SEALED PACKAGE AND METHOD OF MAKING

Abstract

A sealed package (10) encloses a pad (14) which has an impervious backing layer which may optionally be the base layer (10b) of the package (10). At least the interior of the package (10) and the sealed pad (14) are made of materials which are substantially free of micro-contaminants. The package is openable by separating the cover layer (1 Oa) from the base layer (10b) and thereby breaking the seal (12). The pad (14) may be dry or it may be impregnated with any suitable treatment substance, such as a solvent, which facilitates cleaning and which dissipates electrostatic charges. When the sealed pad (14) is dry, a suitable liquid or gel treatment substance, such as a solvent, may be applied to the pad or to a portion of it. A retainer hole (20) may be provided in the package (10) in the extra-peripheral area (11) outside the seal (12) to hold an optic fiber connector with which the package (10) may be sold as a unit.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is concerned with a wipe which is useful for cleaning or otherwise treating various objects, in particular, optic fiber ends, optic fiber connectors and the like. More specifically, the present invention concerns a wipe having an impervious backing layer and which is contained in a sealed, impervious package, and is otherwise configured to eliminate or at least drastically reduce contamination by trace oils and/or micron-size contaminates including dust motes and the like.

2. Related Art

Sealed foil packages containing gauze or other pads soaked with a liquid such as alcohol are well known. For example, in the medical field, alcohol-soaked gauze pads are sealed within impervious foil packages to protect the pads from contamination and prevent evaporation of the alcohol. The packages are opened only at the point of use, e.g., to swab a site on a patient's body to sterilize the site prior to an injection or other procedure.

For example, U.S. Pat. No. 5,320,217, issued Jun. 14, 1994 to M. D. Lenarz and entitled “Wet Swab Captured Package”, discloses a sealed package containing a moistened pad. As best seen in FIGS. 1 and 2, an absorbent pad 18 is enclosed within the package 10 which contains a transverse seal line 20 which grips pad 18 and prevents it from being readily removed from the package when head portion 22 of package 10 is removed to expose a portion of absorbent pad 18. The user may grip the package 10 and apply the exposed portion of absorbent pad 18 to a patient, as illustrated in FIG. 4.

Lenarz '217 (column 1, lines 23-41) mentions U.S. Pat. Nos. 4,427,111 and 5,046,608, both to Laipply. The Laipply Patents show a device in which an absorbent pad is folded in the sealed package, which is opened flat for use. Laipply '111 illustrates a number of alcohol or other fluid applicators. At column 5, line 58 et seq., Laipply '111 describes FIGS. 2A-2D as disclosing a device 10 including a pad 11 which is attached (see column 8, lines 19-20) to the fluid-impermeable material 12 and is in a folded, closed position. As best seen in FIG. 2B, unsealed tabs or flanges 17 (column 6, lines 7-10) permit opening the device 10 to expose the pad for use. Laipply '608 notes at column 8, line 57 et seq., situations where it is undesirable to get fluid from the absorbent pad (11 in FIGS. 2A-2C) on the user's fingers.

As described at column 8, lines 19-41 of Laipply '111, the package 12 of FIG. 2D is preferably formed of a metal foil 20 and a thermoplastic liner 21. (See column 6, lines 52-59.) An interface material 23 may be disposed between the pad 11 and plastic liner 21 and heated to cause the interface material 23 to bond with the surface 24 of pad 11 and the plastic liner 21. At column 8, lines 42-48, other techniques for attaching the pad 11 to the package material 12 are briefly described.

The embodiment illustrated in FIGS. 8A through 8C, as described at column 12, lines 20-41 of Laipply ' 111, provides a “handle portion” 226 formed by putting a crimp in the package material 222. As described starting at column 14, line 57, an integral fluid-applying device 220 includes a rectangular pad 221 adhered to the packaging material 222 having a crimped handle portion 226.

SUMMARY OF THE INVENTION

Generally, the present invention provides a liquid-permeable, non-contaminating pad which is secured to a layer of impervious material to provide a “backed pad”, and which is contained within an impervious, manually openable package which is sealed against the environment and which provides within the sealed package an environment which is free of micro-contaminants. (The term “micro-contaminants” and “free of micro-contaminants” are defined below.) One aspect of the present invention provides that the impervious layer to which the backed pad is secured comprises a base layer of the sealed package, the base layer having a cover layer which is peripherally sealed to the base layer to provide a sealed package completely enclosing the pad within the sealed area.

