EP3508090B1

EP3508090B1 - Slider for slide fastener

Info

Publication number: EP3508090B1
Application number: EP16915198.2A
Authority: EP
Inventors: Takuya Koizumi; Kazuto SIODA; Shuhei TAGAYA; Yasuharu Yoshimura; Hideki UEDA
Original assignee: YKK Corp
Current assignee: YKK Corp
Priority date: 2016-09-02
Filing date: 2016-09-02
Publication date: 2024-01-10
Anticipated expiration: 2036-09-02
Also published as: TW201811217A; WO2018042641A1; EP3508090A4; EP3508090A1; TWI620524B

Description

TECHNICAL FIELD

The present invention relates to a slide fastener, and more specifically to a slider for a slide fastener.

BACKGROUND ART

Slide fasteners are widely used not only for daily necessities such as clothing items, bags, shoes and miscellaneous goods, but also for industrial goods such as water storage tanks, fishing nets and space suits, as opening and closing tools for articles.
In general, the slide fastener is mainly composed of three parts: a pair of elongated fastener tapes; an element row which is an engaging portion of fasteners and is attached along one side edge of each tape; and a slider for controlling opening and closing of the fastener by engaging and disengaging a pair of element rows. The slider has a function of engaging or disengaging the element rows by sliding while inserting the element rows into the slider. A pull tab is generally attached to an outer surface of the slider, and a user can control the opening and closing of the slide fastener by pulling the pull tab in the sliding direction of the slider.
Parts for the slide fastener are often produced using metal as a material, and the metal material practically used for the slider is a zinc alloy. In a conventional method for producing a typical zinc alloy slider, a slider body and a pull tab attaching post each having a predetermined shape are integrally formed by a die casting method using a zinc alloy, and the pull tab attaching post is then inserted into a attachment hole formed at one end of a pull tab, and the pull tab attaching post is then subjected to a caulking process (bending process) so that the pull tab is movably attached to the slider body.
Materials that may be used for a metal slider include, in addition to the zinc alloy, aluminum alloys. Since the aluminum alloy has lightweight, the use of the aluminum alloy as a metal base material for the fastener parts can allow reduction of a weight of the metal slide fastener. International Publication WO 2011/077567 A1 describes a slider for a slide fastener, the slider comprising a slider body and a pull tab attaching post formed on the slider body, the slider comprising an aluminum alloy as a base material for a slider. Particularly, WO 2011/077567 A1 discloses aluminum-magnesium-based alloys and aluminum-copper-silicon-based alloys as aluminum alloys.
JP 2004 256880 A discloses aluminum alloy diecast molding in which permanent growth can be suppressed even without performing heat treatment for stabilization. The aluminum alloy, disclosed for use in engine cylinder blocks, has a lead percentage of 0.05% by mass or less. The publication to Taylor J A, "Metal-related castability effects in aluminium foundry alloys", CAST METALS, F & M SCIENTIFIC AND TECHNICAL PUBLICATION, REDHILL, GB, discloses in Table 1 a composition of a primary aluminium alloy having about 99.5% to 99.85%of aluminium, with Si (200 to 1000 ppm) and Cu (5 to 100 ppm).

SUMMARY OF INVENTION

Technical Problem

Aluminum alloy members cast by the die casting method are widely used for engine parts and transmission parts for motor vehicles, because the members have characteristics such as high dimensional accuracy, high productivity and high degree of freedom of shape. However, the die casting of the aluminum alloy causes a problem that cracking easily occurs when plastic working such as caulking or bending process is applied to a pull tab attaching post of a small part such as a slider, which is difficult to put into practical use. On the other hand, the slider also requires strength sufficient to withstand stress applied when a user manipulates the pull tab.
Therefore, an object of the present invention is to provide an aluminum alloy slider for a slide fastener, which has both practical strength and plastic workability.

