minitech 是正确的，animation-delay 指定了动画开始之前的延迟，而 NOT 指定了迭代之间的延迟。 The editors draft of the spec 很好地描述了它，并且有一个关于你描述的这个特性的讨论 here 这暗示了这个迭代延迟特性。
虽然在 JS 中可能有一种解决方法，但您可以仅使用 CSS 来伪造进度条耀斑的迭代延迟。
通过声明flare div position:absolute 和父div overflow: hidden，将100% 关键帧状态设置为大于进度条的宽度，以及playing around with the cubic-bezier timing function 和左偏移值，您可以模拟一个ease-in-out 或 linear 定时带有“延迟”。
编写一个less/scss mixin 来精确计算左偏移和计时函数来得到这个结果会很有趣，但我现在没有时间摆弄它。不过很想看到这样的东西！
这是我为展示这一点而拼凑的一个演示。 （我试图模拟 Windows 7 进度条，但有点短，但它说明了我在说什么）
演示：
http://codepen.io/timothyasp/full/HlzGu
<!-- HTML -->
<div class="bar">
<div class="progress">
<div class="flare"></div>
</div>
</div>
/* CSS */
@keyframes progress {
from {
width: 0px;
}
to {
width: 600px;
}
}
@keyframes barshine {
0% {
left: -100px;
}
100% {
left: 1000px;
}
}
.flare {
animation-name: barshine;
animation-duration: 3s;
animation-direction: normal;
animation-fill-mode: forwards;
animation-timing-function: cubic-bezier(.14, .75, .2, 1.01);
animation-iteration-count: infinite;
left: 0;
top: 0;
height: 40px;
width: 100px;
position: absolute;
background: -moz-radial-gradient(center, ellipse cover, rgba(255,255,255,0.69) 0%, rgba(255,255,255,0) 87%); /* FF3.6+ */
background: -webkit-gradient(radial, center center, 0px, center center, 100%, color-stop(0%,rgba(255,255,255,0.69)), color-stop(87%,rgba(255,255,255,0))); /* Chrome,Safari4+ */
background: -webkit-radial-gradient(center, ellipse cover, rgba(255,255,255,0.69) 0%,rgba(255,255,255,0) 87%); /* Chrome10+,Safari5.1+ */
background: -o-radial-gradient(center, ellipse cover, rgba(255,255,255,0.69) 0%,rgba(255,255,255,0) 87%); /* Opera 12+ */
background: -ms-radial-gradient(center, ellipse cover, rgba(255,255,255,0.69) 0%,rgba(255,255,255,0) 87%); /* IE10+ */
background: radial-gradient(ellipse at center, rgba(255,255,255,0.69) 0%,rgba(255,255,255,0) 87%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#b0ffffff', endColorstr='#00ffffff',GradientType=1 ); /* IE6-9 fallback on horizontal gradient */
z-index: 10;
}
.progress {
animation-name: progress;
animation-duration: 10s;
animation-delay: 1s;
animation-timing-function: linear;
animation-iteration-count: infinite;
overflow: hidden;
position:relative;
z-index: 1;
height: 100%;
width: 100%;
border-right: 1px solid #0f9116;
background: #caf7ce; /* Old browsers */
background: -moz-linear-gradient(top, #caf7ce 0%, #caf7ce 18%, #3fe81e 45%, #2ab22a 96%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#caf7ce), color-stop(18%,#caf7ce), color-stop(45%,#3fe81e), color-stop(96%,#2ab22a)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #caf7ce 0%,#caf7ce 18%,#3fe81e 45%,#2ab22a 96%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #caf7ce 0%,#caf7ce 18%,#3fe81e 45%,#2ab22a 96%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #caf7ce 0%,#caf7ce 18%,#3fe81e 45%,#2ab22a 96%); /* IE10+ */
background: linear-gradient(to bottom, #caf7ce 0%,#caf7ce 18%,#3fe81e 45%,#2ab22a 96%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#caf7ce', endColorstr='#2ab22a',GradientType=0 ); /* IE6-9 */
}
.progress:after {
content: "";
width: 100%;
height: 29px;
right: 0;
bottom: 0;
position: absolute;
z-index: 3;
background: -moz-linear-gradient(left, rgba(202,247,206,0) 0%, rgba(42,178,42,1) 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, right top, color-stop(0%,rgba(202,247,206,0)), color-stop(100%,rgba(42,178,42,1))); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(left, rgba(202,247,206,0) 0%,rgba(42,178,42,1) 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(left, rgba(202,247,206,0) 0%,rgba(42,178,42,1) 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(left, rgba(202,247,206,0) 0%,rgba(42,178,42,1) 100%); /* IE10+ */
background: linear-gradient(to right, rgba(202,247,206,0) 0%,rgba(42,178,42,1) 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#00caf7ce', endColorstr='#2ab22a',GradientType=1 ); /* IE6-9 */
}
.bar {
margin-top: 30px;
height: 40px;
width: 600px;
position: relative;
border: 1px solid #777;
border-radius: 3px;
}