JPH0360291B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the attachment of fastening elements, in particular to Velcro-like self-gripping tapes which have a gripping device such as a hook on one side and are shaped on the other side.

In particular, the invention relates to the attachment of such tapes to molded foam products, such as automobile seats or backrests. This tape is designed to hold products such as seat covers with additional gripping means by means of its gripping means.

The present invention also relates to a self-gripping tape designed to be attached to a product being molded during a molding operation.

When a tape has to be applied to such products by conventional equipment during molding, the tape is first placed inside the mold so as to abut the inner surface of the mold cavity; Adhere temporarily.

The tape can be used with temporary adhesives or other adhesives before and during molding.
It is held in place in a satisfactory manner by various devices, such as magnetic or mechanical devices.

However, a difficulty that has not yet been completely satisfactorily resolved is that the liquid molding material seeps between the inner surface of the mold and its tape before it reaches its final chemical or physical form. The object is to prevent the gripping hooks arranged upside down on the outside of the mold from becoming jammed and reducing the gripping force of those hooks.

The main aim of the invention is to solve this difficulty in a satisfactory technical and economical manner.

The tape according to the invention therefore has a base, and one side of the base is provided with a gripping device that is turned upside down toward the outside of the mold. The tape is placed against the inner surface of the mold along the edges and portions of the periphery that are free of gripping devices. Between the inner surface of the mold and the base having the gripping device there is a thin continuous protective film that covers the gripping device and extends to the edges to form a seal that protects the gripping device during molding. do.

The edges of the protective film are recessed from the edges of the base, so that the base adheres directly to the inner surface of the mold.

More preferably, the tape is stretched;
At its two small ends, the tape receives and holds the corresponding ends of the protective membrane by gluing, especially by ultrasonic welding. The gripping device collapses between the surface and the membrane in this part.

According to the invention, a method for attaching such a tape to a product to be molded during a molding operation is characterized in that: That is, a tape with a protective film is placed in the mold cavity, then the molding temperature is set to a temperature that does not affect the protective film, and the protective film is
It is removed after the molding material has become chemically and physically stable.

According to one embodiment, the protective film is made of a material that disintegrates at a higher temperature than the temperature at which the molding material is stable. As long as the molding material is still fluid, the heating increases during the molding operation so that the molding material cannot seep between the base of the tape and the disintegrated protective film. After the molding material has stabilized, the membrane collapses and, under the influence of the rising temperature, it at least partially disappears, exposing the gripping device.

The type of protective film is selected according to the characteristics of the molding material.

Thus, according to a preferred method of the invention, the product is molded in cold form. That is, the foam solidifies from about 50°C (eg polyether). Polyolefin membranes can also be used, in particular rigid or flexible polyethylenes which disintegrate from 100°C and cellulose acetate which disintegrates from 60°C.

This protective film is very thin, a few hundredths of a millimeter (for example, 0.02 mm), and it shrivels during collapse, leaving only a small amount of decay products behind.
Even if it were to become stuck between the gripping members, it would not significantly reduce the gripping force.

Thermal breakdown of the protective film can be done as part of the molding cycle, at its final stage, or after molding.
That is, this is done after the molded product has been removed from the mold and, if possible, cooled. In this case, the disintegration takes place by short-term heating, for example with a flame.

According to a second embodiment of this process, the temporary protective coating is adhered with its edges to at least the longitudinal edges of the face or side of the base with the gripping device. These longitudinal edges have no gripping devices;
After molding, the membrane can be easily peeled away from the surface to expose the gripping device.

Removal of the membrane can be accomplished by peeling off the glue or by splitting the membrane at the junction between the adhesive portion and the remaining portion of the membrane. This division can also be done by tearing or cutting.

The initial glueing of this membrane is carried out by applying adhesive or by physical-chemical action, in particular by ultrasonic welding by crushing the gripping device of the glued part.

A fairly rigid padding material, for example made of metal, can advantageously be placed between the central non-adhered part of the membrane and the top of the gripping device covered by the membrane. The purpose of this padding material is, on the one hand, to make the composite assembly of tape and membrane rigid for molding, and on the other hand, to facilitate the removal of the membrane after molding. If the padding is made of magnetic material, another use for it is to assist the magnets designed into the mold and to retain the tape within the mold.