Solution to Problem

According to the aluminum-copper-silicon-based alloy disclosed in WO 2011/077567 A1 , ADC 12 defined in JIS H 5302: 2006 is considered to be used as a die casting alloy. The standard defines that the ADC 12 contains from 1.5 to 3.5% by mass of Cu, from 9.6 to 12.0% by mass of Si, 0.3% by mass or less of Mg, 1.0% by mass or less of Zn, 1.3% by mass or less of Fe, 0.5% by mass or less of Mn, 0.5% by mass or less of Ni, 0.2% by mass or less of Sn, 0.2% by mass or less of Pb, 0.30% by mass or less of Ti, the balance being Al and other inevitable impurities, wherein a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material is 1% by mass or less. The ADC 20 has good mechanical strength, good castability, and further good electroplating properties. Therefore, the present inventors have considered that it would be promising as a base material of a slider for a slide fastener.
However, even if the slider has been produced by the die casting method using the ADC 12, the problem of cracking when caulking the pull tab attaching post has not been solved yet. It is known that the plastic workability is improved by suppressing an Fe concentration in the aluminum alloy, and it is thus considered that the method for reducing the Fe concentration is also adopted in the slider. However, in the casting of small parts such as the slider, iron casting parts are widely used, so that the contamination of Fe is inevitable. Therefore, the method for reducing the Fe concentration is not realistic.
Therefore, the present inventors have further investigated and found that Pb has had a significant adverse effect on the bending workability of the ADC 12. The content of Pb is defined as 0.2% by mass or less in the ADC 12. The commercially available ADC 12 has a Pb concentration of about 0.05% by mass, which concentration has already been decreased. However, the present inventors have found that by further suppressing the Pb concentration to 0.01% by mass or less, the plastic workability is remarkably improved. It is also possible to use general-purpose iron cast parts. Therefore, the technique for improving the plastic workability of the aluminum alloy by suppressing the Pb concentration can be excellent in practical utility. The present invention has been accomplished based on the above findings.
The present invention relates to a slider for a slide fastener as defined in claim 1.
According to the present invention, a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material is 1% by mass or less.
In another embodiment of the slider for the slide fastener according to the present invention, an Fe concentration in the inevitable impurities of the base material is 0.5% by mass or more.
In yet another embodiment of the slider for the slide fastener according to the present invention, a Zn concentration in the inevitable impurities of the base material is 0.1% by mass or less.
In still another embodiment of the slider for the slide fastener according to the present invention, an Mg concentration in the inevitable impurities of the base material is 0.1% by mass or less.
In yet another embodiment of the slider for the slide fastener according to the present invention, the base material at a base portion of the pull tab attaching post has an average value of Vickers hardness (Hv) of from 80 to 100.
In still another embodiment of the slider for the slide fastener according to the present invention, the pull tap attaching post has a bent portion at the base portion, and the base material at the base portion has an average value of Vickers hardness (Hv) of from 90 to 100.
In yet another embodiment, the slider for the slide fastener according to the present invention has a plating film on the base material.
In still another embodiment of the slider for the slide fastener according to the present invention, the plating film comprises a ground plating film containing one or more elements selected from the group consisting of Cu, Ni and Zn.
In yet another embodiment of the slider for the slide fastener according to the present invention, the base material is a die-cast product.
In another aspect, the present invention relates to a method for producing a slider for a slide fastener, as defined in claim 11.
In yet another aspect, the present invention relates to an article comprising the slide fastener according to the present invention.

Advantageous Effects of Invention

According to the present invention, it is possible to provide an aluminum alloy slider for a slide fastener, which has both practical strength and plastic workability. By using the aluminum alloy slider according to the present invention, the weight of the metal slide fastener can be reduced. Further, since element rows made of an aluminum alloy have already been put to practical use, the element rows can be used in combination with the aluminum alloy slider according to the present invention, so that it is possible to provide a metal slide fastener having a sense of unity in terms of the design. Furthermore, the slider for the slide fastener according to the present invention has an extremely decreased Pb concentration, and it can be said that a slider is also environmentally friendly.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an example of a perspective view of a slider according to an embodiment of the present invention.
FIG. 2 is an example of a cross-sectional view when a slider according to an embodiment of the present invention is cut along a center line in a right-left direction.
FIG. 3 is a front view showing an example of a pull tab attached to a slider body.
FIG. 4 is a schematic view showing an example of a slide fastener.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(1. Composition of Slider Base Material)