Specifically, in accordance with the present invention there is provided a sealed package comprising an impervious base layer having a pad-receiving surface on which is disposed a liquid-permeable pad, and an impervious cover layer having a pad-facing surface, the cover layer being secured to the base layer by a rupturable seal, with the pad-facing surface fully overlying the pad. The pad-facing surface, the pad-receiving surface and the pad are free of micro-contaminants, whereby the pad is hermetically sealed within the package in an environment which is free of micro-contaminants, and may be exposed for use by at least partly separating the cover layer from the base layer.

Other aspects of the present invention provide the following features, alone or in combination of two or more. The liquid-permeable pad may be affixed directly to the pad-receiving surface of the base layer; the pad may be a dry pad and the sealed package may be free of liquid agents; alternatively, one or more liquid agents may be impregnated in the pad within the sealed package; and, in certain aspects, the pad has a periphery and the base layer and the pad are configured so that the base layer extends beyond the entire periphery of the pad to leave a continuous peripheral portion of the base layer uncovered by the pad.

Another aspect of the present invention provides for a sealed package comprising an impervious base layer having a pad-receiving surface on which a liquid-permeable pad having a periphery is affixed, the pad being selected from the group consisting of one or more of non-woven and/or washed woven materials, the base layer and the pad being configured so that the base layer extends beyond the entire periphery of the pad to leave a continuous peripheral portion of the base layer uncovered by the pad. An impervious cover layer has a pad-facing surface and is secured to the peripheral portion of the base layer by a rupturable, peripheral seal, with the pad-facing surface fully overlying the pad. The pad-facing surface, the pad-receiving surface and the pad being free of micro-contaminants, whereby the dry pad is hermetically sealed within the package in an environment which is free of micro-contaminants, and may be exposed for use by at least partly separating the cover layer from the base layer by pulling the respective layers apart to rupture at least a portion of the peripheral seal.

Other aspects of the present invention provide for the following features, alone or in combination of two or more. The rupturable seal may be a peripheral seal which encircles the pad and defines an extra-peripheral area of the package lying outside the seal, with at least a portion of the extra-peripheral area left unsealed so that the base and cover layers are readily separable from each other to expose at least part of the pad for use; the pad may comprise a single layer of material and lie flat and unfolded within the package; the pad may comprise a 100% polyester fabric which is free of chemical binders, salts, glue, bleach and cellulose; the pad may comprise a fabric having a basis weight of from about 2.7 to 4 ounces per square yard; the pad may be comprised of a non-woven fabric; both the base layer and the cover layer may comprise aluminum foil having adhered to the entirety of their respective pad-receiving and pad-facing surfaces a plastic film; and the rupturable seal may enclose and define a sealed area of the package, the package further comprising a retention opening outside the sealed area, the retention opening being configured to receive and retain therein a length of optic fiber having a connector affixed to at least one end thereof.

In accordance with a method aspect of the present invention, there is provided a method of making the sealed package described above, the method comprising the following steps. An impervious base layer having a pad-receiving surface which is free of micro-contaminants is prepared, and a pad which is free of micro-contaminants is affixed to the pad-receiving surface. An impervious cover layer having a pad-facing surface which is free of micro-contaminants is prepared and the cover layer is secured to the base layer by a rupturable seal, with the pad-facing surface fully overlying the pad. Consequently, the pad is hermetically sealed within the package in an environment which is free of micro-contaminants, and the pad may be exposed for use by at least partly separating the cover layer from the base layer.

Another method aspect of the invention provides that the steps of preparing the cover layer and the base layer each includes securing one or more plastic layers to an aluminum layer, and the pad comprises a non-woven polyester material.

Other aspects of the present invention will be discerned in the following description and the appended drawings.

