JP2020090742A - Hat brim core material - Google Patents

Abstract

To provide a lightweight hat brim core material having excellent shape retention in MD, TD and any directions, and excellent mechanical strength such as tensile strength and flexural modulus.SOLUTION: There is provided a laminated molded product in which a non-foamed olefin resin layer is laminated on both sides of an olefin resin foam layer with an expansion ratio of 10 times or less and a surface sheet is laminated on both sides of a central material. The surface sheet comprises at least two layers of shape-retaining sheet, and the shape-retaining sheet is a stretched olefin resin sheet, which is bent at 180 degrees in a direction (TD direction) perpendicular to a stretching direction (MD direction), held for 1 minute and then released, with 20 degrees or less of a bending return angle after elapse of 5 minutes, and shape-retaining sheets that are stacked next to each other have different stretching directions.SELECTED DRAWING: Figure 1

Description

The present invention relates to a core material for a brim of a hat, which is made of a polyolefin resin and is lightweight and excellent in mechanical strength and shape retention.

Conventionally, a hat is made of cloth, and its brim is made by laminating and sewing a plurality of cloths.However, the cloth gets wet when raining, absorbs rainwater, and becomes heavy and deforms. Synthetic resin caps and caps made only of synthetic resin are used.

For example, the core material of the Hisashi part is made of a low-foaming PE plate, and the Hisashi part is "formed into a curved surface by heating and pressing and "retained" by rapid cooling. And cap. (For example, refer to Patent Document 1), "Synthetic resin sheets having shape retention in one axial direction are laminated and bonded so that one axial direction of the synthetic resin sheets adjacent to each other forms a predetermined angle. The core material for the brim of the hat." (for example, refer to Patent Document 2) and the like have been proposed.

JP, 2004-218120, A JP, 2006-144198, A

However, since the hispanic part of the cap described in Patent Document 1 is simply hot-pressed and rapidly cooled, the shape-retaining property is small, it is difficult for the user to give a desired shape, and the curved shape However, there is a drawback that the processing cost becomes high because the press processing of 1. is required.

Further, the core material for the brim of the hat described in Patent Document 2 is excellent in shape retention, but has relatively small mechanical strength such as tensile strength and flexural modulus, and the sheet is dense and heavy. There was a drawback.

In view of the above problems, an object of the present invention is to provide a core material for a brim of a hat, which has excellent shape retention in any direction and is lightweight, and which is excellent in mechanical strength such as tensile strength and bending elastic modulus. To do.

That is, the present invention is
[1] A laminated molded article in which a surface sheet is laminated on both sides of a center material in which an unfoamed olefin resin layer is laminated on both sides of an olefin resin foam layer having an expansion ratio of 10 times or less, The sheet is composed of at least two layers of shape-retaining sheet, and the shape-retaining sheet is a stretched olefin resin sheet, which is bent for 180 minutes in a direction (TD direction) perpendicular to the stretching direction (MD direction) and held for 1 minute. The core material for the brim of the hat, which has a bending return angle of 20 degrees or less when 5 minutes have elapsed after the release, and the stretching directions of the shape-retaining sheets that are stacked next to each other are different,
[2] The core material for the brim of the hat according to the above [1], wherein the stretching directions of the shape-retaining sheets that are stacked next to each other are orthogonal to each other.
[3] The olefin resin is a high density polyethylene resin having a weight average molecular weight of 100,000 to 500,000 and a density of 0.945 to 0.965 g/cm ³ , and the above [1] or [2] is described. Core material for brim of hat,
[4] The laminated molded body was bent 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction) of any shape-retaining sheet, held for 1 minute, released, and released for 5 minutes. The core material for the brim of the hat according to any one of the above [1] to [3], wherein the bending return angle at the time is 25 degrees or less.
[5] The core material for the brim of the hat according to any one of the above [1] to [4], which has a specific gravity of 0.83 to 0.92, and
[6] The tensile strength is 100 to 200 MPa, and the bending elastic modulus in the direction perpendicular to the stretching direction (MD direction) of any shape-retaining sheet (TD direction) is 3500 to 4500 MPa. The present invention relates to a brim core material for a hat according to any one of [1] to [5].

The structure of the core material for the brim of the hat of the present invention is as described above, is a laminated molded product made of an olefin resin, has excellent shape retention in any direction, is lightweight, and has tensile strength and bending. Excellent mechanical strength such as elastic modulus.

It is sectional drawing which shows an example of the core material for collars of the hat of this invention. (A) is a plan view showing an example of the shape-retaining sheet in the present invention, and (B) and (C) are side views showing a method for measuring a 180-degree bending return angle (TD-direction bending).

