JPS5851551B2 - Insatsunitekishitafushiyokufu - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the construction of a nonwoven fabric suitable for printing.

Non-woven fabrics suitable for printing here are used for textiles such as underwear, sweaters and other clothing, bedding, sheets or curtains, and can be used to mark the quality of the fabrics, composition marks, information labels, name labels, tablecloths, and books. For interior decoration such as covers, ribbons, and wallpaper, for building materials,
It refers to nonwoven fabrics suitable for various uses such as packaging and household use.

Conventionally, labels for clothing have been embroidered or printed on woven fabric, and recently those printed on general non-woven fabric. In the latter case, the surface is relatively linear and has poor smoothness, resulting in ink stains and “
It has the disadvantage that non-uniform adhesiveness tends to occur and printability is poor.

As shown in FIG. 1, the structure of a nonwoven fabric used as a conventional clothing label is composed of fibers 1 and a binder 2 that binds the fibers together.

The surface of the above conventional nonwoven fabric is very sparse, and since the binder 2 is present, the printing ink 3 "glues" unevenly, making it difficult to obtain clear, thin prints.

In addition, synthetic rubbers such as SBR and NBR and synthetic resins such as acrylic esters are generally used as binders.
These resins are more resistant to solvents than fibers.

It has poor abrasion resistance and weather resistance, and causes problems such as fuzzing, deformation, hardening, peeling of printing, and discoloration during repeated washing and wearing. As textile products have become more diverse, various chemicals and methods have come to be used for cleaning, and these binders may be subject to swelling or dissolution effects, causing damage to nonwoven fabrics.

In order to eliminate such drawbacks of conventional clothing labels and obtain a nonwoven fabric that is durable and suitable for obtaining clear display by printing, the present invention aims to solve the problems of conventional clothing labels by bonding fibers together without using a binder. A binder-free nonwoven fabric is used as a nonwoven base material for printing, and the web-forming fibers are impregnated with an appropriate amount of solvent or plasticizer in advance by dropping or spraying, and then dispersed more uniformly on the fibers using a carding machine. After forming a web, it is heated and pressed through a pair of heated rolls to activate the solvent and bond the fibers together to form a nonwoven fabric.

The following table shows examples of combinations of fibers forming these nonwoven fabrics and solvents or plasticizers that have a dissolving or swelling effect on the fibers.

In general, these binder-free nonwoven fabrics have better mechanical strength than conventional nonwoven fabrics using binders, and the present invention uses a binder-free nonwoven fabric to provide optimal mechanical strength and flexibility for clothing labels. 2-0.4? It is composed of a binder-free nonwoven fabric with an apparent density of /crtl.

The apparent density is 0.4? If it is larger than /crtl, the intersections between the fibers of the nonwoven fabric, that is, the welded parts, will be excessive, reducing the slippage between the fibers, giving a paper-like hard feel, and reducing tear resistance. Defects such as easy tearing appear.

On the other hand, when the apparent density is lower than O-2fl/cA, the fibers are bonded using the fiber's activity due to heat pressure, so there are many intersections on the projection plane, but there are some intersections that do not touch in the cross-sectional direction. If the number of particles increases, it will not actually serve as a bonding point, resulting in insufficient strength and causing fuzzing, flaking, etc.

In addition to the above points, sufficient consideration must be taken when printing clothing labels using nonwoven fabric.

In other words, in order to keep up with the diversification of printing inks and the progress of printing technology, various conditions are required for the surface of the nonwoven fabric that is the printing surface.

In general, the surface of nonwoven fabrics and textiles has an uneven and porous structure, and in order to obtain a good printing surface, very strict requirements are placed on the properties of the printing ink, especially the viscosity.

If the viscosity of the printing ink is low, it will easily stain, whereas if the viscosity is high, the surface will become uneven, resulting in uneven ink "spreading".

Therefore, it is difficult to obtain uniform and clear printing simply by adjusting the density of the nonwoven material as described above in order to obtain a suitable printing surface.

Furthermore, the affinity between the printing ink and the nonwoven fabric that is the printing surface must also be considered as an important factor.

A smooth printing surface is an important factor in obtaining clear printing, but even nonwoven fabrics with relatively smooth surfaces and densely pressure-finished surfaces have a slight reporous structure when observed microscopically. The binder-free nonwoven fabric has physical properties suitable as a nonwoven fabric for printing, and has an apparent density in the range of 0.2 to 0.4 f/crtl, and is compatible with a wide range of printing techniques and a variety of printing inks. Printing was difficult to obtain.

The present invention improves printability by forming a thin layer of polyvinyl alcohol insolubilized with urethane resin on the surface of a binder-free nonwoven fabric that has suitable physical properties as a nonwoven fabric suitable for printing on clothing labels, table cloths, book covers, etc. The present invention provides a nonwoven fabric that has excellent physical properties and is suitable for printing, which is convenient for the above-mentioned uses.

In general, polyvinyl alcohol has excellent hydrophilicity and good compatibility with other substances, and therefore has excellent affinity with various printing inks.

However, the resin film was relatively hard and did not have sufficient water resistance even after conventional heat treatment or insolubilization treatment such as acetalization.