As used herein and in the claims, the following terms, whether in singular or plural form, have the indicated meanings. A “plastic” means a synthetic organic polymeric material. An “impervious layer” is one or more layers of one or more materials which are impervious to passage therethrough of moisture, air and the treatment liquid, if any, with which the pad may optionally be impregnated while sealed in the package of the present invention. The term “micro-contaminants” means contaminants including, but not limited to, micron-sized particles of any material, such as dust motes, micron-sized droplets or other forms of skin oils or other oils, grease, plasticizers, plastisols or oily or other materials which are released from adhesives, from plastic sheets or from other plastic materials or the like, particles of starch, sizing or other materials, lint or threads from paper or other cellulosic materials, woven or non-woven materials, including particles, threads and droplets as small as one micron in diameter, or even smaller, or smears or films of liquids or other materials. A material or package environment which is stated to be “free of micro-contaminants” means a material or package environment in which the level of micro-contaminants, if any, is low enough that three or more passes of the end of an optic fiber over a cleaning pad just removed from the sealed package environment will leave at least the light-transmitting portion of the optic fiber end free of micro-contaminants. The term “free of micro-contaminants” also means and embraces freedom from contaminants larger than micro-contaminants. A “contaminant” is any material which would diminish light transfer through an optic fiber if disposed on the end face of the optic fiber itself (as distinguished from the surrounding epoxy and ceramic (or other material) header, or if otherwise disposed in the light-transmission path of the optic fiber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a sealed package in accordance with one embodiment of the claimed invention;

FIG. 2 is a side view in elevation of the sealed package of FIG. 1;

FIG. 3 is a plan view of the opened package of FIGS. 1 and 2, with the cover layer omitted;

FIG. 4 is a side elevation view of the opened package of FIG. 3 being used to clean the end of an optic fiber;

FIG. 5 is a view corresponding to that of FIG. 3, but schematically showing use of the opened package to clean the end of an optic fiber;

FIG. 6A is a schematic view showing the tip of an optic fiber with a dome-shaped end being cleaned on a pad in accordance with the practice of the present invention;

FIG. 6B is a schematic view showing the tip of an optic fiber with a beveled end being cleaned on a pad in accordance with the present invention; and

FIG. 7 is a plan view of a second embodiment of a sealed package in accordance with the present invention, showing an optic fiber cable with connector secured to the unopened package.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

As shown in FIGS. 1-3, a sealed foil package 10 is comprised of a cover layer 10a sealed to a base layer 10b along the entire periphery of the package at seal 12, as best shown in FIG. 3 (from which cover layer 10a is omitted). Cover layer 10a and base layer 10b are each impervious layers, i.e., they are impervious to passage therethrough of moisture and air and any treatment substance which may be contained within package 10. Layers 10a and 10b may be the same or different materials and may comprise any suitable impervious materials. For example, layers 10a and 10b may comprise conventional packaging material comprised of aluminum foil coated on both sides with a plastic layer such as low-density polyethylene. The materials of layers 10a and 10b are peripherally sealed together (seal 12) by any suitable means such as thermal bonding, ultrasonic welding, thermal or magnetic induction, adhesives, mechanical “zip-lock” type seals, etc., as is well-known in the art. An opening end 10c (FIG. 1) is formed by leaving unsealed an area which is large enough to facilitate manual opening of package 10 by separating and pulling apart cover layer 10a and base layer 10b. The area of package 10 outside peripheral seal 12 defines an extra-peripheral area 11 (FIGS. 1 and 2). A single-use seal or a reusable mechanical seal or a resealable adhesive seal may be utilized. Reusable seals permit resealing and subsequent reopening of package 10 for multiple use embodiments of the invention.