The core material for the brim of the hat of the present invention is a laminate in which a non-foamed olefin resin layer is laminated on both sides of an olefin resin foam layer having an expansion ratio of 10 times or less, and a surface sheet is laminated on both sides of a center material. A molded product, wherein the surface sheet is composed of at least two layers of a shape-retaining sheet, and the shape-retaining sheet is a stretched olefin resin sheet, and is 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction). The bent back angle is 20 degrees or less when 5 minutes have passed after being released, and the shape-retaining sheets laminated next to each other have different stretching directions. To do.

Next, description will be given with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a brim core material for a hat of the present invention. In the figure, 1 is a center material, and 2 and 2 are surface sheets laminated on both sides of the center material 1. In the core material 1, unfoamed olefin resin layers 12 and 12 are laminated on both surfaces of an olefin resin foam layer 11 having a foaming ratio of 10 times or less. The topsheet 2 is composed of a first shape-retaining sheet 21 and a second shape-retaining sheet 22, and the first shape-retaining sheet 21 and the second shape-retaining sheet 22 are laminated so as to have different stretching directions. The first shape-retaining sheet 21 and the second shape-retaining sheet 22 are stretched olefin resin sheets, which are bent 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction) and held for 1 minute. It has shape retention with the post-release and the bending return angle of 20 minutes or less after 5 minutes from the release.

As the polyolefin-based resin, any olefin-based resin having film forming ability can be used. For example, high-density polyethylene resin, medium-density polyethylene resin, low-density polyethylene resin, linear low-density polyethylene resin, polypropylene resin, ethylene- Propylene copolymer, ethylene-butene-1 copolymer, ethylene-pentene-1 copolymer, ethylene-hexene-1 copolymer, ethylene-octene-1 copolymer, ethylene-vinyl acetate copolymer, ethylene -(Meth)acrylic acid ester copolymer, ethylene-vinyl chloride copolymer, ethylene-propylene-butene copolymer and the like can be mentioned.

Regarding the weight average molecular weight of the polyolefin resin, when the weight average molecular weight is less than 100,000, mechanical strength or creep resistance is lowered, and when it exceeds 500,000, the melt viscosity becomes high, and Melt moldability is lowered and it is difficult to obtain a uniform sheet, so 100,000 to 500,000 is preferable. In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography (GPC).

The melt index (hereinafter, MI) of the polyolefin resin is preferably 0.1 to 20 (g/10 minutes), which is excellent in film formability, and more preferably 0.2 to 10 (g/10 minutes). Is. Incidentally, MI is an index representing the melt viscosity of the thermoplastic resin specified in JIS K 7210.

Among the above polyolefin-based resins, a high-density polyethylene resin having a high mechanical strength and a density of 0.945 to 0.965 g/cm ³ is preferable. The high-density polyethylene resin is a polyethylene resin polymerized by the medium-low pressure method and having a density of 0.945 to 0.965 g/cm ³ , and a trace amount of propylene, butene-1, pentene-1, hexene-1, octene-1. .Alpha.-olefins such as may be copolymerized.

Further, the polyolefin-based resin constituting each layer may be different, but if the same type of polyolefin-based resin, the adhesion of each layer is excellent, and the mechanical strength of the obtained brim core material for the hat is improved, It is preferably composed of the same type of polyolefin resin.

In the polyolefin resin, if necessary, a heat stabilizer, a heat resistance improver, a light stabilizer, an ultraviolet absorber, an antioxidant, an antistatic agent, an impact modifier, an antifogging agent, a flame retardant, a colorant, etc. It may be added.

The foaming ratio of the olefin resin foamed layer 11 of the central material 1 is 10 times or less, preferably 6 times or less, and more preferably 6 times or less, because the weight cannot be reduced when it is lowered and the mechanical strength is lowered when it is increased. Is 1.5 to 3 times.

The unfoamed olefin resin layer 12 of the center material 1 is a layer that is laminated on the olefin resin foam layer 11 to impart mechanical strength to the center material 1, and is laminated on both sides of the olefin resin foam layer 11. It is preferable that they are firmly bonded.

The specific gravity and thickness of the core material 1 may be appropriately determined depending on the application and required physical properties, but generally, the specific gravity is 0.65 to 0.85 and the thickness is 0.2 to 5 mm, preferably 0. 4 to 1 mm. Further, it is preferable that the unfoamed olefin resin layers 12, 12 laminated on both sides have substantially the same thickness so that the mechanical strength is not unevenly distributed. Unfoamed olefin resin layer 12: olefin resin foam The thickness ratio of layer 11: unfoamed olefin resin layer 12 is preferably 1:1 to 3:1 and more preferably 1:1.5 to 2.5:1.

The shape-retaining sheet is a stretched olefin-based resin sheet having shape-retaining property, and the shape-retaining property is obtained by bending 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction) and holding for 1 minute. The bending return angle (hereinafter, “180° bending return angle”) when released and 5 minutes after the release is 20° or less. The shape retention is a property of retaining the deformed shape as it is. Therefore, the smaller the bending return angle is, the better the shape retention is. The 180 degree bending return angle is 20 degrees or less and 15 degrees or less. Is preferable, and more preferably 12 degrees or less.