Preferably, the membrane can also be applied across both ends of the tape in the same manner.

A method of attaching the aforementioned tape to a molded product without thermally destroying the membrane is as follows. That is, the edge portion of the protective film is temporarily attached to at least the longitudinal edge portion of the surface of the base having one gripping member.
These longitudinal edge portions are free of the gripping members.

- Fitting the thus protected tape into the mold.

- Complete the molding operation.

- Removing the assembly consisting of the molded product and the tape attached to it;

- removing the film on said side of the tape to expose the gripping member;

The invention will be better understood by reference to the following description and accompanying drawings.

Referring now specifically to the drawings, FIGS. 3 and 7 are partial views of a mold 1, for example made of aluminum, for molding the product 2 shown in FIGS. 4 and 8. This molded product 2, in the method of a preferred embodiment of the invention, is a seat or backrest made of polyurethane foam of the polyether type for a motor vehicle seat.

The product is adapted to accept a cover (Figs. 4 and 8) 3, such as a seat cover. The molded product 2 holds the cover 3 by a fixing member consisting of a tape 4, which is firmly attached to the molded product 2 and has a hook 5 shaped, for example, on the upside down surface facing the cover 3. These gripping devices have for that purpose a cover 3 with loose fibrous non-woven patches 6.
It is supposed to work together with the back.

During the molding operation, tape 4 is applied in a vertical manner.
It is attached to the outer surface of the molded product 2. For this,
As shown in FIG. 3, the tape 4 is temporarily attached to the inner surface 7 of the molding hole 8 of the mold 1. As shown in FIG. For such fixing, the tape 4 has, on its outer surface with gripping hooks 5, two longitudinal edge parts without hooks 5, which are also coated with adhesive 9 (first to fourth
The adhesive is protected by a thin film 10 so that it does not come off when the tape 4 is applied to the inner surface 7 of the mold. Furthermore, referring to the method embodiments of FIGS. 5-8, the tape 4 can also be held by a magnetic device by means of magnets embedded in the walls of the mold.

In order to attach tape 4, mold 1 is
It has a cavity 11 for receiving the hook 5 and, if possible, two small side cavities 1 on each side of this cavity for receiving the marginal parts of the tape 4.
It is preferable to have 2. These marginal parts are
If coated with adhesive, peel-off protective film 1
Set it to 0. The depth of the void, that is, the main groove 11 is
If the hook 5 is in contact with the bottom of the mold 1 and there is a side cavity, the tape surface 13 opposite to the surface having the gripping hook 5 is made to be at the same height as the inner surface of the mold 1. The depth of the cavity or side groove 12 is approximately equal to the thickness of the tape 4. In this way, the side 13 of the tape 4 opposite the side with the hook 5 is level with the inner surface 7.
Furthermore, the tape 4 is held on the one hand against the mold 1 via its side parts located in the cavity 12;
On the other hand, if necessary, in the center, empty space 11
It is held via a hook 5 located at the bottom of the holder.
Thus, while the molding material is foaming, the pressure thereon against the tape 4 does not deform the tape.

Surface 13 of tape 4 facing inside of mold 1
is at the same height as the inner surface of the mold, so that this base protrudes above the finished product 2, as shown in FIGS.

In order to ensure a good adhesion between the tape 4 and the molding material, the fixing member 14 is arranged approximately at right angles from the tape surface 13 towards the inside of the mold 1. Each fastening member, together with a flared head 16, has a shaft or leg 15 with a free end remote from the surface 13.
It consists of The head 16 can be of any suitable shape.

Alternatively, instead of the fixing member 14 it is also possible to use a suitable structure, such as, for example, a jersey, a screen or something for fixing the molding material.

During the molding operation, when the mold material is still liquid, a thin protective film 17 is provided to prevent the mold material from penetrating between the hooks 5 and sticking there, reducing the gripping force of the hooks 5. Covering hook 5 (Figures 1-3, Figures 5-8),
Cover the entire length of the tape between the edges of the tape.