A pad 14 is made of any suitable absorbent material, such as polyester woven or non-woven fabric, and is securely bonded to base layer 10b by any suitable means such as those mentioned above to make seal 12, except that there is no need or reason for a reusable seal as pad 14 is preferably permanently secured to base layer 10b, for simplicity of construction. In the illustrated embodiment, thermal bonding is used in a pattern of spot-bondings 14a shown in FIG. 3 to non-removably affix pad 14 to base layer 10b. Obviously, other bonding patterns may be employed to secure pad 14 to an impervious backing layer such as base layer 10b. Pad 14 may be bonded to base layer 10b at all or part of the periphery of pad 14, or in a grid or other pattern or in a full coverage pattern. Top side 14b (FIG. 4) of pad 14 faces cover layer 10a and pad 14 is absorbent in order that it can absorb through top side 14b and retain a treatment substance in liquid, gel or pulverulent form. Thus, pad 14 is thick enough to retain a desired quantity of treatment substance. The bottom side (unnumbered) of pad 14, i.e., the side of pad 14 affixed to base layer 10b, may optionally be lined with any suitable material to facilitate bonding of pad 14 to base layer 10b. Pad 14 should be made of a fabric which does not generate particles large enough to interfere with light transmission through the end face of optic fibers. To that end, pad fabric ideally should not generate any particles. As a practical matter, the pad fabric should not generate particles larger than about 2 microns in diameter, preferably, it should not generate particles larger than about 1 micron in diameter. Ideally, any particles generated will be few in number and less than one micron in diameter, preferably less than one-half micron in diameter. Particles are often generated from fabrics which have been treated with or contain chemical binders, bleach (which weakens some fibers), salts, sizing, detergents, surfactants, glue or starch (some of which will separate from the fibers) or from fabrics which contain residues or threads which may separate from the fabric as lint or the like. Inasmuch as woven fabrics are usually treated at least with sizing and usually with both sizing and bleach, in order to avoid or minimize the generation of micron-size particles large enough to significantly attenuate the passage of light through the end face of an optical fiber, non-woven fabrics are preferred. Further, fabrics which are free of cellulose or other natural fibers are preferred because fabrics made of or including cellulose or other natural fibers tend to generate particles of problematic size and quantity. Accordingly, non-woven, unsized and unbleached fabrics are preferred. A highly preferred material for the fabric of the pad 14 is a 100% polyester material manufactured without chemical binders or thermal bonding and made by using hydroentanglement. That is, high-pressure water jets are used to knit the individual fibers together into a non-woven fabric. It is also desirable that the fabric be thick enough so that dome-shaped or beveled faces of the ends of optic fibers, when held perpendicularly to the surface of the fabric, are sufficiently enclosed by the nap of the fabric to assure thorough cleaning. In this regard, see the description below of FIGS. 6A and 6B. A suitable fabric is available from LymTech, a division of the John R. Lyman Company of Chicopee, Mass. That Company offers under the designation C3H a hydroentangled, non-woven 100% polyester fabric having a basis weight in ounces per square yard (“oz/yd²”) of 3.2 (108.5 grams per square meter, “g/m²”) and an average thickness of 17.5 mils. Generally, a basis weight of from about 2.5 to 4.0 oz/yd² (84.8 to 135.6 g/m²), e.g., from about 2.7 to 3.8 oz/yd² (91.6 to 128.8 g/m²) is preferred. It has been found that fabrics with a basis weight less than about 2.5 oz/yd² (84.8 g/m²) are likely to be torn by the pressure of an optic fiber drawn across it, as illustrated in FIG. 4, thereby generating lint and thread particles. Fabrics with a basis weight above 4 add cost and bulk to the package without any noticeable advantage over fabrics whose basis weight falls within 2.5 to 4.0 oz/yd² (84.8 to 135.6 g/m²) range. (Any discrepancy between the same values given in English and metric units should be resolved in favor of the value in English units.) The materials used for the package and its seal should be such that opening of the sealed package does not tear or otherwise shred any material, as tearing or shredding may create problematic fiber particles or the like.

The exterior side of layers 10a and 10b may be made of any suitable material, including paper, provided that their interior surfaces, i.e., the pad-receiving surface of base layer 10b and the pad-facing surface of cover layer 10a, are made of a suitable material such as a plastic material, e.g., polyester or Surlyn, or other non-fiber material. However, it is preferable to avoid the use of fiber materials such as paper in order to reduce the presence of potential contaminants. Aluminum foil lined with a suitable plastic is a preferred material of construction for base layer 10b and cover layer 10a. Among other virtues, including imperviousness and freedom from fibers or particles, aluminum helps to dissipate static charges which may be generated upon opening the package or by dragging an optic fiber face across the fabric. Static charges are problematic because they may attract lint, dust motes or other particles.

Pad 14 may optionally be impregnated with any suitable treatment substance, for example, with a liquid treatment substance, such as a cleaning solvent, after which the package 10 is sealed by applying cover layer 10a and carrying out thermal bonding or the like to form seal 12, thereby enclosing pad 14 within the seal 12, which seals cover layer 10a to base layer 10b. The result is a sealed package 10 within which pad 14 is enclosed and sealed from the environment. Any suitable solvent or cleaning agent, such as a high purity mixture of alcohol and water, may be used to soak the pad 14. Alternatively, a suitable cleaning agent or solvent may be applied to the pad or a portion thereof only after opening the sealed package. By sealing a dry pad within the package without any liquid agents of any kind present, possible adverse effects of a liquid agent such as a solvent or cleaning agent on the package materials or the pad is avoided.