Next, a method of measuring the “180 degree bending return angle” will be described with reference to the drawings. FIG. 2A is a plan view showing an example of the shape-retaining sheet of the present invention, and FIGS. 2B and 2C are side views showing a method of measuring the “180 degree bending return angle”. Reference numeral 23 in the figure is a shape-retaining sheet, which is stretched in the direction of arrow X. That is, the X direction is the stretching direction and the MD direction. The arrow Y direction is a direction perpendicular to the stretching direction (MD direction) (TD direction).

The "180 degree bending return angle" is measured by first measuring the flat shape-retaining sheet 23 shown in FIG. 2A along the dotted line 24, that is, in the direction (TD direction) perpendicular to the stretching direction (MD direction). Two folds are made, and as shown in FIG. 2(B), two layers are superposed (folded at 180 degrees). When the shapes are overlapped and held for one minute and then released, as shown in FIG. 2(C), the overlapped shape holding sheets 23 act so as to return to their original shapes. When the time has elapsed, the angle θ formed by the two layers (the angle at which the molded body bent by 180 degrees returns to its original shape) is measured. This angle θ is the “180 degree bending return angle”.

In addition, after bending for 90 minutes in a direction (TD direction) at right angles to the stretching direction (MD direction), holding for 1 minute, and releasing, a bending return angle (hereinafter, referred to as “90 degree bending return”) after 5 minutes have elapsed. The angle ") is preferably 20 degrees or less, more preferably 15 degrees or less, and further preferably 12 degrees or less.

The method of measuring the “90 degree return angle” is the same as the “method of measuring the 180 degree return angle” except that the bending angle is 90 degrees. That is, the measuring method of “90 degree bending return angle (TD direction bending)” is to bend a flat shape-retaining material at 90 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction), and measure the shape as 1 Since the shape-retaining sheet acts to return to the original shape when released after being held for a minute, the angle formed by the folded shape-retaining sheet is measured 5 minutes after the release. The angle obtained by subtracting 90 degrees from the measured angle (the angle at which the shape retaining sheet bent to 90 degrees returns to the original shape) is the "90 degree bending return angle".

The mechanical strength of the shape-retaining sheet is preferably high, the tensile elastic modulus in the stretching direction (MD direction) is preferably 10 to 30 GPa, and the tensile strength is preferably 300 to 700 MPa. In the present invention, the tensile elastic modulus and tensile strength are values measured according to JIS K 7127.

The thickness of the shape-retaining sheet is not particularly limited, but it becomes heavier as it becomes thicker, and it becomes difficult to manufacture a sheet having shape-retaining property, and therefore it is generally 0.1 to 1 mm.

Furthermore, in order to impart flexibility, suppleness, etc. to the shape-retaining sheet made of a high-density polyethylene resin and prevent vertical tearing, an α-olefin copolymer, a linear low-density polyethylene, is added to the high-density polyethylene resin, One or more resins selected from the group consisting of olefin-based thermoplastic elastomers and metallocene-based polypropylene resins may be added, but if the addition amount increases, the bending reversion angle increases and the shape retention decreases, so It is preferably 7 parts by weight or less with respect to 100 parts by weight of the density polyethylene resin.

The topsheet 2 is formed of at least two shape-holding sheets, and the shape-holding sheets that are laminated next to each other have different stretching directions. It is preferable that the shape-retaining sheet is uniformly arranged in the stretching direction so that the mechanical strength of the surface sheet is not unevenly distributed.

That is, for example, when the surface sheet is composed of two layers of the first shape-retaining sheet and the second shape-retaining sheet, the first shape-retaining sheet and the second shape-retaining sheet are arranged so that the stretching directions thereof are orthogonal to each other. Is preferred. Further, when the surface sheet is composed of three layers of the first shape-holding sheet, the second shape-holding sheet and the third shape-holding sheet, the stretching directions of the shape-holding sheets are arranged so as to differ by 60 degrees. Is preferred. Further, when the surface sheet is composed of four layers of the first shape-holding sheet, the second shape-holding sheet, the third shape-holding sheet, and the fourth shape-holding sheet, the stretching directions of the adjacent shape-holding sheets are orthogonal to each other. Or, it is preferable that they are arranged so as to differ by 45 degrees.

Further, the topsheet 2 may be composed of at least two shape-holding sheets, but it is not practical to stack a large number of shape-holding sheets, and generally, two to four shape-holding sheets are stacked. preferable.

The thickness of the topsheet 2 is not particularly limited, but it becomes heavier as it becomes thicker, and it becomes necessary to stack a large number of shape-retaining sheets, which makes manufacturing difficult. Therefore, it is generally 0.2 to 2 mm. ..

