability caused by static electricity and stably a tape can be made to run in a condition to be inserted into a cassette.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sliding sheet for cassettes that is incorporated into cassettes such as audio cassettes and video cassettes.

[Conventional technology]

Cassettes such as audio cassettes and video cassettes are equipped with sliding sheets for reducing the friction between the tape and the inner wall of the case when the magnetic tape is running, thereby stabilizing the running of the tape. In this type of cassette, both the left and right sides of the wound tape rotate while contacting the surface of a sliding sheet provided on the inner wall of the case, thereby ensuring smooth running of the tape and prevention of uneven winding. ing. The sliding sheet that exhibits these functions not only has good sliding properties with the side surface of the rolled tape, but also has antistatic properties to prevent deterioration in running sustainability due to static electricity generated by contact with the tape. Performance is also required.

[Problem that the invention seeks to solve]

For the purpose of imparting such properties of both slipperiness and antistatic properties, conventional techniques have been disclosed in which a silicone resin and an antistatic agent are applied to a plastic sheet in a mixed state or each is applied separately. (Japanese Patent Application Laid-Open No. 58-146065). However, when applying the silicone resin and the antistatic agent in a mixed state as described above, the silicone resin and the antistatic agent are hydrophobic and hydrophilic, respectively, and are inherently incompatible. However, by diluting the above-mentioned liquid mixture with a solvent, both are completely dissolved and used. However, when such a solution is used, the two separate as the solvent decreases during the drying process after application.
A uniform slipping layer cannot be obtained, and the antistatic agent blooms on the surface of the slipping layer, resulting in stickiness when administered orally. Therefore, the original performance of the slipping layer cannot be obtained. In addition, when applying the silicone resin and the antistatic agent separately, the slipping layer has a two-layer structure.
Only the properties located on the surface layer side are exhibited, and it is not possible to exhibit both properties of slipperiness and antistatic properties at the same time.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a sliding sheet for a cassette that has both slipperiness and antistatic properties.

[Means for Solving the Problems] In order to achieve the above object, the sliding sheet for cassettes of the present invention is a sliding sheet for cassettes in which a sliding layer is formed on at least one side of a plastic sheet, and the sliding sheet has a sliding layer formed on at least one side of a plastic sheet. has a structure in which the following components (A) and (B) are used as active ingredients, and after layer formation, component (B) is neutralized with an acid or base.

(A) Silicone resin.

(B) A silicone compound that can be neutralized with an acid or base.

[Effect]

That is, this invention maintains a silicone resin (which essentially has slipperiness) and a compatible silicone compound in a compatible state until the stage of coating and curing, and in this state, coats the plastic sheet onto the plastic sheet. By curing the compatible silicone resin to form a layer and then neutralizing the silicone compound with an acid or base, the antistatic function is greatly improved. Problems such as separation do not occur, and the sliding layer exhibits stable sliding properties and antistatic properties over a long period of time.

The sliding sheet for cassettes of the present invention is obtained using a plastic sheet as a base material, a silicone resin (component A), and a silicone compound that can be neutralized with an acid or a base (component B).

The above plastic sheets include polyethylene terephthalate, polybutylene terephthalate polycarbonate, etc.
1-, polyamide, polypropylene, triacetylcellulose, and the like. Note that although these plastic sheets are transparent, opaque plastic sheets may be used depending on the case.

Examples of the silicone resin that is component A include polydimethyl silicone, polymethylphenyl silicone, and the like.

As the silicone compound which is the above-mentioned B component, amino-modified silicone compounds and carboxyl-modified silicone compounds are suitably used, and specifically, the following formulas (1) to (I
Examples include those shown in V).

CH3CH3 The silicone compounds as component B may be used alone or in combination.

The blending ratio of the silicone resin (A) which is the above A component and the silicone compound (B) which is the B component is A/
It is preferable to set the ratio of B=10015 to 100/100. That is, the silicone compound of component B is 1
If the amount exceeds 0.00 parts by weight (hereinafter abbreviated as "parts"), the slipping layer becomes sticky and the slipperiness decreases, while if it is less than 5 parts, the antistatic properties become insufficient.

Note that, if necessary, the slipping layer may be formed using other component materials other than those mentioned above.

The sliding sheet for cassettes of the present invention uses the above-mentioned materials,
For example, it is manufactured as follows. That is, the above A
A compatible mixture of a silicone resin as a component and a silicone compound as a component B is applied to at least one side of a plastic sheet (including spraying, roll coating, etc.), and is cured by heat, ultraviolet rays, or radiation irradiation to form a phase, and then this is applied. It can be produced by neutralization treatment such as immersion in an acid or base solution. In this case, since the coating layer is as thin as 0.01 to Ig/rrf, a low-viscosity silicone resin is usually used or diluted with a solvent and then applied, the solvent is evaporated, and then the above-mentioned heat, ultraviolet rays, etc. is irradiated to cure the silicone resin, and then neutralized as described above.