An alcohol/water mixture is well suited for cleaning the end faces of optic fiber lines or cables. For example, a mixture of 90 percent by volume of either high purity anhydrous grade isopropyl alcohol or high purity anhydrous grade ethyl alcohol plus 10 percent by volume deionized water makes a suitable cleaning agent for cleaning the end faces of optic fiber lines or cables. Such solvent facilitates cleaning the end face and also serves to dissipate or preclude the formation of static electricity generated upon the opening of package 10 and/or by the dragging of the optic fiber end face across the fabric during cleaning. As noted above, the pad 14 may be left dry in the sealed package and used dry, or the treatment substance, e.g., one of the above alcohol-water mixtures, may be applied to pad 14 or a portion thereof only after opening package 10, e.g., at the point of use.

In use, package 10 is opened by separating cover layer 10a from base layer 10b at opening end 10c. The chevron-like pattern of thermal seal 12 leaves a substantial portion of layers 10a and 10b unsealed at end 10c of package 10, thereby facilitating manually separating layers 10a and 10b from each other and pulling back cover layer 10a to expose pad 14 as shown in FIG. 4. The pad 14 may be used for any cleaning purpose such as, as illustrated in FIG. 4, cleaning the end face 16a of an optic fiber line 16. End face 16a protrudes from connector 18 and is cleaned by rubbing end face 16a in a linear direction as indicated by the arrows in FIG. 4, or, preferably, in only one direction as indicated in FIG. 5 and described below. Alternatively, layer 10b may be folded over a length of optic fiber line, cable or the like to permit drawing the pad 14 over a length of the optic fiber or the like, to clean it prior to making a splice-type connection.

In cases where the pad 14 within the sealed package is dry, a preferred technique for cleaning the optic fibers is to wet only about one-half the pad with the cleaning agent or solvent and to drag the end of the optic fiber through the wet portion of the pad and into the dry portion to dry the end of the optic fiber. Moistening a portion of pad 14 with a cleaning agent or solvent such as a water-alcohol mixture, prepares the pad 14 for use and helps to dissipate any static electric charges generated by opening sealed package 10 and/or by the dragging of the optic fiber end face across the fabric during cleaning. For example, FIG. 5 shows base layer 10b from which cover layer 10a (not shown in FIG. 5) has been removed, leaving the residue of seal 12 and pad 14 exposed. If pad 14 is a dry pad, the user will preferably moisten a portion only of it with a suitable liquid cleaning agent such as a mixture of isopropyl or ethyl alcohol and deionized water. In FIG. 5, area 14a represents the moistened area of pad 14 and area 14b, demarcated from area 14a by the vertical (as viewed in FIG. 5) unnumbered dash line, is left dry. Area 14a should be moistened sufficiently to adequately clean the optic fiber end but not excessively, as too much cleaning agent will not be adequately dried by dry end 14b and may remain on the fiber end. The arrows A, B and C show the several passes of the tip 16a (FIG. 4) of the optic fiber 16 from the wetted area 14a into the dry area 14b. After being rubbed along the path of arrow A, the tip 16a is lifted clear of pad 14 and returned to area 14b at the origin of arrow B. As many passes as required are made, with care being taken to avoid twice traversing the same part of pad 14. That is, travel paths represented by arrows A, B and C should be slightly spaced-apart and not cross each other to avoid picking up previously deposited (onto pad 14 from tip 16a) contaminants.

FIG. 6A shows a dome-shaped tip 16a′ of optic fiber 16′, which has a ceramic jacket 17′ and an optic fiber strand 19′ extending therethrough. The pad 14 has a thickness t which is thick enough to encase tip 16a′. Similarly, FIG. 6B shows a beveled tip 16a″ of optic fiber 16″, comprised of ceramic jacket 17″ with optic fiber strand 19″.