The structure of the core material for the brim of the hat of the present invention is a laminated molded body as described above, and it is preferable that it is lightweight and excellent in mechanical strength and shape retention, and the specific gravity is preferably 0.83 to 0.92. , More preferably 0.85 to 0.92, the tensile strength is 100 to 200 MPa, and a direction perpendicular to the stretching direction (MD direction) of any shape-retaining sheet constituting the laminated molded body (TD direction). It is preferable that the flexural modulus of elasticity is 3500 to 4500 MPa. The flexural modulus is a value measured at a test speed of 5 mm/min according to JIS K7171.

Further, the shape retention of the brim core material (laminated body) of the hat is preferably substantially the same in any direction, and the 180-degree bending return angle and the 90-degree bending return angle are preferably 30 degrees or less. A degree of less than or equal to is more preferable. In particular, the brim material for the brim of the hat (laminated molded body) is bent 180 degrees in the direction (TD direction) perpendicular to the stretching direction (MD direction) of any shape-holding sheet, held for 1 minute, and then released. The bending return angle after 5 minutes from the release is preferably 25 degrees or less.

The thickness of the brim core material for the hat is not particularly limited and may be appropriately determined depending on the intended use, but is generally 0.5 to 20 mm, preferably 1 to 10 mm.

The manufacturing method of the core material is not particularly limited, and any conventionally known manufacturing method may be adopted. For example, an olefin resin foam sheet having an expansion ratio of 10 times or less and an unfoamed olefin resin sheet are manufactured in advance, and the unfoamed olefin resin sheet is laminated on both surfaces of the olefin resin foam sheet to form an adhesive or The adhesive may be applied by heat fusion. However, since it is preferable that the olefin resin foam layer and the unfoamed olefin resin layer are bonded uniformly and firmly, the olefin resin foam layer is preferably manufactured by the three-layer extrusion method.

The three-layer extrusion method is a conventionally known method for producing a laminated sheet, in which two resin compositions are simultaneously extruded into sheets from different extruders and laminated to produce a three-layer sheet. An extrusion method using a die, a feed block and the like can be mentioned. In the production of the above core material, an olefin resin and a foamable olefin resin composition are simultaneously extruded, and the foamable olefin resin composition is foamed to obtain an olefin resin foam sheet, and at the same time, both surfaces of the olefin resin foam sheet are obtained. A non-foamed olefin resin sheet obtained by extrusion-molding an olefin resin is laminated in a molten state in a multi coat die, a feed block or the like to produce a three-layer sheet.

The foaming method is not particularly limited, and examples thereof include a chemical foaming method and a gas foaming method. As the expandable olefin resin composition used for foaming, any conventionally known expandable olefin resin composition can be used, and it comprises an olefin resin and a foaming agent. Examples of the foaming agent include a thermal decomposition type chemical foaming agent, carbon dioxide gas, nitrogen gas and the like.

Examples of the thermal decomposition type chemical foaming agent include sodium bicarbonate, ammonium bicarbonate, sodium borohydride, azodicarbamide, N,N-dinitrosopentamethylenetetramine, P,P-oxybis(benzenesulfonylhydrazide). , Azobisisobutyronitrile, paratoluenesulfonyl hydrazide and the like.

The shape-retaining sheet is made of a stretched olefin resin sheet, but the method for producing the olefin resin sheet is not particularly limited, and any conventionally known production method may be adopted, for example, extrusion method, inflation method, casting method. Method, T-die method, calendar method and the like.

The shape-retaining sheet is a sheet obtained by stretching an olefin resin sheet, and the stretching method may be any conventionally known stretching method, and examples thereof include rolling, and a method in which rolling and uniaxial stretching are used in combination.

First, a method for manufacturing a shape-retaining sheet by rolling will be described. Rolling is a method in which the olefin resin sheet is supplied to a pair of rolling rolls, crushed and stretched.

The thickness of the olefin-based resin sheet before rolling is not particularly limited, but if it is too thick, a large pressing force or a pulling force is required to crush the olefin-based resin sheet with the rolling roll, which causes bending of the rolling roll, etc. Due to this, uniform rolling in the width direction may be difficult. Conversely, if it is too thin, the thickness of the olefin-based resin sheet after rolling becomes too thin, making it difficult to perform uniform rolling. May contact with each other to shorten the life of the rolling roll, so 0.2 to 15.0 mm is preferable.

Since the rolling temperature cannot be uniformly rolled when the rolling temperature is low, and melt cutting is performed when the rolling temperature is high, the roll temperature during rolling is preferably in the range of "melting point-40°C" to the melting point of the olefin resin of the olefin resin sheet to be rolled. , And more preferably, "melting point-30°C" to "melting point-5°C" of the olefin resin. In the present invention, the melting point refers to the maximum point of the endothermic peak associated with the melting of crystals, which is observed when thermal analysis is performed by a differential scanning calorimeter (DSC).