A base material of a slider for a slide fastener according to the present invention is made of an aluminum alloy based on ADC 21 and having an extremely low Pb concentration. Specifically, the slider for the slide fastener according to the present invention includes as a base material an aluminum alloy containing from 9.6 to 12.0% by mass of Si and from 1.5 to 3.5% by mass of Cu, the balance being Al and inevitable impurities, and has a Pb concentration in the inevitable impurities of 0.01% by mass or less, wherein a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material is 1% by mass or less. In a typical embodiment, the aluminum alloy contains 0.3% by mass or less of Mg, 1.0% by mass or less of Zn, 1.3% by mass or less of Fe, 0.5% by mass or less of Mn, 0.5% by mass or less of Ni, 0.2% by mass or less of Sn and 0.30% by mass or less of Ti, as typical inevitable impurities.
The use of the aluminum alloy based on the ADC 12 can allow practical strength required for the slider to be ensured. By decreasing the Pb concentration in the aluminum alloy based on the ADC 12 to 0.01% by mass or less, the plastic workability of the slider based on such an aluminum alloy is significantly improved. While not wishing to be bound by any theory, a mechanism for increasing the plastic workability due to extremely low Pb concentration would be considered as follows. If fine precipitates of Pb are present at crystal grain boundaries without dissolving in the aluminum alloy, cracking would tend to occur starting from the precipitates in a small part such as the pull tab attaching post of the slider, even if the Pb concentration is low. In the present invention, it is believed that the extremely low Pb concentration suppresses such an adverse effect due to such fine precipitates of Pb, thereby improving the plastic workability, particularly bending workability.
Furthermore, Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities are elements which increase the hardness and decrease the bending workability, although their effects are less than those of Pb. Therefore, the aluminum alloy base material used for the slider for the slide fastener according to the present invention, the total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material is 1% by mass or less. The total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti is more preferably 0.9% by mass or less, and still more preferably 0.8% by mass or less.
Among Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti, particularly desirable elements to be suppressed are Mg and Zn in terms of the bending workability. Therefore, in one preferred embodiment of the aluminum alloy base material used for the slider for the slide fastener according to the present invention, the Zn concentration is 0.1% by mass or less, and more preferably 0.05% by mass or less, and even more preferably 0.01% by mass or less. Further, in one preferred embodiment of the aluminum alloy base material for forming the slider for the slide fastener according to the present invention, the Mg concentration is 0.1% by mass or less, and more preferably 0.05% by mass or less, and even more preferably 0.01% by mass or less.
Although it is preferable that the concentration of Fe, which is the inevitable impurity, is decreased, Fe is also the main component for the Fe casting part as described above, so that in terms of increasing the industrial productivity, the slider desirably has sufficient plastic workability, particularly sufficient bending workability, even if the Fe concentration is not decreased. In this regard, the slider according to the present invention has the extremely decreased Pb concentration, so that it is possible to obtain the slider having practical plastic workability without paying much attention to the Fe concentration. Specifically, in one embodiment, the aluminum alloy base material forming the slider for the slide fastener according to the present invention may have an Fe concentration of 0.5% by mass or more, or 0.6% by mass or more, or 0.7% by mass or more, for example, from 0.5 to 1.0% by mass.

(2. Plating film)

Various plating films can be formed on the base material of the slider for the slide fastener according to the present invention for the purpose of imparting design properties, corrosion resistance and the like. The plating film can be formed by any known method and can be formed by, for example, electroplating or electroless plating. A type of the plating film includes, but not limited to, a Cu plating film, a Cu-Sn plating film, a Ni plating film, a Sn-Ni plating film, a Cr plating film, a Rh plating film, and a Pt plating film. Also, the plating film can have various ground plating films. For example, it is possible to have one or more ground plating films selected from the group consisting of Cu, Ni and Zn. Typical examples of the method for forming the ground plating film include a zincate treatment and an electroless plating method.
The thickness of the plating film is not particularly limited, but it can be, for example, a total thickness of from 1 µm to 10 µm, and typically a total thickness of from 2 µm to 6 µm.
Optionally, various surface treatments such as an anodizing treatment and a chemical conversion coating treatment may be performed, in addition to the plating.