Manufacture of the pad 14 and the sealed package 10 including pad 14, is preferably carried out under clean-room conditions free of dust, lint, etc. The degree of cleanliness required in the practices of the present invention is generally greater than that required for medical products. While medical products, such as alcohol-soaked pads contained with sealed aluminum foil/plastic packages must be sterile, they need not be “clean” in the sense that medical products can readily endure the presence of trace amounts of oils or of numerous particles greater or smaller than one micron, provided that the trace amounts of oils and/or the particles are sterile. Because the diameter of an optic fiber may be as small as 8 microns, the optic fibers should be free of micron-size particles greater than about one micron in diameter. Preferably, the sealed package of the present invention is free of trace oils and contaminant particles greater than one-half micron in diameter. For example, a dust mote or other particle three microns in diameter which lands on the end face of an optic fiber 8 millimeters in diameter will obscure a significant percentage of the light-transmitting surface area of the end face. The same is true with trace oils which can leave a smear, film or haze-like residue that can reduce or block the light-transmitting surface area of the end face. While such contamination is not visible or apparent to the naked eye, this contamination is readily seen when viewed at high magnification of 200× or more as when using a special fiber inspection scope such as the Noyes “OFS 300-200C; optical fiber scope”, made by Noyes/AFL Telecommunications, Belmont, N.H., or the equivalent. Typical magnifications at which the optic fiber ends are examined with such optical fiber scopes are 70×, 200× and 700×.

The clean-room conditions under which the sealed package is manufactured includes avoiding touching the pad 14 or the inner, pad-facing and pad-receiving surfaces of the package with fingers or hands because the oils and perspiration inherent on human skin severely contaminate the materials. Tests have shown that even fleeting contact of the pad with uncovered finger tips results in a disastrous rise in the rate of failure to adequately clean optic fiber end faces. In one test, normal handling of the pads as required during manufacture by workers with clean but ungloved hands, resulted in a 70% rate of failure to provide acceptable cleaning of optic fiber ends by the method illustrated in FIG. 5 and described herein, using a mixture of high purity anhydrous grade 98% isopropyl alcohol in deionized water. The cleaning was deemed to be a failure if the optic fiber end “cleaned” with the pad sustained any measurable loss of light transmission through the cleaned end face of the optic fiber, or any form of visible streaking, smearing caused by residues of oils, liquid contaminants, or the presence of one or more particles of solid particulate of size sufficient to cause at least some measurable blockage of light transmission, as determined by visual inspection using a fiber inspection scope of the type described above.

Operators working on manufacturing the sealed packages of the invention must utilize gloves which are free from lubricating powders such as talc, and which are also free of oily residues of plasticizer or plastisols from their manufacture. Use of plastics which include or exude even a minute amount of such oily substances has been found to seriously and adversely affect the ability of the cleaning pad to provide satisfactorily clean end faces for optic fibers. In another manufacturing test, workers using gloves made of either vinyl or latex which had dipped their gloved fingers into alcohol to provide cleaner glove surfaces as well as a better grip on the pads, also resulted in a high rate of failure. Investigation showed that the alcohol apparently leached a plasticizer from the gloves which plasticizer was transferred to the pads and some of it was deposited on the “cleaned” ends of the optic fibers. It has been found that for purposes of the present invention nitrile gloves free of talc or other lubricants are satisfactory for handling the pad 14, and for contact with the interior portions generally of package 10.

The present invention is not limited to cleaning optic fiber lines or cables, but provides an inexpensive, portable, cleaning (or other treatment) pad which is sealed in an environment which is “clean-room” free of micro-contaminants. The pad 14 may be packaged dry, and solvent or other liquid or other treatment substance added afterwards, or the treatment substance may be applied to pad 14 before sealing package 10. The treatment substance need not be a liquid, but could be a paste or a gel. Polishing, smoothing, cleaning and application of treatment, therapeutic or test substances in procedures which require or are enhanced by the sealed package being free of micro-contaminants are among the uses to which the present invention may be put. The impervious backing on pad 14 protects the user's fingers from the treatment substance and reduces the possibility of contamination of the test or treatment site by the user's fingers.

The present invention differs from known products such as packaged alcohol wipes because, in the case of the present invention, the pad 14 is made of relatively (as compared to starched, bleached, natural fiber, etc., fabrics) non-contaminating fabric such as 100% polyester non-woven fabric and the interior of the package is made from non-contaminating, static-dissipating materials. Further, manufacturing of the sealed packages of the present invention is carried out under clean-room conditions. Contact with the pad 14 or the interior sides of the base layer and cover layer is limited to contact with gloved bands wearing gloves which themselves are non-contaminating in that they do not have talc or residues of oily material such as plasticizers. The pad 14 is desirably made of at least a 2.5 oz/yd² (84.8 g/m²) basis weight material, to provide sufficient thickness (“t” in FIGS. 6A and 6B) to insure good cleaning of the tip (16a′, 16a″) of the optic fiber. It is preferred that the pad material not be folded, because folding forms a crease which may fatigue the fibers to the point where the crease causes fibers to break or otherwise generates undesirable micron-size particulates.