If the pressing force (linear pressure) applied to the olefin resin sheet by the rolling roll is too small, it may not be possible to obtain a predetermined rolling ratio, and if it is too large, not only will the bending of the rolling roll occur, Since slippage is likely to occur between the rolling roll and the olefin resin sheet, and uniform rolling may be difficult, the applied pressure is preferably 100 MPa to 3000 MPa, more preferably 300 MPa to 1000 MPa.

When the rolling ratio is less than 5 times, sufficient shape retention cannot be imparted, so that the rolling ratio is preferably 5 times or more, more preferably 7 times or more, and further preferably 9 times or more. Although there is no upper limit of the rolling ratio, the higher the rolling ratio is, the more load is applied to the rolling equipment. The rolling ratio is defined by (the cross-sectional area of the sheet before rolling)/(the cross-sectional area of the sheet after rolling), but since the width of the sheet hardly changes before and after rolling, (the thickness of the sheet before rolling is )/(Thickness of sheet after rolling).

Next, a method for manufacturing the shape-retaining sheet by using both rolling and uniaxial stretching will be described. In the method for producing the shape-retaining sheet, it is preferable that the olefin resin sheet is rolled and then uniaxially stretched at a total stretching ratio of 10 to 40, and the rolling method is as described above.

When the rolling ratio is less than 5 times, the effect of suppressing necking during uniaxial stretching which will be performed later cannot be obtained, high-magnification uniaxial stretching cannot be performed, or the uniaxial stretching step is performed. Therefore, it is preferably 5 times or more, more preferably 7 times or more. Although there is no upper limit of the rolling ratio, the higher the rolling ratio is, the more load is applied to the rolling equipment.

As the uniaxial stretching method, any conventionally known method may be adopted, and examples thereof include a uniaxial stretching method such as a roll uniaxial stretching method and a zone uniaxial stretching method while stretching with heating with a heater or hot air. In the case of highly stretching, a method of multistage uniaxial stretching in which uniaxial stretching is repeated a plurality of times is preferable. When performing multi-stage uniaxial stretching, the number of times of stretching is preferably 2 to 20 times, more preferably 3 to 15 times, and further preferably 4 to 10 times.

When performing multi-stage stretching by the roll uniaxial stretching method, it is desirable to install a feeding pinch roll, a take-up pinch roll, and at least one, preferably a plurality of contact rolls rotating at a constant speed between these rolls. By installing such a contact roll, uniform stretchability can be improved and stable stretch molding can be performed.

The contact roll performs uniaxial stretching by applying frictional force to the olefin resin sheet without being pinched. The contact roll may be connected to the payout roll and/or the take-up roll by a connecting member made of a gear, a chain, a pulley, a belt, or a combination thereof.

The uniaxial stretching temperature cannot be uniformly stretched when the temperature is low, and the olefin resin sheet is melt-cut when the temperature is high, so that the range of "melting point-60°C" to the melting point of the olefin resin of the olefin resin sheet to be stretched is more preferable. The melting point of the olefin resin is preferably -50°C to -5°C.

Since the total draw ratio of the uniaxial draw ratio is preferably 10 to 40, it may be determined so that the total draw ratio falls within this range in consideration of the rolling draw ratio, but if the uniaxial draw ratio is small, the mechanical strength is reduced. Is 1.1 times or more, and more preferably 1.3 times or more. The upper limit is not particularly limited, but is preferably 4 times or less, more preferably 3.0 times or less. The total stretching ratio is a value obtained by multiplying the rolling ratio and the uniaxial stretching ratio.

In order to improve the dimensional stability of the shape-retaining sheet obtained by the above manufacturing method, the shape-retaining sheet may be annealed at a temperature of "melting point-60°C" to melting point of the olefin resin. When the annealing temperature is low, the dimensional stability does not improve, and when it is used for a long time, warpage occurs, and when it is high, the olefin resin dissolves and the orientation disappears, and the tensile elastic modulus and tensile strength decrease. It is preferable to anneal at a temperature of "melting point-60°C" to melting point of the resin.

Annealing means performing heat treatment in the production line.When annealing, the shape-retaining sheet will be stretched if a large tension is applied, and if it is not tensioned or contracts in a very small state, It is preferable to carry out in a state where the length of the holding sheet in the stretching direction does not substantially change, and it is preferable that no pressure is applied to the shape holding sheet. That is, it is preferable to anneal the shape-retaining sheet so that the length of the annealed shape-retaining sheet becomes 1.0 or less of the length of the shape-retaining sheet before annealing.

Therefore, when the shape-retaining sheet is continuously annealed while moving in the heating chamber with a roll such as a pinch roll, the feed rate ratio of the shape-retaining sheet on the inlet side and the outlet side is set to 1.0 or less. Preferably by annealing.

The heating method for annealing is not particularly limited, and examples thereof include a method of heating with hot air, a heater, a heating plate, hot water, or the like. The annealing time is not particularly limited, and varies depending on the thickness and thickness of the stretched shape-retaining material and the annealing temperature, but is generally preferably 10 seconds or longer, more preferably 30 seconds to 60 minutes, and further preferably 1 ~ 20 minutes.