(3. Structure of Slider)

A structural example of the slider for the slide fastener according to the present invention will be described. In the present specification, directions of the slider are defined as follows. A sliding direction of the slider is defined as a front-back direction, a direction where the slider slides so as to engage the element rows is defined as a forward direction, and a direction where the slider slides so as to disengage the element rows is a backward direction. Further, a direction perpendicular to a surface of a fastener tape is defined as an up-down direction, a direction from a lower blade toward an upper blade is defined as an upward direction, and a direction from an upper blade toward a lower blade is defined as a downward direction. Furthermore, a direction parallel to a surface of a fastener tape and orthogonal to the sliding direction of the slider is defined as a right-left direction, and when the slider slides forward as viewing the slider from the above, a right side facing the forward direction of the slider is defined as a right direction, and a left side facing the forward direction is defined as a left direction. Moreover, a surface parallel to the front-back direction and the right-left direction are referred to as a horizontal surface.
Referring now to FIGS. 1 and 2, they show a perspective view and a cross-sectional view of an embodiment of the slider for the slide fastener according to the present invention, respectively. The slider is a die-cast product based on the above aluminum alloy and including a slider body (100) and a pull tab attaching post (120) formed on the slider body (100).
The slider body (100) includes, as a basic structure, an upper blade (101); a lower blade (102); left and right side walls (105, 106) having guide grooves (103, 104) for fastener tapes; a connecting post (109) provided at a front end portion of the slider body (100) and connecting the upper blade (101) and the lower blade (102); and one rear port for a pair of element rows (110) engaged with each other to enter and exit. A pair of front ports (107, 108) and the single rear port (110) are connected to each other through a substantially Y-shaped element guiding path formed inside the slider body (100) so as to branch in the right-left direction along each guide groove (103, 104).
The upper surface of the upper blade (101) is provided with a pull tab attaching post (120). In the present embodiment, the pull tab attaching post (120) has a gate shape with one end fixed in a cantilevered manner and extending in the sliding direction, but not limited thereto, it may be a pull tab attaching portion having any shape known in the art. Further, referring to FIG. 3, a pull tab (201) having a hole portion at one end is prepared, and the pull tab (201) can be rotatably attached to the pull tab attaching post (120) through the hole portion. Furthermore, a base portion of the pull tab attaching post (120) is subjected to a bending process, so that a tip of the pull tab attaching post (120) is caulked downward (namely, in a direction of approaching the upper blade) such that the pull tab (201) cannot easily come out of the pull tab attaching post (120). The base portion (121) of the pull tab attaching post (120) which has undergone the plastic deformation by the bending process has a plastically deformed structure.
As a pair of element rows in a separated state enters the two front ports (107, 108), the element rows initially divided into the right and left are gradually brought close to each other while passing through the substantially Y-shaped element guide path, and the element rows are eventually engaged with each other. The pair of element rows engaged exits the common rear port (110). The user can slide the slider while gripping the pull tab (201), thereby controlling the engagement and disengagement of the element rows.

(4. Vickers Hardness of Pull Tab Attaching Post)

