Compound mold and structured surface articles containing geometric structures with compound faces and method of making same
a technology of geometric structure and compound face, applied in the field of structured surface articles, can solve the problems of inability to make small cube corner elements, inability to meet the needs of small cubes,
Inactive Publication Date: 2005-07-07
3M INNOVATIVE PROPERTIES CO
View PDF36 Cites 2 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
This approach enables the production of high-quality, small-scale cube corner elements with enhanced design flexibility, achieving higher optical efficiency and uniformity in retroreflective surfaces, including those with PG cube corner elements, by maintaining precise alignment and angular orientations across the substrate.
Problems solved by technology
Each of these techniques has its own benefits and limitations.
However, such techniques are impractical for making small cube corner elements (e.g. those having a cube height less than about 1 millimeter) because of the large number of pins and the diminishing size thereof required to be precisely machined and then arranged in a bundle to form the mold.
However, design flexibility suffers relative to that achievable by pin bundling.
However, a significant drawback to direct machining techniques has been reduced design flexibility in the types of cube corner geometry that can be produced.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0045]FIGS. 2 and 3 illustrate an assembly 20 useful for making a structured surface (see FIGS. 9-10) in accordance with the present invention. The assembly 20 includes a blank 22 bonded to a first machining base 24 by a first bonding layer 26. In the illustrated embodiment, the blank 22 is a continuous structure that includes a deck 27 and a series of reference pads 30a, 30b, 30c, 30d, 30e, 30f (collectively referred to as 30) that extend above surface 32. In one embodiment, the deck 27 has a height 34 generally equal to a height 36 of the reference pads 30. The number of reference pads 30 can vary depending upon the application. In an alternate embodiment, the deck 27 and the reference pads 30 can be discrete elements bonded to the first machining base 24, rather than the continuous blank 22 shown in FIG. 2.
[0046] Blank 22 is composed of a material that can be scribed, cut, or otherwise machined without significant post-machining deformation and without substantial burring. This ...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| height | aaaaa | aaaaa |
| included angles | aaaaa | aaaaa |
| angle | aaaaa | aaaaa |
Login to View More
Abstract
A structured surface articles such as molds or sheeting are formed on a compound substrate including a machined substrate and a replicated substrate. In one embodiment, the structured surface is a cube corner element on a compound substrate. In another embodiment, the structured surface is a geometric structure that has a plurality of faces, where one face is located on the machined substrate and another face is located on the replicated substrate. In yet another embodiment, at least some of the faces include a compound face with a portion formed on the machined substrate and a portion formed on the replicated substrate. The method of making a structured surface article including a geometric structure having a plurality of faces includes forming an array of geometric structures in a first surface of a machined substrate; passivating selected locations of the first surface of the machined substrate; forming a replicated substrate of the machined substrate to form a compound substrate; forming an array of second geometric structures on a second surface opposite the first surface on the machined substrate; and removing selected portions from the second surface of the machined substrate.
Description
BACKGROUND [0001] The present invention relates generally to structured surfaces fabricated using microreplication techniques. The invention has particular application to structured surfaces that comprise retroreflective cube corner elements. [0002] The reader is directed to the glossary at the end of the specification for guidance on the meaning of certain terms used herein. [0003] It is known to use microreplicated structured surfaces in a variety of end use applications such as retroreflective sheeting, mechanical fasteners, and abrasive products. Although the description that follows focuses on the field of retroreflection, it will be apparent that the disclosed methods and articles can equally well be applied to other fields that make use of microreplicated structured surfaces. [0004] Cube corner retroreflective sheeting typically comprises a thin transparent layer having a substantially planar front surface and a rear structured surface comprising a plurality of geometric stru...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & AuthorityApplications(United States)
IPC IPC(8): B29C33/38B29C33/42B29C59/02B29D11/00C23C22/24G02B5/124H01Q15/18
CPCB29C33/3842Y10T428/2457B29C59/02B29C59/022B29C59/026B29D11/00605B29L2011/0091G02B5/124H01Q15/18B32B3/30B32B3/28Y10T428/24521Y10T428/24612Y10T428/24479B29C33/42B29C33/38
InventorBENSON, GERALD M.SMITH, KENNETH L.
Owner3M INNOVATIVE PROPERTIES CO