The annealed shape retention sheet may be further aged in the temperature range of 40° C. to the melting point of the olefin resin. By aging, the dimensional stability of the shape-retaining sheet annealed becomes more excellent.

Aging does not mean continuous processing in the production line, but means heat-treating sheet-shaped products, scrolls, etc. that have once been processed into a shape-retaining sheet by letting them sit for a relatively long time (minutes or hours). means. When the aging temperature becomes lower, it becomes the same as when it is left at room temperature, and when it becomes higher, it is thermally deformed, so that it is in the temperature range of 40°C to the melting point of the olefin resin. However, the effect does not increase, so 12 hours to 7 days is preferable.

The method for producing the topsheet by laminating the plurality of shape-retaining sheets and the method for laminating the topsheet on both surfaces of the center material may be any conventionally known method, for example, an adhesive or a pressure-sensitive adhesive. And a method of adhering the sheet.

Further, it is preferable that the core material (laminated molded body) for the brim of the hat of the present invention has high mechanical strength and is not unevenly distributed. Therefore, a plurality of shape-retaining sheets or a surface sheet and a center material are evenly and firmly adhered and bonded. Preferably. Therefore, it is preferable that the hot-melt type olefin resin sheet is laminated between a plurality of shape-retaining sheets or between the surface sheet and the center material, and is bonded by heating and pressing.

The hot-melt olefin-based resin sheet is a shape-retaining sheet and an olefin-based resin that constitutes the center material so that the shape-retaining property of the shape-retaining sheet may be deteriorated or the center material may not be deformed when laminated by heating and pressing. It is preferably made of an olefin resin having a melting point lower than the melting point, and examples thereof include linear low-density polyethylene resin and ethylene-vinyl acetate copolymer.

Therefore, the olefin resin constituting the shape-retaining sheet and the center material is a high-density polyethylene resin having a weight average molecular weight of 100,000 to 500,000 and a density of 0.945 to 0.965 g/cm ³ , and a hot melt olefin resin sheet. It is preferable that the olefin-based resin constituting is a linear low-density polyethylene resin.

Further, a hot-melt type olefin resin sheet may be adhered to the surface of the shape-retaining sheet or the surface sheet in advance. For this adhesion, any conventionally known method may be adopted, for example,
A method for extrusion-coating a hot-melt olefin resin in a molten state on the surface of a shape-holding sheet or a surface sheet, laminating a hot-melt olefin resin sheet on the surface of a shape-holding sheet or a surface sheet, and a hot-melt olefin resin Examples include a method of heating and pressing the sheet to bond it.

At the time of the above-mentioned adhesion, if a plurality of narrow shape-retaining sheets are aligned in the stretching direction so that the stretching directions are the same and are bonded to the hot-melt olefin resin sheet, a wide laminated molded body can be easily formed. Can be manufactured.

When manufacturing a core material for a collar of a hat by heating and pressing the surface sheet and the center material (laminated molded body), the surface sheet and the center material on which the hot-melt olefin resin sheet is laminated are used, and further, A hot-melt type olefin resin sheet may be laminated between the surface sheet and the center material and heated and pressed.

Since the method for producing the core material and the shape-retaining sheet in the present invention is as described above, the method for producing the brim core material for a hat (laminated molded article) of the present invention is an olefin resin, an olefin resin and a foaming agent. A step of extruding a resin composition consisting of a three-layer extruder to obtain a core material in which an unexpanded olefin resin layer is laminated on both surfaces of an olefin resin foam layer having an expansion ratio of 10 times or less; After rolling, uniaxially stretched to a total stretching ratio of 10 to 40 times, bent 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction), held for 1 minute, released, and then released for 5 minutes. A step of obtaining a shape-retaining sheet having a bending return angle of 20 degrees or less when the time has elapsed, and laminating at least two layers of the shape-retaining sheet obtained on both surfaces of the obtained center material so that the stretching directions are different from each other. A manufacturing method including a step of adhering by heating and pressing is preferable.

The brim of the hat is formed by coating the brim material for the brim of the hat with a coating material. Further, the hat is formed by installing the brim of the hat on the hat body.

As the above covering material, any conventionally known covering material that is used when manufacturing a hat can be used, and examples thereof include cloth, an olefin resin sheet, a vinyl chloride resin sheet, and a nonwoven fabric.

As a method of coating the brim core material of the hat with the coating material, any conventionally known method may be adopted. For example, the brim core material of the hat is coated with the coating material, and a rubber-based, acrylic-based, or urethane-based material is used. System, a method of adhesively adhering with a silicone-based adhesive, a method of adhering with a hot-melt adhesive such as ethylene-vinyl acetate copolymer, a linear low-density polyethylene resin, a method of sewing, etc. Be done.