The base portion of the pull tab attaching post is the most prone to cracking when caulking the pull tab attaching post. Therefore, it is important to control hardness at the base portion. If the pull tab attaching post is formed using the commercially available general ADC 12, the hardness at the base portion will be too high, which causes a problem that cracking is likely to occur when caulking the pull tab attaching post. However, according to the slider according to the present invention, the impurity concentration of Pb or the like which will adversely affect the bending workability is strictly reduced and the hardness of the base portion of the pull tab attaching post can be appropriately reduced. Therefore, there is an advantage that cracking is unlikely to occur when caulking the pull tab attaching post.
In one embodiment of the base material of the slider for the slide fastener according to the present invention, an average value of the Vickers hardness (Hv) at the base portion of the pull tab attaching post is from 80 to 100. In another embodiment of the base material of the slider for the slide fastener according to the present invention, it includes a bent portion generated by caulking the pull tab attaching post at the base portion of the pull tab attaching post, and in this embodiment, an average value of the Vickers hardness (Hv) of the base material at the base portion of the pull tab attaching post can be, for example, from 90 to 100, and typically from 95 to 100. In yet another embodiment of the base material of the slider for the slide fastener according to the present invention, it is in a state before caulking the pull tab attaching post and the Vickers hardness (Hv) of the base material at the base portion of the pull attaching post in that state can be from 80 to 95, and typically from 85 to 95. It is suitable that the caulking process is carried out such that the average value of the Vickers hardness (Hv) of the base material at the base portion of the pull tab attaching post is increased by about 5 to 10.
As used herein, the base portion of the pull tab attaching post refers to a portion of the pull tab attaching post located above a boundary line in a range from a front end to a rear end of the boundary line, when cutting the pull tab attaching post along a center line in the right-left direction and observing the resulting cross section, and drawing the boundary line between the pull tab attaching post and the outer surface of the slider body along the outer surface of the slider body. As an example, the range of the base portion (121) of the pull tab attaching post is indicated by a dotted frame in FIG. 2.
In the present invention, the average value of Vickers hardness (Hv) at the base portion of the pull tab attaching post is measured according to JIS 2244: 2009 by the following procedure. The slider is filled in a resin and polished using emery paper such that a cross section of the pull tab attaching post at the center of the right-left direction can be obtained. Then, in order to measure the hardness, mirror-polishing is performed using a diamond paste having a maximum diamond particle diameter of 1 µm. After polishing, a large number of Vickers hardness (Hv) on the central cross section of the pull tab attaching post in the right-left direction are measured to calculate an average value. In Examples, the Vickers hardness was measured at about 90 points with a load of 100 gf, a loading time of 15 sec, and a measuring interval of 0.5 mm using an FM-700 Vickers hardness meter available from FUTURE-TECH CORP., and an average value thereof was calculated.

(5. Method for Producing Slider)

In one embodiment, a method for producing a base material of the slider for the slide fastener according to the present invention includes a step of integrally forming a base material of the slider for the slide fastener by a die casting method using the aluminum alloy as a raw material, the slider including a slider body and a pull tab attaching post formed on the slider body; and a step of attaching a pull tab involving plastically deforming the pull tab attaching post.
The composition of the aluminum alloy used as a raw material is omitted, because it is as described in "1. Composition of Slider Base Material" including the preferred embodiment. However, a raw material having a purity as high as possible is preferably used in order to prevent contamination of impurities such as Pb. If the ADC 12 aluminum alloy which is generally commercially available is used, the amount of impurities does not satisfy the criteria intended by the present invention.
When integrally forming the base material of the slider by the die casting method, it is desirable to install overflow and air vent so that blow holes and shrinkage holes do not occur near the surface.
The plastic deformation of the base portion of the pull tab attaching post in the step of attaching the pull tab leads to an increase in the hardness at the base portion of the pull tab attaching post. Appropriate hardness before and after the plastic deformation can allow both of the bending workability and the strength to be achieved. The appropriate hardness before and after the plastic deformation is as discussed in "4. Vickers Hardness of Pull Tab Attaching Post".
Typically, the step of attaching the pull tab can be carried out by inserting the pull tab attaching post into the attachment hole formed at one end of the pull tab and then bending the base portion of the pull tab attaching post to caulk downward the tip of the pull tab attaching post.
The base material of the slider for the slider fastener according to the present invention may optionally be subjected to various surface treatments before and/or after the step of attaching the pull tab. For example, a smoothing treatment, a rust prevention treatment, a coating treatment, a plating treatment and the like can be carried out.

(6. Slide Fastener)

An example of the slider fastener including the slider for the slide fastener according to the present invention is shown in FIG. 4. As shown in FIG. 4, the slide fastener includes a pair of fastener tapes (1) each having a core portion (2) formed on one side edge; an element (3) row caulked and fixed (attached) to the core portion (2) of each fastener tape (1) and arranged at a predetermined space on the core portion 2; an top stop (4) and a bottom stop (5) caulked and fixed to the core portion (2) of each fastener tape (1) at the upper end and the lower end of the element (3) row, respectively; and a slider (6) arranged between a pair of the opposing element (3) rows and slidable in the up-down direction so as to engage and disengage the pair of the element (3) rows. An article in which the element (3) row has been attached along one side edge of one fastener tape 1 is referred to as a slide fastener stringer, and an article in which the element (3) rows attached to the core portions 2 of a pair of the fastener tapes 1 have been engaged with each other is referred to as a slide fastener chain (7). It is noted that the bottom stop (5) may be an openable, closable and fittingly insertable tool including an insert pin, a box pin and a box body, so that the pair of slide fastener chains can be separated by separating operation of the slider.
The slide fastener can be attached to various articles, and particularly functions as an opening/closing tool. The articles to which the slide fastener is attached include, but not limited to, daily necessities such as clothes, bags, shoes and miscellaneous goods, as well as industrial goods such as water storage tanks, fishing nets and space suites.