It is within the purview of the invention to provide pad 14 with a backing layer other than the base layer 10b and to enclose pad 14 and its backing layer within sealed package 10. However, for simplicity and efficiency of construction, it is preferred that pad 14 be directly adhered to backing layer 10b. The backing layer desirably is made thick and resilient enough to provide a secure base for the pad, yet is resilient enough to give somewhat under pressure of the end of the optic fiber to insure that the optic fiber end makes good contact with the cleaning pad, as illustrated in FIGS. 6A and 6B.

Optic fiber connectors such as connector 18 may measure 1.25, 1.6, 2.0 or 2.5 millimeters wide and the glass optic fiber strand 19 of optic fiber 16 contained within such connectors are typically 8 microns in diameter for telecommunications or other electronic equipment or 25 microns in diameter for medical instrument applications. For comparison, the average human hair has a diameter of about 40 microns. When it is considered that the optic fiber end may have an effective diameter of only 8 or 25 microns, it will be appreciated that trace amounts of oil or the like or extremely small particles or threads, as small as two, three or four microns in diameter, or even less, could have disastrous effects on the ability of the optic fiber to transmit light if the thread or particle lies across the face of the optic fiber.

The construction and clean-room manufacturing conditions provide an impervious backing layer to pad 14 and keeps pad 14 and its solvent or other treatment substance clean and untouched during use. In this way, the most stringent cleaning requirements, such as those which obtain in connection with on-site cleaning of the end faces of optic fiber lines or cables, may be successfully carried out. The package 10 is sealed and the pad 14 is protected until it is ready for use. If, in use, the user has to pick up pad 14, for example, to fold it around a length of optic fiber line or the like, the user does not contaminate with perspiration or oil from the user's fingers the surface of the pad 14 or the treatment substance, e.g., a solvent, or get the treatment substance on his or her fingers. This is because the user is able to pick up and hold the backed pad 14 by taking between the fingers the impervious backing layer, base layer 10b in the illustrated embodiment, and need not touch pad 14 itself.

The present invention is especially well suited for cleaning optic fiber lines and cables although, as stated above, it is not limited to that field. Some studies have shown that a failure rate of about 30 percent attends the making of optic fiber connections in the field, using connectors such as connector 18 illustrated in FIG. 4. Approximately 90 percent of such failures occur because of end face (16a in FIG. 4) contamination of the optic fiber line. As noted above, impregnation of the cleaning pad 14 with cleaning solvent or other liquid or paste treatment substance prior to sealing package 10 helps to eliminate static charge which may be generated when separating cover layer 10a from base layer 10b and/or the dragging of the optic fiber end face across the fabric during cleaning. This is highly advantageous in cleaning optic fibers because generating an electrostatic charge tends to attract airborne dust particles and motes. The above-described advantages of the present invention over known materials for cleaning or other uses are especially important for cleaning optic fibers. By protecting the user's fingers from contact with solvent or other materials on the pad 14, the user's fingers are not contaminated with the solvent, or chilled by evaporation of alcohol-containing or other such solvents. This can be a not insignificant factor when working in cold weather as it may obviate the need for gloves. Further, by folding the impervious layer-backed cleaning pad 14 about the length of optic fiber or the like, materials such as the “gooey material” used to coat optic fibers or optic fiber cables (bundles of optic fibers) can readily be cleaned away to facilitate splicing without the user's fingers being contaminated by the “gooey stuff”.

FIG. 7 shows a package 110 which is identical to package 10 of FIG. 1 except that it has a retainer opening provided by a “buttonhole” 20 formed in opening end 10c outside the sealed periphery formed by seal 12, that is, in the extra-peripheral area 11 thereof. A length of optic fiber 16 having a connector 18 affixed to one end thereof is threaded through slit 20. This provides a combination which may be sold as a unit, so as to provide a cleaning pad with the optic fiber connector, for use in cleaning the end faces of the optic fiber lines prior to installation.