As the hat body, any conventionally known hat body used when manufacturing a hat can be used, and for example, it is produced from cloth, olefin resin sheet, vinyl chloride resin sheet, non-woven fabric, straw or the like. A hat.

As a method of installing the brim of the hat on the hat body, any conventionally known method may be adopted, for example, by installing the brim of the hat on the hat body, rubber type, acrylic type, urethane type, silicone type, etc. Examples thereof include a method of sticking and sticking with a sticky adhesive, a method of sticking with a hot-melt type adhesive such as an ethylene-vinyl acetate copolymer, a linear low-density polyethylene resin, and a sewing method.

Next, examples of the present invention will be described, but the present invention is not limited to the examples.

(Example 1)
A low-density polyethylene resin (“Suntech LD” manufactured by Asahi Kasei) is supplied to two surface layer forming extruders of a three-layer co-extruder (manufactured by Hitachi Zosen), and a high-density polyethylene resin is supplied to the intermediate layer forming extruder. (Novatec HD manufactured by Nippon Polyethylene Co., Ltd., weight average molecular weight 330,000, MFR 0.40 g/10 minutes, density 0.956 g/cm ³ , melting point 133° C.) 100 parts by weight and 0.25 parts by weight of azodicarbonamide. Functional resin composition was supplied, melted and kneaded at a cylinder temperature of 180 to 230° C., and coextruded in three layers to obtain a center material having a thickness of 1.0 mm.

The obtained center material has an unfoamed low-density polyethylene resin layer laminated on both sides of a high-density polyethylene resin foam layer. Low-density polyethylene resin layer: high-density polyethylene resin foam layer: low-density polyethylene resin layer thickness The ratio was approximately 1:2:1. The high-density polyethylene resin foam layer had a foaming ratio of about 2 times and a specific gravity of 0.7.

High-density polyethylene resin ("Novatech HD" manufactured by Nippon Polyethylene Co., Ltd., weight average molecular weight 330,000, MFR 0.40 g/10 minutes, density 0.956 g/cm ³ , melting point 133° C.) was fed in the same direction with a twin-screw kneading extruder (plastic). (Made by Kogaku Kenkyusho Co., Ltd.) and melt-kneaded at a resin temperature of 200° C., and the melt-kneaded product was formed into a sheet by a calender forming machine controlled at a roll temperature of 110° C. to obtain a sheet having a thickness of 2.8 mm.

The obtained sheet was rolled 10 times by using a roll forming machine (manufactured by Sekisui Machinery Co., Ltd.) heated to 125° C., and then a hot air heating type multi-stage stretching device (manufactured by Kyowa Engineering) heated to 110° C. As a result, uniaxial multi-stage stretching was performed 1.4 times to obtain a stretched sheet having a total stretching ratio of 14 times and a thickness of 0.20 mm.

The stretched sheet obtained was supplied at a inlet speed of 2.75 m/min to a hot air heating tank having a line length of 19.25 m, which was set at 125° C. with a pinch roll, and was set at an outlet speed of 2.75 m/min. Then, primary annealing is performed for 7 minutes, and then secondary annealing is similarly performed to obtain an annealed stretched sheet, which is then supplied to a constant temperature bath at 60° C. and aged for 24 hours to obtain a shape-retaining sheet. Obtained.

The obtained shape-retaining sheet was cut into a width of 10 mm and a length of 15 cm, supplied to a Tensilon universal testing machine ("RTC-1250A type" manufactured by Orientec Co., Ltd.), and stretched in the MD direction according to JIS K 7127. A tensile test was conducted at a speed of 100 mm/min to measure the tensile elastic modulus, tensile strength and elongation at break. The tensile modulus was 24 GPa, the tensile strength was 500 MPa, and the elongation at break was 5%.

The obtained shape-retaining sheet was cut into a width of 10 mm and a length of 15 cm, and the 180-degree bending return angle and the 90-degree bending return angle were measured and found to be 7 degrees and 5 degrees.

A linear low-density polyethylene resin ("Novatech LL" manufactured by Nippon Polyethylene Co., Ltd., MFR 2.1 g/10 min, density 0.920 g/cm ³ , melting point 123°C) was applied in the same direction by a twin-screw kneading extruder (Plastics Engineering Laboratory). ) And melt-kneaded at a resin temperature of 200° C., and the melt-kneaded product was formed into a sheet by a calender molding machine controlled at a roll temperature of 110° C. to obtain a hot-melt adhesive sheet having a thickness of 0.03 mm.

The obtained hot-melt adhesive sheet is laminated on one surface of the obtained shape-retaining sheet, and the hot-melt adhesive sheet having a thickness of 0.23 mm is adhered by pressure bonding from the hot-melt adhesive sheet side at a temperature of 125° C. and a pressure of 50 KPa. The obtained multilayer shape holding sheet was obtained.