It is also known to crosslink and insolubilize using melamine as a crosslinking agent, but elution of formalin is unavoidable, and this method cannot be adopted due to the current formalin regulations.

The present invention has discovered that by using an aliphatic urethane resin as a crosslinking agent, a polyvinyl alcohol film that does not elute formalin and has excellent insolubility can be formed.
This makes it possible to use it for clothing labels, book covers, tablecloths, etc.

Methods for forming this insoluble polyvinyl alcohol thin layer include spraying, roll coating, printing, and dipping, but in order to maintain the texture of a clothing label, the thickness must not exceed at least 20 microns. It is desirable that the film be very thin and must be uniformly and appropriately permeated into the nonwoven fabric layer, so spraying, printing, dipping, etc. are suitable.

Embodiments of the present invention will be described in detail below with reference to the drawings.

Example 1 Tetoron 3d x 38gm fibers were impregnated with 26% chloral hydrate, thoroughly dispersed, and then used with a carding machine to obtain a fiber basis weight of 75? /rn' parallel webs,
Heat and pressure treated with a heated roll at 140°C to a thickness of 0.25mm.
, apparent density 0.30? /crtl non-woven fabric, polyvinyl alcohol (trade name Polycizer #17
3 (average degree of polymerization 1700) polymer chemistry)...1
00 parts, aliphatic urethane-terminated isocyanate flock emulsion (trade name Elastron E-37, Daiichi Kogyo Seiyaku)... 10 parts, catalyst... polyvalent metal salt (Elastron Catalyst 32). The nonwoven fabric was impregnated with an appropriate amount of an aqueous solution consisting of 1 part of water and 4900 parts of water so that the solid content was 5%, heated and dried at 110°C, and then heated to 140°C. was heat-treated for 3 minutes.

FIG. 2 shows a cross section of the clothing label according to this example, in which the fibers 1 are activated by chloral hydrate and are bonded at bonding points 4 substantially free of binder, thereby forming a binder-free nonwoven fabric. ing.

Most of the insoluble polyvinyl alcohol applied through secondary processing migrates to the surface layer of the nonwoven fabric due to the migration effect during drying, forming a thin layer 5.

Example 2 Nylon 2d x 51m door fibers were impregnated with 60% of a solvent consisting of 25 parts of butyl paraoxybenzoate and 75 parts of a mixed solvent of 1 part methanol and benzyl alcohol, and the fibers were thoroughly dispersed. Weight 100f/
m" parallel web and heat-press treated with a heated roll at 130°C to a thickness of 0.28 mm and an apparent density of 0.35811/cm.
CRL nonwoven fabric, and as a secondary processing, a polyvinyl alcohol aqueous solution having the same formulation as in Example 1 was applied to one side of the nonwoven fabric by spraying so that the solid content was 3% with respect to the nonwoven fabric. After heating and drying at 110℃, 140℃
Heat treatment was performed at ℃ for 3 minutes.

FIG. 3 shows a cross-section of a clothing label according to this example, in which the fibers 1 are activated with butyl paraoxybenzoate and bonded at bonding points 4 substantially free of binder;
A binder-free nonwoven fabric is formed.

The insoluble polyvinyl alcohol applied by secondary processing forms a thin layer 5 on the surface of the nonwoven fabric.

When the cross sections of the nonwoven fabrics obtained in Example 1.2 were observed under a microscope, it was found that the thickness of each thin layer was 20 microns or less and properly penetrated into the nonwoven fabric layer.

It had a smooth surface, sufficient flexibility, and a soft texture, and when printed, it had clear, glossy, and excellent printability, making it ideal for clothing labels.

Therefore, according to the present invention, (1) Since the fibers are bonded by welding the fibers, the strength is high, and the mechanical strength such as washing resistance and abrasion resistance is excellent.

(2) Since a thin layer of insoluble polyvinyl alcohol is formed on the surface, it has a dense and extremely smooth surface, is compatible with many printing techniques and printing inks, and can provide clear prints.

(3) Due to the excellent oil resistance of polyvinyl alcohol, it is difficult for printing ink to penetrate into the nonwoven fabric layer, resulting in excellent glossy printing properties.

(4) Since the apparent density of the nonwoven fabric is less than 0.49 /crd and the thin layer of polyvinyl alcohol is also extremely thin, it has sufficient flexibility and soft texture.

It has various excellent effects such as.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional printing nonwoven fabric;
FIG. 3 is a cross-sectional view of a nonwoven fabric suitable for printing showing an embodiment of the present invention. 1...Fiber, 2...Binder, 3...
...Printing ink, 4...Welded fiber intersection, 5
...Thin layer of insoluble polyvinyl alcohol.

Claims (1)

[Claims] 1. A nonwoven fabric having an apparent density of 0.2 to 0.1'/i that is bonded substantially without using a binder by the action of a solvent or plasticizer that has a dissolving or swelling effect on the fibers constituting the web. A nonwoven fabric suitable for printing characterized by forming a thin layer of polyvinyl alcohol insolubilized with urethane resin on one surface.