EXAMPLES

Hereinafter, Examples of the present invention are illustrated, but they are provided for better understanding of the present invention and its advantages, and are not intended to limit the present invention.

In Example 1, a high-purity bare metal was purchased from a raw material maker. The bare metal had a composition in which Si was 10.7% by mass, Cu was 1.8% by mass, the balance were Al and inevitable impurities, and a Pb concentration in the inevitable impurities was 0.01% by mass or less, and a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti was 1% by mass or less.
In Comparative Example 1, a secondary bare metal of ADC 12 having a composition in which Si was 10.7% by mass, Cu was 1.8% by mass, the balance were Al and inevitable impurities was purchased from a raw material maker.
Each of the purchased bare metals was melted in a casting machine made of iron, and then integrally formed into a slider base material (a size for a chain width of 12 mm defined in JIS S 3015: 2007) having a shape shown in FIG. 1 by the die casting method (however, in a state before caulking the pull tab attaching post, the distance between the tip of the pull tab attaching post and the upper blade was greater than that in FIG. 1).

A chemical composition of each slider base material obtained by the above producing procedure was measured by an ICP method (Inductively Coupled Plasma Method). The results are shown in Table 1. In Example 1, it is found that the concentrations of the inevitable impurities such as Pb are decreased as compared with Comparative Example 1.

[Table 1]

Result of Composition Analvsis (unit: % bv mass)
Test No.	Pb	Si	Cu	Fe	Mg	Zn	Sn	Ni	Al	Mn	Cr	Ti
Example 1	< 0.01	10.7	1.8	0.72	< 0.01	< 0.01	< 0.01	< 0.01	86.7	< 0.01	< 0.01	< 0.01
Comparative Example 1	0.06	10.5	1.7	0.74	0.22	0.73	<0.01	0.06	85.7	0.17	0.04	0.04

Subsequently, the entire surface of the slider base material was subjected to a zincate treatment (a thickness of about 1 µm), and a copper film (a thickness of about 20 µm) was then formed by copper sulfate plating as a ground, and a copper-tin plating film (a thickness of about 1 µm) was further formed by electroplating.

Each plated slider produced by the above procedure was subjected to a caulking process of the pull tab attaching post. The caulking process was carried out using a long-nose pliers under conditions where a distance from the tip of the pull tab attaching post to the surface of the slider body was shortened from 3 mm to a contacted state. An average value of the Vickers hardness (according to JIS Z 2244: 2009, the load was 100 gf) at the base portion of the pull tab attaching post before and after the caulking process was determined by the procedure as described above using the Vickers hardness meter. The results are shown in Table 2. It is found that in Example 1, the Vickers hardness at the base portion of the pull tab attaching post is appropriately lower than that of Comparative Example 1. Table 2

Vickers Hardness (Hv)

Before Caulking After Caulking

Test No. Average Value Average Value

Example 1 90 98

Comparative Example 1 105 108

Five plated sliders were prepared for each of Example 1 and Comparative Example 1 by the same procedure as described above, and each slider was subjected to the caulking process to investigate whether or not cracking occurred at the base portion of the pull tab attaching post. The caulking conditions are the same as those of the hardness test. As a result, in Comparative Example 1, cracking occurred at the base portion of the pull tab attaching post for one of five sliders, whereas in Example 1 no cracking occurred.