First multi-layer shape retaining sheet/hot melt adhesive sheet/Second multi-layer shape retaining sheet/hot melt adhesive sheet/Center material/Hot melt adhesive sheet/Third multi-layer shape retaining sheet/Hot melt adhesive sheet/ The fourth multi-layer shape holding sheet was laminated in this order to obtain a laminated sheet. The hot-melt adhesive sheets in the first to fourth multilayer shape-holding sheets are positioned on the center material side, and the stretching directions of the first multilayer shape-holding sheet and the fourth multilayer shape-holding sheet are The second multi-layer shape holding sheet and the third multi-layer shape holding sheet were the same, and the stretching directions were arranged so as to be orthogonal to the stretching directions of the first and fourth multi-layer shape holding sheets.

Next, the obtained laminated sheet was supplied to a press machine and heated and pressed at a temperature of 125° C. and a pressure of 30 MPa to bond the laminated sheet to obtain a brim material for the collar of the hat (laminated molded body) of the present invention. The thickness of the obtained brim core material for the hat was 1.92 mm, and the specific gravity was 0.85.

The obtained brim material for the brim of the hat is cut into a width of 0 mm and a length of 15 cm, supplied to a Tensilon universal testing machine ("RTC-1250A type" manufactured by Orientec Co., Ltd.), and stretched in accordance with JIS K 7127. A tensile test was performed in the MD direction) at a speed of 100 mm/mm to measure the tensile elastic modulus, tensile strength, and elongation at break. The tensile elastic modulus was 3 GPa, the tensile strength was 120 MPa, and the elongation at break was 9%. The flexural modulus measured according to K 7171 at a test speed of 5 mm/min was 4000 MPa.

The obtained brim material for the brim of the hat was cut into a width of 10 mm and a length of 15 cm along the stretching direction of the shape-retaining sheet, and the 180-degree bending return angle and the 90-degree bending return angle were measured to be 20 degrees and 30 degrees. Met. Further, the laminated molded body was cut into a width of 10 mm and a length of 15 cm at an angle of 45 degrees with respect to the stretching direction of the shape-retaining sheet, and a 180-degree bending return angle and a 90-degree bending return angle were measured. It was degree.

The obtained brim material for the brim of the hat was supplied to a punching machine equipped with a Thomson blade, punched into a brim shape of the hat, and cloth was laminated on both sides of the blank and sewn to obtain a brim of the hat. Next, the brim of the hat was sewn to the body of the hat to obtain the hat. When the brim of the obtained hat was bent by hand by about 30 degrees and about 45 degrees in any direction, the brim was easily bent and each shape could be retained.

The brim core material for a hat of the present invention has excellent mechanical strength such as tensile strength and flexural modulus, has little directionality in shape retention, and has excellent shape retention in any direction. The brim of the hat manufactured using the brim core material has excellent mechanical strength such as tensile strength and flexural modulus, has little directionality in shape retention, and has excellent shape retention in any direction. Can be preferably used.

DESCRIPTION OF SYMBOLS 1 Core material 11 Olefin-based resin foam layer 12 Unfoamed olefin-based resin layer 2 Surface sheets 21, 22, 23 Shape retention sheet X MD direction (stretching direction)
Y TD direction (direction perpendicular to stretching direction)
θ 180 degree bending return angle

Claims (6)

A laminated molded article, in which a surface sheet is laminated on both surfaces of a central material, in which an unfoamed olefin resin layer is laminated on both surfaces of an olefin resin foam layer having an expansion ratio of 10 times or less, wherein the surface sheet is at least A two-layer shape-retaining sheet, which is a stretched olefin resin sheet, is bent 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction), held for 1 minute, and then released. However, the core material for the brim of the hat is characterized in that the bending return angle after 5 minutes has elapsed from the release is 20 degrees or less, and the stretching directions of the shape-retaining sheets laminated adjacent to each other are different. The core material for a brim of a hat according to claim 1, wherein the shape-maintaining sheets that are stacked next to each other have their stretching directions orthogonal to each other. The core material for a brim of a hat according to claim 1 or 2, wherein the olefin resin is a high-density polyethylene resin having a weight average molecular weight of 100,000 to 500,000 and a density of 0.945 to 0.965 g/cm ^3. .. The laminated molded body is bent 180 degrees in a direction (TD direction) perpendicular to the stretching direction (MD direction) of any shape-retaining sheet, held for 1 minute, released, and then bent 5 minutes after the release. The core material for a brim of a hat according to any one of claims 1 to 3, wherein the return angle is 25 degrees or less. The core material for a brim of a hat according to any one of claims 1 to 4, wherein the specific gravity is 0.83 to 0.92. The tensile strength is 100 to 200 MPa, and the bending elastic modulus in a direction (TD direction) perpendicular to the stretching direction (MD direction) of any one of the shape retaining sheets is 3500 to 4500 MPa. The core material for the brim of the hat according to any one of 5 above.