While the invention has been described in detail with respect to a particular embodiment thereof, it will be appreciated that numerous variations may be made to the described and illustrated embodiment which nonetheless lie within the scope of the present invention.

Claims

1. A sealed package comprising: an impervious base layer having a pad-receiving surface on which is disposed a liquid-permeable pad;an impervious cover layer having a pad-facing surface, the cover layer being secured to the base layer by a rupturable seal, with the pad-facing surface fully overlying the pad, the pad-facing surface, the pad-receiving surface and the pad being free of micro-contaminants, whereby the pad is hermetically sealed within the package in an environment which is free of micro-contaminants, and may be exposed for use by at least partly separating the cover layer from the base layer.

2. The sealed package of claim 1 wherein the liquid-permeable pad is affixed directly to the pad-receiving surface of the base layer.

3. The sealed package of claim 1 wherein the pad is a dry pad and the sealed package is free of liquid agents.

4. The sealed package of claim 1 wherein one or more suitable liquid agents are impregnated in the pad within the sealed package.

5. The sealed package of any one of claims 1, 2, 3 or 4 wherein the pad has a periphery and the base layer and the pad are configured so that the base layer extends beyond the entire periphery of the pad to leave a continuous peripheral portion of the base layer uncovered by the pad.

6. A sealed package comprising: an impervious base layer having a pad-receiving surface on which a liquid-permeable pad having a periphery is affixed, the pad being selected from the group consisting of one or more of non-woven and washed woven materials, the base layer and the pad being configured so that the base layer extends beyond the entire periphery of the pad to leave a continuous peripheral portion of the base layer uncovered by the pad;an impervious cover layer having a pad-facing surface and secured to the peripheral portion of the base layer by a rupturable, peripheral seal, with the pad-facing surface fully overlying the pad, the pad-facing surface, the pad-receiving surface and the pad being free of micro-contaminants, whereby the dry pad is hermetically sealed within the package in an environment which is free of micro-contaminants, and may be exposed for use by at least partly separating the cover layer from the base layer by pulling the respective layers apart to rupture at least a portion of the peripheral seal.

7. The sealed package of claim 6 wherein the pad is a dry pad and the sealed package is free of liquid agents.

8. The sealed package of claim 1 or claim 6 wherein the rupturable seal is a peripheral seal which encircles the pad and defines an extra-peripheral area of the package lying outside the seal, with at least a portion of the extra-peripheral area left unsealed so that the base and cover layers are readily separable from each other to expose at least part of the pad for use.

9. The sealed package of any one of claims 1, 2, 3, 4 or 6 wherein the pad comprises a single layer of material and lies flat and unfolded within the package.

10. The sealed package of claim 1 or claim 6 wherein the pad comprises a 100% polyester fabric which is free of chemical binders, salts, detergents, surfactants, glue, bleach, starch and cellulose.

11. The sealed package of claim 10 wherein the pad comprises a fabric having a basis weight of from about 2.7 to 4 ounces per square yard.

12. The sealed package of claim 10 wherein the pad is comprised of a non-woven fabric.

13. The sealed package of claim 1 or claim 6 wherein both the base layer and the cover layer comprise aluminum foil having adhered to the entirety of their respective pad-receiving and pad-facing surfaces a plastic film.

14. The sealed package of claim 1 or claim 6 wherein the rupturable seal encloses and defines a sealed area of the package, and further comprising a retention opening outside the sealed area, the retention opening being configured to receive and retain therein a length of optic fiber having a connector affixed to at least one end thereof.

15. A method of making the sealed package of any one of claim 1, claim 2, claim 3, claim 6 or claim 7 comprising: preparing an impervious base layer having a pad-receiving surface which is free of micro-contaminants;affixing to the pad-receiving surface a pad which is free of micro-contaminants;preparing an impervious cover layer having a pad-facing surface which is free of micro-contaminants and securing the cover layer to the base layer by a rupturable seal with the pad-facing surface fully overlying the pad;whereby the pad is hermetically sealed within the package in an environment which is free of micro-contaminants and may be exposed for use by at least partly separating the cover layer from the base layer.

16. The method of claim 15 wherein the steps of preparing the cover layer and the base layer each includes securing one or more plastic layers to an aluminum layer, one of the plastic layers comprising the pad-receiving surface and another of the plastic layers comprising the pad-facing surface, and the pad comprises a non-woven polyester material.