After inserting the pull tab attaching post of each plated slider of Example 1 and Comparative Example 1 produced by the same procedure as described above into the attachment hole formed at one end of the pull tab, the caulking process was performed on the pull attachment post to movably attach the pull tab having a shape shown in FIG. 3 to the surface of the slider body. Slider tab pull off strength was measured for each slider with the pull tab attached in accordance with JIS S 3015: 2007. The slider tab pull off strength measures resistance of the slider when a load is applied to the pull tab and the lower surface of the slider body in the slider. The maxim load when applying a load by pulling the pull tab of the slider from the upper surface of the slider and further applying a load to the lower surface of the slider body until the pull tab of the slider is removed or a part constituting the slider is broken and separated is defined to be the slider tab pull off strength. Ten measurements were performed for each of Example 1 and Comparative Example 1, and an average value was determined to be a measurement value. The results are shown in Table 3. Table 3 also shows the slider tab pull off strength when a slider having the same shape was produced with a conventional zinc alloy (a material of the slider base material is a zinc alloy ZDC 1 defined in JIS H 5301: 2009) for reference. It is found that the slider according to Comparative Example 1 has poorer strength as compared with the conventional zinc alloy slider. On the other hand, it is found that the slider according to Example 1 has strength comparable to that of the conventional zinc alloy slider. [Table 3]

Test No. Slider Tab Pull Off Strength (N)

Example 1 581

Comparative Example 1 518

Reference Example (Zinc alloy) 574

DESCRIPTION OF REFERENCE NUMERALS

1 fastener tape
2 core portion
3 element
4 top stop
5 bottom stop
6 slider
7 slide fastener chain
100 slider body
101 upper blade
102 lower blade
103, 104 guide groove of fastener tape
105, 106 side wall
107, 108 front port
109 connecting post
110 rear port
120 pull tab attaching post
121 base portion of pull tab attaching post
201 pull tab

Claims

A slider for a slide fastener, the slider comprising a slider body (100) and a pull tab attaching post (120) formed on the slider body (100), the slider comprising an aluminum alloy as a base material, the base material containing from 9.6 to 12.0% by mass of Si; from 1.5 to 3.5% by mass of Cu; and 0.01% by mass or less of Pb as an inevitable impurity; the balance being Al and other inevitable impurities, wherein a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material is 1% by mass or less.
The slider for the slide fastener according to claim 1, wherein an Fe concentration in the inevitable impurities of the base material is 0.5% by mass or more.
The slider for the slide fastener according to claim 1 or 2, wherein a Zn concentration in the inevitable impurities of the base material is 0.1% by mass or less.
The slider for the slide fastener according to any one of claims 1 to 3, wherein an Mg concentration in the inevitable impurities of the base material is 0.1% by mass or less.
The slider for the slide fastener according to any one of claims 1 to 4, wherein the base material at a base portion (121) of the pull tab attaching post (120) has an average value of Vickers hardness (Hv) of from 80 to 100.
The slider for the slide fastener according to claim 5, wherein the pull tap attaching post (120) has a bent portion at the base portion (121), and wherein the base material at the base portion has an average value of Vickers hardness (Hv) of from 90 to 100.
The slider for the slide fastener according to any one of claims 1 to 6, wherein the slider has a plating film on the base material.
The slider for the slide fastener according to claim 7, wherein the plating film comprises a ground plating film containing one or more elements selected from a group consisting of Cu, Ni and Zn.
The slider for the slide fastener according to any one of claims 1 to 8, wherein the base material is a die-cast product.
A method for producing a slider for a slide fastener, the method comprising:
- integrally forming a base material of a slider for a slide fastener by a die casting method using an aluminum alloy as a raw material, the base material containing from 9.6 to 12.0% by mass of Si; from 1.5 to 3.5% by mass of Cu; and 0.01% by mass or less of Pb as an inevitable impurity; the balance being Al and other inevitable impurities, and a total concentration of Fe, Mg, Zn, Sn, Ni, Mn, Cr and Ti in the inevitable impurities of the base material being 1% by mass or less; the slider comprising a slider body (100) and a pull tab attaching post (120) formed on the slider body (100); and

- attaching a pull tab (201) involving plastically deforming the pull tab attaching post (120).
A slide fastener comprising the slider for the slide fastener according to any one of claims 1 to 9.
An article comprising the slide fastener according to claim 11.