In the sliding sheet for cassettes obtained in this way, the sliding layer exhibits the inherent slipping properties of silicone resin, and the antistatic function of the silicone compound in the sliding layer is greatly improved by neutralization treatment. These properties are less likely to deteriorate over time.

〔Effect of the invention〕

As described above, in the sliding sheet for cassettes of the present invention, the sliding layer contains as active ingredients a silicone resin that inherently has slipping properties and a silicone compound whose antistatic function is greatly improved by neutralization treatment. Because it is configured
In a state where the tape is incorporated in a cassette, it is possible to run the tape stably and without deterioration of running continuity due to static electricity.

Next, examples will be described together with comparative examples.

[Example 1] To 100 g of toluene, silicone resin (KS-770A, manufactured by Shin-Etsu Silicone Co., Ltd.) Log, 0.09 g of catalyst (manufactured by Shin-Etsu Silicone Co., Ltd., PL-8), and amino-modified silicone represented by the following formula. 1 g of oil was dissolved.

CH3CH3 H2N-c, H, -5io-5i-CH3CHff C
H3 Next, this solution was applied to a 50 μm thick film made of polyethylene terephthalate with a solid content of 0.1 g.
/n(), and was cured by heating at a temperature of 140°C for 2 minutes to form a slipping layer.

No violent phase separation of the coating occurred during the curing process. Furthermore, the sheet thus produced was immersed in hydrochloric acid having a concentration of 5N for 10 seconds, and dried at 100°C for 10 minutes to obtain the intended sliding sheet for cassettes. The obtained sliding sheet for transparent cassettes is shown in FIGS. 1 and 2. In the figure, 1 is a sheet made of polyethylene terephthalate, and 2 is a slipping layer.

[Comparative Example 1] No immersion in hydrochloric acid. A sliding sheet for a cassette was obtained in the same manner as in Example 1 except for the above.

[Example 2] The amino-modified silicone oil was replaced with one represented by the following formula, and the hydrochloric acid with a concentration of 5N was replaced with nitric acid with a concentration of 5N. A sliding sheet for a cassette was obtained in the same manner as in Example 1 except for the above. Note that no violent phase separation of the coated material occurred during the curing process.

[Comparative Example 2] No immersion in nitric acid. A sliding sheet for a cassette was obtained in the same manner as in Example 2 except for the above.

[Example 3] The amino-modified silicone oil was replaced with one represented by the formula below, and the hydrochloric acid with a concentration of 5N was replaced with an aqueous solution of caustic soda with a concentration of 5N, and the mixture was immersed for 10 seconds and diluted with water at 20°C for 10 seconds.
Washed with water for a minute. A sliding sheet for a cassette was obtained in the same manner as in Example 1 except for the above. Note that no violent phase separation of the coated material occurred during the curing process.

[Comparative Example 3] It was not immersed in a caustic soda aqueous solution. A sliding sheet for a cassette was obtained in the same manner as in Example 3 except for the above.

[Comparative Example 4] 1 g of the amino-modified silicone oil used in Example 1 was mixed in advance with 5N hydrochloric acid Log, and further heated to a temperature of 90°C.
The mixture was heated for 1 hour to volatilize excess hydrochloric acid and water, thereby producing a silicone oil in which the amino groups were converted into hydrochloride. 1 g of this silicone oil was used in place of the amino-modified silicone oil. A sliding sheet for a cassette was produced in the same manner as in Example 1 except for the above. However, the temperature is 140°C
During the curing process for X2 minutes, the coated material underwent violent phase separation, and the resulting cassette sliding sheet did not have a good appearance.

Surface resistance values were measured using the above Example products and Comparative Example products, and a running property test was conducted. The results are shown in the table below. In addition, the measurement of surface resistance value and the running property test were performed as follows.

<Surface Resistance Value> The surface resistance of the sliding layer of each cassette sliding sheet was measured at a temperature of 20° C. and a humidity of 50% RH.

<Runability test> A sliding sheet for cassettes was installed in a C-90 audio cassette so that the sliding layer was in contact with the magnetic tape (two sheets were installed for each cassette), and the speed was 400 cm/
sec is one cycle of winding and unwinding.
0 cycles were repeated continuously, and occurrence of winding disorder due to static electricity was visually observed.

FIG.

1...Plastic Sea 1-2...Slip layer patent applicant: Nitto Electric Industry Co., Ltd. Representative Patent Attorney Yukihiko Nishifuji From the above results, the surface resistance of the example products is higher than that of the comparative example products. It was found that the antistatic property was excellent because of the low value, and the results of the running test were also good.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a sliding sheet for a cassette obtained in an embodiment of the present invention, and FIG.

Claims (2)

[Claims] (1) A sliding sheet for a cassette in which a sliding layer is formed on at least one side of a plastic sheet, wherein the sliding layer contains the following components (A) and (B) as active ingredients, and after forming the layer, (B) A sliding sheet for cassettes, characterized in that the ingredients are neutralized with an acid or a base. (A) Silicone resin. (B) A silicone compound that can be neutralized with an acid or base. (2) The sliding sheet for a cassette according to claim (1), wherein the component (B) is an amino-modified silicone compound.