The membrane 17 can also be attached to the marginal longitudinal part of the surface 13 by means of a suitable device, by means of an adhesive coating, for example by welding, in particular by ultrasonic welding, such as by crushing the hook 5 of the soaking part. This latter method is preferably used. This is because one or two rows of hooks 5 can be collapsed during the welding operation in order to attach the membrane 17 to the tape 4. Due to the rigidity and narrowness of the base, adhesive can also be omitted on the small sides to glue the tape 4 to the mold. For example, in the case of a wide tape, one could consider leveling the tape 4 by removing several rows of hooks 5 and attaching the edges of the membrane 17, as on the long side.

In the embodiment of FIGS. 1 to 4, in order to leave free boundaries for the adhesive 9 and its protective film 10,
The membrane 17 ends short of the opposite longitudinal sides of the surface 13.

According to the variant of FIGS. 5 to 8, the membrane 17 reaches the outer contour of the tape 4, in which case the tape 4 is not applied to the mold 1 at all, but is magnetically retained, as will be explained later. be done.

According to a feature of the invention, membrane 17 is made of a material that physically and chemically disintegrates at temperatures above the temperature at which the molded article physically and chemically solidifies.

For example, if the molded product 2 is a polyether foam that solidifies at about 50° C. (cold process), the polyolefin film 17 is used. On the other hand, flexible or rigid polyethylene, which disintegrates at 100°C, or cellulose acetate, which disintegrates at 60°C, can also be used.

The membrane 17 is very thin, a few hundredths of a millimeter, for example 0.02 mm.

Before the tape 4 is inserted into the mold 1 (FIGS. 1 and 2), it is covered with a membrane 17 that surrounds and protects the hook 5 like a cocoon.

Mold the tape 4 with the film 17 attached (Figure 3)
When placed on the tape, the tape is temporarily held in place by adhesive 9 or other similar means. Hook 5
is a cavity 1 covered with a membrane 17 and having a through hole 18
Extend to 1.

During the molding process, liquid molding material is introduced into the mold cavity 8 and when the temperature is raised by controlled heating, the material assumes its shape and at the same time solidifies in its chemical structure. While the material is liquid or viscous, i.e. at low temperatures, membrane 17 not only communicates with surface 13, but is in contact with surface 13.
3 and which surrounds and protects the hook 5, material is prevented from entering into the closed space 19 formed therewith. The hook 5 is thus protected as long as the molding material is liquid. As the temperature continues to rise under external regulation, the material of membrane 17 begins to disintegrate. If the film is thin, this collapse will cause it to curl. This is a well-known phenomenon and results in only a small amount of residual material. This residue, even if it falls into the hook 5, is so small that it will not become clogged and reduce the gripping force of the hook 5.

At the end of the molding process, at least a portion of the membrane 17 disintegrates, and gradually completely. The decay products fall as solid parts onto the surface 13, onto the hook 5 and onto the cavity surface 11, so that when not molded, the hook 5 is completely clean and requires no extra expensive cleaning. The hook 5 can later grip the cover 3 without any work.

Thus, by virtue of the invention providing a membrane 17 that creates a sealed enclosure, the hook 5 is safely protected from becoming clogged with molding material. Due to special features,
This film automatically collapses upon heating after the molding material has solidified.

According to another embodiment of the invention, the material of the protective film remains unaffected during the molding operation. This film 1
7 is later destroyed by chemical, mechanical, or thermal means. In thermal means, the finished molded product 2 with the tape 4 provided with the membrane 17 is subjected to, for example, a short intense surface heating, in particular a flame for the surface treatment of the product 2, and at the same time the membrane 17 is Disintegrates due to heat.

According to another variant shown in FIGS. 5-8,
In the space 19, between the top of the hook 5 and the membrane 17, a fairly rigid padding material 20 is arranged. This stuffing has the same width (FIG. 5) and the same length (FIG. 6) as the part of the surface 13 with the hook 5. This stuffing material is a metal sheet with a thickness of a few tenths of a millimeter. Since it is made of, for example, an iron-based sheet or a magnetic material, it is attracted by a magnet 21 embedded in the bottom of the cavity 11 of the mold 1. This secures the tape 4 during the molding operation.

