JP2510276Y2 - Paper tube - Google Patents

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

The present invention relates to a paper tube in which impurities contained in the paper tube are not substantially transferred to a molded product such as a thread, a knitted fabric or a film wound around the paper tube.

[0002]

[Prior art]

Molded products such as yarns, knitted fabrics, and films are often wound around paper tubes due to transportation and storage. However, since the paper tube is made of pulp as a raw material, it contains water, oil, sizing agent and various other impurities.

[0003]

[Problems to be solved by the device]

When a molded product such as a thread, a knitted woven fabric, or a film is wound around such a paper tube and stored, impurities contained in the paper tube leak or are gasified and transferred to the molded product. Performance will be degraded. Among these properties, a molded product having hydrophilicity, that is, a molded product subjected to a hydrophilization treatment is greatly affected, and the hydrophilic property of the molded product decreases with storage time. The hydrophilicity is evaluated by the time it takes for a water drop to drop on the surface of a sample and for the water drop to permeate the knitted fabric. The shorter the time, the better the performance. The film drops water drops on the film surface and is evaluated by the contact angle of the water drops at that time. The smaller the angle, the better the performance. It is considered that the reason for the decrease in hydrophilicity is that hydrophilic groups (carboxyl group, carbonyl group, hydroxyl group, amide group, etc.) on the surface of the molded product are contaminated by leakage of impurities. It is an object of the present invention to provide a paper tube that does not substantially deteriorate the performance of the molded product such as yarn, knitted fabric, and film even if it is wound around the paper tube and stored. It is a thing.

[0004]

[Means for Solving the Problems]

That is, according to the present invention, in the rolled roll of rolled molded product that has been subjected to the hydrophilization treatment, the winding surface portion has an ethylene copolymerization amount of 30%.
The paper tube is coated with an ethylene-vinyl alcohol polymer having a content of ˜70 mol% and a saponification degree of 80 mol% or more.

In the present invention, the term “hydrophilized molded article” means “molded article having a hydrophilic group such as a carboxyl group, a carbonyl group, a hydroxyl group or an amide group attached to the surface of a molded article such as a thread, knitted fabric or film. Product ”, and the hydrophilic treatment is performed by a known method. Examples thereof include physical methods such as plasma treatment, corona treatment, ozone treatment, and flame treatment on the surface of the molded product, and chemical treatment with a chemical having a carboxyl group, a carbonyl group, a hydroxyl group, or an amide group.

The ethylene-vinyl alcohol copolymer according to the present invention will be described. The copolymer has an ethylene copolymerization amount of 30 to 70 mol%. If the copolymerization amount is less than 30 mol% or more than 70 mol%, the gas barrier property is deteriorated, and impurities (including gasified substances) leaked from the paper tube when the molded product is wound around the paper tube. ) Cannot be blocked, and the hydrophilic property of the molded product is deteriorated. Further, such a copolymer can be obtained by saponifying an ethylene-vinyl acetate copolymer, and the saponification degree at that time is
It must be 80 mol% or more. When the degree of saponification is less than 80 mol%, the crystallinity of the coating film made of the copolymer is small, the moldability of the coating film is poor, and the dimensional stability is poor. Further, the coating film easily contains oil in the air and swells, and the surface of the coating film is highly tacky and sticky, resulting in poor handleability.

The coating thickness of the copolymer is preferably 10 to 100 μm. When the thickness is less than 10 μm, the tensile strength of the coating is insufficient, and the coating may be broken when the coating is produced or when the molded product is wound around the coated paper tube. On the other hand, the thickness is
If it exceeds 100 μm, the coating becomes hard and it becomes difficult to apply the coating to the paper tube. More preferable coating thickness is 40
-60 μm.

The characteristic of the copolymer is that it has an excellent gas barrier property and that it does not substantially contain additives (plasticizer, etc.). The most typical method of applying a coating film of the copolymer to a paper tube is a method of winding a film made of the copolymer. However, with this method, there arises a problem of how many layers of the film are wound and how much in the lengthwise direction of the paper tube the film is wound. However, this problem is solved by the following. To do.

First, the number of layers of the film to be wound depends on the thickness of the film, but in general, the purpose can be achieved by winding one or more layers on the entire outer surface of the paper tube. In the case of less than one layer, for example, when partially coated, impurities (including gasified ones) leak out from the exposed portion of the paper tube that is not coated with the copolymer and contaminates hydrophilic groups of the molded product. As a result, the hydrophilic performance of the molded product is reduced. Next is how much the film is wound along the length of the paper tube. This depends on the width of the molded product wound around the paper tube, but at least the portion around which the molded product is wound may be coated with a coating film of the copolymer. If the coating is shorter than the width of the molded product, impurities (including those that have become soot) leak from the surface of the paper tube and contaminate the hydrophilic groups of the molded product, reducing the hydrophilic performance of the molded product. Will be

FIG. 1 is a perspective view of an example of the paper tube of the present invention, and FIG. 2 is a perspective view of another example of the paper tube of the present invention. FIG. 1 shows the winding surface only coated with an ethylene-vinyl alcohol copolymer, and FIG. 2 shows the entire outer surface of the paper tube other than the winding surface coated. Figure 3 is the first
It is an example figure when a molded product is wound up on the paper tube of the figure.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a paper tube of the present invention.

FIG. 2 is a perspective view showing another example of the paper tube of the present invention.

FIG. 3 is a perspective view of a paper tube of the present invention in which a molded product is wound up.

[Explanation of symbols]

 1: Paper tube 2: Ethylene-vinyl alcohol copolymer coating 3: Molded product

Claims (1)

(57) [Scope of utility model registration request] 1. A hydrophilicity-treated roll of rolled molded product, the winding surface portion of which is coated with an ethylene-vinyl alcohol copolymer having an ethylene copolymerization amount of 30 to 70 mol% and a saponification degree of 80 mol% or more. Is a paper tube.