In addition to being used to retain the tape 4 within the cavity 11, the padding material 20 also strengthens the composite assembly of the tape 4 itself and the membrane 17 and aids in its positioning within the mold 1. make it easier to Furthermore, after the molding operation, it also facilitates the removal of the membrane 17 from the tape 4 fixed to the molded product 2.

The membrane 17 can be removed by pulling the edges apart or tearing or cutting. If the adhesion between the membrane 17 and the edge portion of the surface 13 is not very strong, the separation is performed so that the tongue of the membrane 17a (FIG. 8) corresponding to the unremoved residue of the membrane 17 is removed.
If there is a possibility of remaining on each of the vertical edge portions of the surface 13, tearing is performed if there is no problem. In either such case the membrane 17 is applied to one of the small sides of the tape 4 and then the padding material 20
The overlapping edges of the membrane 17 and the membrane 17 grip each other,
The assembly is gradually lifted while peeling, so that the membrane 17 is removed with or without the marginal portion of the membrane that was initially applied to the surface 13. In these operations, the marginal portions of the padding material 20 facilitate the removal of the membrane 17. When the membrane 17 splits, the longitudinal edges of the padding material 20 are in effect two supporting edges, ie, cutting edges, so that it is torn along and near the edges. There is. In the third case, the cutting force is guided along the longitudinal edges of the padding 20 or in close proximity to the glued edges of the membrane 17 in order to make the separation very clean. Repeat this same procedure for the short side of tape 4.

The tape 4, before being inserted into the mold 1 (FIGS. 1 and 2), is covered with a membrane 17 which surrounds the hook 5 like an envelope or cocoon in an enclosed space 19; Protect.

Tape 4 with membrane 17 attached is molded (Figure 7)
When placed inside, the tape is temporarily held by adhesive or magnets 21, and the hook 5, covered by the membrane 17, extends into the cavity 1 with a through hole 18.

During the molding operation, the liquid molding material is introduced into the molding cavity 8 and, by controlled heating, its temperature is increased so that the material gradually solidifies in its shape and at the same time in its chemical structure. . During molding, the membrane 17 prevents material from seeping into the void 19. The hook 5 is thus protected from penetration of the molding liquid.

Naturally, the membrane 17 is selected from a material that can withstand the molding temperature.

At the end of the molding operation, tape 4 is applied and membrane 17
The product 2 with the attached product is taken out from the mold 1. Membrane 17 is then removed as described above.

[Brief explanation of drawings]

1 is a cross-sectional view of a tape according to a first embodiment of the present invention, FIG. 2 is a partial vertical cross-sectional view of the end of the tape of FIG. 1, and FIG. 3 is a cross-sectional view of the tape of FIG. A similar view showing the tape attached to the inner surface of the mold before molding. Figure 4 is a similar diagram to Figure 1.
Figure 3 shows a finished molded product with a gripping tape for the cover. 5 to 8 are similar views to FIGS. 1 to 4, respectively, and correspond to the second embodiment of the present invention. Explanation of symbols, 1...mold, 2...molded product, 3...cover, 4...tape, 5...hook, 6...fibrous nonwoven patch, 7...inner surface of molding hole, 8... Molding hole, 9...Adhesive, 10...Membrane,
11...Mold void, 12...Small side void, 1
3...Tape surface, 14...Fixing member, 15...
Shaft portion, 6... Head, 17... Protective film, 19...
Closed space of mold, 20...filling material, 21...
magnet.

Claims (1)

Claims: 1. characterized by having a base supporting on one side several rows of hook-like protrusions that harmoniously and releasably couple with a loose fibrous nonwoven patch to form a fixation assembly; In the mold fixing member, a temporary thin protection that covers and surrounds the hook-like protrusion in order to protect the hook-like protrusion from being clogged with molding liquid when the fixing member is molded into a molded product. membrane, whereby the hooks are virtually unclogged by solidified foam material at the end of the molding process, without an intermediate step of removing the solidified foam material from the hooks. An improved body characterized in that it is ready to accept woven patches. 2. Claim 1, wherein the protective film is attached to the base with an adhesive.
Fixing member described in section. 3. The fixing member according to claim 1, wherein the protective film is attached to the base by ultrasonic welding. 4. The tape is of the elongated type and is characterized in that it is provided at each end with a hook-free end portion so as to have a portion for receiving and retaining a corresponding end of the protective membrane. , a fixing member according to claim 1, 2 or 3. 5. Both edges of the protective film are offset inwardly, at least in the longitudinal direction, with respect to the respective peripheral edge portions of the base, thus allowing the base to be adhered directly to the inner surface of the mold. A fixing member according to claim 1, 2, or 3, characterized by: 6. Anchoring member according to claim 1, characterized in that it is elongated with opposite end portions adapted to receive corresponding marginal portions of the protective membrane. 7. Fixing according to claim 1 or 6, characterized in that the membrane is adapted to be removed from the base after completion of the molding process in order to expose the row of hook-like protrusions. Element. 8. Claim 6, characterized in that a relatively rigid filling material is interposed between the protective film covering the hook-like protrusion and the mold during the molding process.
Fixing member described in section. 9. Claim characterized in that the padding material is made of a magnetic metal that cooperates with magnets supported by the mold, so that the tape is magnetically retained within the mold during the molding process. The fixing member according to item 8. 10. The fixing member according to claim 8 or 9, wherein the padding material has the same width and length as the base portion where the hook-like protrusion is present. 11. Fixing member according to claim 8, characterized in that the longitudinal sides of the stuffing material support the fixing member during removal of the membrane after molding. 12. The fixing member according to claim 1, wherein the protective film belongs to the group consisting of polyolefin, polyethylene, and cellulose acetate. 13 The protective film is applied after the molded product has hardened.
Fixing member according to claim 1, characterized in that the protective film is adapted to be decomposed by heating during the molding process, leaving only a small amount of waste. 14. Claim 7, wherein the protective film is decomposed by intense heating for a short period of time after the fixing member and molded product are taken out of the mold. Fixed member as described. 15. The fastening member is of a type characterized in that it has a base supporting a number of rows of hook-like protrusions that are releasably joined in unison with a loose fibrous non-woven patch to form a fastening assembly. a. A thin protective film is attached to the fixed member to protect and surround the hook-like protrusion, and the protective film is formed of a heat-sensitive material that collapses when heated. b. placing a length of fixing member in the mold at a position such that the hook-like protrusion is exposed on the surface of the finished molded product; c. curing the molding fluid to form a solid; and d. molding. During curing of the product, applying heat to the protective film to cause it to collapse and expose the hook-like protrusions for a conformable, releasable bond with the non-woven patch. How to attach a fixing member to a product. 16. Claim 1, further comprising the step of continuously fixing the periphery of the protective film to the periphery of the base that supports the hook-like protrusion.
The method described in Section 5. 17 The step of heating the protective film is to harden the molding liquid to a solid state, and after the molding liquid has solidified enough to prevent the molding liquid from leaking into the area occupied by the hook-like projections, the protective film is heated to cover the hook-like projections. 16. A method according to claim 15, characterized in that the mold is heated in order to disintegrate the protective film. 18. said fixation member having a base supporting a number of rows of hook-like protrusions that harmoniously and releasably couple with a loose, fibrous non-woven patch to form a fixation assembly; A thin protective film is attached to the fixed member to protect and surround the hook-like protrusion, and the protective film is
be made of a heat-sensitive material that disintegrates when heated; b. fixed for a certain length in a position within the mold such that the hook-like protrusion is exposed on the surface of the finished molded product; c) curing the molding liquid to form a solid object at a temperature above the temperature at which the protective film collapses; d) heating the protective film after the molding step to cause it to collapse; and exposing said hook-like protrusions for harmonious and releasable engagement with a non-woven patch. 19. The step of heating the protective film comprises directly applying a flame to the protective film for a time sufficient to collapse the film without damaging the base or the hook-like protrusions. A method according to claim 18. 20. The method of claim 18, wherein the step of curing the molding fluid to form a solid comprises cold curing the molded article. 21. The method according to claim 18, wherein the protective film is removed from the fixing member after the fixing member is removed from the mold. 22. The method according to claim 21, characterized in that the protective film is removed by peeling off the fixing member from the mold. 23. Claim 21, characterized in that the protective membrane is removed by cutting or tearing, thereby leaving a small piece of the membrane stuck on each of the longitudinal end portions of the base. The method described in section.